| Patent application number | Description | Published |
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| 20080260027 | MODE UNIFORMITY SIGNALING FOR INTRA-CODING - Techniques for efficiently signaling one or more prediction modes for blocks in a macroblock. A mode uniformity indicator is provided for each macroblock to indicate whether all blocks in the macroblock are to be predicted using the same prediction mode. In an embodiment, an encoder signals a mode uniformity indicator and a prediction mode. In another embodiment, a decoder receives a mode uniformity indicator and a prediction mode, and predicts at least two blocks of the macroblock using the prediction mode if the mode uniformity indicator is true. | 10-23-2008 |
| 20080260030 | DIRECTIONAL TRANSFORMS FOR INTRA-CODING - Techniques for transforming the prediction error of intra-coded blocks using mode-dependent transform functions. In an embodiment, an encoder selects a set of transform functions to represent prediction error based on the spatial mode used for prediction. In an alternative embodiment, a decoder reconstructs an image block by using the signaled spatial mode to derive the corresponding set of transform functions. No additional signaling between encoder and decoder is required as compared to prior art implementations. | 10-23-2008 |
| 20080260031 | PIXEL-BY-PIXEL WEIGHTING FOR INTRA-FRAME CODING - Techniques for improving the accuracy of prediction in intra-frame coding. A prediction mode can specify a pixel along a direction independently of other pixels along the same direction. In an embodiment, an encoder selects a prediction mode to best represent the image block. In an alternative embodiment, a decoder reconstructs each pixel in the image block by weighting neighboring pixels according to a weight matrix specified by the prediction mode. | 10-23-2008 |
| 20080310504 | ADAPTIVE COEFFICIENT SCANNING FOR VIDEO CODING - This disclosure describes techniques for scanning coefficients of video blocks. In particular, the techniques of this disclosure adapt a scan order used to scan a two-dimensional block of coefficients into a one-dimensional coefficient vector based on statistics associated with one or more previously coded blocks. For example, statistics that indicate the likelihood that a given coefficient value in each position of a two-dimensional block is zero or non-zero may be collected for one or more previously coded blocks. At some point, an adjustment to the scan order can be made in order to better ensure that non-zero coefficients are grouped together near the front of the one-dimensional coefficient vector, which can improve the effectiveness of entropy coding. The collection of statistics and adjustment of scan order may be made separately for each possible prediction mode. | 12-18-2008 |
| 20080310507 | ADAPTIVE CODING OF VIDEO BLOCK PREDICTION MODE - This disclosure describes techniques for coding of header information of video blocks. In particular, the techniques of this disclosure select one of a plurality of prediction modes for use in generating a prediction block of a video block of a coding unit, the plurality of prediction modes including unidirectional prediction modes and multi-directional prediction modes that combine at least two unidirectional prediction modes. An encoding device encodes the prediction mode of the current video block based on prediction modes of one or more previously encoded video blocks of the coding unit. Likewise, a decoding unit receives encoded video data of a video block of a coding unit and decodes the encoded video data to identify one of a plurality of prediction modes for use in generating a prediction block of the video block based on prediction modes of one or more previously decoded video blocks of the coding unit. | 12-18-2008 |
| 20080310512 | SEPARABLE DIRECTIONAL TRANSFORMS - This disclosure describes techniques for transforming residual blocks of video data. In particular, a plurality of different transforms selectively applied to the residual blocks based on the prediction mode of the video blocks. At least a portion of the plurality of transforms are separable directional transform specifically trained for a corresponding prediction mode to provide better energy compaction for the residual blocks of the given prediction mode. Using separable directional transforms offers the benefits of lower computation complexity and storage requirement than use of non-separable directional transforms. Additionally, a scan order used to scan the coefficients of the residual block may be adjusted when applying separable directional transforms. In particular, the scan order may be adjusted based on statistics associated with one or more previously coded blocks to better ensure that non-zero coefficients are grouped near the front of the one-dimensional coefficient vector to improve the effectiveness of entropy coding. | 12-18-2008 |
| 20080310745 | ADAPTIVE COEFFICIENT SCANNING IN VIDEO CODING - This disclosure describes techniques for scanning coefficients of video blocks, e.g., quantized and transformed coefficients. Rather than use conventional zig-zag scanning, the techniques of this disclosure adapt the scanning order based on statistics associated with previously coded blocks that were coded in the same prediction mode. For each prediction mode, statistics of the coefficients are stored, e.g., indicating probabilities that given coefficients are zero or non-zero. Periodically, adjustments to the scanning order can be made in order to better ensure that non-zero coefficients are grouped together and zero value coefficients are grouped together, which can improve the effectiveness of entropy coding. The techniques of this disclosure provide thresholds and threshold adjustments that can reduce the frequency that the scanning order adjustments occur, yet still achieve desired improvements in compression due to such scanning order adjustments. | 12-18-2008 |
