Patent application number | Description | Published |
20080310504 | ADAPTIVE COEFFICIENT SCANNING FOR VIDEO CODING - This disclosure describes techniques for scanning coefficients of video blocks. In particular, the techniques of this disclosure adapt a scan order used to scan a two-dimensional block of coefficients into a one-dimensional coefficient vector based on statistics associated with one or more previously coded blocks. For example, statistics that indicate the likelihood that a given coefficient value in each position of a two-dimensional block is zero or non-zero may be collected for one or more previously coded blocks. At some point, an adjustment to the scan order can be made in order to better ensure that non-zero coefficients are grouped together near the front of the one-dimensional coefficient vector, which can improve the effectiveness of entropy coding. The collection of statistics and adjustment of scan order may be made separately for each possible prediction mode. | 12-18-2008 |
20080310507 | ADAPTIVE CODING OF VIDEO BLOCK PREDICTION MODE - This disclosure describes techniques for coding of header information of video blocks. In particular, the techniques of this disclosure select one of a plurality of prediction modes for use in generating a prediction block of a video block of a coding unit, the plurality of prediction modes including unidirectional prediction modes and multi-directional prediction modes that combine at least two unidirectional prediction modes. An encoding device encodes the prediction mode of the current video block based on prediction modes of one or more previously encoded video blocks of the coding unit. Likewise, a decoding unit receives encoded video data of a video block of a coding unit and decodes the encoded video data to identify one of a plurality of prediction modes for use in generating a prediction block of the video block based on prediction modes of one or more previously decoded video blocks of the coding unit. | 12-18-2008 |
20080310512 | SEPARABLE DIRECTIONAL TRANSFORMS - This disclosure describes techniques for transforming residual blocks of video data. In particular, a plurality of different transforms selectively applied to the residual blocks based on the prediction mode of the video blocks. At least a portion of the plurality of transforms are separable directional transform specifically trained for a corresponding prediction mode to provide better energy compaction for the residual blocks of the given prediction mode. Using separable directional transforms offers the benefits of lower computation complexity and storage requirement than use of non-separable directional transforms. Additionally, a scan order used to scan the coefficients of the residual block may be adjusted when applying separable directional transforms. In particular, the scan order may be adjusted based on statistics associated with one or more previously coded blocks to better ensure that non-zero coefficients are grouped near the front of the one-dimensional coefficient vector to improve the effectiveness of entropy coding. | 12-18-2008 |
20080310745 | ADAPTIVE COEFFICIENT SCANNING IN VIDEO CODING - This disclosure describes techniques for scanning coefficients of video blocks, e.g., quantized and transformed coefficients. Rather than use conventional zig-zag scanning, the techniques of this disclosure adapt the scanning order based on statistics associated with previously coded blocks that were coded in the same prediction mode. For each prediction mode, statistics of the coefficients are stored, e.g., indicating probabilities that given coefficients are zero or non-zero. Periodically, adjustments to the scanning order can be made in order to better ensure that non-zero coefficients are grouped together and zero value coefficients are grouped together, which can improve the effectiveness of entropy coding. The techniques of this disclosure provide thresholds and threshold adjustments that can reduce the frequency that the scanning order adjustments occur, yet still achieve desired improvements in compression due to such scanning order adjustments. | 12-18-2008 |
20090097548 | ENHANCEMENT LAYER CODING FOR SCALABLE VIDEO CODING - This disclosure describes scalable video coding techniques. In particular, the techniques may be used to encode refinements of a video block for enhancement layer bit streams in a single coding pass, thereby reducing coding complexity, coding delay and memory requirements. In some instances, the techniques encode each nonzero coefficient of a coefficient vector of the enhancement layer without knowledge of any subsequent coefficients. Coding the enhancement layer in a single pass may eliminate the need to perform a first pass to analyze the coefficient vector and a second pass for coding the coefficient vector based on the analysis. | 04-16-2009 |
20090097558 | SCALABLE VIDEO CODING TECHNIQUES FOR SCALABLE BITDEPTHS - This disclosure describes video coding techniques that are executed in a bitdepth-based scalable video coding (SVC) scheme. Base layer video data and enhancement layer video data may be defined at different bitdepths. The techniques of this disclosure concern the coding of enhancement layer video blocks using a unique combination of inter-layer predictive coding modes after determining that inter-layer prediction should be used. In particular, two or more different inter-layer predictive coding modes may be utilized block corresponding to inter base layer blocks, and one of these inter-layer predictive coding modes may also be utilized for blocks corresponding to intra base layer blocks. Syntax information can be generated at the encoder and communicated with the bitstream, so that a decoder can use the proper inter-layer predictive coding mode in the decoding. | 04-16-2009 |
