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[comp.publish.cdrom] CD-Recordable FAQ, Part 1/4
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Message-ID: <cdrom/cd-recordable/part1_1223615169@rtfm.mit.edu> X-Last-Updated: 2008/10/09 From: fadden@fadden.com (Andy McFadden) Newsgroups: comp.publish.cdrom.hardware, comp.publish.cdrom.software, comp.publish.cdrom.multimedia, alt.comp.periphs.cdr, comp.answers Subject: [comp.publish.cdrom] CD-Recordable FAQ, Part 1/4 Summary: Frequently Asked Questions about CD recorders, CD-R media, CD-RW, and CD premastering. Date: 10 Oct 2008 05:07:13 GMT Archive-name: cdrom/cd-recordable/part1 Posting-Frequency: monthly Last-modified: 2008/10/09 Version: 2.71 Send corrections and updates to Andy McFadden (fadden@fadden.com). If you have a question you'd like to see answered in here, either post it to one of the comp.publish.cdrom newsgroups (if you don't have the answer), or send it to fadden@fadden.com (if you do). If you're reading this on a web page and want to check out the newsgroups, check out the following with a news reader. If you don't have one, you can post news and search for past articles on http://groups.google.com/: news:comp.publish.cdrom.hardware news:comp.publish.cdrom.software news:comp.publish.cdrom.multimedia news:alt.comp.periphs.cdr The HTML version of this FAQ is available from: http://www.cdrfaq.org/ Some translations are available (may be somewhat out of date): German: http://www.dvddemystifiziert.de/cdr/faq.html Turkish: http://www.tarman.ws/ Hungarian: http://delfin.klte.hu/~nagysz/cdrgyik/ French: http://www.lagravuredecd.com/ Italian: http://web.tiscali.it/marzonaontheweb/faq/faq.html Russian: http://members.tripod.com/greatkorzhik/cdrfaq.htm If a Usenet news posting appears to be cut off at the bottom, and you read news with a browser like Netscape Navigator, you may need to increase a buffer size. Please DO NOT post copies of the HTML version on your web site. I occasionally get e-mail from people reading versions that are several months old. Please use a link to the www.cdrfaq.org site instead. Contents ======== [0] Introduction [0-1] Legal noise (disclaimers and copyrights) [0-2] What does this FAQ cover (and not cover)? [0-3] What's new since last time? [0-4] Is the FAQ only available in English? [0-5] Appropriate use of the newsgroups [0-6] I'm having trouble, how do I ask for help? [0-7] Spelling and name conventions [0-8] Can I advertise on the FAQ pages? [0-9] Can you mail the FAQ to me? [1] Simple answers to simple questions [1-1] What's CD-R? CD-RW? [1-2] Are they identical to normal CDs? [1-3] Can I create new audio and data CDs? [1-4] Can I use it to copy my CDs? [1-5] How much can they hold? [1-6] Can I just copy files onto a CD-R like I would to a floppy? [1-7] What can you tell me about DVD, DVD-R, DVD-RAM, DVD-RW, etc? [1-8] Can I copy DVDs with a CD recorder? [1-9] What's the cheapest recorder and best place to buy media? [1-10] Can I get step-by-step installation and use instructions? [1-11] Can I download MP3s from the Internet and make an audio CD? [1-12] What does this term mean? Is there a glossary? [1-13] Do I need "music" blanks to record music? [1-14] How do I learn more? Is there a good book for beginners? [1-15] Why is this FAQ so far out of date? [2] CD Encoding [2-1] How is the information physically stored? [2-2] What is XA? CDPLUS? CD-i? MODE1 vs MODE2? Red/yellow/blue book? [2-3] How do I know what format a disc is in? [2-4] How does copy protection work? [2-4-1] ...on a data CD-ROM? [2-4-2] ...on an audio CD? [2-4-3] ...on an audio CD (Macrovision - SafeAudio) [2-4-4] ...on an audio CD (SunnComm - MediaCloQ and MediaMax CD3) [2-4-5] ...on an audio CD (Midbar Tech - Cactus Data Shield) [2-4-6] ...on an audio CD (Key2Audio / Sony DADC) [2-4-7] ...on an audio CD (BayView Systems - Duolizer) [2-4-8] ...on an audio CD (Sanyo) [2-4-9] How does the Doc-Witness OpSecure CD-ROM work? [2-4-10] What's the Sony BMG rootkit (First 4 Internet XCP)? [2-5] What's a multisession disc? [2-6] What are subcode channels? [2-7] Are the CD Identifier fields widely used? [2-8] How long does it take to burn a CD-R? [2-9] What's the difference between disc-at-once and track-at-once? [2-10] Differences between recording from an image and on-the-fly? [2-11] How does an audio CD player know to skip data tracks? [2-12] How does CD-RW compare to CD-R? [2-13] Can DVD players read CD-Rs? [2-14] Should I buy a DVD recorder instead? [2-15] What are "jitter" and "jitter correction"? [2-16] Where can I learn more about the history of CD and CD-R? [2-17] Why don't audio CDs use error correction? [2-18] How does CD-R compare to MiniDisc? [2-19] What does finalizing (and closing and fixating) do? [2-20] How are WAV/AIFF files converted into Red Book CD audio? [2-21] What does MultiRead mean? MultiPlay? [2-22] If recording fails, is the disc usable? [2-23] Why do recorders insert "00" bytes at the start of audio tracks? [2-24] How many tracks can I have? How many files? [2-25] Will SCMS prevent me from making copies? [2-26] Is a serial number placed on the disc by the recorder? [2-27] What's a TOC? How does it differ from a directory? [2-28] What's an ISO? A CIF? BIN and CUE? .DAT? [2-29] Why was 74 minutes chosen as the standard length? [2-30] Why is there a visibly unwritten strip near the CD-R hub? [2-31] What is "BURN-Proof"? "JustLink"? "Waste-Proof"? [2-32] Can playing CD-Rs in a DVD player hurt the discs? [2-33] Who *really* made this CD-R blank? [2-34] Can I make copies of DTS-encoded CDs? [2-35] Why 44.1KHz? Why not 48KHz? [2-36] What format are .CDA files in? [2-37] What are DD-R and DD-RW? [2-38] What's an ATIP? [2-39] What are "ML" discs and devices? [2-40] What's CD-MRW? Mount Rainier? EasyWrite? [2-41] What's Audio Master Quality (AMQ) recording? [2-42] Can I draw pictures on a disc with the recording laser? [2-43] What are the gory details about how are 1s and 0s encoded? [2-43-1] How does the laser read or write a disc? [2-43-2] How do pits and lands turn into 1s and 0s? What's EFM? [2-43-3] What's a frame? CIRC encoding? How does ECC work? [2-43-4] What's in a sector? [2-43-5] What's in a subcode channel? [2-43-6] I want even more details [2-44] Digital is better than analog, right? [2-44-1] What is "digital" and "digitization", anyway? [2-44-2] How does this relate to CD-DA? [2-45] What's a CDR-ROM? CD-PROM? [2-46] What's HD-BURN? GigaRec? [2-47] What are C2 errors? What do they say about disc quality? [2-48] What are CD+R and CD+RW? [2-49] What's HighMAT? [2-50] What's VariRec? [2-51] Will my CDs work on players in other countries? [2-52] Do CD-Rs have deeper pits? Are "shallow burns" bad? [2-53] What's a stacking ring? [3] How Do I... [3-1] How do I copy a CD-ROM? [3-1-1] Why can't I just do a block copy like a floppy? [3-2] How do I extract tracks from ("rip") or copy an audio CD? [3-2-1] How do I remove the voice from a CD track, leaving just music? [3-2-2] How do I encode a CD track to MP3? [3-3] How do I get rid of hisses and clicks on audio CDs? [3-4] How do I copy game console discs (e.g. Playstation, Dreamcast) [3-5] How do I get long filenames onto a disc? [3-5-1] ISO-9660 [3-5-2] Rock Ridge [3-5-3] HFS/HFS+ and Macintosh extensions to ISO-9660 [3-5-4] Joliet [3-5-5] Romeo [3-5-6] ISO/IEC 13346 and ISO/IEC 13490 [3-5-7] ISO-9660:1999 [3-6] How do I use a CD-i disc on a PC? [3-7] How can I extract disc and track titles from an audio CD? [3-8] How do I write more than 80 minutes of audio or 700MB of data? [3-8-1] How well do 80-minute CD-R blanks work? [3-8-2] How well do 90-minute and 99-minute CD-R blanks work? [3-8-3] How can I exceed the stated disc capacity ("overburning")? [3-9] How do I put photographs onto CD-ROM? [3-9-1] How do I create a PhotoCD? [3-9-2] How can I set up a photo album on CD-ROM? [3-9-3] How can I show digital photos on my DVD player? [3-10] How do I make a CD that will work on a PC or a Mac? [3-11] How do I access different sessions on a multi-session CD? [3-12] How do I transfer my records or cassettes to a CD? [3-12-1] ...with a stand-alone audio CD recorder? [3-12-2] ...with a CD recorder attached to my computer? [3-12-3] How can I clean up the audio before recording? [3-13] How do I transfer an audio DAT tape to CD? [3-14] How do I put audio and data on the same CD? [3-15] How do I make a bootable CD-ROM? [3-16] How do I convert home movies into video on CD? [3-16-1] How do I create a VideoCD from AVI or MPEG files? [3-16-2] How do I create an SVCD? [3-16-3] How do I create an AVCD? [3-17] How can I burn several copies of the same disc simultaneously? [3-18] Can I make copies of copies? [3-19] How can I compress or encrypt data on a CD-ROM? [3-20] Can I do backups onto CD-R? [3-21] How do I automatically launch something? Change the CD icon? [3-21-1] How does Windows "autorun" work? [3-21-2] How do I launch a document (like a web page)? [3-21-3] What autorun software is available? [3-22] How can I be sure the data was written correctly? [3-23] How do I create, copy, or play Audio Karaoke/CD+G discs? [3-24] How do I copy a CD-ROM with 3GB of data on it? A huge VideoCD? [3-25] How do I get my CD-R pressed into a real CD? [3-26] How do I make a CD without that two-second gap between tracks? [3-27] How can I record RealAudio (.ra), MIDI, WMA, and MP3 on a CD? [3-28] How do I add CD-Text information? [3-29] Can I distribute a web site on a CD-ROM? [3-30] How do I clean my CD recorder? [3-31] Is it better to record at slower speeds? [3-32] Where do I get drivers for my CD recorder? [3-33] Can I copy discs without breaking the law? [3-33-1] ...in the United States of America? [3-33-2] ...in Canada? [3-34] Can CD-Rs recorded at one speed be read at a different speed? [3-35] How do I make my CD-ROM work on the Mac, WinNT, and UNIX? [3-36] How do I put "hidden tracks" and negative indices on audio CDs? [3-37] Do I need to worry about viruses? [3-38] How do I cover up a bad audio track on a CD-R? [3-39] How do I duplicate this hard-to-copy game? [3-40] Should I erase or format a disc? How? [3-41] How do I equalize the volume for tracks from different sources? [3-42] How do I make a bit-for-bit copy of a disc? [3-43] How do I put punctuation or lower case in CD-ROM volume labels? [3-44] How do I extract audio tracks from an "enhanced" CD on the Mac? [3-45] How do I disable DirectCD for Windows? [3-46] How do I specify the order of files (e.g. sorting) on ISO-9660? [3-47] How do I put a password on a CD-ROM? [3-48] Can I record an audio CD a few tracks at a time? [3-49] How do I copy DVDs onto CD-R? [3-49-1] I heard about software that copies DVDs with a CD recorder! [3-50] How do I copy Mac, UNIX, or "hybrid" CD-ROMs from Windows? [3-51] How do I copy something in "RAW" mode? What's DAO-96? [3-52] How do I do cross-fades between audio tracks? [3-53] How do I create a CD with my favorite songs on it? [3-54] How do I record directly onto CD from a microphone? [3-55] Is it okay to record a CD from MP3? [3-56] How can I test a disc image before recording? [3-57] How do I clear the "read-only" flag under Windows? [3-58] How do I share a CD recorder across a network? [3-59] How do I write a large file across multiple discs? [3-60] What's the safest, most reliable way to write data to CD-R? [4] Problems [4-1] What does "buffer underrun" mean? [4-1-1] What's the deal with Windows Auto-Insert Notification (AIN)? [4-1-2] What's all this about Win9x VCACHE settings? [4-2] I can't get long Win95 filenames to work right [4-3] I can't read the multisession CD I just made [4-4] Write process keeps failing N minutes in [4-5] Why did my CD-R eject and re-load the disc between operations? [4-6] My CD-ROM drive doesn't like *any* CD-R discs [4-7] How do I avoid having a ";1" on my ISO-9660 discs? [4-8] I keep getting SCSI timeout errors [4-9] I'm having trouble writing a complete disc [4-10] What's the CDD2000 Write Append Error / spring problem? [4-11] Getting errors reading the first (data) track on mixed-mode CD [4-12] My recorder ejects blank discs immediately [4-13] I'm getting complaints about power calibration [4-14] My Adaptec 2940 pauses after finding my recorder [4-15] I can't see all the files on the CD-R [4-16] My multi-session disc only has data from the last session [4-17] I'm getting SCSI errors [4-18] Why doesn't the copy of an audio CD sound the same? [4-18-1] Why doesn't the audio data on the copy match the original? [4-18-2] The audio data matches exactly, why do they sound different? [4-19] Digital audio extraction of a track is shifted slightly [4-20] I can't play extracted audio files by double-clicking in Win95 [4-21] I can't read an ISO-finalized packet-written disc [4-22] I'm finding corrupted files on the CD-ROMs I write [4-23] Having trouble playing an audio CD in a home or car player [4-24] Having trouble using a CD-ROM on a different machine [4-25] I can't copy a VideoCD [4-26] The test write succeeds, but the actual write fails [4-27] I can no longer erase a particular CD-RW disc [4-28] Having trouble formatting discs with DirectCD [4-29] I can't write CD-Rs after installing Windows 98 [4-30] I can't use the copy of a CD-ROM after installing Windows 98 [4-31] The disc I was writing with DirectCD is now unreadable [4-32] I'm getting a message about 100 form transitions [4-33] My system hangs when I insert a blank disc [4-34] My CD-R discs don't work in my DVD player [4-35] I need help recovering data from a CD-ROM [4-36] What does "not convertible to CD quality" mean? [4-37] I inserted a CD-ROM but Windows thinks it's an audio CD [4-38] I get read errors when trying to copy a game [4-39] Restarting or shutting Windows down after recording causes hang [4-40] Why do CD-Rs play poorly when anti-skip protection is enabled? [4-41] I'm having trouble recording under Windows 2000 or WinXP [4-42] I formatted a CD-RW and only have about 530MB free [4-43] My CD recording software keeps crashing [4-44] Do I need to update my ASPI layer? [4-45] The write process completes, but the disc is still blank [4-46] My CD-RW drive doesn't work with my CD-RW blanks [4-47] Audio discs have crackling sounds on the last few tracks [4-48] Files in deep directories can be seen but not opened [4-49] My CD-ROM drive stopped working after uninstalling software [4-50] Audio CDs recorded from MP3s play back fast and high-pitched [4-51] Windows says access denied, can't create or replace file [4-52] I can't see any files on a CD-R or CD-RW from MS-DOS [4-53] My OS doesn't support ISO-13346 "UDF" [4-54] Why don't I get disc and track titles on my CD-Rs? [5] Hardware [5-1] Which CD recorder should I buy? [5-1-1] Yamaha [5-1-2] Sony [5-1-3] Smart & Friendly [5-1-4] Philips [5-1-5] Hewlett-Packard (HP) [5-1-6] Plasmon [5-1-7] Kodak [5-1-8] JVC [5-1-9] Pinnacle [5-1-10] Ricoh [5-1-11] Pioneer [5-1-12] Olympus [5-1-13] Optima [5-1-14] Mitsumi [5-1-15] DynaTek Automation Systems [5-1-16] Microboards of America [5-1-17] Micro Design International [5-1-18] MicroNet