| 20090003440 | SUB-BAND SCANNING TECHNIQUES FOR ENTROPY CODING OF SUB-BANDS - This disclosure describes techniques useful in the encoding and/or decoding of video data of a video sequence. In general, this disclosure sets forth scanning techniques useful in the context of sub-band coding, which may improve the level of compression that can be achieved by entropy coding following sub-band coding. In one example, a method of encoding video data of a video sequence comprises sub-band encoding the video data to generate a plurality of sub-bands, scanning each of the sub-bands from two-dimensional blocks into one-dimensional vectors based on scan orders defined for each of the sub-bands, and entropy encoding each of the scanned sub-bands. | 01-01-2009 |
| 20090097548 | ENHANCEMENT LAYER CODING FOR SCALABLE VIDEO CODING - This disclosure describes scalable video coding techniques. In particular, the techniques may be used to encode refinements of a video block for enhancement layer bit streams in a single coding pass, thereby reducing coding complexity, coding delay and memory requirements. In some instances, the techniques encode each nonzero coefficient of a coefficient vector of the enhancement layer without knowledge of any subsequent coefficients. Coding the enhancement layer in a single pass may eliminate the need to perform a first pass to analyze the coefficient vector and a second pass for coding the coefficient vector based on the analysis. | 04-16-2009 |
| 20090097558 | SCALABLE VIDEO CODING TECHNIQUES FOR SCALABLE BITDEPTHS - This disclosure describes video coding techniques that are executed in a bitdepth-based scalable video coding (SVC) scheme. Base layer video data and enhancement layer video data may be defined at different bitdepths. The techniques of this disclosure concern the coding of enhancement layer video blocks using a unique combination of inter-layer predictive coding modes after determining that inter-layer prediction should be used. In particular, two or more different inter-layer predictive coding modes may be utilized block corresponding to inter base layer blocks, and one of these inter-layer predictive coding modes may also be utilized for blocks corresponding to intra base layer blocks. Syntax information can be generated at the encoder and communicated with the bitstream, so that a decoder can use the proper inter-layer predictive coding mode in the decoding. | 04-16-2009 |
| 20090097568 | ENTROPY CODING OF INTERLEAVED SUB-BLOCKS OF A VIDEO BLOCK - This disclosure describes techniques for entropy coding of video blocks, and proposes a syntax element that may promote coding efficiency. The syntax element may identify a number of non-zero value sub-blocks within a video block, wherein the non-zero value sub-blocks comprise sub-blocks within the video block that include at least one non-zero coefficient. A method of coding a video block may comprise coding the syntax element, generating the non-zero value sub-blocks of the video block, and entropy coding the non-zero value sub-blocks. | 04-16-2009 |
| 20090175331 | TWO PASS QUANTIZATION FOR CABAC CODERS - This disclosure describes techniques for quantizing coefficients of a video block for a video coding process that supports context-based adaptive binary arithmetic coding (CABAC). A method may comprise estimating a last non-zero coefficient of the video block, and generating a set of quantized coefficients for the video block based on an assumption that the estimated last non-zero coefficient is actually the last non-zero coefficient of the video block. | 07-09-2009 |
| 20090175332 | QUANTIZATION BASED ON RATE-DISTORTION MODELING FOR CABAC CODERS - This disclosure describes techniques for quantizing coefficients of a video block for a video coding process that supports context-based adaptive binary arithmetic coding (CABAC). A method may comprise generating a plurality of sets of quantized coefficients for the video block, wherein each of the sets of quantized coefficients is defined based on an assumption that a particular one of the coefficients of the video block corresponds to a last non-zero coefficient of the video block, estimating a plurality of costs associated with coding the video block via the CABAC, wherein the estimated costs are based respectively on different ones of the sets of quantized coefficients, and selecting a given one of the sets of quantized coefficients associated with a lowest cost. | 07-09-2009 |
| 20090175334 | ADAPTIVE CODING OF VIDEO BLOCK HEADER INFORMATION - This disclosure describes techniques for adaptively coding video block header information based on previously encoded video blocks. A video encoder may adaptively select a coding table for use in encoding a syntax element of a current video block based on corresponding syntax elements of one or more previously encoded blocks. In one aspect, the video encoder may adaptively select the coding table for use in encoding a block type of the current block based on block types of one or more video blocks adjacent to the current video block, i.e., neighboring video blocks. The video encoder may also predict one or more other header syntax elements of the current block based on at least one of the previously encoded video blocks. If prediction is successful, the video encoder may encode a flag to indicate the success of prediction. | 07-09-2009 |
