# Dake He, Waterloo CA

## Dake He, Waterloo CA

Patent application number | Description | Published |
---|---|---|

20090323798 | METHOD AND SYSTEM FOR LOW-COMPLEXITY SLEPIAN-WOLF RATE ESTIMATION IN WYNER-ZIV VIDEO ENCODING - A method and system for low-complexity Slepian-Wolf rate estimator in a hybrid Wyner-Ziv video encoder determines the minimum Slepian-Wolf code rate required to allow correct decoding. The Slepian-Wolf estimator does not assume ideality of source and side-information statistics and does not require the presence of a feedback channel from the decoder to the encoder in order to determine the correct Slepian-Wolf coding rate. Instead, it adapts to the statistical properties of the video steam. The Slepian-Wolf estimator provides very efficient compression performance while avoiding Slepian-Wolf decoding failures. | 12-31-2009 |

20100095116 | Method and System for Secure Collaboration Using Slepian-Wolf Codes - A method and system provide for secure sharing of arbitrary data between users with limited mutual trust. A user can encode its information by using a Slepian-Wolf code at a rate which enables a second user to correctly decode only if the side-information it has satisfies a conditional entropy constraint. The key advantages are as follows. Firstly, it is very flexible, in that it enables secure sharing for general data including multimedia data. Secondly, by appropriate Slepian-Wolf code selection, it enables compression in conjunction with security. Thirdly, it can be used for the case where the data model is imperfectly known and trust is to be built up incrementally. | 04-15-2010 |

20100123607 | METHOD AND SYSTEM FOR EFFICIENT DATA TRANSMISSION WITH SERVER SIDE DE-DUPLICATION - The invention provides a method and system for reducing redundant data blocks. The method includes encoding a first data block having a first length into a bitstream having a second length, transmitting the bitstream to a server device, and reducing redundant data blocks by decoding the first data block from a first plurality of data blocks and the bitstream where each block in the first plurality of data blocks has a length equal to the first length. | 05-20-2010 |

20100188273 | METHOD AND SYSTEM FOR EFFICIENT DATA TRANSMISSION WITH SERVER SIDE DE-DUPLICATION - The invention provides a method and system for reducing redundant data blocks. The method includes reducing redundant data blocks by decoding a first data block from a first plurality of data blocks and a bitstream. | 07-29-2010 |

20100208804 | MODIFIED ENTROPY ENCODING FOR IMAGES AND VIDEOS - A method and encoder for entropy encoding image data using a dynamically determined coding order, and a method and decoder for entropy decoding encoded data encoded using a dynamically determined coding order. The coding order for encoding quantized transform domain coefficients is dynamically determined for the image based on at least one characteristic of the quantized transform domain coefficients. The characteristic may be quantization step size if non-uniform quantization is employed for blocks of data. | 08-19-2010 |

20100208805 | ADAPTIVE QUANTIZATION WITH BALANCED PIXEL-DOMAIN DISTORTION DISTRIBUTION IN IMAGE PROCESSING - Methods and encoders and decoders for adaptively quantizing transform domain coefficients in image and/or video encoding/decoding. For an image having a number of blocks, each block having N coefficients, the quantization step size for each coefficient is selected dynamically, thus resulting in a quantizer that may apply different step sizes to different coefficients. The selected step sizes for each coefficient are used for those coefficients within all blocks in the image/frame. In one aspect, the step sizes are selected on the basis of balancing pixel domain distortion when the image/frame is decoded. | 08-19-2010 |

20100208806 | IN-LOOP DEBLOCKING FOR INTRA-CODED IMAGES OR FRAMES - Methods and encoders/decoders for applying in-loop deblocking to intra-coded images/frames. In a decoding context, a deblocking filter is applied to reconstructed pixels of an intra-coded block prior to decoding the subsequent block in the decoding sequence. In an encoding context, a deblocking filter is applied to reconstructed pixels of an intra-coded block in an inter-coding loop before encoding a subsequent block in the coding order for the image. | 08-19-2010 |

