Patent application number | Description | Published |
20120082224 | INTRA SMOOTHING FILTER FOR VIDEO CODING - This disclosure relates to techniques for reducing the amount of additional data encoded with a block encoded using intra-predictive coding. Particularly, the techniques provide apparatus and methods of applying a smoothing filter to prediction samples used in intra-predictive coding. For example, in fixed mode-dependent intra-predictive coding, a video encoder may determine the type of smoothing filter applied to prediction samples based on block size and intra-prediction mode combination associated with the current block, where the combination is used to look up a filter in a first filter table. In adaptive mode-dependent intra-predictive coding, the encoder uses two filters, one from the first filter table and another from a second filter table, applies both filters, and determines which yields better results. When the second filter table filter yields better results, the encoder encodes a filtering indication. When a filter from the first filter table is used, no filtering indication is encoded. | 04-05-2012 |
20120287988 | OFFSET TYPE AND COEFFICIENTS SIGNALING METHOD FOR SAMPLE ADAPTIVE OFFSET - This disclosure describes techniques for performing sample adaptive offset signaling and coding in a video coding process. Techniques of the disclosure include both a merge-based and prediction-based signaling process for sample adaptive offset information (i.e., offset values and offset type). The techniques includes determining offset information for a current partition, comparing the offset information of the current partition with offset information of one or more neighbor partitions, coding a merge instruction in the case that the offset information of one of the one or more neighbor partitions is the same as the offset information of the current partition, and coding one of a plurality of prediction instructions in the case that the offset information of the one or more neighbor partitions is not the same as the offset information of the current partition. | 11-15-2012 |
20120287994 | FILTERING BLOCKINESS ARTIFACTS FOR VIDEO CODING - In one example, an apparatus for coding video data includes a video coder configured to determine a first prediction mode for a first block of video data and a second prediction mode for a second block of video data, wherein the first block and the second block share a common edge, decode the first block using the first prediction mode and the second block using the second prediction mode, and determine whether to deblock the common edge between the first block and the second block based at least in part on whether at least one of the first prediction mode and the second prediction mode comprises short distance intra-prediction (SDIP). | 11-15-2012 |
20130022107 | DEBLOCKING OF NON-SQUARE BLOCKS FOR VIDEO CODING - In one example, a video coding device is configured to decode a first block of video data and a second block of video data, wherein the first block and the second block share a common edge, and determine whether to deblock the common edge between the first block and the second block based at least in part on whether at least one of the first block and the second block is non-square. Non-square blocks of video data may comprise, for example, partitions (e.g., prediction units or transform units) resulting from asymmetric motion partitioning, non-square transforms for symmetric motion partitioning, or other quadtree transform splitting procedures. The video coding device may apply adapted deblocking decision functions and/or adapted deblocking filters to the common edge when either or both of the blocks is non-square. | 01-24-2013 |
20130044809 | APPLYING PARTITION-BASED FILTERS - In general, techniques are described for applying partition-based filters when coding video data. A device comprising at least one processor may be configured to implement the techniques. The processor selects a filter to apply near a boundary of a first portion of the video data and determines at least one of the plurality of filter coefficients of the selected filter for which the video data will not be available to be filtered. Based on the determination, the processor determines a partial filter that does not include the at least one of the plurality of filter coefficients for which the video data will not be available to be filtered. The processor renormalizes the plurality of filter coefficients included within the partial filter and applies the renormalized partial filter near the boundary of the first portion of the video data to generate a filtered first portion of the video data. | 02-21-2013 |
20130094572 | PERFORMING TRANSFORM DEPENDENT DE-BLOCKING FILTERING - In general, techniques are described for performing transform dependent de-blocking filtering, which may be implemented by a video encoding device. The video encoding device may apply a transform to a video data block to generate a block of transform coefficients, apply a quantization parameter to quantize the transform coefficients and reconstruct the block of video data from the quantized transform coefficients. The video encoding device may further determine at least one offset used in controlling de-blocking filtering based on the size of the applied transform, and perform de-blocking filtering on the reconstructed block of video data based on the determined offset. Additionally, the video encoder may specify a flag in a picture parameter set (PPS) that indicates whether the offset is specified in one or both of the PPS and a header of an independently decodable unit. | 04-18-2013 |