| 20090175336 | VIDEO CODING OF FILTER COEFFICIENTS BASED ON HORIZONTAL AND VERTICAL SYMMETRY - This disclosure recognizes and exploits the fact that some of the filter coefficients defined at the encoder may possess symmetry relative to other filter coefficients. Accordingly, this disclosure describes techniques in which a first set of the filter coefficients are used to predictively encode a second set of the filter coefficients, thereby exploiting any symmetry between filter coefficients. Rather than communicate all of the filter coefficients to the decoding device, the encoding device may communicate the first set of filter coefficients and difference values associated with the second set of filter coefficients. Using this information, the decoder may be able to reconstruct all of the filter coefficients. In some cases, if exact symmetry is imposed, the need to send the difference values may be eliminated and the decoder may be able to derive the second set of filter coefficients from the first set of filter coefficients. | 07-09-2009 |
| 20090175349 | LAYERED ENCODED BITSTREAM STRUCTURE - This disclosure describes techniques for generating a layered encoded bitstream structure that exploits correlation in header information among video blocks of a coded unit of video data. A video encoder configured to operate in accordance with the techniques of this disclosure separates header information of the video blocks of a slice (or other coded unit) from the residual information of the video blocks of the slice. The video encoder run-length encodes the header information of the video blocks to better exploit the correlation of the header information among the blocks of the slice. After encoding the header information of the blocks of the slice, the video encoder encodes the residual information for each of the blocks of the slice. The video encoder transmits the encoded header information as a first sequence of bits and transmits the encoded residual information as second sequence of bits. | 07-09-2009 |
| 20090213930 | FAST MACROBLOCK DELTA QP DECISION - A system and method for encoding multimedia video is described. As video is encoded a quantization parameter is selected for each macroblock. As described herein, the quantization parameter for each macroblock may be selected by limiting the universe of all possible quantization parameters to a particular range of possible quantization parameter values. This increases the speed of video encoding by reducing the number of quantization parameters that are tested for each video macroblock. | 08-27-2009 |
| 20090257489 | RATE-DISTORTION QUANTIZATION FOR CONTEXT-ADAPTIVE VARIABLE LENGTH CODING (CAVLC) - In general, this disclosure provides techniques for quantization of the coefficients of video blocks in a manner that can achieve a desirable balance of rate and distortion. The described techniques may analyze a plurality of quantization levels associated with each individual coefficient to select the quantization level for the individual coefficients that results in a lowest coding cost. Since CAVLC does not encode each coefficient independently, the techniques may compute the coding costs for each of the candidate quantization levels associated with the individual coefficients based on quantization levels selected for previously quantized coefficients and estimated (or predicted) quantization levels for subsequent coefficients of a coefficient vector. The quantization levels for each of the coefficients are selected based on computed coding costs to obtain a set of quantized coefficients that minimize a rate-distortion model. | 10-15-2009 |
| 20090257494 | SYMMETRY FOR INTEROPLATION FILTERING OF SUB-PIXEL POSITIONS IN VIDEO CODING - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
| 20090257499 | ADVANCED INTERPOLATION TECHNIQUES FOR MOTION COMPENSATION IN VIDEO CODING - This disclosure describes various interpolation techniques performed by an encoder and a decoder during the motion compensation process of video coding. In one example, an encoder interpolates pixel values of reference video data based on a plurality of different pre-defined interpolation filters. In this example, the decoder receives a syntax element that identifies an interpolation filter, and interpolates pixel values of reference video data based on the interpolation filter identified by the syntax element. In another example, a method of interpolating predictive video data includes generating half-pixel values based on integer pixel values, rounding the half-pixel values to generate half-pixel interpolated values, storing the half-pixel values as non-rounded versions of the half-pixel values, and generating quarter-pixel values based on the non-rounded versions of the half-pixel values and the integer pixel values. | 10-15-2009 |
| 20090257500 | OFFSETS AT SUB-PIXEL RESOLUTION - This disclosure describes techniques applied during video encoding and decoding processes. In one example, a method of encoding video data comprises calculating a plurality of offset values for a coded unit of the video data, wherein the offset values are associated with a plurality of different integer and sub-integer pixel locations, applying the offset values to predictive video blocks to generate offset predictive video blocks, and encoding video blocks of the coded unit based on the offset predictive video blocks. In another example, a method of decoding video data comprises receiving a plurality of offset values for a coded unit of the video data, wherein the offset values are associated with a plurality of different integer and sub-integer pixel locations, applying the offset values to predictive video blocks to generate offset predictive video blocks, and decoding video blocks of the coded unit based on the offset predictive video blocks. | 10-15-2009 |