20110116545 | METHODS AND DEVICES FOR IN-LOOP VIDEO DEBLOCKING - A video encoder sends at least some information regarding boundary strength to the decoder along with the bitstream of encoded video. The decoder is configured to use the received boundary strength information from the encoder to reduce the number of computations necessary for the decoder to determine the boundary strength details required for performing deblocking when decoding the bitstream. | 05-19-2011 |

20110170595 | METHOD AND DEVICE FOR MOTION VECTOR PREDICTION IN VIDEO TRANSCODING USING FULL RESOLUTION RESIDUALS - A transcoder and methods of encoding inter-prediction frames of a downsampled video wherein the downsampled video is a spatially downsampled version of a full-resolution video. Full-resolution motion vectors are downscaled and a weighting factor is calculated for each downscaled motion vector based upon the transform domain residual coefficients associated with that full-resolution motion vector. A motion vector prediction is made based on the weighted average using the downscaled motion vectors and their weighting factors. | 07-14-2011 |

20110170596 | METHOD AND DEVICE FOR MOTION VECTOR ESTIMATION IN VIDEO TRANSCODING USING UNION OF SEARCH AREAS - A transcoder and methods of encoding inter-prediction frames of a downsampled video wherein the downsampled video is a spatially downsampled version of a full-resolution video. Full-resolution motion vectors are downscaled and each downscaled motion vector pinpoints a search area within a reference frame. The union or combination of search areas defines the search field for candidate motion vectors. A motion vector is selected from the candidates based on realizing a minimum rate-distortion cost. | 07-14-2011 |

20110170597 | METHOD AND DEVICE FOR MOTION VECTOR ESTIMATION IN VIDEO TRANSCODING USING FULL-RESOLUTION RESIDUALS - A transcoder and method of transcoding in which inter-prediction frames of a downsampled video are encoded using downsampled full-resolution residuals in the rate-distortion analysis used to locate a motion vector for a given partition in the downsampled video. | 07-14-2011 |

20110170598 | METHOD AND DEVICE FOR VIDEO ENCODING USING PREDICTED RESIDUALS - An encoder for encoding a video by performing motion estimation using predicted residuals in the rate-distortion cost expression. The predicted residuals are determined by finding a predicted motion vector with respect to the original reference frame and calculating the corresponding residual values. The actual motion vector is then selected based on minimization of the rate-distortion cost expression with respect to the reconstructed reference frame, where the rate-distortion cost expression includes the predicted residuals. In particular, the cost expression includes reconstructed predicted residuals within the distortion term. | 07-14-2011 |

20110170608 | METHOD AND DEVICE FOR VIDEO TRANSCODING USING QUAD-TREE BASED MODE SELECTION - An encoder for encoding a downsampled video in which macroblock partitioning is based upon downsampled partitioning of full-resolution macroblocks. The refinement of the downsampled partitioning involves storing the downsampled partitioning in a quad-tree data structure and recursively identifying and evaluating possible mergers of leaf nodes having a common parent node. Using rate-distortion analysis possible mergers are evaluated and advantageous mergers are performed, thereby creating larger partitions and new leaf nodes. The traversing of the quad-tree to identify possible leaf node mergers is stopped when no further possible mergers may be identified that would result in a rate-distortion advantage. | 07-14-2011 |

20110184733 | SYSTEM AND METHOD FOR ENCODING AND DECODING PULSE INDICES - Methods, and corresponding codec-containing devices are provided that have source coding schemes for encoding a component of an excitation. In some cases, the source coding scheme is an enumerative source coding scheme, while in other cases the source coding scheme is an arithmetic source coding scheme. In some cases, the source coding schemes are applied to encode a fixed codebook component of the excitation for a codec employing codebook excited linear prediction, for example an AMR-WB (Adaptive Multi-Rate-Wideband) speech codec. | 07-28-2011 |