20090097568 | ENTROPY CODING OF INTERLEAVED SUB-BLOCKS OF A VIDEO BLOCK - This disclosure describes techniques for entropy coding of video blocks, and proposes a syntax element that may promote coding efficiency. The syntax element may identify a number of non-zero value sub-blocks within a video block, wherein the non-zero value sub-blocks comprise sub-blocks within the video block that include at least one non-zero coefficient. A method of coding a video block may comprise coding the syntax element, generating the non-zero value sub-blocks of the video block, and entropy coding the non-zero value sub-blocks. | 04-16-2009 |
20090175331 | TWO PASS QUANTIZATION FOR CABAC CODERS - This disclosure describes techniques for quantizing coefficients of a video block for a video coding process that supports context-based adaptive binary arithmetic coding (CABAC). A method may comprise estimating a last non-zero coefficient of the video block, and generating a set of quantized coefficients for the video block based on an assumption that the estimated last non-zero coefficient is actually the last non-zero coefficient of the video block. | 07-09-2009 |
20090175332 | QUANTIZATION BASED ON RATE-DISTORTION MODELING FOR CABAC CODERS - This disclosure describes techniques for quantizing coefficients of a video block for a video coding process that supports context-based adaptive binary arithmetic coding (CABAC). A method may comprise generating a plurality of sets of quantized coefficients for the video block, wherein each of the sets of quantized coefficients is defined based on an assumption that a particular one of the coefficients of the video block corresponds to a last non-zero coefficient of the video block, estimating a plurality of costs associated with coding the video block via the CABAC, wherein the estimated costs are based respectively on different ones of the sets of quantized coefficients, and selecting a given one of the sets of quantized coefficients associated with a lowest cost. | 07-09-2009 |
20090175334 | ADAPTIVE CODING OF VIDEO BLOCK HEADER INFORMATION - This disclosure describes techniques for adaptively coding video block header information based on previously encoded video blocks. A video encoder may adaptively select a coding table for use in encoding a syntax element of a current video block based on corresponding syntax elements of one or more previously encoded blocks. In one aspect, the video encoder may adaptively select the coding table for use in encoding a block type of the current block based on block types of one or more video blocks adjacent to the current video block, i.e., neighboring video blocks. The video encoder may also predict one or more other header syntax elements of the current block based on at least one of the previously encoded video blocks. If prediction is successful, the video encoder may encode a flag to indicate the success of prediction. | 07-09-2009 |
20090175336 | VIDEO CODING OF FILTER COEFFICIENTS BASED ON HORIZONTAL AND VERTICAL SYMMETRY - This disclosure recognizes and exploits the fact that some of the filter coefficients defined at the encoder may possess symmetry relative to other filter coefficients. Accordingly, this disclosure describes techniques in which a first set of the filter coefficients are used to predictively encode a second set of the filter coefficients, thereby exploiting any symmetry between filter coefficients. Rather than communicate all of the filter coefficients to the decoding device, the encoding device may communicate the first set of filter coefficients and difference values associated with the second set of filter coefficients. Using this information, the decoder may be able to reconstruct all of the filter coefficients. In some cases, if exact symmetry is imposed, the need to send the difference values may be eliminated and the decoder may be able to derive the second set of filter coefficients from the first set of filter coefficients. | 07-09-2009 |
20090175349 | LAYERED ENCODED BITSTREAM STRUCTURE - This disclosure describes techniques for generating a layered encoded bitstream structure that exploits correlation in header information among video blocks of a coded unit of video data. A video encoder configured to operate in accordance with the techniques of this disclosure separates header information of the video blocks of a slice (or other coded unit) from the residual information of the video blocks of the slice. The video encoder run-length encodes the header information of the video blocks to better exploit the correlation of the header information among the blocks of the slice. After encoding the header information of the blocks of the slice, the video encoder encodes the residual information for each of the blocks of the slice. The video encoder transmits the encoded header information as a first sequence of bits and transmits the encoded residual information as second sequence of bits. | 07-09-2009 |