| 20090257501 | INTERPOLATION-LIKE FILTERING OF INTEGER-PIXEL POSITIONS IN VIDEO CODING - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
| 20090257502 | RATE-DISTORTION DEFINED INTERPOLATION FOR VIDEO CODING BASED ON FIXED FILTER OR ADAPTIVE FILTER - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
| 20090257503 | ADVANCED INTERPOLATION TECHNIQUES FOR MOTION COMPENSATION IN VIDEO CODING - This disclosure describes various interpolation techniques performed by an encoder and a decoder during the motion compensation process of video coding. In one example, an encoder interpolates pixel values of reference video data based on a plurality of different pre-defined interpolation filters. In this example, the decoder receives a syntax element that identifies an interpolation filter, and interpolates pixel values of reference video data based on the interpolation filter identified by the syntax element. In another example, a method of interpolating predictive video data includes generating half-pixel values based on integer pixel values, rounding the half-pixel values to generate half-pixel interpolated values, storing the half-pixel values as non-rounded versions of the half-pixel values, and generating quarter-pixel values based on the non-rounded versions of the half-pixel values and the integer pixel values. | 10-15-2009 |
| 20090257668 | PREDICTION TECHNIQUES FOR INTERPOLATION IN VIDEO CODING - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
| 20100002770 | VIDEO ENCODING BY FILTER SELECTION - A method and a device are described for selecting between multiple available filters in an encoder to provide a frame having a low error and distortion rate. For each full and sub pixel position, determining whether to use an alternative filter over the default filter during interpolation by estimating the rate distortion gain of using each filter and signaling to the decoder the optimal filter(s) applied to each full and sub-pixel position. In one embodiment, identifying a reference frame and a current frame, interpolating the reference frame using a default filter to create a default interpolated frame, interpolating the reference frame using an alternative filter to create an alternative interpolated frame, determining for each sub-pixel position whether to use the default filter or the alternative filter based on a minimal cost to generate a final reference frame. | 01-07-2010 |
| 20100008430 | FILTERING VIDEO DATA USING A PLURALITY OF FILTERS - Systems and methods of filtering video data using a plurality of filters are disclosed. In an embodiment, a method includes receiving and decoding a plurality of filters embedded in a video data bitstream at a video decoder. The method includes selecting, based on information included in the video data bitstream, a particular filter of the plurality of filters. The method further includes applying the particular filter to at least a portion of decoded video data of the video data bitstream to produce filtered decoded video data. | 01-14-2010 |
| 20100074332 | OFFSET CALCULATION IN SWITCHED INTERPOLATION FILTERS - This disclosure describes techniques for adding offset to predictive video blocks during video coding. In one example, a method of encoding a video block includes interpolating a first block of predictive values based on a first reference video unit within a first list of reference data, and a second block of predictive values based on a second reference video unit within a second list of reference data, calculating, for sub-integer pixel positions, a first offset value based on the first block and the current video block, and a second offset value based on the first offset value and the second block, determining a final block of offset values based on the first block of predictive values, the second block of predictive values, the first offset values, and the second offset values, and encoding the current video block based on the final block of offset values. | 03-25-2010 |
| 20100086025 | QUANTIZATION PARAMETER SELECTIONS FOR ENCODING OF CHROMA AND LUMA VIDEO BLOCKS - This disclosure describes rules that may be applied during block-based video coding to ensure that quantization parameter selections for luma blocks will not adversely affect the quality of chroma blocks. In accordance with this disclosure, rate-controlled video encoding occurs in which quantization parameter changes in luma blocks are pre-evaluated to determine whether such quantization parameter changes in luma blocks will also cause quantization changes for chroma blocks. If quantization parameter changes in the luma blocks will also cause quantization changes for chroma blocks, then that quantization parameter change for luma blocks may be skipped and not evaluated. In this way, secondary effects of quantization parameter changes in the luma blocks (with respect to the chroma blocks) can be avoided. | 04-08-2010 |
| 20100086027 | EFFICIENT PREDICTION MODE SELECTION - In generally, techniques are described for efficiently selecting a prediction mode by which to predict predictive video data from reference video data. In particular, an apparatus may include a memory that stores at least a first and second reference coded unit that each includes a first and second reference video data unit, respectively. The apparatus may further comprise a motion compensation unit that performs default weighted prediction to predict a first version of a predictive video data unit from the first and second reference video data units and calculates an offset value for the first version of the predictive video data unit. The motion compensation unit may then perform, based on the calculated offset value, either implicit weighted prediction or explicit weighted prediction to predict a second version of the predictive video data unit and encode the predictive video data unit as either the first or second version. | 04-08-2010 |
