Patent application number | Description | Published |
20120121011 | PARALLEL CONTEXT CALCULATION IN VIDEO CODING - In one example, a method for coding video data includes identifying a scan path for scanning significance information associated with a quantized transform coefficient. The method also includes determining a context support neighborhood for entropy coding the significance information associated with the quantized transform coefficient, wherein the context support neighborhood excludes one or more context support elements that are located in the scan path. The method also includes coding the significance information using the modified context support neighborhood. | 05-17-2012 |
20120140814 | CODING THE POSITION OF A LAST SIGNIFICANT COEFFICIENT WITHIN A VIDEO BLOCK BASED ON A SCANNING ORDER FOR THE BLOCK IN VIDEO CODING - In one example, an apparatus is disclosed for coding coefficients associated with a block of video data during a video coding process, wherein the apparatus includes a video coder configured to code x- and y-coordinates that indicate a position of a last non-zero coefficient within the block according to a scanning order associated with the block when the scanning order comprises a first scanning order, and code interchanged x- and y-coordinates that indicate the position of the last non-zero coefficient within the block according to the scanning order when the scanning order comprises a second scanning order, wherein the second scanning order is different than the first scanning order. | 06-07-2012 |
20120163448 | CODING THE POSITION OF A LAST SIGNIFICANT COEFFICIENT OF A VIDEO BLOCK IN VIDEO CODING - In one example, an apparatus is disclosed for coding coefficients associated with a block of video data during a video coding process, wherein the apparatus includes a video coder configured to code information that identifies a position of a last non-zero coefficient within the block according to a scanning order associated with the block, wherein to code the information, the video coder is configured to perform a context adaptive entropy coding process that includes the video coder applying a context model based on at least three contexts, wherein the at least three contexts include a size associated with the block, a position of a given one of the coefficients within the block according to the scanning order, and the scanning order. | 06-28-2012 |
20120163455 | MODE DEPENDENT SCANNING OF COEFFICIENTS OF A BLOCK OF VIDEO DATA - This disclosure describes apparatuses and methods of encoding coefficients associated with a block of video data. In one example, a method may comprise selecting a scan order for the coefficients based on an intra coding mode used to predict the block of video data and a transform block size used in transforming the block of video data, and generating a syntax element to communicate the selected scan order for the block of video data. | 06-28-2012 |
20120163456 | USING A MOST PROBABLE SCANNING ORDER TO EFFICIENTLY CODE SCANNING ORDER INFORMATION FOR A VIDEO BLOCK IN VIDEO CODING - In one example, an apparatus is disclosed for coding coefficients associated with a block of video data during a video coding process, the apparatus comprising a video coder configured to code information that identifies a scanning order associated with the block, wherein to code the information that identifies the scanning order associated with the block, the video coder is configured to determine a most probable scanning order for the block, and code an indication of whether the scanning order associated with the block is the most probable scanning order. In another example, to code the information that identifies the scanning order associated with the block, the video coder is further configured to, in the event the scanning order associated with the block is not the most probable scanning order, code an indication of the scanning order associated with the block. | 06-28-2012 |
20120163472 | EFFICIENTLY CODING SCANNING ORDER INFORMATION FOR A VIDEO BLOCK IN VIDEO CODING - An apparatus is disclosed for coding coefficients associated with a block of video data, including a video coder configured to code information that identifies a first scanning order associated with the block if a position of any of one or more of the coefficients within the block, starting with a first coefficient within the block and ending with a last non-zero coefficient within the block according to the first scanning order, and proceeding according to the first scanning order, according to the first scanning order is different than a position of the respective coefficient within the block according to a second scanning order, and avoid coding the information if the position of each of the one or more of the coefficients within the block according to the first scanning order is the same as the position of the respective coefficient within the block according to the second scanning order. | 06-28-2012 |