20090213930 | FAST MACROBLOCK DELTA QP DECISION - A system and method for encoding multimedia video is described. As video is encoded a quantization parameter is selected for each macroblock. As described herein, the quantization parameter for each macroblock may be selected by limiting the universe of all possible quantization parameters to a particular range of possible quantization parameter values. This increases the speed of video encoding by reducing the number of quantization parameters that are tested for each video macroblock. | 08-27-2009 |
20090257489 | RATE-DISTORTION QUANTIZATION FOR CONTEXT-ADAPTIVE VARIABLE LENGTH CODING (CAVLC) - In general, this disclosure provides techniques for quantization of the coefficients of video blocks in a manner that can achieve a desirable balance of rate and distortion. The described techniques may analyze a plurality of quantization levels associated with each individual coefficient to select the quantization level for the individual coefficients that results in a lowest coding cost. Since CAVLC does not encode each coefficient independently, the techniques may compute the coding costs for each of the candidate quantization levels associated with the individual coefficients based on quantization levels selected for previously quantized coefficients and estimated (or predicted) quantization levels for subsequent coefficients of a coefficient vector. The quantization levels for each of the coefficients are selected based on computed coding costs to obtain a set of quantized coefficients that minimize a rate-distortion model. | 10-15-2009 |
20090257493 | INTERPOLATION FILTER SUPPORT FOR SUB-PIXEL RESOLUTION IN VIDEO CODING - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
20090257494 | SYMMETRY FOR INTEROPLATION FILTERING OF SUB-PIXEL POSITIONS IN VIDEO CODING - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
20090257499 | ADVANCED INTERPOLATION TECHNIQUES FOR MOTION COMPENSATION IN VIDEO CODING - This disclosure describes various interpolation techniques performed by an encoder and a decoder during the motion compensation process of video coding. In one example, an encoder interpolates pixel values of reference video data based on a plurality of different pre-defined interpolation filters. In this example, the decoder receives a syntax element that identifies an interpolation filter, and interpolates pixel values of reference video data based on the interpolation filter identified by the syntax element. In another example, a method of interpolating predictive video data includes generating half-pixel values based on integer pixel values, rounding the half-pixel values to generate half-pixel interpolated values, storing the half-pixel values as non-rounded versions of the half-pixel values, and generating quarter-pixel values based on the non-rounded versions of the half-pixel values and the integer pixel values. | 10-15-2009 |
20090257500 | OFFSETS AT SUB-PIXEL RESOLUTION - This disclosure describes techniques applied during video encoding and decoding processes. In one example, a method of encoding video data comprises calculating a plurality of offset values for a coded unit of the video data, wherein the offset values are associated with a plurality of different integer and sub-integer pixel locations, applying the offset values to predictive video blocks to generate offset predictive video blocks, and encoding video blocks of the coded unit based on the offset predictive video blocks. In another example, a method of decoding video data comprises receiving a plurality of offset values for a coded unit of the video data, wherein the offset values are associated with a plurality of different integer and sub-integer pixel locations, applying the offset values to predictive video blocks to generate offset predictive video blocks, and decoding video blocks of the coded unit based on the offset predictive video blocks. | 10-15-2009 |
20090257501 | INTERPOLATION-LIKE FILTERING OF INTEGER-PIXEL POSITIONS IN VIDEO CODING - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
20090257502 | RATE-DISTORTION DEFINED INTERPOLATION FOR VIDEO CODING BASED ON FIXED FILTER OR ADAPTIVE FILTER - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
20090257503 | ADVANCED INTERPOLATION TECHNIQUES FOR MOTION COMPENSATION IN VIDEO CODING - This disclosure describes various interpolation techniques performed by an encoder and a decoder during the motion compensation process of video coding. In one example, an encoder interpolates pixel values of reference video data based on a plurality of different pre-defined interpolation filters. In this example, the decoder receives a syntax element that identifies an interpolation filter, and interpolates pixel values of reference video data based on the interpolation filter identified by the syntax element. In another example, a method of interpolating predictive video data includes generating half-pixel values based on integer pixel values, rounding the half-pixel values to generate half-pixel interpolated values, storing the half-pixel values as non-rounded versions of the half-pixel values, and generating quarter-pixel values based on the non-rounded versions of the half-pixel values and the integer pixel values. | 10-15-2009 |