20110200101 | METHOD AND ENCODER FOR CONSTRAINED SOFT-DECISION QUANTIZATION IN DATA COMPRESSION - A method of encoding a video using constrained soft-decision quantization. The soft-decision quantization includes first performing hard-decision quantization to obtain hard quantized coefficients and, then, obtaining a soft quantized coefficient using a rate-distortion calculation over a search range of quantization levels for a transform domain coefficient, wherein the search range of quantization levels for that transform domain coefficient is constrained within a number of quantization levels of a corresponding hard quantized coefficient. The search range may be based upon a fixed threshold, the coefficient position, the hard quantized coefficient magnitude, a threshold value less accumulated distortion, or other factors, including combinations of these factors. The accumulated distortion may be measured by an L1 norm. | 08-18-2011 |

20110200104 | PARALLEL ENTROPY CODING AND DECODING METHODS AND DEVICES - A method for entropy coding data using parallel entropy coders to encode an input sequence as a plurality of encoded subsequences, which are then combined to form an output bitstream. The input sequence is separated into subsequences on the basis of a context model. A method for entropy decoding a bitstream of encoded data by extracting a plurality of encoded subsequences from the bitstream and entropy decoding the encoded subsequences in parallel to generate a plurality of decoded subsequences, which are then interleaved based on a context model to produce a reconstructed sequence. | 08-18-2011 |

20110210873 | ENCODING AND DECODING METHODS AND DEVICES USING A SECONDARY CODEWORD INDICATOR - A method for encoding an input sequence of symbols as a plurality of codewords including primary codewords and secondary codewords, and a method of decoding the plurality of codewords. The codewards are output as a bitstream including an associated codeword type indicator, which specifies whether its associated plurality of consecutive codewords includes at least one secondary codeword and, if so, the location of the first of the at least one secondary codewords. The decoder selects between a primary codeword decoding tree and a secondary codeword decoding tree, and decodes one of the plurality of codewords using the selected decoding tree. | 09-01-2011 |

20110210874 | METHOD AND DEVICE FOR BUFFER-BASED INTERLEAVED ENCODING OF AN INPUT SEQUENCE - A method for encoding an input sequence of symbols. The method includes, sequentially, for each symbol in the input sequence, determining an estimated probability for that symbol based on a context model, identifying a codeword associated with a sequence of symbols resulting from appending that symbol to a previous sequence of symbols associated with that estimated probability, using an encoding tree associated with that estimated probability, and storing the codeword in a buffer element of a first-in-first-out buffer, wherein the buffer element is associated with the estimated probability. Stored codewords are output from the buffer in a first-in-first-out order. | 09-01-2011 |

20110248872 | METHODS AND DEVICES FOR LOAD BALANCING IN PARALLEL ENTROPY CODING AND DECODING - Devices and methods for entropy decoding a bitstream of encoded data by extracting a plurality of encoded subsequences from a payload field of the bitstream for parallel decoding on a set of parallel entropy decoders. The method includes dividing the payload of concatenated encoded subsequences into segments using a distribution function and distributing the segments amongst the set of parallel entropy decoders to balance the computational load among the parallel entropy decoders. The received bitstream includes auxiliary information inserted by the encoder to enable the decoder to entropy decode segments that begin with a portion of an encoded subsequence. | 10-13-2011 |

20110249748 | METHODS AND DEVICES FOR INCORPORATING DEBLOCKING INTO ENCODED VIDEO - Encoders and methods of encoding that incorporate deblocking into the encoding process. An encoder performs a two-cycle encoding process. First, an original block is processed and then reconstructed and deblocked. The reconstruction and the deblocked reconstruction are compared to the original and an intermediate block is created that contains the portions of the reconstruction or the deblocked reconstruction that are more similar to the original. In the second cycle, the intermediate block serves to generate a modified original block, which is then used in a prediction process to create a new prediction block. The new prediction block as compared to the original gives new residuals. The new prediction and new residuals are entropy coded to generate the encoded video data. The new prediction block and new residuals incorporate the deblocking elements selectively identified during the first cycle, thereby eliminating the need for deblocking at the decoder. The prediction operation may be motion prediction or spatial prediction. | 10-13-2011 |