20120170649 | VIDEO CODING USING MAPPED TRANSFORMS AND SCANNING MODES - A video encoder may transform residual data by using a transform selected from a group of transforms. The transform is applied to the residual data to create a two-dimensional array of transform coefficients. A scanning mode is selected to scan the transform coefficients in the two-dimensional array into a one-dimensional array of transform coefficients. The combination of transform and scanning mode may be selected from a subset of combinations that is based on an intra-prediction mode. The scanning mode may also be selected based on the transform used to create the two-dimensional array. The transforms and/or scanning modes used may be signaled to a video decoder. | 07-05-2012 |
20120189049 | SUB-SLICES IN VIDEO CODING - A video encoder partitions a slice of a picture into a plurality of sub-slices. When the video encoder encodes the slice, the video encoder generates a coded slice that includes coded sub-slices that correspond to the sub-slices. Each of the sub-slices can be parsed independently of each other one of the sub-slices and can be reconstructed independently of each other one of the sub-slices. Accordingly, a video decoder may parse two or more of the sub-slices in parallel and decode two or more of the sub-slices in parallel. | 07-26-2012 |
20120189053 | COMBINED REFERENCE PICTURE LIST CONSTRUCTION FOR VIDEO CODING - This disclosure relates to techniques for constructing a combined reference picture list, List C, based on List | 07-26-2012 |
20120195368 | PERFORMING MOTION VECTOR PREDICTION FOR VIDEO CODING - In general, techniques are described for performing motion vector prediction for video coding. An apparatus comprising a motion compensation unit may implement the techniques. The motion compensation unit determines spatial candidate motion vectors (MVPs) associated with a current portion of a video frame and prunes the spatial candidate motion vectors to remove duplicates without removing a temporal candidate motion vector. The motion compensation unit selects one of the temporal candidate motion vector or one of the spatial candidate motion vectors remaining after pruning as a selected candidate motion vector based on a motion vector predictor (MVP) index signaled in a bitstream and performs motion compensation based on the selected candidate motion vector. | 08-02-2012 |
20120230433 | VIDEO CODING TECHNIQUES FOR CODING DEPENDENT PICTURES AFTER RANDOM ACCESS - In general, this disclosure describes techniques for coding video data for random access. In particular, this disclosure proposes to code a syntax element that indicates if a dependent picture may be successfully decoded in the event of a random access request to a clean decoding refresh (CDR) picture and may be required for decoding the pictures following the clean decoding refresh (CDR) picture in display order. | 09-13-2012 |
20120328004 | QUANTIZATION IN VIDEO CODING - In an example, aspects of this disclosure relate to a method of coding video data that includes identifying a plurality of quantization parameter (QP) values associated with a plurality of reference blocks of video data. The method also includes generating a reference QP for the plurality of reference blocks based on the plurality of QPs. The method also includes storing the reference QP, and coding a block of video data based on the stored reference QP. | 12-27-2012 |
20130010865 | REDUCED RESOLUTION PIXEL INTERPOLATION - An offset can be applied to intermediate values obtained while performing an interpolation filtering operation such that applying the offset reduces the bitdepth of the intermediate value. The intermediate value can be stored with the reduced bitdepth, and when retrieved, the offset can be added back such that future calculation can be performed using the intermediate value with the original bitdepth. | 01-10-2013 |
20130083853 | MOTION VECTOR PREDICTOR CANDIDATE CLIPPING REMOVAL FOR VIDEO CODING - This disclosure describes techniques for coding a video block based on an unclipped version of a motion vector predictor candidate. The techniques include determining a motion vector predictor candidate list including motion vector predictor candidates from neighboring video blocks without clipping the motion vector predictor candidates. More specifically, if one of the motion vector predictor candidates points to a prediction block located outside of a reference picture boundary relative to the current video block, the techniques allow an unclipped version of the motion vector predictor candidate to be included in the candidate list. The current video block is then coded based on a determined unclipped motion vector predictor candidate of the candidate list. Elimination of the motion vector predictor candidate clipping process reduces complexity at both the video encoder and the video decoder. | 04-04-2013 |