20090257668 | PREDICTION TECHNIQUES FOR INTERPOLATION IN VIDEO CODING - This disclosure describes filtering techniques applied by an encoder and a decoder during the prediction stage of a video encoding and/or decoding process. The filtering techniques may enhance the accuracy of predictive data used during fractional interpolation, and may improve predictive data of integer blocks of pixels. There are several aspects to this disclosure, including a useful twelve-pixel filter support that may be used for interpolation, techniques that use coefficient symmetry and pixel symmetry to reduce the amount of data needed to be sent between an encoder and a decoder to configure the filter support for interpolation, and techniques for filtering data at integer pixel locations in a manner that is similar to sub-pixel interpolation. Other aspects of this disclosure concern techniques for encoding information in the bitstream to convey the type of filter used, and possibly the filter coefficients used. Predictive coding of filter coefficients is also described. | 10-15-2009 |
20100002770 | VIDEO ENCODING BY FILTER SELECTION - A method and a device are described for selecting between multiple available filters in an encoder to provide a frame having a low error and distortion rate. For each full and sub pixel position, determining whether to use an alternative filter over the default filter during interpolation by estimating the rate distortion gain of using each filter and signaling to the decoder the optimal filter(s) applied to each full and sub-pixel position. In one embodiment, identifying a reference frame and a current frame, interpolating the reference frame using a default filter to create a default interpolated frame, interpolating the reference frame using an alternative filter to create an alternative interpolated frame, determining for each sub-pixel position whether to use the default filter or the alternative filter based on a minimal cost to generate a final reference frame. | 01-07-2010 |
20100074332 | OFFSET CALCULATION IN SWITCHED INTERPOLATION FILTERS - This disclosure describes techniques for adding offset to predictive video blocks during video coding. In one example, a method of encoding a video block includes interpolating a first block of predictive values based on a first reference video unit within a first list of reference data, and a second block of predictive values based on a second reference video unit within a second list of reference data, calculating, for sub-integer pixel positions, a first offset value based on the first block and the current video block, and a second offset value based on the first offset value and the second block, determining a final block of offset values based on the first block of predictive values, the second block of predictive values, the first offset values, and the second offset values, and encoding the current video block based on the final block of offset values. | 03-25-2010 |
20100086029 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels, for example, 64×64 pixels. In one example, an apparatus includes a video encoder configured to encode a video block having a size of more than 16×16 pixels, generate block-type syntax information that indicates the size of the block, and generate a coded block pattern value for the encoded block, wherein the coded block pattern value indicates whether the encoded block includes at least one non-zero coefficient. The encoder may set the coded block pattern value to zero when the encoded block does not include at least one non-zero coefficient or set the coded block pattern value to one when the encoded block includes a non-zero coefficient. | 04-08-2010 |
20100086030 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels, for example, 64×64 pixels. Each macroblock may be partitioned into two or more partitions, and two or more of the partitions may be encoded using different modes. In one example, an apparatus includes a video encoder configured to receive a video block having a size of more than 16×16 pixels, partition the block into partitions, encode one of the partitions using a first encoding mode, encode another of the partitions using a second encoding mode different from the first encoding mode, and generate block-type syntax information that indicates the size of the block and identifies the partitions and the encoding modes used to encode the partitions. | 04-08-2010 |
20100086031 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels, for example, 64×64 pixels. In one example, an apparatus includes a video encoder configured to receive a video coding unit, determine a first rate-distortion metric for encoding the video coding unit using first video blocks with sizes of 16×16 pixels, determine a second rate-distortion metric for encoding the video coding unit using second video blocks with sizes of more than 16×16 pixels, encode the video coding unit using the first video blocks when the first rate-distortion metric is less than second rate-distortion metric, and encode the video coding unit using the second video blocks when the second rate-distortion metric is less than the first rate-distortion metric. | 04-08-2010 |
20100086032 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels. In one example, an apparatus includes a video encoder configured to encode a coded unit comprising a plurality of video blocks, wherein at least one of the plurality of video blocks comprises a size of more than 16×16 pixels and to generate syntax information for the coded unit that includes a maximum size value, wherein the maximum size value indicates a size of a largest one of the plurality of video blocks in the coded unit. The syntax information may also include a minimum size value. In this manner, the encoder may indicate to a decoder the proper syntax decoder to apply to the coded unit. | 04-08-2010 |