20130101024 | DETERMINING BOUNDARY STRENGTH VALUES FOR DEBLOCKING FILTERING FOR VIDEO CODING - A video coder associates a first boundary strength value with an edge in response to determining that a first video block or a second video block is associated with an intra-predicted coding unit (CU), where the edge occurs at a boundary between the first video block and the second video block. The video coder may associate a second or a third boundary strength value with the edge when neither the first video block nor the second video block is associated with an intra-predicted CU. The video coder may apply one or more deblocking filters to samples associated with the edge when the edge is associated with the first boundary strength value or the second boundary strength value. The third boundary strength value indicates that the deblocking filters are turned off for the samples associated with the edge. | 04-25-2013 |
20130101025 | INTRA PULSE CODE MODULATION (IPCM) AND LOSSLESS CODING MODE DEBLOCKING FOR VIDEO CODING - Techniques for coding video data include coding a plurality of blocks of video data, wherein at least one block of the plurality of blocks of video data is coded using a coding mode that is one of an intra pulse code modulation (IPCM) coding mode and a lossless coding mode. In some examples, the lossless coding mode may use prediction. The techniques further include assigning a non-zero quantization parameter (QP) value for the at least one block coded using the coding mode. The techniques also include performing deblocking filtering on one or more of the plurality of blocks of video data based on the coding mode used to code the at least one block and the assigned non-zero QP value for the at least one block. | 04-25-2013 |
20130101031 | DETERMINING QUANTIZATION PARAMETERS FOR DEBLOCKING FILTERING FOR VIDEO CODING - A video coder determines a deblocking quantization parameter (QP) value based on at least one of a first QP value and a second QP value. Subsequently, the video coder applies a deblocking filter that is based on the deblocking filter to an edge associated with a first video block. The edge occurs at a boundary between the first video block and a second video block. The first video block is associated with a current coding unit (CU) and the second video block is associated with a neighboring CU. The current CU is included in a first quantization group and the neighboring CU is included in a second quantization group. The first QP value is defined for the first quantization group. The second QP value is defined for the second quantization group. | 04-25-2013 |
20130114708 | SECONDARY BOUNDARY FILTERING FOR VIDEO CODING - In one example, a video coding device is configured to intra-predict a block of video data, using values of pixels along a primary boundary of the block, to form a predicted block, determine whether to filter the predicted block using data of a secondary boundary of the block, and filter the predicted block using data of the secondary boundary in response to determining to filter the predicted block. The video coding device may determine whether to filter the predicted block based on a comparison of a Laplacian value or a gradient difference value to a threshold. The determination of whether to filter the predicted block may be based at least in part on a boundary relationship, e.g., the relationship of one boundary to another, or of a boundary to pixel values of the predicted block. | 05-09-2013 |
20130170562 | DEBLOCKING DECISION FUNCTIONS FOR VIDEO CODING - In one example, a video coding device is configured to decode four blocks of video data, wherein the four blocks are non-overlapping and share one common point such that four edge segments are formed by the four blocks, for each of the four edge segments, determine whether to deblock the respective edge segment based on a first analysis of at least one line of pixels that is perpendicular to the respective edge segment and that intersects the respective edge segment, for each of the four edge segments that was determined to be deblocked, determine whether to apply a strong filter or a weak filter to the respective edge segment based on a second analysis of the at least one line of pixels for the respective edge, and deblock the four edge segments based on the determinations. | 07-04-2013 |
20130188733 | SIGNALING OF DEBLOCKING FILTER PARAMETERS IN VIDEO CODING - This disclosure describes techniques for signaling deblocking filter parameters for a current slice of video data with reduced bitstream overhead. Deblocking filter parameters may be coded in one or more of a picture layer parameter set and a slice header. The techniques reduce a number of bits used to signal the deblocking filter parameters by coding a first syntax element that indicates whether deblocking filter parameters are present in both the picture layer parameter set and the slice header, and only coding a second syntax element in the slice header when both sets of deblocking filter parameters are present. Coding the second syntax element is eliminated when deblocking filter parameters are present in only one of the picture layer parameter set or the slice header. The second syntax element indicates which set of deblocking filter parameters to use to define a deblocking filter applied to a current slice. | 07-25-2013 |
20130188744 | DEBLOCKING CHROMA DATA FOR VIDEO CODING - A video coding device is configured to obtain an array of sample values. The sample values may be formatted according to a 4:2:0, 4:2:2, or 4:4:4 chroma format. The video coding device determines whether to apply a first filter to rows of chroma sample values associated with defined horizontal edges within the array. The video coding device determines whether to apply a second filter to columns of chroma sample values associated with defined vertical edges. The horizontal and vertical edges may be separated by a number of chroma samples according to a deblocking grid. | 07-25-2013 |