| 20100086029 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels, for example, 64×64 pixels. In one example, an apparatus includes a video encoder configured to encode a video block having a size of more than 16×16 pixels, generate block-type syntax information that indicates the size of the block, and generate a coded block pattern value for the encoded block, wherein the coded block pattern value indicates whether the encoded block includes at least one non-zero coefficient. The encoder may set the coded block pattern value to zero when the encoded block does not include at least one non-zero coefficient or set the coded block pattern value to one when the encoded block includes a non-zero coefficient. | 04-08-2010 |
| 20100086030 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels, for example, 64×64 pixels. Each macroblock may be partitioned into two or more partitions, and two or more of the partitions may be encoded using different modes. In one example, an apparatus includes a video encoder configured to receive a video block having a size of more than 16×16 pixels, partition the block into partitions, encode one of the partitions using a first encoding mode, encode another of the partitions using a second encoding mode different from the first encoding mode, and generate block-type syntax information that indicates the size of the block and identifies the partitions and the encoding modes used to encode the partitions. | 04-08-2010 |
| 20100086031 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels, for example, 64×64 pixels. In one example, an apparatus includes a video encoder configured to receive a video coding unit, determine a first rate-distortion metric for encoding the video coding unit using first video blocks with sizes of 16×16 pixels, determine a second rate-distortion metric for encoding the video coding unit using second video blocks with sizes of more than 16×16 pixels, encode the video coding unit using the first video blocks when the first rate-distortion metric is less than second rate-distortion metric, and encode the video coding unit using the second video blocks when the second rate-distortion metric is less than the first rate-distortion metric. | 04-08-2010 |
| 20100086032 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels. In one example, an apparatus includes a video encoder configured to encode a coded unit comprising a plurality of video blocks, wherein at least one of the plurality of video blocks comprises a size of more than 16×16 pixels and to generate syntax information for the coded unit that includes a maximum size value, wherein the maximum size value indicates a size of a largest one of the plurality of video blocks in the coded unit. The syntax information may also include a minimum size value. In this manner, the encoder may indicate to a decoder the proper syntax decoder to apply to the coded unit. | 04-08-2010 |
| 20100086049 | VIDEO CODING USING TRANSFORMS BIGGER THAN 4X4 AND 8X8 - In a video processing system, a method and system for applying transforms larger than 8×8 and non-rectangular transforms, and generating transform size syntax elements indicative of the transforms for video decoding are provided. The transform size syntax element may be generated by an encoder based on a prediction block size of a video block and the contents of the video block. Further, the transform size syntax element may be generated according to a set of rules to select from 4×4, 8×8, and larger transform sizes during an encoding process. A decoder may perform an inverse transform based on the transform size syntax element and the rules used by the encoder. The transform size syntax element may be transmitted to the decoder as part of the encoded video bitstream. | 04-08-2010 |
| 20100098156 | WEIGHTED PREDICTION BASED ON VECTORIZED ENTROPY CODING - This disclosure describes methods that control the selection of predictive coding techniques for enhancement layer video blocks based on characteristics of vectorized entropy coding for such enhancement layer video blocks. In accordance with this disclosure, the predictive techniques used for predictive-based video coding of enhancement layer video blocks are dependent upon the vectorized entropy coding used for such enhancement layer the video blocks. For each coded unit, predictive coding techniques (e.g. weighted or non-weighted prediction) may be selected depending upon whether the vectorized entropy coding defines a single vector for the video blocks of that coded unit or multiple vectors for the video blocks of that coded unit. | 04-22-2010 |
| 20100111182 | DIGITAL VIDEO CODING WITH INTERPOLATION FILTERS AND OFFSETS - This disclosure describes techniques for encoding digital video data using interpolation filters and offsets. An encoder may be configured to select interpolation filters for sub-pixel precision motion estimation based on historical interpolation results obtained for previously encoded video units, such as frames or slices. The encoder also may be configured to compute and assign offsets to the sub-pixel positions after interpolation based on differences between a reference unit and the unit to be coded. The computation and assignment of offsets may be performed before motion estimation. Motion estimation may be refined so that the motion search considers sub-pixel positions to which offsets have been previously added and evaluates sub-pixel positions that have a non-zero offset. In some cases, interpolation filter selection, offset computation, and/or refined motion estimation for a given unit may be performed in a single encoding pass. | 05-06-2010 |