20100086049 | VIDEO CODING USING TRANSFORMS BIGGER THAN 4X4 AND 8X8 - In a video processing system, a method and system for applying transforms larger than 8×8 and non-rectangular transforms, and generating transform size syntax elements indicative of the transforms for video decoding are provided. The transform size syntax element may be generated by an encoder based on a prediction block size of a video block and the contents of the video block. Further, the transform size syntax element may be generated according to a set of rules to select from 4×4, 8×8, and larger transform sizes during an encoding process. A decoder may perform an inverse transform based on the transform size syntax element and the rules used by the encoder. The transform size syntax element may be transmitted to the decoder as part of the encoded video bitstream. | 04-08-2010 |
20100111182 | DIGITAL VIDEO CODING WITH INTERPOLATION FILTERS AND OFFSETS - This disclosure describes techniques for encoding digital video data using interpolation filters and offsets. An encoder may be configured to select interpolation filters for sub-pixel precision motion estimation based on historical interpolation results obtained for previously encoded video units, such as frames or slices. The encoder also may be configured to compute and assign offsets to the sub-pixel positions after interpolation based on differences between a reference unit and the unit to be coded. The computation and assignment of offsets may be performed before motion estimation. Motion estimation may be refined so that the motion search considers sub-pixel positions to which offsets have been previously added and evaluates sub-pixel positions that have a non-zero offset. In some cases, interpolation filter selection, offset computation, and/or refined motion estimation for a given unit may be performed in a single encoding pass. | 05-06-2010 |
20100118970 | TEMPORAL ERROR CONCEALMENT FOR VIDEO COMMUNICATIONS - Methods and systems for processing video data are described. A set of candidate motion vectors is selected from motion vectors associated with macroblocks in a first frame of video data and from motion vectors associated with macroblocks in a second frame of the video data. A statistical measure of the set is determined. The statistical measure defines a motion vector for a macroblock of interest in the second frame. | 05-13-2010 |
20100158103 | COMBINED SCHEME FOR INTERPOLATION FILTERING, IN-LOOP FILTERING AND POST-LOOP FILTERING IN VIDEO CODING - In one example, this disclosure describes filtering techniques for filtering of video blocks of a video unit. The filtering techniques may select one or more different types of filtering for each video block of the video unit based on various factors such as whether the video block is inter-coded or intra-coded, and whether adaptive interpolations were preformed during a motion compensation process during the encoding of the video block. When adaptive interpolations were performed, the adaptive interpolations may provide a level of filtering that renders additional filtering unnecessary or undesirable in some cases. | 06-24-2010 |
20100177822 | FILTER PREDICTION BASED ON ACTIVITY METRICS IN VIDEO CODING - This disclosure describes techniques associated with filtering of video data in a video encoding and/or decoding process. In accordance with this disclosure, filtering is applied at an encoder, and filter information is encoded in the bitstream to identify the filtering that was applied at the encoder. Different types of filtering may be applied based on an activity metric determined for the video data. Moreover, in accordance with this disclosure, the manner in which the filter information is encoded into the bitstream may be dependent on the activity metric. In particular, for a first range of the activity metric, one or more filters are encoded directly, and for a second range of the activity metric, one or more filters are predictively encoded. | 07-15-2010 |
20100284460 | VIDEO ENCODING WITH TEMPORALLY CONSTRAINED SPATIAL DEPENDENCY FOR LOCALIZED DECODING - This disclosure describes techniques for region-of-interest (ROI) encoding. In accordance with the techniques described herein, an encoding device may determine a temporal spatial dependency value for a candidate reference video block for inter-coding a current block in a video frame. The encoding device may compare the temporal spatial dependency value to a threshold value and select a coding mode for the current block based on the comparison. A decoding device may receive data defining a ROI as well as the temporal spatial dependency value and decode a video block in the ROI based at least in part on the temporal spatial dependency value. In this manner, the techniques of this disclosure may allow a video content viewer the ability to choose a ROI to watch. | 11-11-2010 |