Technology [5-1-19] Procom Technology [5-1-20] Grundig [5-1-21] Plextor [5-1-22] Panasonic (Matsushita) [5-1-23] Teac [5-1-24] Wearnes [5-1-25] Turtle Beach [5-1-26] Creative Labs [5-1-27] Taiyo Yuden [5-1-28] Memorex [5-1-29] Hi-Val [5-1-30] Dysan [5-1-31] Traxdata [5-1-32] BenQ (nee Acer) [5-1-33] Waitec [5-1-34] BTC [5-1-35] Caravelle (Sanyo) [5-1-36] Micro Solutions [5-1-37] Pacific Digital [5-1-38] Iomega [5-1-39] Goldstar (LG Electronics) [5-1-40] AOpen [5-1-41] Toshiba [5-1-42] TDK [5-1-43] Lite-On [5-1-44] CenDyne [5-1-45] VST (SmartDisk) [5-1-46] ASUS [5-1-47] Samsung [5-1-48] APS / LaCie [5-2] How long do CD recorders last? [5-3] What kind of PC is recommended? [5-4] What kind of Mac is recommended? [5-5] Which standard CD-ROM drives work well with CD-R? [5-6] What kind of HD should I use with CD-R? Must it be AV-rated? [5-7] What SCSI adapter should I use with a CD recorder? [5-7-1] Adaptec - 1510/1522A/1540/1542CF [5-7-2] Adaptec - 2840/2910/2920/2930/2940 [5-7-3] ASUS - SC-200/SC-875 [5-7-4] Tekram - DC-390U/DC-390F [5-7-5] Adaptec - 1350/1460/1480 [5-8] Can I use a CD recorder as a general-purpose reader? [5-9] To caddy or not to caddy? [5-10] Can I burn CDs from a Jaz drive? Tape drive? [5-11] What is "Running OPC"? [5-12] What's the story with stand-alone audio CD recorders? [5-13] What's firmware? How and why should I upgrade my recorder? [5-14] How well do parallel-port, USB, and 1394 recorders work? [5-15] How should I configure my system for an ATAPI CD recorder? [5-15-1] Should I have DMA enabled for an ATAPI recorder in Windows? [5-16] How important is CD-RW? [5-17] What is an "MMC Compliant" recorder? [5-18] What do I need to record on a UNIX (Linux, Solaris, etc) system? [5-19] What do I need for recording CDs from a laptop? [5-20] I need to make *lots* of copies [5-21] How do I connect two drives to one sound card in a PC? [5-22] How fast is 1x? What are CAV, CLV, PCAV, and ZCLV? [5-23] Will playing CD-Rs damage my CD player? [5-24] Can I "overclock" my CD recorder? [5-25] I need some help installing the drive [5-26] How much power does a CD recorder use? [5-27] Will the laser in my drive wear out? [6] Software [6-1] Which software should I use? [6-1-1] Adaptec - Easy-CD, Easy-CD Pro, and Easy-CD Pro MM ("ECD") [6-1-2] Adaptec - CD-Creator ("CDC") [6-1-3] Gear Software - GEAR Pro [6-1-4] Roxio - Toast [6-1-5] CeQuadrat - WinOnCD [6-1-6] Young Minds, Inc. - CD Studio+ [6-1-7] Golden Hawk Technology (Jeff Arnold) - CDRWIN [6-1-8] Optical Media International - QuickTOPiX CD [6-1-9] Creative Digital Research - CDR Publisher [6-1-10] mkisofs [6-1-11] Asimware Innovations - MasterISO [6-1-12] Newtech Infosystems, Inc. (NTI) - CD-Maker [6-1-13] Cirrus Technology/Unite - CDMaker [6-1-14] Hohner Midia - Red Roaster [6-1-15] Dataware Technologies - CD Author [6-1-16] CreamWare - Triple DAT [6-1-17] MicroTech - MasterMaker [6-1-18] Angela Schmidt & Patrick Ohly - MakeCD [6-1-19] Liquid Audio Inc. - Liquid Player [6-1-20] Jörg Schilling - cdrecord [6-1-21] Prassi Software - CD Rep and CD Right [6-1-22] Zittware - CDMaster32 [6-1-23] Dieter Baron and Armin Obersteiner - CD Tools [6-1-24] PoINT - CDwrite [6-1-25] PoINT - CDaudio Plus [6-1-26] Roxio - Easy Media Creator (was Easy CD Creator Deluxe "ECDC") [6-1-27] Padus - DiscJuggler [6-1-28] Ahead Software - Nero [6-1-29] CharisMac Engineering - Discribe [6-1-30] István Dósa - DFY$VMSCD [6-1-31] RSJ Software - RSJ CD Writer [6-1-32] James Pearson - mkhybrid [6-1-33] JVC - Personal Archiver Plus [6-1-34] Roxio - Jam [6-1-35] Pinnacle Systems - InstantCD/DVD (was VOB) [6-1-36] Sony - CD Architect [6-1-37] Eberhard Heuser-Hofmann - CDWRITE [6-1-38] CeQuadrat - JustAudio! [6-1-39] Digidesign - MasterList CD [6-1-40] Thomas Niederreiter - X-CD-Roast [6-1-41] Jesper Pedersen - BurnIT [6-1-42] Jens Fangmeier - Feurio! [6-1-43] Iomega - HotBurn [6-1-44] DARTECH, Inc - DART CD-Recorder [6-1-45] Interactive Information R&D - CDEveryWhere [6-1-46] DnS Development - BurnIt [6-1-47] Andreas Müller - CDRDAO [6-1-48] Tracer Technologies - (various) [6-1-49] SlySoft - CloneCD [6-1-50] IgD - FireBurner [6-1-51] Jodian Systems & Software - CDWRITE [6-1-52] Erik Deppe - CD+G Creator [6-1-53] Micro-Magic - CD Composer [6-1-54] Earjam, Inc. - Earjam IMP [6-1-55] Emagic - Waveburner [6-1-56] Zy2000 - MP3 CD Maker [6-1-57] Integral Research - Speedy-CD [6-1-58] Desernet Broadband Media - Net-Burner and MP3-Burner [6-1-59] Stomp, Inc. - Click 'N Burn [6-1-60] Steinberg Media Technologies - Clean! plus [6-1-61] Enreach - I-Author for VCD/SVCD [6-1-62] VSO Software - Blindread/Blindwrite [6-1-63] Microsoft - Windows XP [6-1-64] An Chen Computers - CD Mate [6-1-65] E-Soft - Alcohol [6-1-66] Stomp Inc. - RecordNow MAX [6-1-67] James Mieczkowski - Cheetah CD Burner [6-1-68] Blaze Audio - RipEditBurn [6-1-69] Acoustica, Inc. - MP3 CD Burner [6-1-70] MagicISO, Inc. - MagicISO [6-1-71] Simone Tasselli - Burn4Free [6-1-72] Sonic Solutions - Record Now! [6-1-73] Freeridecoding - BurnAgain [6-1-74] PowerKaraoke - Power CD+G Burner, PowerKaraoke [6-2] What other useful software is there? [6-2-1] Optical Media International - Disc-to-Disk [6-2-2] Gilles Vollant - WinImage [6-2-3] Asimware Innovations - AsimCDFS [6-2-4] Steven Grimm - WorkMan [6-2-5] Cyberdyne Software - CD Worx [6-2-6] Arrowkey - CD-R Diagnostic [6-2-7] DC Software Design - CDRCue Cuesheet Editor [6-2-8] Astarte - CD-Copy [6-2-9] Frank Wolf - CDR Media Code Identifier [6-2-10] Logiciels & Services Duhem - MacImage [6-2-11] Erik Deppe - CD Speed 2000 [6-2-12] Andre Wiethoff - Exact Audio Copy (EAC) [6-2-13] Earle F. Philhower, III - cdrLabel [6-2-14] Adobe - Audition (formerly Cool Edit) [6-2-15] Elwin Oost - Burn to the Brim [6-2-16] Mike Looijmans - CDWave [6-2-17] ECI - DriveEasy [6-2-18] Jackie Franck - Audiograbber [6-2-19] High Criteria - Total Recorder [6-2-20] Smart Projects - IsoBuster [6-2-21] GoldWave Inc. - GoldWave [6-2-22] Naltech - CD Data Rescue [6-2-23] Jufsoft - BadCopy Pro [6-2-24] CDRoller Soft Co. - CDRoller [6-2-25] FlexiMusic - Wave Editor [6-2-26] Nic Wilson - DVD Info Pro [6-2-27] Audacity [6-3] What is packet writing (a/k/a DLA - Drive Letter Access)? [6-3-1] What's UDF? [6-3-2] Do I want to do packet writing? [6-4] What packet writing software should I use? [6-4-1] Roxio - Drag-to-Disc (a/k/a DirectCD) [6-4-2] CeQuadrat - PacketCD [6-4-3] SmartStorage - SmartCD for Recording [6-4-4] Gutenberg Systems - FloppyCD [6-4-5] Pinnacle Systems - InstantWrite (was VOB) [6-4-6] Prassi - abCD [6-4-7] Ahead - InCD [6-4-8] Oak Technologies - SimpliCD ReWrite [6-4-9] NewTech Infosystems, Inc. (NTI) - File CD [6-4-10] Veritas - DLA (Drive Letter Access) [6-4-11] BHA - B's CLiP [6-5] Can I intermix different packet-writing programs? [6-6] I want to write my own CD recording software [6-6-1] PoINT - CDarchive SDK [6-6-2] Golden Hawk Technology (Jeff Arnold) [6-6-3] Gear Software - GEAR.wrks [6-6-4] VOB - CD-Wizard SDK [6-6-5] Dialog Medien - ACDwrite.OCX [6-6-6] ECI - The Engine [6-6-7] NUGROOVZ - CDWriterXP [6-6-8] Ashampoo - DiscForge Plug & Burn [6-6-9] NuMedia Soft - NMSDVD Burning SDK [6-6-10] Sonic Solutions - AuthorScript [6-7] What software is available for doing backups? [6-7-1] Adaptec - Easy-CD Backup [6-7-2] D.J. Murdoch - DOSLFNBK [6-7-3] Dantz - Retrospect [6-7-4] Veritas - Backup Exec [6-7-5] Symantec - Norton Ghost [6-7-6] PowerQuest - Drive Image Special Edition for CD-R [6-7-7] Centered Systems - Second Copy [6-7-8] FileWare - FileSync [6-7-9] Novastor - NovaDISK [6-7-10] Roxio - Take Two [6-7-11] NTI - Backup NOW! [6-7-12] CeQuadrat - BackMeUp LT [6-7-13] Duncan Amplification - disk2disk [6-7-14] Pinnacle Systems - InstantBackup (was VOB) [6-7-15] Microsoft - Backup [6-7-15] Portlock Software - Storage Manager [6-7-16] Willow Creek Software - Backup To CD-RW [6-7-17] TeraByte Unlimited - Image for Windows [6-8] How do I get customer support for bundled recording software? [7] Media [7-1] What kinds of media are there? [7-2] Does the media matter? [7-3] Who manufactures CD-R media? [7-4] Which kind of media should I use? [7-4-1] What's the best brand of media? [7-5] How long do CD-Rs and CD-RWs last? [7-6] How much data can they hold? 650MB? 680MB? [7-7] Is it okay to write on or stick a label on a disc? [7-7-1] Can I write on them? What kind of pen should I use? [7-7-2] Are labels okay? [7-8] How do CD-Rs behave when microwaved? [7-9] What can I do with CD-R discs that failed during writing? [7-10] Where can I find jewel cases and CD sleeves? [7-11] What's "unbranded" CD-R media? [7-12] How do I repair a scratched CD? [7-13] What's this about a Canadian CD-R tax? [7-14] Can I get 80mm (3-inch "cd single") CD-Rs? [7-15] Where can I find CD-ROM business cards and "shaped" CDs? [7-16] Can you tell pressed CDs and silver CD-Rs apart? [7-17] What's the difference between "data" and "music" blanks? [7-18] How do I convert data CD-Rs into "consumer audio" blanks? [7-19] Is translucent media bad? [7-20] How do I destroy CD-R media beyond all hope of recovery? [7-21] Can I recycle old CDs, CD-Rs, and CD-RWs? [7-22] Is there really a fungus that eats CDs? [7-23] How do I clean CD-R and CD-RW discs? [7-24] Are "black" discs different from other discs? [7-25] My disc just shattered in the CD drive! [7-26] How do I tell which side on a silver/silver disc is up? [7-27] How should I handle and store CDs? [7-28] What causes the rainbow effect when looking at the data side? [7-29] Can I print directly on a CD-R? [8] Net Resources and Vendor Lists [8-1] Information resources [8-2] Magazines and other publications [8-3] Net.vendors [8-3-1] Consumer software, hardware, and media [8-3-2] Net.vendors (duplication services and hardware) [8-4] News sources & mailing lists [9] Contributors The last-modified date of each section is shown below the Subject line. The date format used is YYYY/MM/DD. The date stamps were added on 1998/04/06, so you won't find any older than that.
Subject: [0] Introduction Subject: [0-1] Legal noise (disclaimers and copyrights) (2008/05/21) This document is Copyright (C) 1996-2008 by Andy McFadden, All Rights Reserved. All of the content here, except for attributed quoted material, is my original work. Free distribution of the this FAQ is encouraged, as are conversions to HTML or other formats and translation to foreign languages, so long as no content is removed, and additions are clearly marked. (You are not required to retain the Google advertising links.) The plain ASCII text and www.cdrfaq.org HTML versions aren't otherwise restricted, but other conversions might be (the content is free, the presentation or translation might not be). Check with the publisher. The date and version number on the FAQ *are* considered part of the content that must not be removed. I occasionally get messages from people who don't realize that the copy they're reading is more than a year and a half old. Caveat lector: the information here is often derived from Usenet postings, e-mail, and information on web sites. It may well be DEAD WRONG, and you are encouraged to verify it for yourself. I take no responsibility for damaged hardware, CD-Rs turned into coasters or frisbees, time lost, or any other damages you incur as a result of reading this FAQ. Information on specific models of hardware and software is based on *opinions* of other users, not scientific studies. I am not an expert in this (or any other) field. Everything here could be a total malicious lie, and should be treated as such. You have been warned. I don't get paid to plug anybody's software or equipment. The sections on "what XXX should I buy" are not here because I want to sway purchases one way or another, they're here because the questions are asked *a lot*, and the answers are pretty consistent. You are invited and encouraged to investigate the capabilities and reputations of all products. The various product and company names are trademarks of their respective companies. Visit http://www.clari.net/brad/copymyths.html for a mini-FAQ on copyright laws. Subject: [0-2] What does this FAQ cover (and not cover)? (2000/12/24) This document attempts to answer Frequently Asked Questions about Compact Disc Recordable technology and related fields. It was originally developed as a Usenet newsgroup FAQ, and is updated and posted about once a month. The main foci are explaining CD-R technology, describing hardware and software solutions for creating audio CDs and CD-ROMs, and helping people find solutions to common problems. The FAQ is heavily biased toward PCs and computer-based recorders, because that's what I'm most familiar with, but I have made an effort to include useful information for owners of other equipment. I don't anticipate the section on stand-alone audio CD recorders expanding greatly, because they're far simpler to operate than computer-based recorders, and most of the "must know" information about them is more appropriate in an FAQ on stereo systems or studio recording. I do try to address deficiencies in Macintosh coverage. I don't usually address questions that can be phrased, "how do I make my software do this?" The answers to those should be in the manual that came with your software. In general, this is a collection of answers to specific questions, not a "how to" guide. I have tried to make the answers easy to understand by an inexperienced user, but if you know absolutely nothing about recording CDs then some sections may be confusing. This is not a newsletter. Actively maintained web sites are a much better source of breaking news than this document, which is updated at most once a month. I also don't try to track moving targets, like CD recorder firmware versions or software versions unless a specific release is especially interesting. Ditto for which recorders work with which packet-writing solutions, or which recorders can overburn. This FAQ does not, and will not, cover DVD, DVD-ROM, DVD-R, DVD-RAM, DVD-RW, DVD+RW, or any of the other formats in the ever-expanding DVD morass. There are other resources on the web for DVD topics. You will not find a lot of detail about "backing up" copy-protected software, or where to find unlock codes or "warez". There are many web sites that explain these matters at length. Subject: [0-3] What's new since last time? (2008/10/09) All sections are tagged with a modification date, so you can see how long ago something was revised. (Some of the sections were written 10 years ago and probably need to be rewritten.) If you want to know *everything* that has changed since last time, you can get a set of "context diffs" from http://www.cdrfaq.org/txtdiffs.zip. Highlights: Removed some vendors, added others. Subject: [0-4] Is the FAQ only available in English? (2006/06/16) There are a few translations available. German, by Carsten Stupka: http://www.dvddemystifiziert.de/cdr/faq.html. Hungarian, by Nagy Szabolcs: http://delfin.klte.hu/~nagysz/cdrgyik/. French, by Marc Kergomard: http://www.lagravuredecd.com/. Russian, by