| 20100158103 | COMBINED SCHEME FOR INTERPOLATION FILTERING, IN-LOOP FILTERING AND POST-LOOP FILTERING IN VIDEO CODING - In one example, this disclosure describes filtering techniques for filtering of video blocks of a video unit. The filtering techniques may select one or more different types of filtering for each video block of the video unit based on various factors such as whether the video block is inter-coded or intra-coded, and whether adaptive interpolations were preformed during a motion compensation process during the encoding of the video block. When adaptive interpolations were performed, the adaptive interpolations may provide a level of filtering that renders additional filtering unnecessary or undesirable in some cases. | 06-24-2010 |
| 20100260262 | EFFICIENT TRANSCODING OF B-FRAMES TO P-FRAMES - This disclosure describes techniques for efficient transcoding from a first format that supports I-units, P-units and B-units to a second format that supports I-units and P-units but does not support the B-units. In particular, this disclosure provides techniques for converting B-frames or B-slices of the first format into P-frames or P-slices of the second format. The techniques avoid the need to decode and re-encode that frames or slices. Instead, residuals associated with the B-video blocks in the first format are augmented and made to be dependent upon only one of the two lists associated with the B-video blocks so that such B-video blocks in the first format can be redefined as P-video blocks in the second format. | 10-14-2010 |
| 20100296579 | ADAPTIVE PICTURE TYPE DECISION FOR VIDEO CODING - A video encoding apparatus determines whether to encode a key frame of a group of pictures using a bi-directional prediction mode. In one example, a video encoding apparatus includes a mode select unit configured to generate a virtual key frame for a current group of pictures based on a previous key frame of a previous group of pictures and a next key frame of a next group of pictures, calculate an error value representing error between a current key frame of the current group of pictures and the virtual key frame, and determine whether the error value exceeds a threshold value, and a video encoder configured to encode the current key frame using a bi-directional prediction encoding mode when the error value does not exceed the threshold value. The video encoder may comprise the mode select unit, or a preprocessing unit of the apparatus may comprise the mode select unit. | 11-25-2010 |
| 20100309286 | ENCODING OF THREE-DIMENSIONAL CONVERSION INFORMATION WITH TWO-DIMENSIONAL VIDEO SEQUENCE - This disclosure describes techniques for encoding a two-dimensional (2D) video sequence of video frames along with three-dimensional (3D) conversion information comprising a set of parameters that can be applied to each of the video frames of the 2D sequence to generate 3D video data. The set of parameters may comprise a relatively small amount of data that can be applied to each of the original video frames of the 2D sequence to generate secondary views of each of the original video frames. The original video frames and the secondary views may collectively define a stereoscopic 3D video sequence. The 2D sequence and the set of parameters may comprise significantly less data than would otherwise be needed to communicate a 3D sequence. This disclosure also describes some exemplary syntax that may be used to encode the set of parameters in an effective and efficient manner. | 12-09-2010 |
| 20100316134 | ASSEMBLING MULTIVIEW VIDEO CODING SUB-BISTREAMS IN MPEG-2 SYSTEMS - A demultiplexer may assemble view components of sub-bitstreams. In one example, an apparatus comprises a demultiplexer that produces a multiview video coding (MVC) standard compliant bitstream from a received bitstream comprising a primary sub-bitstream and an embedded sub-bitstream. To produce the MVC standard compliant bitstream, the demultiplexer determines whether a view component of the primary sub-bitstream has a view order index that is greater than a view order index of a view component of the embedded sub-bitstream, and to add the view component from the sub-bitstream for which the view order index is lower to the produced bitstream. The received bitstream may comprise delimiter network abstraction layer (NAL) units between each view component to differentiate the view components. The apparatus may further comprise a video decoder to decode the bitstream produced by the demultiplexer. | 12-16-2010 |
| 20100329329 | 8-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing an 8-point inverse discrete cosine transform (IDCT). An apparatus comprising an 8-point inverse discrete cosine transform (IDCT) hardware unit may implement these techniques to transform media data from a frequency domain to a spatial domain. The 8-point IDCT hardware unit includes an even portion comprising factors A, B that are related to a first scaled factor (μ) in accordance with a first relationship. The 8-point IDCT hardware unit also includes an odd portion comprising third, fourth, fifth and sixth internal factors (G, D, E, Z) that are related to a second scaled factor (η) in accordance with a second relationship. The first relationship relates the first scaled factor to the first and second internal factors. The second relationship relates the second scaled factor to the third, fourth, fifth and sixth internal factors. | 12-30-2010 |