20110254712 | METHODS AND DEVICES FOR REORDERED PARALLEL ENTROPY CODING AND DECODING - A method for parallel context modeling through reordering the bits of an input sequence to form groups of bits in accordance with a context model-specific reordering schedule. The reordering schedule is developed such that the groups of bits are formed to satisfy two conditions: first, that the context for each of the bits in a group of bits is different from the context of each of the other bits in that group, and the context of each of the bits in that group is determined independently from each of the other bits in that group. The parallel context modeling may be used in encoding or decoding operations. | 10-20-2011 |

20110267208 | ENCODING AND DECODING METHODS AND DEVICES EMPLOYING DUAL CODESETS - A method for encoding an input sequence of symbols to produce a bitstream and a method of decoding the bitstream to generate a reconstructed binary sequence. Encoding employs an encoding tree having primary codewords associated with leaf nodes and secondary codewords associated with internal nodes. A flush event may cause output of secondary codewords. A context model is used to select an encoding tree corresponding to an estimated probability at the encoder. The same context model is used by the decoder to select a decoding tree. The decoder interleaves bits from decoded bit sequences associated with different estimated probabilities based on the context model. | 11-03-2011 |

20110285557 | METHODS AND DEVICES FOR REDUCING SOURCES IN BINARY ENTROPY CODING AND DECODING - Methods and systems are described for combining sources in a data compression system. In a system in which a context model results in the production of multiple sources or symbols, each source being associated with a probability estimate, sources may be combined by defining another, reduced size, set of probabilities. The new set of probabilities may be a subset of the predefined set of probabilities provided by the context model. Minimizing relative entropy may be a basis upon which to define a mapping of predefined probabilities to the new set of probabilities. An input sequence that was modeled using the context model may then be entropy encoded and entropy decoded using the new set of probabilities based on a mapping between the new probabilities and the predefined probabilities. | 11-24-2011 |

20110291867 | ENCODING AND DECODING METHODS AND DEVICES USING A SECONDARY CODEWORD INDICATOR - A method for encoding an input sequence of symbols as a plurality of codewords including primary codewords and secondary codewords, and a method of decoding the plurality of codewords. The codewords are output as a bitstream including an associated codeword type indicator, which specifies whether its associated plurality of consecutive codewords includes at least one secondary codeword and, if so, the location of the first of the at least one secondary codewords. The decoder selects between a primary codeword decoding tree and a secondary codeword decoding tree, and decodes one of the plurality of codewords using the selected decoding tree. | 12-01-2011 |

20120008680 | METHODS AND DEVICES FOR DATA COMPRESSION USING ADAPTIVE RECONSTRUCTION LEVELS - Encoding and decoding methods that perform quantization using adaptive reconstruction levels are presented. The reconstruction levels for a given partitioning of the data space may be selected based upon the distribution of data points within each sub-part defined by the partitioning. In some cases, the adaptive reconstruction levels may be based upon an average of the data points within each sub-part. In some cases, the adaptive reconstruction levels may be selected using a rate-distortion analysis including the quantization distortion associated with the levels versus the data points and the rate associated with transmitting the encoded adaptive reconstruction levels. The methods relate to data compression in a range of applications including audio, images and video. | 01-12-2012 |

20120014457 | METHODS AND DEVICES FOR DATA COMPRESSION USING CONTEXT-BASED CODING ORDER - A method is presented for entropy coding data using an entropy coder to encode an input sequence. A context model is used to determine the context of each symbol and a probability estimation is made for each symbol. A method is presented for revising the coding order to be context-based, grouping symbols consecutively on the basis that they have a common context. A method is presented for entropy decoding a bitstream of encoded data encoded using a context-based coding order. | 01-19-2012 |