Oleg Nechay: http://members.tripod.com/greatkorzhik/cdrfaq.htm. Italian, by Marzona Simone: http://web.tiscali.it/marzonaontheweb/faq/faq.html. Turkish, by Firat Tarman: http://www.tarman.ws/. At one point there were Dutch, Chinese, Spanish, and some other Italian and German translations, but those were discontinued by their authors. French, German, Italian, Portuguese, and Spanish translations can be done through http://babelfish.altavista.com/translate.dyn. This is an automatic language translator that is HTML-aware. It only translates the first part of each document, so it's not entirely helpful if you just want to read a translation, but it may make doing a full translation much easier. (The translation is pretty good for an automatic translator, but is still pretty rough. I don't want to post a translation that is inaccurate or misleading, so I'm not going to run the FAQ parts through babelfish automatically.) If you're interested in translating this FAQ, you are welcome to do so, but please respect the amount of work that I and others have put into it. Don't strip out sections, remove author attributions, or hide the revision date of the document. I don't think the terms in section (0-1) are terribly restrictive. If, for whatever reason, you can't keep up with every update of the English version, that's fine; all I ask is that you include a link to the www.cdrfaq.org version, so that the current information is easily locateable. (Some commonly updated things, like the list of recorders in section (5-1), don't need much translation.) If you don't want to translate a particular section, just leave it in English. If you want to start with an HTML version, use the pages from http://www.cdrfaq.org/. If you prefer to do the translation on a text document, and you're converting to an iso-latin language, the "faq2html" converter that I use can be found in the "downloads" section on http://www.fadden.com/. If you do a translation, let me know and I'll put the URL here. Subject: [0-5] Appropriate use of the newsgroups (1998/04/06) This FAQ covers the three newsgroups in the comp.publish.cdrom hierarchy, one for software, one for hardware, and one for multimedia. The names of the newsgroups imply that the intended topics are related to publishing material on CD-ROMs, but the current discussions cover most everything related to CD-Recordable devices. Here are a few guidelines. These aren't hard and fast rules -- nobody died and put me in charge of making the rules -- but if you're not sure what the appropriate subject matter is then this may be helpful. news:comp.publish.cdrom.hardware is the most popular of the groups. Appropriate material includes questions about past, current, and future CD-R devices. Asking for installation help or advice on what to buy is appropriate, as are questions about related hardware like SCSI adapters and CD-ROM drives. Some related newsgroups are: news:comp.sys.ibm.pc.hardware.cd-rom news:comp.sys.ibm.pc.hardware.storage news:comp.sys.ibm.pc.hardware.systems news:alt.comp.periphs.cdr news:comp.periphs.scsi news:alt.cd-rom news:linux.apps.cdwrite news:comp.publish.cdrom.software is for discussions about software used to prepare material for and create CDs and CD-ROMs. Questions about how to do things with a specific piece of software belong here, as do "the CD-R software from XXX won't recognize my drive", and "does a program exist that does YYY". Some related newsgroups are: news:alt.cd-rom news:linux.apps.cdwrite news:comp.publish.cdrom.multimedia is for discussions about creating multimedia products on CD-ROMs. Questions about multimedia authoring software belong here, as do most production-type questions, e.g. "where can I go to get my CD pressed with jewel cases and glossy inserts?" Related newsgroups are: news:comp.multimedia news:rec.video.desktop news:rec.video.professional news:rec.photo.digital news:misc.education.multimedia Please try to keep cross-posting to a minimum. Broadcasting questions to 3 or 4 related newsgroups will increase the noise level and probably won't get you more answers. Some general rules apply to all of the comp.publish.cdrom.* groups: (1) Piracy of CD-ROM software or CDs: CD recorders can be used to make copies of copyrighted material, and while backups of data are legal, making or accepting copies from others most likely isn't. Whatever your opinion of the matter, software piracy and other copyright violations are illegal in most countries in the world, so requests and/or advertisements for pirated material should be kept off the newsgroup. Also, please don't start or participate in a debate about whether or not software piracy is bad. There have been hundreds of such debates over the past several years, and the only thing that either side has managed to prove is that piracy debates are a tremendous waste of time. (2) Personal CD-R hardware and software sales: strictly speaking, these groups aren't appropriate for selling off your old hardware or software. Such things are best left in misc.forsale.computers.*, ba.market.computers, and related groups. Since many readers are in the market for new hardware, a limited number of clearly marked articles are tolerated. The common Usenet convention is to use "FS: HP4020i $400 obo" for "For Sale" messages and "WTB: HP4020i" for "Want To Buy" messages. (3) CD-R product advertising: these groups by their nature are somewhat commercial. Many readers are in the market for new hardware or CD-R media, and for this reason a *limited* amount of retail/wholesale advertising is tolerated but discouraged. If you *clearly* mark your postings as advertisements, you will get relatively few complaints. Posting frequent and useless followups just to broadcast your 20-line signature will get you flamed and subsequently ignored. Feel free to send mail to people who post questions about product pricing and availability, but please don't create mailing lists and broadcast to everyone who posts. (4) Other advertising: while it's certainly the case that most or all of the readers have a CD-ROM drive on a computer, the same could be said of almost every person reading news from a home computer today. Please keep ads in newsgroups that are more appropriate. Advertising the latest educational, game, or adult CD is inappropriate for these groups, as are "hot new Cyrix 686 PC" posts. Subtle attempts to advertise web sites ("golly, this looked really neat, so I thought I'd tell everyone") are more obvious than you might think. (5) Spam: you cannot make money fast. That's life, get used to it. If the message involves putting your name at the top of a list of 5 or 10 people, don't post it. If it has an 800 or 888 number that a reader would call to hear more about your unique business opportunity, don't post it. (6) Job postings: looking for job candidates on these newsgroups is a tolerated but generally futile exercise. Most of the readers are looking for or offering help on CD-Rs, not searching for a job. Try one of the other groups, like misc.jobs.offered. (7) Binaries: as with most Usenet newsgroups, posting binary files (large or small) is inappropriate. If you want to make a binary file available to Usenet readers, send it to an appropriate alt.binaries newsgroup, and just post a pointer to it in the other group(s). One final note: bear in mind that these groups are read by people all over the world. If you're looking for local retailers, be sure to specify what "local" is for you. Posting in English is the best way to ensure that you will get a response, but the readership is diverse enough that you will likely get a reply no matter what language you use. If you want to quote prices, specify the currency to avoid confusion (e.g. US$300 or CAN$300 or Y30000 or ...). Subject: [0-6] I'm having trouble, how do I ask for help? (2002/12/20) The first thing to do is look at the web pages for the products you're using. Sometimes there will be software or firmware updates, or pages with information on common problems. Doing a web search or scanning through news archives on servers like Google Groups (http://www.google.com/) will often turn up relevant material. If you don't find anything, calling or sending an e-mail message to the technical support department for the product that is giving you trouble is a good second step. If you want to contact other users, posting a message to one of the Usenet newsgroups is a reasonable thing to do. You will get faster, more accurate responses to questions if you include enough detail in your mail message or news posting. For most problems having to do with recording, you need to specify: (1) Platform. PC, Mac, Sun, whatever. (2) Operating system, with version. Win95, Win98, WinNT3.5, WinNT4, etc. Mention any interesting goodies, e.g. IE4 Active Desktop. (3) CD-R brand, model, and firmware revision, e.g. "Yamaha CDR-102 v1.00". (4) Other relevant hardware details. If the recorder comes in SCSI and IDE or parallel-port versions, specify which you were using, and what sort of interface was used (e.g. "SCSI, Adaptec 2940U"). For SCSI and IDE device problems, listing the other devices connected to the same interface is a good idea. (5) Software in use, including version numbers, e.g. "Easy-CD Pro 95 v1.2". (6) Brand of media. Be sure to specify CD-R or CD-RW. (7) What were you trying to do? What specific steps did you take to go about it? Have you tried anything to correct the problem, and if so, what were the results? (8) Specific error messages seen. Write down *exactly* what it says, and any numeric error codes along with it. Be sure to write down what it *said*, not what you think it *meant*. Add your interpretation of events only after you've gotten all the details down. Try to include any details which you think might be relevant. Take the time to organize your report so that it is easy to understand. And PLEASE check this FAQ for the answers first! Much of the volume on the newsgroups is from people whose questions are already answered here. Subject: [0-7] Spelling and name conventions (1999/07/22) Whenever possible, the FAQ tries to use the correct spelling and terminology. Errors should be reported to the FAQ maintainer, but bear in mind that I don't modify the contents of quoted material, the names of products, or the titles of articles and web pages. Some common mistakes are: (1) Writing "CDROM" instead of "CD-ROM". It should be CD-ROM, CD-R, CD-RW, and CD-DA, not CDROM, CDR, CDRW, CDDA. (2) Writing "disk" instead of "disc". The words have the same meaning, but are spelled differently in different countries, just like "color" and "colour". By convention, CDs are called "discs", while hard drives and floppies are called "disks". "Disc-to-disc" copies are different from "disk-to-disc" and "disc-to-disk" copies! (3) Referring to a sector as a "frame". On a CD, the basic allocation unit visible outside the firmware is the 2352-byte sector (sometimes called a "block"). A "frame" is a structure at a lower level. There are 24 bytes in a frame, and 98 frames in a sector (24*98 = 2352). Even the SCSI-3 MMC specification gets this one wrong. Subject: [0-8] Can I advertise on the FAQ pages? (2005/02/07) Since its inception, the FAQ has been made available, in its entirety, free of charge. For nearly nine years, this was done without any overt advertising. This was made possible in large part by Katherine Cochrane and Andy Rubin, who provided free web hosting on cd-info.com and spies.com, respectively. The FAQ was using over 1GB of bandwidth per day at its peak, occasionally exceeding 2GB per day, so hosting the FAQ was not for the faint of heart. The free web hosting days came to an end in January 2005, so I decided that the FAQ should try to pay its own way. I'm currently using Google's advertising service, because Google's ads tend to be tasteful and relevant to readers. It's also easy for me to manage. The ads themselves are chosen by Google based on some criteria I have no control over, so please do not assume that I endorse the ads or vendors in any way. The text version posted to the newsgroups doesn't cost me anything to distribute, so no ads will be found there. Only the cdrfaq.org version has advertising. In an effort to keep the FAQ fair and impartial, I have never accepted direct advertising, mutual linking, or links with affiliate IDs. Vendors with relevant products can have URLs added to appropriate sections of the FAQ, simply by asking. Products that solve specific problems, such as recovering data from damaged discs, repairing scratches, or removing pops and clicks from digitized audio tracks, will be listed under the appropriate topic. CD recording software and hardware vendors can get their own sub-section. Vendors that don't fit in a specific category will be listed in section (8). Subject: [0-9] Can you mail the FAQ to me? (2007/01/26) When the FAQ was originally written there were people who had e-mail but no web access. Those days are pretty much over, so the answer to this question is "no". You used to be able to get it from mail-server@rtfm.mit.edu, but the MIT site stopped accepting updates in mid-2006.