20130094580 | DETECTING AVAILABILITIES OF NEIGHBORING VIDEO UNITS FOR VIDEO CODING - As part of a video encoding or decoding operation on video data, a video coder performs a coding operation for a current video unit of the video data. As part of performing the coding operation for the current video unit, the video coder determines the availabilities of one or more video units that neighbor the current video unit. In order to determine the availability of a video unit that neighbors the current video unit, the video coder identifies, based on availabilities of video units that neighbor a parent video unit of the current video unit, an entry in a lookup table. The identified entry indicates the availability of the video unit that neighbors the current video unit. The video coder then performs a coding operation on the current video unit based on whether the video unit that neighbors the current video unit is available. | 04-18-2013 |
20130107952 | UNIFIED DESIGN FOR PICTURE PARTITIONING SCHEMES | 05-02-2013 |
20130114736 | PADDING OF SEGMENTS IN CODED SLICE NAL UNITS - A video encoder divides a picture into a plurality of picture partitions, such as tiles or wavefront parallel processing (WPP) waves. The picture partitions are associated with non-overlapping subsets of the treeblocks of the picture. The video encoder generates a coded slice network abstraction layer (NAL) unit that includes encoded representations of the treeblocks associated with a slice of the picture. The coded treeblocks are grouped within the coded slice NAL unit into segments associated with different ones of the picture partitions. The video encoder pads one or more of the segments such that each of the segments begins on a byte boundary. | 05-09-2013 |
20130121417 | CONSTRAINED REFERENCE PICTURE SETS IN WAVE FRONT PARALLEL PROCESSING OF VIDEO DATA - A video encoder determines reference blocks for each inter-predicted prediction unit (PU) of a tree block group such that each of the reference blocks is in a reference picture that is in a reference picture subset for the tree block group. The reference picture subset for the tree block group includes less than all reference pictures in a reference picture set of the current picture. The tree block group comprises a plurality of concurrently-coded tree blocks in the current picture. For each inter-predicted PU of the tree block group, the video encoder indicates, in a bitstream that includes a coded representation of video data, a reference picture that includes the reference block for the inter-predicted PU. A video decoder receives the bitstream, determines the reference pictures of the inter-predicted PUs of the tree block group, and generates decoded video blocks using the reference blocks of the inter-predicted PUs. | 05-16-2013 |
20130128964 | REFERENCE MODE SELECTION IN INTRA MODE CODING - A video coder can determine a first most probable intra prediction mode and a second most probable intra prediction mode for a current video block, and based on the first and second most probable intra prediction modes, determine an estimate of an actual intra prediction mode used to code the current video block. The estimate of the actual intra prediction mode can be determined by selecting one of the first most probable mode and the second most probable mode as the estimate of the actual intra prediction in response to both the first most probable mode and the second most probable mode being different angular prediction modes. The estimate of the actual intra prediction mode plus difference information can be used to identify the actual intra prediction mode used to code the current video block. | 05-23-2013 |
20130163668 | PERFORMING MOTION VECTOR PREDICTION FOR VIDEO CODING - In general, techniques are described for performing motion vector prediction for video coding. A video coding device comprising a processor may perform the techniques. The processor may be configured to determine a plurality of candidate motion vectors for a current block of the video data so as to perform the motion vector prediction process and scale one or more of the plurality of candidate motion vectors determined for the current block of the video data to generate one or more scaled candidate motion vectors. The processor may then be configured to modify the scaled candidate motion vectors to be within a specified range. | 06-27-2013 |