| 20100329338 | LOW COMPLEXITY B TO P-SLICE TRANSCODER - A system and method for transcoding compressed multimedia video is described. Particularly, a system and method for converting Bi-Predictive frame to transcoded Predictive frames, is disclosed. Present embodiments accomplish this conversion with minimal additional error, thereby providing an efficient means for maintaining video quality even after transcoding. | 12-30-2010 |
| 20100329342 | VIDEO CODING BASED ON FIRST ORDER PREDICTION AND PRE-DEFINED SECOND ORDER PREDICTION MODE - This disclosure describes video encoding and decoding techniques in which a first order prediction process and a second order prediction process are used in combination to generate predictive video blocks for video coding. First order prediction may be similar to conventional motion estimation and motion compensation that generates residual video blocks. The second order prediction may involve a process similar to conventional intra-prediction, but is performed on the residual video blocks. The techniques of this disclosure may pre-define the second order prediction to a specific mode, such as a mode similar to the intra-DC mode used in intra coding. In addition, the techniques of this disclosure may combine aspects of the first order and second order prediction into a single process so that the effects of second order prediction on the residuals are taken into account during the first order prediction process, which may improve compression. | 12-30-2010 |
| 20110002388 | TEMPLATE MATCHING FOR VIDEO CODING - In one aspect of this disclosure, template matching motion prediction is applied to B-frames. In another aspect of this disclosure, template matching motion prediction as applied to video block coding may include generating a template offset, generating a weighted sum of absolute differences, selecting a number of hypotheses used to encode video blocks based on the cost associated with the number of hypotheses and signaling, with a new syntax, to a decoder, the number of hypotheses used in encoding, rejecting hypotheses if the difference in value between a hypothesis and a reference hypothesis is greater than a threshold value, and/or generating the content of a sub-block that does not have reconstructed data available by combining motion-compensated prediction and luma residuals. | 01-06-2011 |
| 20110007799 | NON-ZERO ROUNDING AND PREDICTION MODE SELECTION TECHNIQUES IN VIDEO ENCODING - In one aspect of this disclosure, techniques are described for selecting among default weighted prediction, implicit weighted prediction, and explicit weighted prediction. In this context, techniques are also described for adding offset to prediction data, e.g., using the format of explicit weighted prediction to allow for offsets to predictive data that is otherwise determined by implicit or default weighted prediction. | 01-13-2011 |
| 20110007802 | NON-ZERO ROUNDING AND PREDICTION MODE SELECTION TECHNIQUES IN VIDEO ENCODING - In one aspect of this disclosure, rounding adjustments to bi-directional predictive data may be purposely eliminated to provide predictive data that lacks any rounding bias. In this case, rounded and unrounded predictive data may both be considered in a rate-distortion analysis to identify the best data for prediction of a given video block. In another aspect of this disclosure, techniques are described for selecting among default weighted prediction, implicit weighted prediction, and explicit weighted prediction. In this context, techniques are also described for adding offset to prediction data, e.g., using the format of explicit weighted prediction to allow for offsets to predictive data that is otherwise determined by implicit or default weighted prediction. | 01-13-2011 |
| 20110007803 | DIFFERENT WEIGHTS FOR UNI-DIRECTIONAL PREDICTION AND BI-DIRECTIONAL PREDICTION IN VIDEO CODING - In one aspect of this disclosure, techniques are described for the decoupling of uni-directional and bi-directional prediction weights, particularly for explicit weighted predictions of video blocks within a B-unit. According to this disclosure, explicit weights communicated in the bitstream may be applied by a decoder for explicit bi-directional prediction, but different weights (which may be default weights or separately defined explicit unidirectional weights) may be used for explicit uni-directional prediction. The described techniques may improve video quality relative to techniques that use the same explicit weights for explicit bi-directional prediction and explicit uni-directional prediction within a B-unit. | 01-13-2011 |
| 20110032999 | SIGNALING CHARACTERISTICS OF AN MVC OPERATION POINT - Source and destination video devices may use data structures that signal details of an operation point for an MPEG-2 (Motion Picture Experts Group) System bitstream. In one example, an apparatus includes a multiplexer that constructs a data structure corresponding to a multiview video coding (MVC) operation point of an MPEG-2 (Motion Picture Experts Group) System standard bitstream, wherein the data structure signals a rendering capability value that describes a rendering capability to be satisfied by a receiving device to use the MVC operation point, a decoding capability value that describes a decoding capability to be satisfied by the receiving device to use the MVC operation point, and a bitrate value that describes a bitrate of the MVC operation point, and that includes the data structure as part of the bitstream, and an output interface that outputs the bitstream comprising the data structure. | 02-10-2011 |