20130259120 | QUANTIZATION MATRIX AND DEBLOCKING FILTER ADJUSTMENTS FOR VIDEO CODING - A device may include a video coder configured to determine an equivalent quantization parameter (QP) for a decoded block of video data using a quantization matrix for the decoded block of video data, determine deblocking parameters based on the determined equivalent QP, and deblock an edge of the decoded block based on the determined deblocking parameters. In particular, the video coder may determine equivalent QPs for two neighboring blocks defining a common edge, and deblock the common edge based on the equivalent QPs. The video coder may determine deblocking parameters, such as β and t | 10-03-2013 |
20130259141 | CHROMA SLICE-LEVEL QP OFFSET AND DEBLOCKING - In one example, an apparatus for processing video data comprises a video coder configured to, for each of the one or more chrominance components, calculate a chrominance quantization parameter for a common edge between two blocks of video data based on a first luminance quantization parameter for the first block of video data, a second luminance quantization parameter for the second block of video data, and a chrominance quantization parameter offset value for the chrominance component. The video coder is further configured to determine a strength for a deblocking filter for the common edge based on the chrominance quantization parameter for the chrominance component, and apply the deblocking filter according to the determined strength to deblock the common edge. | 10-03-2013 |
20130271566 | VIEW SYNTHESIS MODE FOR THREE-DIMENSIONAL VIDEO CODING - A video encoder signals, in a bitstream, a syntax element that indicates whether a current video unit is predicted from a VSP picture. The current video unit is a macroblock or a macroblock partition. The video encoder determines, based at least in part on whether the current video unit is predicted from the VSP picture, whether to signal, in the bitstream, motion information for the current video unit. A video decoder decodes the syntax element from the bitstream and determines, based at least in part on the syntax element, whether the bitstream includes the motion information. | 10-17-2013 |
20130272425 | BETA OFFSET CONTROL FOR DEBLOCKING FILTERS IN VIDEO CODING - Techniques are described for providing continuous control of a deblocking filter for a video block using a beta offset parameter. Deblocking filters are defined based on one or more deblocking decisions. Conventionally, a quantization parameter and a beta offset parameter are used to identify a beta parameter (“β”) value that determines threshold values of the deblocking decisions. The value of the beta offset parameter results in a change or increment of the β value. For small increments of the β value, rounding of the threshold values may result in no change and discontinuous control of the deblocking decisions. The techniques include calculating at least one deblocking decision for the deblocking filter according to a threshold value that has been modified based on a multiplier value of the beta offset parameter. The multiplier value applied to the beta offset parameter causes an integer change in the modified threshold value. | 10-17-2013 |
20130294524 | TRANSFORM SKIPPING AND LOSSLESS CODING UNIFICATION - An example method includes determining whether an encoded block of residual video data was encoded losslessly in accordance with a lossless coding mode, based on whether transform operations were skipped during encoding of the block of residual video data, and if the block of residual video data was encoded losslessly, then decoding the encoded block of residual video data according to the lossless coding mode to form a reconstructed block of residual video data, where decoding the encoded block of residual data comprises bypassing quantization and sign hiding while decoding the encoded block of residual video data, and bypassing all loop filters with respect to the reconstructed block of residual video data. | 11-07-2013 |
20130336395 | UNIFICATION OF SIGNALING LOSSLESS CODING MODE AND PULSE CODE MODULATION (PCM) MODE IN VIDEO CODING - Techniques described herein are related to harmonizing the signaling of coding modes and filtering in video coding. In one example, a method of decoding video data is provided that includes decoding a first syntax element to determine whether PCM coding mode is used for one or more video blocks, wherein the PCM coding mode refers to a mode that codes pixel values as PCM samples. The method further includes decoding a second syntax element to determine whether in-loop filtering is applied to the one or more video blocks. Responsive to the first syntax element indicating that the PCM coding mode is used, the method further includes applying in-loop filtering to the one or more video blocks based at least in part on the second syntax element and decoding the one or more video blocks based at least in part on the first and second syntax elements. | 12-19-2013 |
20130343464 | TRANSFORM SKIP MODE - A device for coding video data includes a video coder configured to: determine for a chroma transform block (TB) a sub-sampling format for the chroma TB; based on the sub-sampling format for the chroma TB, identify one or more corresponding luma TBs; determine, for each of the one or more corresponding luma TBs, if the corresponding luma TB is coded using a transform skip mode; and, based on a number of the one or more corresponding luma TBs coded using the transform skip mode being greater than or equal to a threshold value, determine that the chroma TB is coded in the transform skip mode. | 12-26-2013 |
20140079135 | PERFORMING QUANTIZATION TO FACILITATE DEBLOCKING FILTERING - A method of encoding video data includes encoding a quantization parameter delta value in a coding unit (CU) of the video data before coding a version of a block of the CU in a bitstream so as to facilitate deblocking filtering. Coding the quantization parameter delta value may comprise coding the quantization parameter delta value based on the value of a no_residual_syntax flag that indicates whether no blocks of the CU have residual transform coefficients. | 03-20-2014 |