Subject: [1] Simple answers to simple questions (1998/04/06) These are intended to be brief (if somewhat incomplete) answers to basic questions. More detailed information can be found later in the FAQ. For example, section (1-5), "How much can they hold?", is answered in far more detail in section (7-6). Subject: [1-1] What's CD-R? CD-RW? (1999/12/19) CD-R is short for "CD-Recordable". Recordable CDs are WORM (Write Once, Read Multiple) media that work just like standard CDs. The advantage of CD-R over other types of optical media is that you can use the discs with a standard CD player. The disadvantage is that you can't reuse a disc. A related technology called CD-Rewritable (CD-RW) allows you to erase discs and reuse them, but the CD-RW media doesn't work in all players. CD-Rewritable drives are able to write both CD-R and CD-RW discs. All CD recorders can read CDs and CD-ROMs, just like a standard CD-ROM drive. Subject: [1-2] Are they identical to normal CDs? (2005/01/03) CD-ROMs and music CDs you commonly find in stores are pressed from a glass mold. CD-Rs are burned with a laser. They may look different (often green, gold, or blue instead of silver), they're less tolerant of extreme temperatures and sunlight, and they're more susceptible to physical damage. Whether CD-Rs or pressed CDs last longer is difficult to answer. While they're not physically identical, they work just the same. Some CD players and CD-ROM drives aren't as good at reading CD-R and CD-RW discs as they are at reading pressed CDs, but by and large they work just fine. By the way, you can't record on pressed discs, so you might as well throw out all those AOL CD-ROMs you've been accumulating (or try one of the suggestions in section (7-9)). Buying a bunch of old CDs in the hopes of writing new stuff onto them is a bad idea. For similar reasons you can't record on DVD media, not even DVD-R and DVD+RW, unless your drive explicitly supports the DVD formats. You have to buy blank CD-R or CD-RW media. Subject: [1-3] Can I create new audio and data CDs? (2001/11/09) Yes. You can create CD-ROMs from data on your hard drive, and you can create new audio CDs from anything you can record into a WAV or AIFF sound file. With an audio-only CD-Recorder, which hooks up to your stereo system instead of your computer, you can record directly from CD, cassette, DAT, or whatever. The CD-ROMs you produce will play in ordinary CD-ROM drives, and the audio CDs you create will work in your home or car CD player. Writing to CD-Rs and CD-RWs requires a CD recorder. You can't write CDs with an ordinary CD-ROM drive. One of the more popular things to do with a CD recorder is make copies of old cassettes and LPs. See section (3-12) for information about this. Subject: [1-4] Can I use it to copy my CDs? (1998/04/06) Yes, both audio and data CDs can be duplicated. You can even create audio CDs that are compilations of other audio CDs (perhaps a personal "best of" disc). Bear in mind that most CDs are protected by copyright laws. Subject: [1-5] How much can they hold? (2004/02/20) Commonly available blanks hold either 74 or 80 minutes of music, which works out to 650MB and 700MB of data, respectively. See section (7-6) for more info. Subject: [1-6] Can I just copy files onto a CD-R like I would to a floppy? (2003/03/11) Yes and no. The process can be a bit more involved than that, and requires software that (usually) comes bundled with the drive. With "packet writing" software, and a recorder that supports it, you can treat a CD-R or CD-RW disc like a floppy. On a CD-R you can only write to each part of the disc once, so deleting files doesn't free up any space. There are other limitations as well. With more traditional software -- necessary if you want broad compatibility -- you usually end up writing everything to the disc all at once. When you're doing the writing you can't interrupt the drive, and you can't reclaim the space you've used. If you want to write your files in smaller bunches, you lose a fair bit of space every time you stop and start again. Subject: [1-7] What can you tell me about DVD, DVD-R, DVD-RAM, DVD-RW, etc? (2002/12/20) Nothing. This FAQ is about CD-R and CD-RW, and only crosses over into DVD when the two technologies rub up against each other. To learn more about DVD, see section (2-14) and read the DVD FAQ at http://www.dvddemystified.com/dvdfaq.html. For DVD recorders, check out the Usenet newsgroup alt.video.dvdr and perhaps rec.video.dvd.tech. Subject: [1-8] Can I copy DVDs with a CD recorder? (2001/04/20) Not directly. CD and DVD are very different formats, so you can't write DVDs with your CD recorder. You may be able to convert the contents into a lower-quality format though. Be wary of scams. See section (3-49). There are devices now that can record both DVD-R and CD-R. Those are usually advertised as "DVD recorders", not "CD recorders". Subject: [1-9] What's the cheapest recorder and best place to buy media? (1999/02/07) I don't know. I don't track prices. There are web sites dedicated to finding the lowest prices, and you can do a little research with a web browser, starting perhaps with the vendors listed in section (8-3). Subject: [1-10] Can I get step-by-step installation and use instructions? (1999/02/07) Yes, from the manual that comes with your recorder and software. There's no information of this type in the FAQ because there are far too many permutations of hardware and software, and the instructions would have to be updated with every new release of the software. Subject: [1-11] Can I download MP3s from the Internet and make an audio CD? (1999/12/18) Yup. You can download MP3s, write them to a CD, and play it in anything that handles audio CDs. In fact, many of the popular CD recording programs will decode the MP3s for you. It's also possible to take songs from a CD and convert them to MP3s for use in an MP3 player. Section (3-27) has more details. Subject: [1-12] What does this term mean? Is there a glossary? (2007/08/08) There are some good glossaries on the web, though they're becoming harder to find. Here are a few. Adaptec (hosted by osta.org): http://www.osta.org/technology/cdr.htm ProAction Media: http://www.proactionmedia.com/cd_dvd_glossary.htm Leo Pozo's Complete CD and DVD Glossary: http://web.archive.org/web/20040407160109/http://www.cdpage.com/Compact_Disc_Glossary/glossarym.html Subject: [1-13] Do I need "music" blanks to record music? (2002/10/12) You only need "music" blanks if you have a "consumer" stand-alone audio CD recorder. If you have a recorder attached to your computer or a "professional" deck then the "music" blanks will work no better or worse than "data" blanks. See section (7-17) for details. Subject: [1-14] How do I learn more? Is there a good book for beginners? (2002/10/04) This FAQ contains a great deal of information, but it's geared toward answering specific questions rather than providing a general education. Some of the other net resources are more like a tutorial than a Q&A list, and may provide a better starting point. Mike Richter has a primer on CD-R at http://www.mrichter.com/. Roxio has some good information at http://www.roxio.com/en/support/. If you're new to CD recording and are feeling a little lost, you may want to buy a book on the subject. Try one of these: - _CD Recordable Solutions_ by Martin C. Brown. Software emphasis is on Roxio Easy CD Creator, Roxio Toast, and "cdrecord" for Linux. Visit http://www.muskalipman.com/cdrsolutions/index.html. - _CD and DVD Recording for Dummies_ by Mark L. Chambers. Has a section on hardware installation. Software emphasis is on Roxio Easy CD Creator, Roxio Toast, and Apple iDVD. - _The Complete Idiot's Guide to Creating Your Own CDs_ by Terry Ogletree et.al. Software emphasis is on Roxio Easy CD Creator and NTI CD-Maker. Sample pages, including complete tables of contents, can be found for all of the above at http://www.amazon.com/. Subject: [1-15] Why is this FAQ so far out of date? (2000/05/25) You may be reading an out-of-date copy of the FAQ. Some sites like to make a copy of the FAQ with the version, date, and contact information stripped off the top (in violation of section (0-1)), which makes it hard to tell when it was last updated. The FAQ is updated about once a month, and the most recent version is always available from http://www.cdrfaq.org/. If you are reading the current version, either the section hasn't been updated in a while (check the date in the section), or something has slipped past me. If you want news articles updated daily, try the sites in section (8-4).
Subject: [2] CD Encoding (1998/04/06) CD fundamentals. Subject: [2-1] How is the information physically stored? (2004/02/20) From _The Compact Disc Handbook, 2nd edition_ by Ken Pohlmann, 1992 (ISBN 0-89579-300-8): "Write-once media is manufactured similarly to conventional playback-only discs. As with regular CDs, they employ a polycarbonate substrate, a reflective layer, and a protective top layer. Sandwiched between the substrate and reflective layer, however, is a recording layer composed of an organic dye. .... Unlike regular CDs, a pre-grooved spiral track is used to guide the recording laser along the spiral track; this greatly simplifies recorder hardware design and ensures disc compatibility." Your basic CD-R is layered like this, from top to bottom: [optional] label [optional] scratch-resistant and/or printable coating UV-cured lacquer Reflective layer (24K gold or a silver alloy) Organic polymer dye Polycarbonate substrate (the clear plastic part) Yes, it's real gold in "green" and "gold" CDs, but if you hold a CD-R up to a light source you'll notice that it's thin enough to see through (the gold layer is between 50 and 100nm thick). Something to bear in mind is that the data is closest to the label side of the CD, not the clear plastic side that the data is read from. If the CD-R doesn't have a hard top coating such as Kodak's "Infoguard", it's fairly easy to scratch the top surface and render the CD-R unusable. A pressed CD has raised and lowered areas, referred to as "lands" and "pits", respectively. A laser in the CD recorder creates marks in the disc's dye layer that have the same reflective properties. The pattern of pits and lands on the disc encodes the information and allows it to be retrieved on an audio or computer CD player. See section (2-43) for specifics. Discs are written from the inside of the disc outward. On a CD-R you can verify this by looking at the disc after you've written to it. The spiral track on a 74-minute disc makes 22,188 revolutions around the CD, with roughly 600 track revolutions per millimeter as you move outward from the lead-in (23mm from the center) to the outer edge at 58mm. If you "unwound" the spiral, it would be about 5700 meters (3.5 miles) long. The construction of a CD-RW is different: [optional] label [optional] scratch-resistant and/or printable coating UV-cured lacquer Reflective layer (aluminum) Upper dielectric layer Recording layer (phase change film, i.e. the part that changes form) Lower dielectric layer Polycarbonate substrate (the clear plastic part) See the net references section for pointers to more data (especially http://www.cd-info.com/). You can find some nice drawings at http://www.pctechguide.com/09cdr-rw.htm. The various pages connected to http://www.chipchapin.com/CDMedia/cdda5.php3 have some computations on disc parameters. The Philips document "Principles of Phase Change Recordings" at http://www.licensing.philips.com/information/cd/rec/ has some nice drawings and a very detailed explanation of how CD-RW works. Subject: [2-2] What is XA? CDPLUS? CD-i? MODE1 vs MODE2? Red/yellow/blue book? (2002/12/20) A quick summary of standards and commonly used identifiers: Red Book = physical format for audio CDs (a/k/a CD-DA) Yellow Book = physical format for data CDs Green Book = physical format for CD-i Orange Book = physical format for recordable CDs Part I = CD-MO (Magneto-Optical) Part II = CD-WO (Write-Once; includes "hybrid" spec for PhotoCD) Part III = CD-RW (ReWritable; originally called CD-E) White Book = format for VideoCD (often written "VCD") Blue Book = CD Extra (occasionally used to refer to LaserDisc format) CD Extra = a two-session CD, 1st is CD-DA, 2nd is data (a/k/a CD Plus) MODE-1 = standard 2048-byte Yellow Book sectors, with error correction MODE-2 = 2336-byte sectors, usually used for CD-ROM/XA CD-ROM/XA = eXtended Architecture; CD-ROM/XA MODE-2 defines two forms: FORM-1 = 2048 bytes of data, with error correction, for data FORM-2 = 2324 bytes of data, no ecc, for audio/video ISO-9660 = file layout standard (evolved from High Sierra format) Rock Ridge = extensions allowing long filenames and UNIX-style symlinks CD-RFS = Sony's incremental packet-writing filesystem CD-UDF = industry-standard incremental packet-writing filesystem CD-Text = Philips' std for encoding disc and track data on audio CDs CD-ROM/XA is an extension to the Yellow Book Mode 2 standard. It was intended as a bridge between CD-ROM and CD-i (Green Book). See http://www.licensing.philips.com/ if you want to buy copies of the standards. They're not cheap! You can download some of them from http://www.ecma-international.org/. ECMA-119 describes ISO-9660, and ECMA-130 sounds a lot like "yellow book" if you say it slowly. For SVCD, see http://www.iki.fi/znark/video/svcd/overview/. The discs are a modified White Book format, using a 2x player and variable bit rate MPEG-2 instead of MPEG-1 at 1x like VCD. For HDCD, see http://www.hdcd.com/. The discs are in Red Book format, but the low bit of the audio has additional information encoded in it. They sound good on a standard CD player, and better on an HDCD player. SACD isn't really a CD format. It can have a Red Book compliant layer that is read by standard CD players, but to get the high-fidelity benefits you need a special player. Subject: [2-3] How do I know what format a disc is in? (2001/07/09) You can usually tell by looking at the packaging and/or the disc itself: - CD-DA discs will have a "Compact Disc Digital Audio" logo. - CD+G discs will have the words "CD Graphics" (and perhaps even CD-EG "Extended Graphics"). - CD-i discs will have a "Compact Disc Interactive" logo. - VideoCD discs will have a "Compact Disc Digital Video" logo and/or the words "VideoCD". - PhotoCD discs will most likely say "Kodak PhotoCD" on them. - SVCD discs have a "Super Video CD" logo (the words "Super Video" under the standard CD logo). The discs use one of the standard CD-ROM formats. - DVCD discs say "DVCD"?? [ can't find much info about DVCD ] - HDCD (High Definition Compatible Digital) have an "HDCD" logo. See http://www.hdcd.com/. The discs appear to use the standard Red Book format. - SACD (Super Audio Compact Disc) is relatively new. The discs can have two layers, one of which is in Red Book audio format, the other in a DVD-like format offering higher fidelity. - DTS (Digital Theater Surround) CDs are just like normal CDs, but use DTS encoding instead of PCM. See (2-34). VideoCD is different from CD-Video (a/k/a "Compact Disc Video", or CD-V). CD-V is an analog format, like LaserDisc, and the video can't be viewed with a CD-ROM drive. There are a few references to Compact Disc MIDI, or CD-MIDI. See (4-46) for some comments on High Speed CD-RW. Subject: [2-4] How does copy protection work? (2002/04/01) Copy protection (sometimes erroneously referred to as "copyright protection") is a feature of a product that increases the difficulty of making an exact duplicate. The goal is not to make it impossible to copy -- generally speaking, that can't be done -- but rather to discourage "casual copying" of software and music. The goal is *not* to conceal information from prying eyes; see section (3-19) for information on encrypting data on a CD-ROM. A separate but related issue is "counterfeit protection", where the publisher wants to make it easy to detect mass-produced duplicates. An example of this is Microsoft's placement of holograms on the hubs of their CD-ROMs. There are full CD pressing plants dedicated to creating counterfeit software (the worst offender being mainland China), so this is a serious concern for the larger software houses. Copy protection on CD-ROMs used to be rare, but as the popularity of CD recorders grew, so did the popularity of copy protection. A large percentage of games released in the past few years have been protected. A more recent innovation is copy protection for audio CDs, inspired by the rise of MP3 trading over the Internet. This is more difficult to do, because the protection must allow correct behavior on a CD player but altered playback when being read by a CD-ROM drive. The best that can be accomplished is to force the user to play the music in an analog format and then re-digitize