20120026020 | METHOD AND DEVICE FOR COMPRESSION OF BINARY SEQUENCES BY GROUPING MULTIPLE SYMBOLS - A method for encoding an input sequence of symbols to produce a bitstream and a method of decoding the bitstream to generate a reconstructed binary sequence. Encoding employs 2 | 02-02-2012 |

20120063691 | METHODS AND DEVICES FOR DATA COMPRESSION WITH ADAPTIVE FILTERING IN THE TRANSFORM DOMAIN - Methods and devices for encoding and decoding data using adaptive transform domain filtering are described. The encoder determines a set of transform domain filter coefficients to be applied to a transform domain prediction. The filtering may, in some cases, also apply to quantized transform domain coefficients. Rate-distortion optimization may be used to determine the optimal filter coefficients on a frame-based, coding-unit-basis, or other basis. | 03-15-2012 |

20120081242 | METHODS AND DEVICES FOR PARALLEL ENCODING AND DECODING USING A BITSTREAM STRUCTURED FOR REDUCED DELAY - Methods and devices for encoding and decoding that involve sorting bins according to their respective estimated probabilities to form subsequences, each subsequence having an associated estimated probability. Subsequences are encoded to form codewords. Ordered sets of phrases of known length are then formed from the codewords. Each first of the phrases in a set contains at least part of one codeword. The first phrase has an associated estimated probability and the probability estimates associated with each of the other phrases in the set are determined based upon the probability estimate associated with the first phrase, which permits the phrases to be decoded in parallel. | 04-05-2012 |

20120093220 | IN-LOOP DEBLOCKING FOR INTRA-CODED IMAGES OR FRAMES - Methods and encoders/decoders for applying in-loop deblocking to intra-coded images/frames. In a decoding context, a deblocking filter is applied to reconstructed pixels of an intra-coded block prior to decoding the subsequent block in the decoding sequence. In an encoding context, a deblocking filter is applied to reconstructed pixels of an intra-coded block in an inter-coding loop before encoding a subsequent block in the coding order for the image. | 04-19-2012 |

20120098682 | METHOD AND DEVICE FOR BUFFER-BASED INTERLEAVED ENCODING OF AN INPUT SEQUENCE - A method for encoding an input sequence of symbols. The method includes, sequentially, for each symbol in the input sequence, determining an estimated probability for that symbol based on a context model, identifying a codeword associated with a sequence of symbols resulting from appending that symbol to a previous sequence of symbols associated with that estimated probability, using an encoding tree associated with that estimated probability, and storing the codeword in a buffer element of a first-in-first-out buffer, wherein the buffer element is associated with the estimated probability. Stored codewords are output from the buffer in a first-in-first-out order. | 04-26-2012 |

20120170647 | CODING OF RESIDUAL DATA IN PREDICTIVE COMPRESSION - Encoding input data including one or more frames includes: generating a residual block based on a difference between a first block of data for multiple pixels in a first frame and a second block of data derived from information in the input data; generating a first block of coefficients based on a transform performed on the residual block; generating reference information based on the second block of data; and determining portions of a code value representing respective portions of the first block of coefficients based on at least one value derived from at least a portion of the reference information. | 07-05-2012 |

20120170857 | CODING OF RESIDUAL DATA IN PREDICTIVE COMPRESSION - Encoding input data includes: generating a first block of coefficients based on a transform performed on a residual block of data for multiple pixels; generating reference information based on a reference block of data corresponding to the residual block of data; and determining losslessly decodable code values representing the first block of coefficients based on the reference information. | 07-05-2012 |

20120183056 | METHOD AND DEVICE FOR IMPROVED MULTI-LAYER DATA COMPRESSION - An encoder and method for encoding data in a scalable data compression format are described. In particular, process for encoding spatially scalable video are described in which the base layer uses downscaled residuals from a full-resolution encoding of the video in its motion estimation process. The downscaled residuals may also be used in the coding mode selection process at the base layer. | 07-19-2012 |