| 20110064146 | MEDIA EXTRACTOR TRACKS FOR FILE FORMAT TRACK SELECTION - A video coding apparatus may be configured to utilize media extractors in a media extractor track that reference two or more non-consecutive network access layer (NAL) units of a separate track. An example apparatus includes a multiplexer to construct a first track including a video sample comprising NAL units, based on encoded video data, wherein the video sample is included in an access unit, construct a second track including an extractor that identifies at least first one of the NAL units in the video sample of the first track, and wherein the extractor identifies a second NAL unit of the access unit, wherein the first identified NAL unit and the second identified NAL unit are non-consecutive, and include the first track and the second track in a video file conforming at least in part to ISO base media file format. The identified NAL units may be in separate tracks. | 03-17-2011 |
| 20110096832 | DEPTH MAP GENERATION TECHNIQUES FOR CONVERSION OF 2D VIDEO DATA TO 3D VIDEO DATA - This disclosure describes techniques for generating depth maps for video units, such as video frames or slices video frames. The techniques may be performed by a video encoder in order to convert two-dimensional (2D) video to three-dimensional (3D) video. The techniques may alternatively be performed by a video decoder in order to convert received 2D video to 3D video. The techniques may use a combination of motion and color considerations in the depth map generation process. | 04-28-2011 |
| 20110099594 | STREAMING ENCODED VIDEO DATA - A source device may signal characteristics of a media presentation description (MPD) file such that a destination device may select one of a number of presentations corresponding to the MPD file and retrieve one or more video files of the selected presentation. In one example, an apparatus for transporting encoded video data includes a management unit configured to receive encoded video data comprising a number of video segments and forms a presentation comprising a number of video files, each of the video files corresponding to a respective one of the video segments, and a network interface configured to, in response to a request specifying a temporal section of the video data, output at least one of the video files corresponding to the number of video segments of the requested temporal section. A client may request temporally sequential fragments from different ones of the presentations. | 04-28-2011 |
| 20110150078 | 8-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing an 8-point discrete cosine transform (DCT). An apparatus comprising an 8-point discrete cosine transform (DCT) hardware unit may implement these techniques to transform media data from a spatial domain to a frequency domain. The 8-point DCT hardware unit includes an even portion comprising factors A, B that are related to a first scaled factor (μ) in accordance with a first relationship. The 8-point DCT hardware unit also includes an odd portion comprising third, fourth, fifth and sixth internal factors (G, D, E, Z) that are related to a second scaled factor (η) in accordance with a second relationship. The first relationship relates the first scaled factor to the first and second internal factors. The second relationship relates the second scaled factor to the third internal factor and a fourth internal factor, as well as, the fifth internal factor and a sixth internal factor. | 06-23-2011 |
| 20110150079 | 16-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing a 16-point discrete cosine transform (DCT) that is capable of applying multiple IDCT of different sizes. For example, an apparatus comprising a 16-point discrete cosine transform of type II (DCT-II) unit may implement the techniques of this disclosure. The 16-point DCT-II unit performs these DCTs-II of different sizes to transform data from a spatial to a frequency domain. The 16-point DCT-II unit includes an 8-point DCT-II unit that performs one of the DCTs-II of size 8 and a first 4-point DCT-II unit that performs one of the DCTs-II of size 4. The 8-point DCT-II unit includes the first 4-point DCT-II unit. The 16-point DCT-II unit also comprises an 8-point DCT-IV unit that includes a second 4-point DCT-II unit and a third 4-point DCT-II unit. Each of the second and third 4-point DCT-II units performs one of the DCTs-II of size 4. | 06-23-2011 |
| 20110153699 | 16-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing a 16-point inverse discrete cosine transform (IDCT) that is capable of applying multiple IDCTs of different sizes. For example, an apparatus comprising a 16-point inverse discrete cosine transform of type II (IDCT-II) unit may implement the techniques of this disclosure. The 16-point IDCT-II unit performs these IDCTs-II of different sizes to transform data from a spatial to a frequency domain. The 16-point IDCT-II unit includes an 8-point IDCT-II unit that performs one of the IDCTs-II of size 8 and a first 4-point IDCT-II unit that performs one of the IDCTs-II of size 4. The 8-point IDCT-II unit includes the first 4-point DCT-II unit. The 16-point IDCT-II unit also comprises an inverse 8-point DCT-IV unit that includes a second 4-point IDCT-II unit and a third 4-point IDCT-II unit. Each of the second and third 4-point IDCT-II units performs one of the IDCTs-II of size 4. | 06-23-2011 |