20100284462 | METHODS AND SYSTEMS FOR SIGNIFICANCE COEFFICIENT CODING IN VIDEO COMPRESSION - A method for decoding significance coefficients in an encoded video sequence is described. An encoded video bitstream is received. Codebook table information is retrieved from the bitstream. Significance symbols are decoded using the retrieved codebook table information. Significance coefficients are decoded using the significance symbols. A plurality of transform coefficients is dequantized. An inverse transform is applied to a residual signal. A video sequence is constructed. A method for coding significance coefficients in a video sequence is also described. | 11-11-2010 |
20100284471 | VIDEO DECODING USING TEMPORALLY CONSTRAINED SPATIAL DEPENDENCY - This disclosure describes techniques for region-of-interest (ROI) encoding. In accordance with the techniques described herein, an encoding device may determine a temporal spatial dependency value for a candidate reference video block for inter-coding a current block in a video frame. The encoding device may compare the temporal spatial dependency value to a threshold value and select a coding mode for the current block based on the comparison. A decoding device may receive data defining a ROI as well as the temporal spatial dependency value and decode a video block in the ROI based at least in part on the temporal spatial dependency value. In this manner, the techniques of this disclosure may allow a video content viewer the ability to choose a ROI to watch. | 11-11-2010 |
20110007799 | NON-ZERO ROUNDING AND PREDICTION MODE SELECTION TECHNIQUES IN VIDEO ENCODING - In one aspect of this disclosure, techniques are described for selecting among default weighted prediction, implicit weighted prediction, and explicit weighted prediction. In this context, techniques are also described for adding offset to prediction data, e.g., using the format of explicit weighted prediction to allow for offsets to predictive data that is otherwise determined by implicit or default weighted prediction. | 01-13-2011 |
20110007802 | NON-ZERO ROUNDING AND PREDICTION MODE SELECTION TECHNIQUES IN VIDEO ENCODING - In one aspect of this disclosure, rounding adjustments to bi-directional predictive data may be purposely eliminated to provide predictive data that lacks any rounding bias. In this case, rounded and unrounded predictive data may both be considered in a rate-distortion analysis to identify the best data for prediction of a given video block. In another aspect of this disclosure, techniques are described for selecting among default weighted prediction, implicit weighted prediction, and explicit weighted prediction. In this context, techniques are also described for adding offset to prediction data, e.g., using the format of explicit weighted prediction to allow for offsets to predictive data that is otherwise determined by implicit or default weighted prediction. | 01-13-2011 |
20110110427 | Selective deblock filtering techniques for video coding - This disclosure describes selective deblock filtering techniques that are particularly useful with coding standards that do not specify in-loop deblock filtering for standard compliance. In accordance with this disclosure, deblock filtering may be selectively performed with respect to block boundaries of a given video block being coded, a motion compensation process can be performed using a filtered version of the prediction video frame used to code the given video block, or both. This disclosure also provides selection rules that can be applied to determine what type of deblocking techniques to apply in various scenarios. The selection rules may improve the video coding and may also ensure that mismatch between video blocks at an encoder and a decoder is not introduced by the deblock filtering. | 05-12-2011 |
20120027079 | Adaptive Interpolation Filters for Multi-Layered Video Delivery - Adaptive interpolation filters for multi-layered video delivery are described. Combinations of such adaptive filters with other pre-processing steps in the context of frame or 2D compatible 3D and 2D scalable video delivery system are also addressed. | 02-02-2012 |
20120177109 | Speedup Techniques for Rate Distortion Optimized Quantization - Techniques for selecting a coding mode for an image coding process are described. Coding modes can be selected through a coding mode transition state machine, a re-quantization process, selection of an optimal transform size, by skipping some quantization parameters, or by performing motion search. | 07-12-2012 |
20120201301 | VIDEO CODING WITH FINE GRANULARITY SPATIAL SCALABILITY - The disclosure is directed to video coding techniques that support spatial scalability using a generalized fine granularity scalability (FGS) approach. Various degrees of spatial scalability can be achieved by sending spatially scalable enhancement layers in a generalized FGS format. Spatially scalable enhancement bitstreams can be arbitrarily truncated to conform to network conditions, channel conditions and/or decoder capabilities. Coding coefficients and syntax elements for spatial scalability can be embedded in a generalized FGS format. For good network or channel conditions, and/or enhanced decoder capabilities, additional bits received via one or more enhancement layers permit encoded video to be reconstructed with increased spatial resolution and continuously improved video quality across different spatial resolutions. The techniques permit spatial scalability layers to be coded as FGS layers, rather than discrete layers, permitting arbitrary scalability. The techniques may include features to curb error propagation that may otherwise arise due to partial decoding. | 08-09-2012 |