20120194363 | METHODS AND DEVICES FOR LOAD BALANCING IN PARALLEL ENTROPY CODING AND DECODING - Devices and methods for entropy decoding a bitstream of encoded data by extracting a plurality of encoded subsequences from a payload field of the bitstream for parallel decoding on a set of parallel entropy decoders. The method includes dividing the payload of concatenated encoded subsequences into segments using a distribution function and distributing the segments amongst the set of parallel entropy decoders to balance the computational load among the parallel entropy decoders. The received bitstream includes auxiliary information inserted by the encoder to enable the decoder to entropy decode segments that begin with a portion of an encoded subsequence. | 08-02-2012 |

20120219055 | METHODS AND DEVICES FOR DATA COMPRESSION USING OFFSET-BASED ADAPTIVE RECONSTRUCTION LEVELS - Encoding and decoding methods are presented that used offset-based adaptive reconstruction levels. The offset data is inserted in the bitstream with the encoded video data. The offset data may be differential data and may be an index to an array of offset values from which the differential offset is calculated by the decoder. The offset to an adaptive reconstruction level may be adjusted for each slice. The offsets may be specific to a particular level/index and data type. In some cases, offsets may only be sent for a subset of the levels. Higher levels may apply no offset, may apply an average offset, or may apply the offset used for the highest level having a level-specific offset. | 08-30-2012 |

20120230422 | Method and System Using Prediction and Error Correction for the Compact Representation of Quantization Matrices In Video Compression - In some implementations, a method for encoding data comprising a matrix of elements for scaling transform coefficients before quantization of the scaled transform coefficients includes generating a sequence of values from the elements of the matrix according to a predetermined order. A plurality of adjacent values in the sequence is generated from respective elements of the matrix. A representation of the data is encoded based at least in part on encoding repeated instances of a specified series of two or more values in the sequence as a corresponding symbol not appearing in the sequence. | 09-13-2012 |

20120262313 | METHODS AND DEVICES FOR CODING AND DECODING THE POSITION OF THE LAST SIGNIFICANT COEFFICIENT - Methods and devices are described for entropy coding data using an entropy coder to encode quantized transform domain coefficient data. Last significant coefficient information is signaled in the bitstream using two-dimensional coordinates for the last significant coefficient. The context for bins of one of the coordinates is based, in part, upon the value of the other of the coordinates. In one case, instead of signaling last significant coefficient information, the number of non-zero coefficients is binarized and entropy encoded. | 10-18-2012 |

20120314760 | METHOD AND SYSTEM TO REDUCE MODELLING OVERHEAD FOR DATA COMPRESSION - A method for decoding compressed data that has been encoded using a context model, each context having a context state corresponding to a probability estimate. Each bin of the data has been encoded using the probability estimate corresponding to the context state for the context associated with that bin. At the decoder, for decoding a series of bins associated with a given context, an initial probability estimate is determined using an initial context state for the given context and the series of bins are decoded and reconstructed using that initial probability estimate. After the series is decoded, the context state is updated based on the reconstructed bins for the series to produce an updated context state for that context to be used in decoding a subsequence portion of the bitstream. | 12-13-2012 |

20120328001 | COMPRESSING IMAGE DATA - Methods, systems, and computer programs for encoding and decoding image are described. In some aspects, an input data block and a prediction data block are accessed. A projection factor is generated based on a projection of the input data block onto the prediction data block. A scaled prediction data block is generated by multiplying the projection factor by the prediction data block. A residual data block is generated based on a difference between the input data block and the scaled prediction data block. In some aspects, a prediction data block, a residual data block, and a projection factor associated with the residual data block are accessed. A scaled prediction data block is generated by multiplying the projection factor by the prediction data block. An output data block is generated by summing the residual data block and the scaled prediction data block. | 12-27-2012 |