it, resulting in an imperfect reproduction. The article at http://news.cnet.com/news/0-1005-201-7320279-0.html is a nice introduction to the issues. Some people have questioned whether copy protection is legal. In some countries it may not be. In the USA, the law allows "fair use" of copyrighted material, but does not require that the content provider make it easy for you to do so. So while making a copy of a song for your own private use may be legal, there is nothing in the law that requires the publisher to make the material available in an unprotected format. Copy protection has been around for many years -- some of the schemes employed on the Apple II were remarkably elaborate -- and has never been challenged on legal principle. See http://overclockers.com/tips907/ for an article about why "fair use" is a legal right rather than a constitutional right in the USA, and what that means to you. The article also has some interesting quotes from the courts regarding the DMCA and DeCSS, notably this one: "We know of no authority for the proposition that fair use, as protected by the Copyright Act, much less the Constitution, guarantees copying by the optimum method or in the identical format of the original." In other words, arguing that "fair use" means the publisher must allow you to make a perfect digital copy (as opposed to a lower-quality digital or analog copy) is without merit. The next sections discuss data and audio individually. Subject: [2-4-1] ...on a data CD-ROM? (2002/12/09) There are several approaches. An article with a good overview of some popular protection technologies can be found at http://www.tomshardware.com/storage/02q2/020617/index.html. Another source is the "CD Protections" articles on http://www.cdmediaworld.com/hardware/cdrom/cd_protections.shtml. For anyone interested in protecting their own discs: don't bother. Copy protection, on the whole, does not work. If you have a major application, such as a game or CAD package, you may want to consider one of the commercially licensed schemes listed later, or (heaven forbid) the use of a dongle. In general, though, if the disc can be read, then the contents can be copied. If you don't want somebody to make a copy of your stuff, then you'd better encrypt it (3-19). A simple and commonly seen technique is to increase the length of several files on the CD so that they appear to be hundreds of megabytes long. This is accomplished by setting the file length in the disc image to be much larger than it really is. The file actually overlaps with many other files. So long as the application knows the true file length, the software will work fine. If the user tries to copy the files onto their hard drive, or do a file-by-file disc copy, the attempt will fail because the CD will appear to hold a few GB of data. (In practice this doesn't foil pirates, because they always do image copies. And, no, none of the standard software provides a way to create such discs.) One possible implementation, given sufficient control over the reader and mastering software, is to write faulty data into the ECC portion of a data sector. Standard CD-ROM hardware will automatically correct the "errors", writing a different set of data onto the target disc. The reader then loads the entire sector as raw data, without doing error correction. If it can't find the original uncorrected data, it knows that it's reading a "corrected" duplicate. This is really only viable on systems like game consoles, where the drive mechanism and firmware are well defined. This can be defeated by doing "raw" reads. A more sophisticated approach is to write special patterns of data to the disc. The stream of data that results, after EFM encoding, is difficult for some recorders to reproduce successfully, apparently because they don't choose correct values for the merging bits. This is often referred to on web sites as "writing regular EFM patterns" or "weak sectors". See section (2-43) for details on EFM. A less sophisticated -- and no longer effective -- method is to press a silver CD with data out beyond where a 74-minute CD can write. Copying the disc used to require hard-to-find CD-R blanks, but now it's easy to use an overburned 80-minute disc (sections (3-8-1) and (3-8-3)). The approach some PC software houses have taken is to use nonstandard gaps between audio tracks and leave index marks in unexpected places. These discs are uncopyable by most software, and it may be impossible to duplicate them on drives that don't support disc-at-once recording (see section (2-9)). With the right reader and software, though, this isn't much of a problem either. A method that enjoyed some popularity was non-standard discs with a track shorter than 4 seconds. Most recording software, and in fact some recorders, will either refuse to copy a disc with such a track, or will attempt to do so and fail. A protected application would check for the presence and size of the track in question. Some recorders may succeed, however, so this isn't foolproof. (In one case, a recorder could write tracks that were slightly over three seconds, but refused to write tracks that were only one second. There may be a limit below which no recorder will write.) In such cases, the pirates need to remove the explicit check from the software itself. Putting multiple data tracks interleaved with audio tracks on a CD will confuse some disc copiers. However, it's difficult to actually use the data on those additional tracks. Sometimes the copy of a disc will have a different volume label. This usually only happens with file-by-file copies, not disc image copies, so checking the disc name is marginally useful but not very effective. Modifying the TOC so that the disc appears to be larger than it really is will convince some copy programs that the source disc is too large. Some of the fancier technologies use non-standard pit geometry that cause players to read the data differently on consecutive attempts. Sometimes the player sees a "1", sometimes a "0". If, when reading the track, the CD-ROM drive sees different data each time, the software knows that the disc is an original. A duplicate disc will return the same data reliably. (So too will some CD-ROM drives... this technology is not without problems.) Some programs will examine the disc to try to determine if it's a CD-R. This doesn't work on all readers, and it's possible to disguise discs, so this isn't very effective. CloneCD (section (6-1-49)) can copy many copy protected discs without trouble, given the right combination of reader and writer. Its main feature is "raw" reads and writes, which not all drives support. The Laserlok system from http://www.diskxpress.com/ claims to be able to prevent unauthorized disc duplication at a low cost. It can be copied by CloneCD. An unrelated product called LaserLock, from MLS LaserLock International (http://www.laserlock.com/) has similar features. It can be copied by CloneCD. TTR Technology's DiscGuard (http://www.ttr.co.il/ or http://www.ttrtech.com/ claims to be able to write a signature onto pressed CDs and CD-Rs that is detectable by all CD-ROM drives but isn't reproducible without special hardware. A program could use this for copy protection by checking for the presence of the signature, and refusing to run if it's not there. Sony DADC is promoting a similar product called Securom. Some information is at http://www.sonydadc.com/hotnews/secu_fra.htm. Yet another variant is C-Dilla's SafeDisc. They were bought by Macrovision (http://www.macrovision.com/). Their more recent product, SafeDisc 2, was the first to feature "weak sectors". Yet another variant is CD-Cops from Link Data Security (http://www.linkdata.com/). Subject: [2-4-2] ...on an audio CD? (2002/10/21) The challenge here is to create a disc that will play on a standard audio CD player but be difficult to copy or "rip" into an MP3. The techniques making headlines in mid-2001 were developed by Macrovision (2-4-3) and SunnComm (2-4-4). The earliest form of audio CD copy protection was SCMS. This only works on recorders that support SCMS, specifically consumer-grade stand-alone audio CD recorders. "Professional" recorders, and recorders that attach to computers, do not support SCMS. See section (2-25). Some CDs used a damaged TOC (Table of Contents -- see section (2-27)) that confused some CD-ROM drives and ripping software. More recent schemes attempt to modify the audio samples in ways that confuse CD-ROM drives into playing static. The next few sections describe these approaches in detail. A web site at www.fatchucks.com used to have a list of suspected copy-protected discs and some tips on what you can do to let the industry know that copy protection isn't appreciated. The web site appears to be gone, but you can see an archived copy of it here: http://web.archive.org/web/20031002104003/www.fatchucks.com/z3.cd.html Many forms of copy protection violate the CD-DA standard, and so the discs aren't allowed to use the official CD logo art. However, many CDs don't have the logo anywhere, so its absence doesn't prove anything. A paper entitled "Evaluating New Copy-Prevention Techniques for Audio CDs" by J.A. Halderman (available only in PostScript format) can be found at http://crypto.stanford.edu/DRM2002/halderman_drm2002_pp.ps. The paper was submitted to the 2002 ACM Workshop on Digital Rights Management (http://crypto.stanford.edu/DRM2002/prog.html). Incidentally, if you're convinced that record companies and artists are raking in huge piles of cash from every CD they sell, you might want to take a look at an Electronic Musician article that talks about where the money comes from and where it goes. See: http://industryclick.com/magazinearticle.asp?magazineid=33&releaseid=9554&magazinearticleid=132835&SiteID=15 (You may need to use IE; Netscape 4.7 for Linux couldn't view the site.) Interesting figures: only about 16% of CDs sold make enough money for the publishers to break even. The ones that do make enough money have to pay for the rest. For the recording artists, only about 3% sell enough music to get any royalties. With figures like these, it's not surprising that the industry is taking steps to combat piracy. For more news & commentary, see: - http://www.latimes.com/technology/la-000093190nov22.story - http://www.modbee.com/24hour/entertainment/story/183508p-1775112c.html - http://www.siliconvalley.com/docs/news/svfront/cd121701.htm For some messages about Sony's discs that can crash computers, see http://slashdot.org/article.pl?sid=02/04/03/226233&mode=nested. A later article in MacUser noted that the Celine Dion disc _A New Day Has Come_ will lock up iMacs and require physically disassembling parts of the machine to get the disc back out. The article is http://www.macuser.co.uk/macsurfer/php3/openframe.php3?page=/newnews/newsarticle.php3?id=1990 Subject: [2-4-3] ...on an audio CD (Macrovision - SafeAudio) (2001/08/28) In the first part of the year 2000, TTR Technologies announced a product called MusicGuard (http://www.MusicGuard.com/) that claimed to prevent duplication of audio CDs. The product was withdrawn, but the technology has resurfaced in mid-2001 as a product called SafeAudio from Macrovision (http://www.macrovision.com/). The basic idea is to create samples that sound like bursts of static, and scramble the ECC data around to make it look like an uncorrectable error. Audio CD players will interpolate the samples during playback, but CD-ROM drives doing digital audio extraction generally won't. The result is a disc that plays back correctly on a CD player, but won't "rip" or copy correctly on a CD-ROM drive. Some relevant sites and news articles: - http://www.macrovision.com/solutions/newtech/audio/safeaudio.php3 - http://www.newscientist.com/news/news.jsp?id=ns9999998 - http://cnet.com/news/0-1005-200-6604222.html This approach relies on an anachronism of CD-ROM drive construction. There are two ways to play a CD on a computer, one analog, one digital. The analog path sends the audio across a cable connected from the CD-ROM drive to the sound card. Most of the CD player software available on computers works by telling the CD-ROM drive to start playing the CD through the analog cable. (This may not hold true for newer Macintoshes -- it appears Mac OS 9 uses an entirely digital approach. Some recent CD player applications for the PC also do this.) The digital path requires reading the "raw" audio samples off of the disc, possibly modifying the data (e.g. changing the byte ordering) into something appropriate for the sound card, and then writing them to the sound device. Until a few years ago, most CD-ROM drives did this very poorly, in part because the analog and digital data paths were logically distinct in the designers' minds. Audio CDs used the audio path, data CD-ROMs used the digital path, and while you *could* send audio over the digital path there didn't seem to be much value in doing so. (See section (2-15) for some additional notes.) What Macrovision appears to be exploiting is the different handling of uncorrectable errors in audio samples on the digital path vs the analog path. When playing an audio CD in a CD player or CD-ROM drive, the analog path is used. This path deals with uncorrectable (E32) errors by examining the samples that come before and after the error, and interpolating between them. On a scratched-up CD, this means that, while you may not be hearing the exact samples that were originally recorded, you won't notice any glitches because they're smoothed over. This feature is definitely not something you'd want on a data CD-ROM -- interpolating pieces of your spreadsheet is not going to help you. In most CD-ROM drives, reading an audio sector with digital audio extraction is handled the same way that reading a data sector is: uncorrectable errors are left alone. Instead of getting interpolated samples, you get to hear the original, scratched-up audio. This is why some CDs will play back just fine on your computer, but will come out all scratched up when you extract them with the same drive. The errors are there either way, but when using a desktop CD player the errors have been smoothed over by the logic in the analog output path. Some drives may use interpolation during DAE at lower speeds. If so, it should be possible to "rip" a track from a copy-protected disc by reducing the extraction speed to 1x. Some people have suggested that software could be used to perform the interpolation on extracted music, stripping out the bits that the music companies added in. The trouble with this approach is that, once the data has been extracted, the CIRC encoding is no longer visible. It may not be easy to tell where the glitches are. For example, it should be possible to create a low-level but rhythmic distortion that will be noticeable, annoying, and difficult to identify automatically. (It's possible that any software specializing in defeating the copy protection would run