Patent application number | Description | Published |
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 |
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 |
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 |
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 |
20130129241 | METHODS AND DEVICES FOR ENCODING AND DECODING TRANSFORM DOMAIN FILTERS - Methods and devices for encoding and decoding data using 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 transform domain reconstructions. Rate-distortion optimization may be used to determine the optimal filter coefficients on a frame-basis, coding-unit-basis, or other basis. Multiple filters may be developed and communicated from the encoder to the decoder for different combinations of transform block size, coding mode, prediction mode, and texture type. In other cases, the filtering is applied in the pixel-domain to a pixel-domain prediction or a pixel-domain reconstruction of a block of samples. | 05-23-2013 |
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 |
20130235936 | MOTION VECTOR SIGN BIT HIDING - Methods of encoding and decoding for video data for encoding or decoding motion vector difference components for inter-coded video are described. The sign of one of the components is hidden within the parity of the sum of the magnitudes of the horizontal and vertical difference components. The sign of the other of the components is explicitly signaled in the bitstream. The hidden sign may be assigned to the larger in magnitude of the two components. In other cases, the hidden sign may always be assigned to the horizontal or vertical component. In another case, the hidden sign may always be assigned to one component, unless that component is zero, in which case the hidden sign is assigned to the other component. In another case, both components may have their signs hidden, in which case the sign hiding is based on their respective parity, rather than the parity of their sum. | 09-12-2013 |
20130241752 | 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. | 09-19-2013 |
20130272384 | MODIFIED CONTEXTS FOR LEVEL CODING OF VIDEO DATA - Methods and devices for reconstructing coefficient levels from a bitstream of encoded video data for a coefficient group in a transform unit, and corresponding methods and devices for encoding are provided. The method of reconstructing includes, for each of the non-zero coefficients in the coefficient group, in scan order, decoding a greater-than-one flag for that non-zero coefficient if fewer than two previously-decoded greater-than-one flags for that coefficient group are equal to one. The coefficient levels for the non-zero coefficients are reconstructed based, at least in part, upon the decoded greater-than-one flags. | 10-17-2013 |
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 |
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 |
20140003533 | REDUCED WORST-CASE CONTEXT-CODED BINS IN VIDEO COMPRESSION WITH PARITY HIDING | 01-02-2014 |
20140064364 | METHODS AND DEVICES FOR INTER-LAYER PREDICTION IN SCALABLE VIDEO COMPRESSION - Methods and devices for encoding and decoding scalable video are described. In one aspect, a method of reconstructing, in a video decoder, an enhancement-layer image based upon a reconstructed reference-layer image using inter-layer prediction is described. The method includes reconstructing a reference-layer residual and a reference-layer prediction, wherein the reference-layer residual and the reference-layer prediction, when combined, form the reconstructed reference-layer image; up-sampling the reference-layer residual using a first up-sampling operation; up-sampling the reference-layer prediction using a second up-sampling operation different from the first up-sampling operation; generating an inter-layer prediction using the up-sampled reference-layer residual and the up-sampled reference-layer prediction; and reconstructing the enhancement-layer image based upon the inter-layer prediction. | 03-06-2014 |
20140064365 | METHODS AND DEVICES FOR ENTROPY CODING IN SCALABLE VIDEO COMPRESSION - Methods and devices for decoding, in a video decoder, a block of enhancement-layer transform domain data for an enhancement-layer encoded video and corresponding to a reconstructed block of reference-layer transform domain data, are provided. The method includes determining a context for an enhancement-layer element based, at least in part, upon elements in the corresponding reconstructed block of reference-layer transform domain data, wherein the elements are identified by a template and wherein the position of the template in the reference-layer reconstructed block is based upon the position of that enhancement-layer element in the block of enhancement-layer transform domain data. | 03-06-2014 |
20140286405 | 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. | 09-25-2014 |
20140307781 | 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. | 10-16-2014 |
20140355674 | 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. | 12-04-2014 |
20140376622 | METHODS AND DEVICES FOR DATA COMPRESSION USING A NON-UNIFORM RECONSTRUCTION SPACE - An encoding method for encoding video data by adjusting a quantization parameter, the video data being partitioned into blocks comprising sets of quantized transform coefficients. The method includes, for a set of quantized transform coefficients corresponding to one of the blocks, collecting statistics, wherein the statistics comprise the number of quantized transform coefficients and the sum of the non-rounded quantization value of the quantized transform coefficients in the set. The method also includes deriving a step size based on the statistics, mapping the derived step size to a closest quantization parameter value, and quantizing a next block using the mapped quantization parameter value. | 12-25-2014 |
20150078432 | CODING POSITION DATA FOR THE LAST NON-ZERO TRANSFORM COEFFICIENT IN A COEFFICIENT GROUP - Methods and devices for video coding are described. When encoding a non-zero coefficient group (CG) prior to the last such group in a group scan ordering within a transform block, data representative of the true (x,y)-position of the last non-zero transform coefficient in a scan ordering within that CG is modified, to improve coding efficiency, based upon at least one of (a) an intra-prediction mode used to encode the block and (b) at least one coefficient group neighbouring that CG. Upon decoding a CG thus encoded, the modification is un-done to retrieve the true (x,y)-position. | 03-19-2015 |
20150078445 | TRANSPOSING A BLOCK OF TRANSFORM COEFFICIENTS, BASED UPON AN INTRA-PREDICTION MODE - Methods and devices for video coding are described. If an intra-prediction mode to be used in encoding a block of residual data is in a specific predetermined class, e.g., the horizontal class, then at least a portion of a quantized transformed block of residual data is transposed during encoding. Likewise, if an intra-prediction mode that was used to generate an encoded block of residual data is in such a class, then at least a portion of an entropy-decoded block of residual data is transposed during decoding. | 03-19-2015 |