20120328204 | COMPRESSING IMAGE DATA - Methods, systems, and computer programs for encoding and decoding image are described. In some aspects, an input data block and a prediction data block are accessed. A projection factor is generated based on a projection of the input data block onto the prediction data block. A scaled prediction data block is generated by multiplying the projection factor by the prediction data block. A residual data block is generated based on a difference between the input data block and the scaled prediction data block. In some aspects, a prediction data block, a residual data block, and a projection factor associated with the residual data block are accessed. A scaled prediction data block is generated by multiplying the projection factor by the prediction data block. An output data block is generated by summing the residual data block and the scaled prediction data block. | 12-27-2012 |

20130022099 | ADAPTIVE FILTERING BASED ON PATTERN INFORMATION - Encoding video data that includes a frame includes: generating a reconstructed frame from compressed data for the frame, partitioning at least some pixels of the reconstructed frame into a plurality of segments of one or more pixels, based at least in part on pattern information for individual pixels, and generating respective filter information for each of one or more of the plurality of segments. Encoded video data is generated that includes the compressed data for the frame and the generated filter information. | 01-24-2013 |

20130083845 | METHODS AND DEVICES FOR DATA COMPRESSION USING A NON-UNIFORM RECONSTRUCTION SPACE - Encoding and decoding methods are presented that use adaptive reconstruction levels. Reconstruction space parameters are developed by an encoder and inserted in the bitstream with the encoded video data. The reconstruction space parameter may include parameters from which the decoder can determine the levels for dequantization of the encoded video data. The reconstruction space parameters may include a first reconstruction level and a step size between other levels. The first reconstruction level may not equal the step size. In some cases, neither may be equal to the quantization step size used to quantize the transform domain coefficients. | 04-04-2013 |

20130101046 | SIGNIFICANCE MAP ENCODING AND DECODING USING PARTITION SELECTION - Methods of encoding and decoding for video data are describe in which significance maps are encoded and decoded using non-spatially-uniform partitioning of the map into parts, wherein the bit positions within each part are associated with a given context. Example partition sets and processes for selecting from amongst predetermined partition sets and communicating the selection to the decoder are described. | 04-25-2013 |

20130128985 | MULTI-LEVEL SIGNIFICANCE MAP SCANNING - Methods of encoding and decoding for video data are described in which multi-level significance maps are used in the encoding and decoding processes. The significant-coefficient flags that form the significance map are grouped into contiguous groups, and a significant-coefficient-group flag signifies for each group whether that group contains no non-zero significant-coefficient flags. A multi-level scan order may be used in which significant-coefficient flags are scanned group-by-group. The group scan order specifies the order in which the groups are processed, and the scan order specifies the order in which individual significant-coefficient flags within the group are processed. The bitstream may interleave the significant-coefficient-group flags and their corresponding significant-coefficient flags, if any. | 05-23-2013 |

20130188724 | METHODS AND SYSTEMS FOR PIPELINING WITHIN BINARY ARITHMETIC CODING AND DECODING - Methods of encoding and decoding for video data are described for encoding or decoding multi-level significance maps whilst enabling pipelining of the BAC engine. In one example, coefficient groups are redefined to remove the significant-coefficient flags of the first and last position of a block and replace them with significant-coefficient flags of the last position in the previous block and the first position in the next block. A modified scan order is applied to each coefficient group. In another example, the coefficient groups remain block-based, but the scan order is modified to interleave the encoding and decoding sequential coefficient groups. | 07-25-2013 |

20130188725 | MULTIPLE SIGN BIT HIDING WITHIN A TRANSFORM UNIT - Methods of encoding and decoding for video data are described for encoding or decoding coefficients for a transform unit. In particular, the sign bits for the non-zero coefficients are encoded using sign bit hiding. Two or more sets of coefficients are defined for the transform unit and a sign bit may be hidden for each set, subject to satisfaction of a threshold test. The sets may correspond to coefficient groups that are otherwise used in multi-level significance map encoding and decoding. | 07-25-2013 |