afoul of the DMCA (Digital Millenium Copyright Act), and the authors subject to fines and criminal prosecution. Come to think of it, the preceding discussion might be illegal. For more information about the DMCA, see http://www.eff.org/.) How can you get a "clean" copy of a protected disc? There are four basic approaches, in order of least to most desirable: (1) Record directly from the analog outputs of the drive, feeding the sound into a sound card or outboard A/D converter. Some fidelity will be lost when converting from digital to analog and back again, which is what the industry is counting on. (2) It should be possible to play the disc on a CD player with an S/PDIF connector, and get error-interpolated digital output. If played into a digital sound card or a CD recorder with an S/PDIF input, it should be possible to capture an exact copy of the original. Of course, it has to be done at 1x, and the track breaks may have to be added manually, making it a potentially tedious affair. This might be avoidable on a CD-R "dubbing deck", but inexpensive models will add SCMS to the set of things to worry about. Don't forget that generation loss is possible with CDs, especially if you record from CD-Rs (due to their higher BLER rate), so copying to CD-R and then extracting from CD-R requires some care. See section (3-18). (3) Some drives support an extension described in recent versions of the ATA/ATAPI and SCSI MMC specifications. This extension to the "READ CD" command returns a set of flags indicating which bytes in an audio block were not corrected at the C2 level (section (2-17). An audio extraction application with access to this information could do its own interpolation across errors. Some applications already make some use of this feature; see http://www.feurio.com/English/faq/faq_vocable_c2error.shtml. The "drive check" feature of cdspeed (section (6-2-11)) reports on whether or not a drive is capable of returning "C2 pointers". (4) A CD-ROM drive with logic that interpolates uncorrectable errors during DAE would allow copying and ripping with no additional effort required. The success or failure of audio CD copy protection hinges upon two factors: how effective is it at preventing "casual copying", and what sort of problems do the legitimate owners of audio CDs encounter when playing their discs? Macrovision claims that their "golden ear" listeners were not able to tell the difference, though the test might be biased if the folks with the shiny lobes were using high-end CD players that did an especially good job of concealing uncorrectable errors. A legitimate technical concern is that the copy protection reduces the effectiveness of the error correction. Because some percentage of ECC is now required for proper playback on a *clean* disc, the odds of scratches and fingerprints causing audible degradation are increased. In practice, if the "static" samples are relatively few and far between, the difference would be statistically insignificant. One last piece of advice: do not assume that any disc that doesn't extract cleanly is copy-protected. There have been many, many postings on message boards from people who think they have found a protected disc, or how some specific piece of software can defeat the protection. Start with the more common reasons: the disc is dirty, the disc was poorly made, your CD-ROM drive is not that great at audio extraction, you're using software that isn't the best. There are many reasons why ripping an audio track might fail. People have been having trouble getting clean audio for years. See section (3-3) for some advice if you're having trouble. Certain web sites (notably cdfreaks.com) have been reporting that a replacement CDFS.VXD will fix everything. However, doing the audio extraction in a VXD instead of an EXE makes no difference. So far, none of the sites that have claimed victory list a single SafeAudio-protected disc that was copied, most likely because -- at the time this was written -- there weren't any discs known to use SafeAudio. (This phenomenon is not unheard-of; Sega's Dreamcast discs were widely reported to be copyable by a means that was quickly determined to be utterly ridiculous.) If the widely-touted CDFS.VXD is in fact a hijacked Plextor driver, then it may well use technique #3 mentioned above, but would only work on a drive that supported the extended READ CD feature. Subject: [2-4-4] ...on an audio CD (SunnComm - MediaCloQ and MediaMax CD3) (2005/12/09) SunnComm (http://www.sunncomm.com/) has a product called "MediaCloQ". It was used to protect the album _A Tribute to Jim Reeves_ by Charley Pride in mid-2001. The results were inconclusive: clean versions of the tracks appeared on the net, but SunnComm claimed they came from an unprotected disc released on Australia. Their plan was to alleviate "fair use" concerns by allowing users to download MP3 versions of the songs after they registered the original. Some articles: - http://news.cnet.com/news/0-1005-200-5924584.html - http://www.zdnet.com/zdnn/stories/news/0,4586,5082954,00.html - http://news.cnet.com/news/0-1014-201-7311791-0.html Some early stories indicated that BMG Entertainment was considering the use of this product. Sony-BMG did eventually use SunnComm products on several CDs. See http://www.zdnet.com/zdnn/stories/news/0,4586,5094925,00.html. The idea behind this protection is to make it hard for CD-ROM drives to identify the disc as being an audio CD. The disc is multisession, and uses a hacked TOC, so track rippers and disc copiers have trouble dealing with it. SunnComm hasn't publicly stated any details. In August 2001, SunnComm announced v2.0 of their product, but didn't provide specific details. In mid-2003, SunnComm announced "MediaMax CD3", a fancier implementation that allows computer users to play the CD through software supplied on the disc. The software installs a memory-resident driver that prevents CD ripping from working on protected CDs. The protection can be foiled on Windows PCs by simply holding down the shift key for several seconds while inserting the CD. See http://www.cs.princeton.edu/~jhalderm/cd3/ for a detailed analysis. SunnComm announced they were going to sue the Princeton researcher, but quickly backed off. In December 2005, following the XCP disaster (see section (2-4-10)), a flaw was discovered in MediaMax v5 that could allow malicious software to gain control of an affected computer. http://sonybmg.com/mediamax/ has a "consumer advisory" regarding the problem, including a list of affected CDs and links to a patch and uninstaller on the sunncomm.com web site. It was subsequently determined that the patch was flawed; see http://news.bbc.co.uk/1/hi/technology/4511042.stm. Some personal notes on SunnComm's protection of the Charley Pride disc, including the steps I took to get a clean copy: The packaging is labeled with the SunnComm logo, and states, "This audio CD is protected by SunnComm(tm) MediaCloQ(tm) Ver 1.0. It is designed to play in standard audio CD players only and is not intended for use in DVD players." However, my DVD player was able to play the disc after overcoming some initial confusion. The disc itself has an unusual construction. There is a heavy band at about the point where the music stops, and thin bands between tracks. These appear to be purely decorative (and, I'm told, increasingly common on non-protected discs). Some images are available on http://www.fadden.com/cdrpics/. A computer running Win98SE with a Plextor 40max CD-ROM drive saw the disc as having two sessions and 16 data tracks. My CD player only saw 15 audio tracks. This feature alone makes the disc difficult to rip or copy, because the software doesn't see any audio tracks, and a CD-R copy would be full of tracks that even a CD player would see as data. Another machine, with a Plextor 12/20 and a slightly different set of software, seemed to have a lot of trouble figuring out what the disc was. It eventually sorted things out, but I get the sense the disc has been tweaked in ways that confuse the drive firmware. I tried using "Session Selector" to select the first session and then access the tracks. This resulted in a Plextor 8/20 CD recorder becoming unusable until a reboot. I'd guess the firmware got confused. The next thing I tried was to crank up CDRWIN v3.7a (section (6-1-7)), and extract some tracks using my Plextor 12/20. No dice -- the display showed 15 unselectable tracks and 1 MODE-2 data track. Next, I tried the "Extract Disc/Tracks/Sectors" function, selected "Extract Sectors", chose "Audio-CDDA (2352)" for the data type, and entered a nice range (0 to 300000, where each audio sector is 1/75th of a second). This choked when trying to read starting at block 173394, so I tried again stopping at 173390. This resulted in a rather large WAV file, which I opened with Cool Edit -- revealing the entire contents of the disc, plain and clear. Playback revealed no audible defects. I believe this worked because the sector extraction function ignores track and session boundaries, and just pulls the blocks straight off. Losing the track markers is annoying, but it's easy to add them back with something like CDWave (section (6-2-16)). (FWIW, this same approach did *not* work for the _My Private War_ disc with the damaged TOC, described in (2-4-2). It would probably not be of help with a SafeAudio disc either.) "zEEwEE" came up with a complicated but enlightening scheme for side-stepping the protection on discs with damaged second TOCs. It has the advantage of allowing you to use standard tools, such as Exact Audio Copy (section (6-2-12)), which keeps the track breaks and can do fancy tricks to get the best extraction quality. The method involves making the outer rim of the disc unreadable to the CD-ROM drive by drawing on it with a dry-erase marker or adding an adhesive sticker. This method, first posted in August of 2001, resulted in a flurry of media attention in May of 2002. Subject: [2-4-5] ...on an audio CD (Midbar Tech - Cactus Data Shield) (2002/02/13) Midbar Tech Ltd (http://www.midbartech.com/) appears to have two different schemes under the "Cactus Data Shield" brand. (The web site shows three now: CDS100, CDS200, and CDS300.) The first uses a non-standard TOC. The position of the lead-out and the length of the last track were tweaked, resulting in a disc that appears to be only 28 seconds long. The alterations didn't confuse all CD-ROM drives, and it has been reported that some Philips CD players couldn't play the discs. BMG Entertainment reportedly tried it and abandoned it. In late 2001, Midbar Tech announced a different approach. A US patent (http://www.delphion.com/details?&pn=US06208598__) describes the invention. The approach appears to involve inserting frames of bogus control information into a relatively constant part of the CD audio stream. During playback, the extra frames are skipped. A disc copy or digital stream on an S/PDIF output will include the bogus frames, and when written to CD-R the extra control information won't be included. The result is bad samples that only appear in copies. News articles: - http://news.com.com/2100-1023-835841.html - http://www.newscientist.com/news/news.jsp?id=ns99991105 - http://www.cnn.com/2001/TECH/ptech/08/08/cd.copy.protection.reut/index.html The difficulty in copying such a disc depends on how the stream of audio samples appears. In news articles the company claims that the scheme can defeat method #2 described in section (2-4-3), in which the S/PDIF connector of a CD player is used to get an error-interpolated digital stream. That suggests that the bogus data doesn't appear as uncorrected data, but rather as valid data that is suppressed on the analog outputs. This would seem to make digital copying difficult, but it would also make any form of digital playback impossible. No specific disc titles have been announced, but Sony has reportedly released a few titles in eastern Europe that use this. Some personal notes on the early version (CDS100?) of the Cactus Data Shield: I bought a copy of _My Private War_, by Phillip Boa & The Voodoo Club, from an online retailer. The disc is labeled "Kopiergeschützte CD - nicht am pc abspielbar" which translates literally to "copy-protected CD - not at the PC playable". Supposedly this is one of the BMG discs that was protected with Midbar's first product. The Plextor Plextools utility saw it as a single-session audio CD with 13 tracks, but when I asked it to play the disc it only saw the first 28 seconds of the first track, and stopped after playing just that much. My Panasonic CD "boom box" also thought the disc was only 28 seconds long, but it happily played past that point, and would let me select any track. The page at http://uk.eurorights.org/issues/cd/docs/natimb.shtml has an analysis of the CD _White Lilies Island_ by Natalie Imbruglia. http://www.cdrinfo.com/Sections/Articles/Specific.asp?ArticleHeadline=Cactus%20Data%20Shield%20200&index=0 has a very thorough examination of a CDS200 disc. Recommended reading. Subject: [2-4-6] ...on an audio CD (Key2Audio / Sony DADC) (2001/09/26) This was used to protect promotional copies of the Michael Jackson single "You Rock My World". See http://www.key2audio.com/ for product information. News articles: - http://news.cnet.com/news/0-1005-200-7284684.html The technology is designed to make the discs unrecognizeable to CD-ROM drives. According to the web pages, the product is licensed through Sony DADC. Subject: [2-4-7] ...on an audio CD (BayView Systems - Duolizer) (2001/09/26) The "Duolizer" system splits music into two pieces. The bulk of the music is on the CD, but a small but essential piece is streamed from a secure server over the Internet. The idea is to allow music publishers to distribute songs to the media and retail outlets ahead of scheduled releases. This was a response to songs appearing in MP3 form on the Internet before the CDs went into distribution. See http://www.bayviewsystems.com/solutions/duolizer.htm for product info. News articles: - http://news.cnet.com/news/0-1005-200-7132601.html This scheme can't be used for general CD protection, because if the music can be played on a computer at all, it can be captured with a program like Total Recorder (http://www.HighCriteria.com/). It will be reasonably effective for promotional copies of songs, though, where the goal is to prevent people from walking away with copies of the discs. As an added bonus, because the music is streamed from a central location, it could have a digital watermark added. If (say) somebody at a radio station made an MP3 copy, it might be possible to trace the source of the MP3 file back to the source. There is nothing on the product pages to suggest that such a scheme is currently in place. Subject: [2-4-8] ...on an audio CD (Sanyo) (2001/09/29) Sanyo has joined the growing list of companies to announce CD copy protection. It's not clear if this is their own scheme or one licensed