20130182774 | INDICATION OF USE OF WAVEFRONT PARALLEL PROCESSING IN VIDEO CODING - A video encoder generates a bitstream that includes a syntax element that indicates whether a picture is encoded according either a first coding mode or a second coding mode. In the first coding mode, the picture is entirely encoded using wavefront parallel processing (WPP). In the second coding mode, each tile of the picture is encoded without using WPP and the picture may have one or more tiles. A video decoder may parse the syntax element from the bitstream. In response to determining that the syntax element has a particular value, the video decoder decodes the picture entirely using WPP. In response to determining that the syntax element does not have the particular value, the video decoder decodes each tile of the picture without using WPP. | 07-18-2013 |
20130182775 | SUB-STREAMS FOR WAVEFRONT PARALLEL PROCESSING IN VIDEO CODING - A video encoder signals whether WPP is used to encode a picture of a sequence of video picture. If WPP is used to encode the picture, the video encoder generates a coded slice NAL unit that includes a plurality of sub-streams, each of which includes a consecutive series of bits that represents one encoded row of coding tree blocks (CTBs) in a slice of the picture. A video decoder receives a bitstream that includes the coded slice NAL unit. Furthermore, the video decoder may determine, based on a syntax element in the bitstream, that the slice is encoded using WPP and may decode the slice using WPP. | 07-18-2013 |
20130188700 | CONTEXT ADAPTIVE ENTROPY CODING WITH A REDUCED INITIALIZATION VALUE SET - Techniques for coding data, such as, e.g., video data, include coding a first syntax element, conforming to a particular type of syntax element, of a first slice of video data, conforming to a first slice type, using an initialization value set. The techniques further include coding a second syntax element, conforming to the same type of syntax element, of a second slice of video data, conforming to a second slice type, using the same initialization value set. In this example, the first slice type may be different from the second slice type. Also in this example, at least one of the first slice type and the second slice type may be a temporally predicted slice type. For example, the at least one of the first and second slice types may be a unidirectional inter-prediction (P) slice type, or a bi-directional inter-prediction (B) slice type. | 07-25-2013 |
20130202038 | RESTRICTION OF PREDICTION UNITS IN B SLICES TO UNI-DIRECTIONAL INTER PREDICTION - A video coding device generates a motion vector (MV) candidate list for a prediction unit (PU) of a coding unit (CU) that is partitioned into four equally-sized PUs. The video coding device converts a bi-directional MV candidate in the MV candidate list into a uni-directional MV candidate. In addition, the video coding device determines a selected MV candidate in the merge candidate list and generates a predictive video block for the PU based at least in part on one or more reference blocks indicated by motion information specified by the selected MV candidate. | 08-08-2013 |
20130259130 | WEIGHTED PREDICTION PARAMETER CODING - The techniques are generally related to the coding of weighted prediction parameters. A video coder may determine the weighted prediction parameters for a reference picture list based on coded weighted prediction parameters for another reference picture list. Examples of the reference picture list include reference picture lists constructed for coding purposes, including a combined reference picture list. | 10-03-2013 |
20130272370 | WAVEFRONT PARALLEL PROCESSING FOR VIDEO CODING - In one example, a video coder may be configured to determine that a slice of a picture of video data begins in a row of coding tree units (CTUs) in the picture at a position other than a beginning of the row. Based on the determination, the video coder may be further configured to determine that the slice ends within the row of CTUs. The video coder may be further configured to code the slice based on the determination that the slice ends within the row of CTUs. | 10-17-2013 |
20130272377 | BYPASS BINS FOR REFERENCE INDEX CODING IN VIDEO CODING - In an example, aspects of this disclosure relate to a method for decoding a reference index syntax element in a video decoding process that includes decoding at least one bin of a reference index value with a context coding mode of a context-adaptive binary arithmetic coding (CABAC) process. The method also includes decoding, when the reference index value comprises more bins than the at least one bin coded with the context coded mode, at least another bin of the reference index value with a bypass coding mode of the CABAC process, and binarizing the reference index value. | 10-17-2013 |