20130039430 | Guided Image Up-Sampling in Video Coding - An encoder receives a first image of a first spatial resolution and a second image of a second spatial resolution, wherein both the first image and the second image represent the same scene and the second spatial resolution is higher than the first spatial resolution. A filter is selected to up-sample the first image to a third image with a spatial resolution same as the second spatial resolution. The filtering coefficients for the up-sampling filter are computed by minimizing an error measurement (e.g., MSE) between pixel values of the second image and the third image. The computed set of filtering coefficients is signaled to a receiver (e.g., as metadata). A decoder receives the first image (or its approximation) and the metadata, and may up-sample the first image using the same filter and optimally selected filtering coefficients as those derived by the encoder. | 02-14-2013 |
20130044812 | ADAPTIVE CODING OF VIDEO BLOCK PREDICTION MODE - This disclosure describes techniques for coding of header information of video blocks. In particular, the techniques of this disclosure select one of a plurality of prediction modes for use in generating a prediction block of a video block of a coding unit, the plurality of prediction modes including unidirectional prediction modes and multi-directional prediction modes that combine at least two unidirectional prediction modes. An encoding device encodes the prediction mode of the current video block based on prediction modes of one or more previously encoded video blocks of the coding unit. Likewise, a decoding unit receives encoded video data of a video block of a coding unit and decodes the encoded video data to identify one of a plurality of prediction modes for use in generating a prediction block of the video block based on prediction modes of one or more previously decoded video blocks of the coding unit. | 02-21-2013 |
20130114732 | VIDEO AND DATA PROCESSING USING EVEN-ODD INTEGER TRANSFORMS - Methods, apparatuses and systems for integer transforms, and/or integer transform operations, for transforming data (e.g., residual video data) are disclosed. Included among such methods, apparatuses and systems is an apparatus that may include a processor and memory. The memory may include a set of transform matrices and instructions executable by the processor for transforming data (e.g., residual video data) using any of the set of transform matrices. Each transform matrix of the set of transform matrices may be orthogonal or, alternatively, may be approximately orthogonal and be fully factorizable. Each transform matrix of the set of transform matrices may have a different number of elements. Each element of the respective number of elements is an integer. Differences among norms of basis vectors of each transform matrix satisfy a given threshold, and the basis vectors approximate corresponding basis vectors of a discrete cosine transform (DCT) matrix. | 05-09-2013 |
20130121416 | Reference Processing Using Advanced Motion Models for Video Coding - Processing a reference picture is described. A reference processing unit enables signaling of parameters such as motion model parameters, interpolation filter parameters, intensity compensation parameters, and denoising filter parameters. Methods for estimating the various parameters are also discussed. Processing improves quality of a reference picture prior to its use for prediction of a subsequent picture and thus improves the prediction. | 05-16-2013 |
20130142262 | Buffered Adaptive Filters - A buffer is established in a video encoder and/or a video decoder. An adaptive filter is buffered in the established buffer. An input video signal is coded using the buffered filter. The filter buffer may be managed, e.g., as to buffer size or capacity, filter placement within the buffer, and buffered default filters. Adaptive filters may be signaled and buffered for multiple reference pictures. | 06-06-2013 |
20130177066 | Context based Inverse Mapping Method for Layered Codec - Context based inverse mapping methods are provided. An image with pixel values within a lower dynamic range can be mapped to an image with pixel values within a higher dynamic range by utilizing context information associated with pixels in the lower dynamic range image. | 07-11-2013 |
20130188697 | METHOD AND APPARATUS FOR SIGNALING AND CONSTRUCTION OF VIDEO CODING REFERENCE PICTURE LISTS - Improved method and apparatus for signaling of reference pictures used for temporal prediction. The signaling schemes and construction process for different reference picture lists in HEVC Working Draft 5 (WD5) are improved. | 07-25-2013 |
20130195204 | Methods and Systems for Video Delivery Supporting Adaptation to Viewing Conditions - Described herein are methods and systems associated with viewing condition adaption of multimedia content. A method for receiving multimedia content with a device from a network may include determining a viewing parameter, transmitting a request for the multimedia content to the network, whereby the request may be based on the viewing parameter, and receiving the multimedia content from the network, whereby the multimedia content may be processed at a rate according to the viewing parameter. The viewing parameter may include at least one of: a user viewing parameter, a device viewing parameter, or a content viewing parameter. The method may further include receiving a multimedia presentation description (MPD) file from the network. The MPD file may include information relating to the rate of the multimedia content and information relating to the rate may include a descriptor relating to the viewing parameter, whereby the descriptor may be required or optional. | 08-01-2013 |