from another company. News articles: - http://www.cnn.com/2001/TECH/ptech/09/24/sanyo.cd.rom.protection.idg/index.html Subject: [2-4-9] How does the Doc-Witness OpSecure CD-ROM work? (2002/08/22) The disc has an embedded secure micro (like a smart card) that is activated when the laser light strikes a photodetector. The light is converted to electrical impulses, the impulses drive the chip, and if all goes well the results are presented to the drive via an embedded light-emitting diode. Making an exact duplicate of the disc would be very difficult. It's unclear whether this technology actually makes it harder to get a working copy of the contents. The scheme seems to essentially be a combination of an "uncopyable" disc and a hardware dongle, both of which have been around for years (neither of which have brought an end to piracy). The company's web site is http://www.doc-witness.com/. News articles: - http://www.technologyreview.com/articles/prototype10902.asp?p=7 Subject: [2-4-10] What's the Sony BMG rootkit (First 4 Internet XCP)? (2005/11/29) A "rootkit" is a bit of software that changes the way your system works, usually for malicious purposes. Sony BMG included one with some audio CDs released in late 2005. The software in question is "XCP Content Management" from First 4 Internet Ltd (http://www.first4internet.com/). It uses a combined audio CD and CD-ROM format. When placed in a CD-ROM drive on a Windows system, it uses the autorun feature to install itself. XCP includes anti-piracy technology that acts to prevent you from copying it, and cloaking technology to prevent you from seeing it. If you manage to find it, and try to remove it, it disables your CD-ROM drive. (As with other technologies of this type, disabling autorun or holding down the shift key while loading a CD will prevent the copy protection from loading. Because this protection is difficult to remove you must be very careful when handling Sony music CDs on your computer.) This produced a tremendous backlash against Sony BMG. Besides the usual objections to this sort of thing -- installing software that prevents your system from functioning normally -- the rootkit could be used by other bits of adware/spyware to conceal themselves. (It was used by enterprising game cheats to circumvent World of Warcraft's elaborate anti-cheating system, and a couple of viruses were using it to conceal themselves.) After news of XCP became widely known, Sony BMG began offering a software download on its site that would identify affected systems by removing the cloaking, but wouldn't remove the rootkit entirely. You could get the patch by filling out a marketing survey that -- according to Sony's privacy policy -- could lead to having your e-mail address added to their mailing lists. Sony BMG eventually made an uninstaller available, but only if you made some educated guesses on their web site and jumped through some ridiculous hoops: http://www.sysinternals.com/blog/2005/11/sony-you-dont-reeeeaaaally-want-to_09.html It turned out the web-based uninstaller created security vulnerabilities, causing yet more problems. Some notes here: http://blogs.washingtonpost.com/securityfix/2005/11/sony_uninstall_.html There is some network activity associated with the rootkit. It appears to be connecting to a Sony web site to look for updated content. There is some speculation that this could be used for tracking purposes, though Sony denies that they are doing so. A class-action lawsuit was filed on behalf of residents of the state of California (USA) in November 2005, and similar actions were planned elsewhere. Use of the technology was suspended in November 2005 in response to public pressure. Later that month, after the various security problems became prominent, Sony BMG elected to recall all XCP-protected CDs. News articles: - http://sfgate.com/cgi-bin/article.cgi?file=/news/archive/2005/11/02/financial/f160614S41.DTL - http://sfgate.com/cgi-bin/article.cgi?file=/c/a/2005/11/11/MNGFMFMNV61.DTL&type=tech - http://www.eff.org/deeplinks/archives/004117.php - http://blogs.washingtonpost.com/securityfix/2005/11/the_bush_admini.html - http://today.reuters.co.uk/news/newsArticle.aspx?type=technologyNews&storyID=2005-11-11T183106Z_01_MOL166114_RTRIDST_0_TECH-SONY-COPYPROTECTION-DC.XML&archived=False Nice summary of the whole debacle: - http://www.businessweek.com/technology/content/nov2005/tc20051129_938966.htm List of affected CDs: - http://cp.sonybmg.com/xcp/english/titles.html - http://www.eff.org/deeplinks/archives/004144.php Technical info: - http://www.sysinternals.com/blog/2005/11/more-on-sony-dangerous-decloaking.html - http://www.f-secure.com/v-descs/xcp_drm.shtml Subject: [2-5] What's a multisession disc? (2005/02/07) A session is a recorded segment that may contain one or more tracks of any type. The CD recorder doesn't have to write the entire session at once -- you can write a single track, and come back later and write another -- but the session must be "closed" before a standard audio CD or CD-ROM player will be able to use it. Additional sessions can be added until the *disc* is closed or there's no space left. This provides a simple and fairly reliable way to write some data to a disc now and still be able to add more later. The trouble with using multiple sessions is that, every time you write a chunk of data, you incur a fairly substantial amount of overhead: 23MB after the first session, and 14MB for every subsequent session. This overhead lead to the development of "packet writing", which allows drag-and-drop recording, but works in an entirely different way (see section (6-3)). Multisession writing was first used on PhotoCD discs, to allow additional pictures to be appended to existing discs. Today it's most often used with "linked" multisession discs, and occasionally for CD-Extra discs. These require a bit more explanation. When you put a data CD into your CD-ROM drive, the OS finds the last closed session on the disc and reads the directory from it. (Well, that's how it's supposed to work. On some older operating systems and CD-ROM drives, you may get different results.) If the CD was written in ISO-9660 format -- most store-bought CD-ROMs are -- the directory entries can point at any file on the CD, no matter which session it was written in. Most of the popular CD creation programs allow you to "link" one or more earlier sessions to the session currently being burned. This allows the files from the previous sessions to appear in the last session without taking up any additional space on the CD (except for the directory entry). You can also "remove" or "replace" files, by putting a newer version into the last session, and by not including a link to the older version. In contrast, when you put an audio CD into a typical CD player, it only looks at the first session. For this reason, multisession writes don't work for audio CDs, but as it happens this limitation can be turned into an advantage. See section (3-14) for details. This limitation does *not* mean you have to write an entire audio CD all at once; see section (2-9) for an overview of track-at-once writing. (Some audio CD players do seem to be able to recognize all of the tracks on a multisession audio disc. Most do not. The only way to know for sure is to try and see. If you are planning to give an audio CD you create to others, it would be wise to write it in a single session.) Note that mixing MODE-1 (CD-ROM) and MODE-2 (CD-ROM/XA) sessions on a single disc isn't allowed. You could create such a thing, but many CD-ROM drives will have a hard time recognizing it. See also http://www.roxio.com/en/support/cdr/multisession.html, which goes into more depth. On a Macintosh, discs written in HFS or HFS+ format cannot link files back to earlier sessions. Adding a new session will cause the previous session to disappear. Quick recap: if you want to write some data to a CD-ROM now, and some more later, you write a single data track in multiple sessions (or with packet writing). If you want to write some audio tracks to a CD now, and some more later, you write multiple audio tracks in a single session. Subject: [2-6] What are subcode channels? (2002/12/10) There are eight subcode channels (P,Q,R,S,T,U,V,W). The exact method of encoding is discussed in section (2-43), but it's really only important to note the data is distributed uniformly across the entire CD, and each channel can hold a total of about 4MB. The P subcode channel identifies the start of a track, but is usually ignored in favor of the Q channel. The Q subcode channel includes useful information, which can be read and written on many recorders. The user data area contains three types of subcode-Q data: position information, media catalog number (MCN), and ISRC code. Other forms are found in the lead-in, and are used to enable multisession and describe the disc TOC (table of contents). The position information is used by audio CD players to display the current time, and has track/index information. This can be controlled when doing Disc-At-Once recording. The ISRC (International Standard Recording Code) is used by the recording industry. It states the country of origin, owner, year of issue, and serial number of tracks, and may be different for each track. It's optional; many CDs don't use this. The media catalog number is similar, but is constant per disc. Note these are different from the UPC codes. The R-W subcode channels are used for text and graphics in certain applications, such as CD+G (CD w/graphics, supported by SegaCD among others). A new use has been devised by Philips, called ITTS. It enables properly equipped players to display text and graphics on Red Book audio discs. The most recent result of this technology is "CD-Text", which provides a way to embed disc and track data on a standard audio CD. Subject: [2-7] Are the CD Identifier fields widely used? (2002/12/20) Not many publishers use them, and not all devices can read all of the fields. Programs that identify audio CDs automatically don't rely on an embedded serial number. Instead, they compute an ID based on the quantity and positions of the audio tracks, measured down to 1/75th of a second. http://www.gracenote.com/ has a collection of CD information. Subject: [2-8] How long does it take to burn a CD-R? (2001/05/31) It depends on how much data you're going to burn, and how fast your drive is. Burning 650MB of data takes about 74 minutes at 1x, 37 minutes at 2x, and 19 minutes at 4x, but you have to add a minute or two for "finalizing" the disc. Remember that single speed for CD-ROMs is 150KB/sec, double speed is 300KB/sec, and so on. If you have half the data, it will finish in (about) half the time. If you record the same thing twice as fast, it will finish in (about) half the time. Most CD recording speeds are linear, i.e. recording at 12x is twice as fast as recording at 6x. If the drive uses a PCAV mechanism (see section (5-22)) the speed varies depending on which part of the disc you're recording. If a "20x" drive uses PCAV to get 12x at the start of the disc and 20x near the outside, you know that burning 60 minutes of audio will take somewhere between about 5 minutes and about 3 minutes. Subject: [2-9] What's the difference between disc-at-once and track-at-once? (2002/06/24) There are two basic ways of writing to a CD-R. Disc-at-once (DAO) writes the entire CD in one pass, possibly writing multiple tracks. The entire burn must complete without interruption, and no further information may be added. Track-at-once (TAO) allows the writes to be done in multiple passes. There is a minimum track length of 300 blocks (600K for typical data CDs), and a maximum of 99 tracks per disc, as well as a slight additional overhead associated with stopping and restarting the laser. Because the laser is turned off and on for every track, the recorder leaves a couple of blocks between tracks, called run-out and run-in blocks. If done correctly, the blocks will be silent and usually unnoticeable. CDs with tracks that run together will have a barely noticeable "hiccup". Some combinations of software and hardware may leave junk in the gap, resulting in a slight but annoying click between tracks. Some drives and/or software packages may not let you control the size of the gap between audio tracks when recording in track-at-once mode, leaving you with 2-second gaps even if the original didn't have them. Many recorders, starting with the venerable Philips CDD2000, allow "session-at-once" (SAO) recording. This gives you disc-at-once control over the gaps between tracks, but allows you to leave the disc open. This can be handy when writing CD Extra discs (see section (3-14)). There are some cases where disc-at-once recording is required. For example, it may be difficult or impossible to make identical backup copies of some kinds of discs without using disc-at-once mode (e.g. copy-protected PC games). Also, some CD mastering plants may not accept discs recorded in track-at-once mode, because the gaps between tracks will show up as uncorrectable errors. The bottom line is that disc-at-once recording gives you more control over disc creation, especially for audio CDs, but isn't always appropriate or necessary. It's a good idea to get a recorder that supports both disc-at-once and track-at-once recording. Subject: [2-10] Differences between recording from an image and on-the-fly? (1998/12/20) Many CD-R creation packages will give you a choice between creating a complete image of the CD on disk and doing what's called "on-the-fly" writing. Each method has its advantages. Disc image files are sometimes called virtual CDs or VCDs (not to be confused with VideoCD). These are complete copies of the data as it will appear on the CD, and so require that you have enough hard drive space to hold the complete CD. This could be as much as 650MB for CD-ROM or 747MB for an audio disc when using 74-minute blanks. If you have both audio and data tracks on your CD, there would be an ISO-9660 filesystem image for the data track and one or more 16-bit 44.1KHz stereo sound images for the audio tracks. (On the Mac, you might instead use an HFS filesystem for the data track. You can create the image with Mac CD recording software, or create it as a DiskCopy image file and then burn the data fork under a different OS.) On-the-fly recording often uses a "virtual image", in which the complete set of files is examined and laid out, but only the file characteristics are stored, not the data. The contents of the files are read while the CD is being written. This method requires less available hard drive space and may save time, but increases the risk of buffer underruns (see (4-1)). With most software this also gives greater flexibility, since it's easier to add, remove, and shuffle files in a virtual image than a physical one. A CD created from an image file would be identical to one created with on-the-fly recording, assuming that both would