20130272380 | GROUPING BYPASS CODED SYNTAX ELEMENTS IN VIDEO CODING - A video encoding device is configured to generate a first group of syntax elements. Each syntax element in the first group indicates whether a prediction mode of a respective prediction unit (PU) is based on an index into a list of most probable modes. A second group of syntax elements is generated that correspond to respective syntax elements in the first group. The syntax elements in the second group identify either an index into the list of most probable modes or an intra-prediction mode. The first group of syntax elements are context adaptive binary arithmetic coding (CABAC) encoded, and the second group of syntax elements are bypass encoded. A video decoder is configured to receive the entropy encoded first and second groups of syntax elements. The video decoder CABAC decodes the first group of flags and bypass decodes the second group of flags. | 10-17-2013 |
20130272385 | LEVEL DECISION IN RATE DISTORTION OPTIMIZED QUANTIZATION - A computing device, such as a video encoder, determines an initial quantized level for a coefficient of a coefficient block and determines whether the coefficient is less than the product of the initial quantized level and a quantization step size value. In response to determining that the coefficient is less than the product of the initial quantized level and the quantization step size value, the computing device determines rate-distortion costs of quantizing the coefficient to be the initial quantized level for the coefficient, the initial quantized level minus one, and in some circumstances, 0. The computing device determines an actual quantized level for the coefficient based at least in part on the calculated rate-distortion costs and includes the actual quantized level in a quantized version of the coefficient block. | 10-17-2013 |
20130272386 | LOOKUP TABLE FOR RATE DISTORTION OPTIMIZED QUANTIZATION - A computing device, such as a video encoder, uses respective positions of respective coefficients in a coefficient block to look up, in a lookup table, respective quantization offsets for the respective coefficients. Furthermore, the computing device determines, based at least in part on the quantization offsets for the one or more coefficients, respective quantized levels for the respective coefficients. | 10-17-2013 |
20130272409 | BANDWIDTH REDUCTION IN VIDEO CODING THROUGH APPLYING THE SAME REFERENCE INDEX - Techniques for encoding and decoding video data are described. A method of coding video may include determining a plurality of motion vector candidates for a block of video data for use in a motion vector prediction process, wherein each of the motion vector candidates points to a respective reference frame index, performing the motion vector prediction process using the motion vector candidates to determine a motion vector for the block of video data, and performing motion compensation for the block of video data using the motion vector and a common reference frame index, wherein the common reference frame index is used regardless of the respective reference frame index associated with the determined motion vector. | 10-17-2013 |
20140003531 | TILES AND WAVEFRONT PARALLEL PROCESSING | 01-02-2014 |
20140003532 | WAVEFRONT PARALLEL PROCESSING FOR VIDEO CODING | 01-02-2014 |
20140341274 | CODING THE POSITION OF A LAST SIGNIFICANT COEFFICIENT WITHIN A VIDEO BLOCK BASED ON A SCANNING ORDER FOR THE BLOCK IN VIDEO CODING - In one example, an apparatus is disclosed for coding coefficients associated with a block of video data during a video coding process, wherein the apparatus includes a video coder configured to code x- and y-coordinates that indicate a position of a last non-zero coefficient within the block according to a scanning order associated with the block when the scanning order comprises a first scanning order, and code interchanged x- and y-coordinates that indicate the position of the last non-zero coefficient within the block according to the scanning order when the scanning order comprises a second scanning order, wherein the second scanning order is different than the first scanning order. | 11-20-2014 |
20140355616 | SINGLE NETWORK ABSTRACTION LAYER UNIT PACKETS WITH DECODING ORDER NUMBER FOR VIDEO CODING - A method for processing video data in a real-time transport protocol (RTP) payload includes encapsulating video data in a single network abstraction layer (NAL) unit packet for an RTP session. The single NAL unit packet contains a single NAL unit. The method may also include encapsulating decoding order number information in the single NAL unit packet based on at least one of: the RTP session being in a multi-stream transmission (MST) mode, or a maximum number of NAL units that may precede the NAL unit in a de-packetization buffer in reception order and follow the NAL unit in decoding order being greater than 0. | 12-04-2014 |