20140169483 | DEBLOCKING FILTER WITH REDUCED LINE BUFFER - An apparatus configured to filter video information according to certain aspects includes a memory unit and a processor in communication with the memory unit. The memory unit stores video information comprising at least two adjacent video blocks, each video block comprising a plurality of video samples, and each video sample having a bit depth. The processor determines a filtered video sample based at least in part on a video sample and an adjustment value. The processor determines the adjustment value at least in part from an input with a limited bit depth. The input is determined from a set of one or more video samples, and its bit depth is limited such that it is less than the bit depth of the one or more video samples. | 06-19-2014 |
20140185664 | INTER-LAYER PREDICTION USING SAMPLE-ADAPTIVE ADJUSTMENTS FOR BIT DEPTH SCALABLE VIDEO CODING - An apparatus for coding video data according to certain aspects includes a memory unit and a processor in communication with the memory unit. The memory unit stores video data. The video data may include a base layer comprising samples with a lower bit depth and an enhancement layer comprising samples with a higher bit depth. The processor predicts the values of samples in the enhancement layer based on the values of samples in the base layer. The prediction performed by the processor includes applying a preliminary mapping to the base layer samples to obtain preliminary predictions, and then applying adaptive adjustments to the preliminary predictions to obtain refined predictions. Parameters used for the adaptive adjustments may depend on the values and distribution of base layer samples. The processor may encode or decode the video data. | 07-03-2014 |
20140192892 | BLOCKINESS METRIC FOR LARGE HEVC BLOCK ARTIFACTS - In one example, a method for encoding video data includes determining a first value for a line of a first plurality of lines, wherein the first plurality of lines are perpendicular to a first edge of a block of the video data; in response to determining that the value satisfies at least one threshold: determining a second value for the line of the first plurality of lines; and determining a second value for a line of a second plurality of lines, wherein the second plurality of lines are perpendicular to a second edge of the block of video data; determining, based on the second value for the line of the first plurality of lines and the second value for the line of the second plurality of lines, an average value; and determining, based on the average value, whether or not to encode one or more deblocking parameter offsets. | 07-10-2014 |
20140241417 | OFFSET TYPE AND COEFFICIENTS SIGNALING METHOD FOR SAMPLE ADAPTIVE OFFSET - This disclosure describes techniques for performing sample adaptive offset signaling and coding in a video coding process. Techniques of the disclosure include both a merge-based and prediction-based signaling process for sample adaptive offset information (i.e., offset values and offset type). The techniques includes determining offset information for a current partition, comparing the offset information of the current partition with offset information of one or more neighbor partitions, coding a merge instruction in the case that the offset information of one of the one or more neighbor partitions is the same as the offset information of the current partition, and coding one of a plurality of prediction instructions in the case that the offset information of the one or more neighbor partitions is not the same as the offset information of the current partition. | 08-28-2014 |
20140369404 | SIGNALING OF DEBLOCKING FILTER PARAMETERS IN VIDEO CODING - This disclosure describes techniques for signaling deblocking filter parameters for a current slice of video data with reduced bitstream overhead. Deblocking filter parameters may be coded in one or more of a picture layer parameter set and a slice header. The techniques reduce a number of bits used to signal the deblocking filter parameters by coding a first syntax element that indicates whether deblocking filter parameters are present in both the picture layer parameter set and the slice header, and only coding a second syntax element in the slice header when both sets of deblocking filter parameters are present. Coding the second syntax element is eliminated when deblocking filter parameters are present in only one of the picture layer parameter set or the slice header. The second syntax element indicates which set of deblocking filter parameters to use to define a deblocking filter applied to a current slice. | 12-18-2014 |
20150085935 | SUB-PREDICTION UNIT (PU) BASED TEMPORAL MOTION VECTOR PREDICTION IN HEVC AND SUB-PU DESIGN IN 3D-HEVC - Techniques are described for sub-prediction unit (PU) based motion prediction for video coding in HEVC and 3D-HEVC. In one example, the techniques include an advanced temporal motion vector prediction (TMVP) mode to predict sub-PUs of a PU in single layer coding for which motion vector refinement may be allowed. The advanced TMVP mode includes determining motion vectors for the PU in at least two stages to derive motion information for the PU that includes different motion vectors and reference indices for each of the sub-PUs of the PU. In another example, the techniques include storing separate motion information derived for each sub-PU of a current PU predicted using a sub-PU backward view synthesis prediction (BVSP) mode even after motion compensation is performed. The additional motion information stored for the current PU may be used to predict subsequent PUs for which the current PU is a neighboring block. | 03-26-2015 |