put the same files in the same places. The choice of which to use depends on user preference and hardware capability. Subject: [2-11] How does an audio CD player know to skip data tracks? (1999/04/11) There are subcode flags in the Q channel for each track: Data If set, the track contains data; if not, the track contains audio. Digital Copy Permitted Used by SCMS. Set to allow copies, clear to prevent them. Four-Channel Audio The Red Book standard allows four-channel audio, though very few discs have ever been made that use it. Pre-Emphasis Set if the audio was recorded with pre-emphasis. The last two are rarely used. Subject: [2-12] How does CD-RW compare to CD-R? (2001/07/06) CD-RW is short for CD-Rewritable. It used to be called CD-Erasable (CD-E), but some marketing folks changed it so it wouldn't sound like your important data gets erased on a whim. The difference between CD-RW and CD-R is that CD-RW discs can be erased and rewritten, while CD-R discs are write-once. Other than that, they are used just like CD-R discs. Let me emphasize that: they are used just like CD-R discs. You can use packet writing on both CD-R and CD-RW, and you can use disc-at-once audio recording on both CD-R and CD-RW. Some software may handle CD-RW in a slightly different way, because you can do things like erase individual files, but the recorder technology is nearly identical. CD-RW drives use phase-change technology. Instead of creating "bubbles" and deformations in the recording dye layer, the state of material in the recording layer changes from crystalline to amorphous form. The different states have different refractive indices, and so can be optically distinguished. These discs are not writable by standard CD-R drives, nor readable by most older CD readers (the reflectivity of CD-RW is far below CD and CD-R, so an Automatic Gain Control circuit is needed to compensate). Most new CD-ROM drives do support CD-RW media, but not all them will read CD-RW discs at full speed. A few older audio CD players and many new ones can handle CD-RW discs, but many can't. If you want to create audio CDs on CD-RW media, make sure that your player can handle them. All CD-RW recorders can write to CD-R media, so the only reason not to buy a CD-RW recorder is price. Some Internet sites like to put the devices in completely separate categories, calling them "CD recorders" and "CD ReWriters", but the differences between them don't really merit such a distinction. Think of a "CD ReWriter" as a CD recorder that can also make use of CD-RW media. Oddly enough, it may be easier for a DVD drive to read CD-RW discs than CD-R discs, because of the way the media is constructed. CD-RW media is more expensive than CD-R, but recent price reductions have narrowed the gap considerably. There is a limit to the number of times an area of the disc can be rewritten, but that number is relatively high (the Orange Book requires 1000, but some manufacturers have claimed as much as 100,000). Of course, this is under laboratory conditions. If you don't handle the disc carefully, you will add scratches, dirt, fingerprints, and other obstacles that make the disc harder for the drive to read. It appears that CD-RW discs have speed ratings encoded on them, so discs that are only certified for 2x recording can't be written to at 4x (or, for that matter, 1x). To make things more complicated, different media is required for high-speed CD-RW drives (those that exceed 4x). If you're trying to decide if you want a drive that supports CD-RW, see section (5-16). Subject: [2-13] Can DVD players read CD-Rs? (2001/11/28) The only discs that a DVD player is guaranteed to read are DVD discs. Support for CD-ROM, CD-R, and CD-RW may be included, but is by no means guaranteed. CD-R was designed to be read by an infrared 780nm laser. DVD uses a visible red 635nm or 650nm laser, which aren't reflected sufficiently by the organic dye polymers used in CD-R media. As a result, many DVD players can't read CD-R media. Some DVD players come with two lasers so that they can read CD-R. For a technical discussion, see http://www2.osta.org/osta/html/cddvd/intro.html and http://www.emedialive.com/EM1998/bennett3.html (web archive: http://web.archive.org/web/20040224114428/http://www.emediapro.com/EM1998/bennett3.html). CD-RW discs have a different formulation, and may work even on players that can't handle CD-R media. If CD-R media doesn't work, try copying the disc to CD-RW instead (assuming your recorder supports CD-RW). Some DVD-ROM drives may be unable to read multisession discs. In general, though, DVD-ROM drives (as opposed to DVD players) are able to read CD-R media. If the box doesn't say that something is supported, assume that the feature isn't. Look for the MultiRead or MultiPlay logos, which indicate that the DVD player or DVD-ROM drive can read CD-R and CD-RW. See also "Is XXX compatible with DVD" in the DVD FAQ: http://www.dvddemystified.com/dvdfaq.html#2.4.3 http://www.dvddemystified.com/dvdfaq.html#2.4.4 Subject: [2-14] Should I buy a DVD recorder instead? (2007/07/08) Your best bet is to get a "combo" drive that records on CDs as well. With recent cost reductions to DVD hardware, there's no real reason to buy a drive that only handles CDs or only handles DVDs (and in fact they're increasingly difficult to find). CDs are quickly surpassing the venerable 3.5" floppy disk as the most universal physical media. DVD-ROM drives and DVD players weren't as successful initially as some in the industry had hoped -- near the end of 2000, one of the major computer sellers was offering an "upgrade" on their systems from DVD-ROM drives to CD recorders. These days it's hard to buy a computer that doesn't support all formats. DVD-R recorders and media were initially very expensive, but eventually came down to consumer levels. An example: electroweb.com was, as of early February '98, selling a Pioneer CDVR-S101 DVD-Recordable Drive for US$18000. In June '99, the same site had a Pioneer CDVR-S201 for US$5100. In October 2001 the Pioneer DVR-A03PK was on sale for $699, and the price of media had fallen from $50 to $15 per disc. As mentioned in section (0-2), this FAQ will not be expanding to cover DVD recorders. See http://www.dvddemystified.com/dvdfaq.html instead. Subject: [2-15] What are "jitter" and "jitter correction"? (1998/04/06) The first thing to know is that there are two kinds of jitter that relate to audio CDs. The usual meaning of "jitter" refers to a time-base error when digital samples are converted back to an analog signal; see the jitter article on http://www.digido.com/ for an explanation. The other form of "jitter" is used in the context of digital audio extraction from CDs. This kind of "jitter" causes extracted audio samples to be doubled-up or skipped entirely. (Some people will correctly point out that the latter usage is an abuse of the term "jitter", but we seem to be stuck with it.) "Jitter correction", in both senses of the word, is the process of compensating for jitter and restoring the audio to its intended form. This section is concerned with the (incorrect use of) "jitter" in the context of digital audio extraction. The problem occurs because the Philips CD specification doesn't require block-accurate addressing. While the audio data is being fed into a buffer (a FIFO whose high- and low-water marks control the spindle speed), the address information for audio blocks is pulled out of the subcode channel and fed into a different part of the controller. Because the data and address information are disconnected, the CD player is unable to identify the exact start of each block. The inaccuracy is small, but if the system doing the extraction has to stop, write data to disk, and then go back to where it left off, it won't be able to seek to the exact same position. As a result, the extraction process will restart a few samples early or late, resulting in doubled or omitted samples. These glitches often sound like tiny repeating clicks during playback. On a CD-ROM, the blocks have a 12-byte sync pattern in the header, as well as a copy of the block's address. It's possible to identify the start of a block and get the block's address by watching the data FIFO alone. This is why it's so much easier to pull single blocks off of a CD-ROM. With most CD-ROM drives that support digital audio extraction, you can get jitter-free audio by using a program that extracts the entire track all at once. The problem with this method is that if the hard drive being written to can't keep up, some of the samples will be dropped. (This is similar to a CD-R buffer underrun, but since the output buffer used during DAE is much smaller than a CD-R's input buffer, the problem is magnified.) Most newer drives (as well as nearly every model Plextor ever made) are based on an architecture that enables them to accurately detect the start of a block. An approach that has produced good results is to do jitter correction in software. This involves performing overlapping reads, and then sliding the data around to find overlaps at the edges. Most DAE programs will perform jitter correction. Subject: [2-16] Where can I learn more about the history of CD and CD-R? (2002/12/02) Some information about "the goode olde days" can be found in Robert Starrett's "The History of CD-R" article, currently available from http://www.roxio.com/en/support/cdr/historycdr.html. The first CD player was available in Japanese stores on October 1, 1982. CD-Recordable technology wasn't introduced until 1988. For a timeline, see http://www.oneoffcd.com/info/historycd.cfm. Back in the late 1980s, CD recorders cost thousands of dollars, and were part of systems the size of a washing machine. Disks cost US$100.00 each. Things started to get better in 1995, when Yamaha released the CDR100 (the first 4x recorder) for a mere US$5000.00. In September of 1995, HP released the 4020i (a 2x recorder based on the Philips CDD2000) for just under US$1000.00. Media was down to about US$8.00, though 80-minute discs were extremely rare and expensive (US$40.00 each, if you could find them at all). Subject: [2-17] Why don't audio CDs use error correction? (2007/08/08) Actually, they do. It is true that audio CDs use all 2352 bytes per block for sound samples, while CD-ROMs use only 2048 bytes per block, with most of the rest going to ECC (Error Correcting Code) data. The error correction that keeps your CDs sounding the way they're supposed to, even when scratched or dirty, is applied at a lower level. So while there isn't as much protection on an audio CD as there is on a CD-ROM, there's still enough to provide perfect or near-perfect sound quality under adverse conditions. All of the data written to a CD uses CIRC (Cross-Interleaved Reed-Solomon Code) encoding. Every CD has two layers of error correction, called C1 and C2. C1 corrects bit errors at the lowest level, C2 applies to bytes in a frame (24 bytes per frame, 98 frames per sector). In addition, the data is interleaved and spread over a large arc. (This is why you should always clean CDs from the center out, not in a circular motion. A circular scratch causes multiple errors within a frame, while a radial scratch distributes the errors across multiple frames.) If there are too many errors, the CD player will interpolate samples to get a reasonable value. This way you don't get nasty clicks and pops in your music, even if the CD is dirty and the errors are uncorrectable. Interpolating adjacent data bytes on a CD-ROM wouldn't work very well, so the data is returned without the interpolation. The second level of ECC and EDC (Error Detection Codes) works to make sure your CD-ROM stays readable with even more errors. It should be noted that not all CD players are created equal. There are different strategies for decoding CIRC, some better than others. Some CD-ROM drives can report the number of uncorrected C2 errors back to the application. This allows an audio extraction application to guarantee that the extracted audio matches the original. See http://web.archive.org/web/20031211151723/http://www.cdpage.com/dstuff/BobDana296.html for an overview of error correction from the perspective of media testing. If you really want to get into the gory technical details, there used to be a good page at http://www.ee.washington.edu/conselec/CE/kuhn/cdmulti/95x7/iec908.htm. Subject: [2-18] How does CD-R compare to MiniDisc? (2000/08/08) MiniDiscs, or MDs, are small (64mm) discs that hold about 140MB of data or 160MB of audio. By using sophisticated compression techniques they are able to compress audio by a 5:1 ratio, allowing a capacity of 74 minutes with little or no audible difference in quality. As with CD recorders, there are MD recorders that connect to your computer and MD recorders that connect to your stereo. There are stamped MDs that are similar to CDs in construction, and rewritable MDs that use magneto-optical technology. Audio MD recorders are generally more convenient than stand-alone audio CD recorders, because the playback mechanism allows a more flexible layout of audio data, so it's possible to delete a track from the middle of the MD and then write a longer one that is recorded in different places across the disc. The current generation of MD technology is unlikely to replace CD-R or DAT, however, because the lossy compression employed is disdained by audio purists. MD is more often positioned as a replacement for analog cassette tape, which it matches in portability and recordability, and surpasses in durability and its ability to perform random accesses. Computer-based MD recorders can write data, but may not be able to record audio. Check the specifications carefully. A wealth of information is available from http://www.minidisc.org/. If you want to transfer CD to MD or MD to CD-R, check there for more information. (It used to be item #37 in the FAQ, but doesn't seem to be now.) Subject: [2-19] What does finalizing (and closing and fixating) do? (2002/05/26) A disc that you can add data to is "open". All data is written into the current session. When you have finished writing, you close the session. If you want to make a multisession disc, you open a new session at the same time. If you don't open a new session then, you can't open one later, which means that it's impossible to add more data to the CD-R. The entire disc is considered "closed". The process of changing a session from "open" to "closed" is called "finalizing", "fixating", or just plain "closing" the session. When you close the last session, you have finalized, fixated, or closed the disc. A single-session disc has three basic regions: the lead-in, which has the Table of Contents (or TOC); the program area, with the data and/or audio tracks; and the lead-out, which is filled with zeroes and provides padding at the end of the disc. An "open" single-session disc doesn't yet have the lead-in or lead-out written. If you write data to a disc and leave the sess