20130188726 | METHODS AND DEVICES FOR CONTEXT SET SELECTION - Methods of encoding and decoding for video data are described for encoding or decoding multi-level significance maps. Distinct context sets may be used for encoding the significant-coefficient flags in different regions of the transform unit. In a fixed case, the regions are defined by coefficient group borders. In one example, the upper-left coefficient group is a first region and the other coefficient groups are a second region. In a dynamic case, the regions are defined by coefficient group borders, but the encoder and decoder dynamically determine in which region each coefficient group belongs. Coefficient groups may be assigned to one region or another based on, for example, whether their respective significant-coefficient-group flags were inferred or not. | 07-25-2013 |

20130188735 | METHODS AND DEVICES FOR CONTEXT MODELING TO ENABLE MODULAR PROCESSING - Methods of encoding and decoding for video data are described for encoding or decoding coefficients for a transform unit. In particular, the significant-coefficient flags for a coefficient group are encoded and decoded based upon a context determination, and the context is determined based upon the values of neighboring flags. The neighborhood used to determine the context varies depending on whether the significant-coefficient flag to be encoded or decoded is in the right column or bottom row of the coefficient group or not. If it is in the right column or bottom row one of the alternative context neighborhoods is used to avoid relying on significant-coefficient flags in other coefficient groups except for the flags immediately adjacent the right border and bottom border of the coefficient group, and the flag diagonally to the lower-right. | 07-25-2013 |

20130195200 | METHODS AND DEVICES FOR CONTEXT MODELING TO ENABLE MODULAR PROCESSING - Methods of encoding and decoding for video data are described for encoding or decoding coefficients for a transform unit. In particular, the significant-coefficient flags for a coefficient group are encoded and decoded based upon a context determination, and the context is determined based upon the values of neighboring flags. The neighborhood used to determine the context varies depending on whether the significant-coefficient flag to be encoded or decoded is in the two right columns or two bottom rows of the coefficient group or not. The upper-left corner may also have a different neighborhood. If the flag is in one of the two right columns or two bottom rows one of the alternative context neighborhoods is used to avoid relying on significant-coefficient flags in other coefficient groups. | 08-01-2013 |

20130235925 | UNIFIED TRANSFORM COEFFICIENT ENCODING AND DECODING - Methods and devices for reconstructing coefficient levels from a bitstream of encoded video data for a coefficient group in a transform unit, using adaptive-threshold-based level coding. Threshold is set based upon level information from one or more previously-reconstructed coefficient groups in the transform unit. Threshold may be maximum number of level flags to decode for the coefficient group. Level information may include number of level flags decoded in previous coefficient groups. Previously-reconstructed coefficient groups may include coefficient group to the right and below the current coefficient group. | 09-12-2013 |

20130336409 | MULTI-BIT INFORMATION HIDING USING OVERLAPPING SUBSETS - Methods and devices for reconstructing coefficient levels from a bitstream of encoded video data for a coefficient group in a transform unit. Sign bits are hidden in the parity of partially overlapping subsets of a set of coefficients. This enables the hiding of multiple sign bits per coefficient group. Other information bits may be hidden instead of sign bits in some cases. | 12-19-2013 |

20130336410 | METHODS AND DEVICES FOR CODING BINARY SYMBOLS AS N-TUPLES - Methods and devices for reconstructing coefficient levels from a bitstream of encoded video data for a coefficient group in a transform unit. Greater-than-one flags are encoded by grouping them into tuples and by encoding a tuple-based value that is a function of the greater-than-one flags within that tuple. The tuple-based value may permit the decoder to infer the greater-than-one flags in some cases, in which case they are not encoded in the bitstream. | 12-19-2013 |

20130343448 | MODIFIED CODING FOR TRANSFORM SKIPPING - Methods and devices for modified coding of blocks of residuals in the case of transform skipping. To better align the data with assumptions upon which the entropy coding scheme is based, the block of residual data is permuted at the encoder prior to entropy coding. The block of reconstructed data is then inverse permuted at the decoder to recover the reconstructed block of residuals. The permutation may include 180 rotation of the block, which may be of particular benefit in the case of intra-coded residuals. | 12-26-2013 |