20130208792 | REFERENCE PICTURE SET (RPS) SIGNALING FOR SCALABLE HIGH EFFICIENCY VIDEO CODING (HEVC) - Embodiments contemplate coding video data by generating a video encoded bitstream that may include reference picture set (RPS) extensions for inter-layer reference pictures, and the extensions may include inter-layer delta Picture Order Counts (POCs). Embodiments may also include signaling that lower layer reference pictures may be available in a lower layer decoder picture buffer (DPB), and/or an aggregate DPB, that may be added to the RPS set of a higher layer. The bitstream may include a signal indicating whether the higher layer RPS may be specified by a lower layer RPS, and the lower layer RPS may be temporal, inter-layer prediction (ILP), or both. | 08-15-2013 |
20130243091 | SYSTEMS AND METHODS FOR SPATIAL PREDICTION - Systems, methods, and instrumentalities are disclosed relating to intra prediction of a video signal based on mode-dependent subsampling. A block of coefficients associated with a first sub block of a video block, one or more blocks of coefficients associated with one or more remaining sub blocks of the video block, and an indication of a prediction mode for the video block may be received. One or more interpolating techniques, a predicted first sub block, and the predicted sub blocks of the one or more remaining sub blocks may be determined. A reconstructed first sub block and one or more reconstructed remaining sub blocks may be generated. A reconstructed video block may be formed based on the prediction mode, the reconstructed first sub block, and the one or more reconstructed remaining sub blocks. | 09-19-2013 |
20130308701 | VIDEO CODING WITH LARGE MACROBLOCKS - Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels. In one example, an apparatus includes a video encoder configured to encode a coded unit comprising a plurality of video blocks, wherein at least one of the plurality of video blocks comprises a size of more than 16×16 pixels and to generate syntax information for the coded unit that includes a maximum size value, wherein the maximum size value indicates a size of a largest one of the plurality of video blocks in the coded unit. The syntax information may also include a minimum size value. In this manner, the encoder may indicate to a decoder the proper syntax decoder to apply to the coded unit. | 11-21-2013 |
20140010282 | POWER AWARE VIDEO DECODING AND STREAMING - Methods and systems are disclosed for a mobile device to decode video based on available power and/or energy. For example, the mobile device may receive a media description file (MDF) from for a video stream from a video server. The MDF may include complexity information associated with a plurality of video segments. The complexity information may be related to the amount of processing power to be utilized for decoding the segment at the mobile device. The mobile device may determine at least one power metric for the mobile device. The mobile device may determine a first complexity level to be requested for a first video segment based on the complexity information from the MDF and the power metric. The mobile device may dynamically alter the decoding process to save energy based on the detected power/energy level. | 01-09-2014 |
20140010294 | CODEC ARCHITECTURE FOR MULTIPLE LAYER VIDEO CODING - Systems, methods, and instrumentalities are provided to implement video coding system (VCS). The VCS may be configured to receive a video signal, which may include one or more layers (e.g., a base layer (BL) and/or one or more enhancement layers (ELs)). The VCS may be configured to process a BL picture into an inter-layer reference (ILR) picture, e.g., using picture level inter-layer prediction process. The VCS may be configured to select one or both of the processed ILR picture or an enhancement layer (EL) reference picture. The selected reference picture(s) may comprise one of the EL reference picture, or the ILR picture. The VCS may be configured to predict a current EL picture using one or more of the selected ILR picture or the EL reference picture. The VCS may be configured to store the processed ILR picture in an EL decoded picture buffer (DPB). | 01-09-2014 |
20140036999 | FRAME PRIORITIZATION BASED ON PREDICTION INFORMATION - Priority information may be used to distinguish between different types of video data, such as different video packets or video frames. The different types of video data may be included in the same temporal level and/or different temporal levels in a hierarchical structure. A different priority level may be determined for different types of video data at the encoder and may be indicated to other processing modules at the encoder, or to the decoder, or other network entities such as a router or a gateway. The priority level may be indicated in a header of a video packet or signaling protocol. The priority level may be determined explicitly or implicitly. The priority level may be indicated relative to another priority or using a priority identifier that indicates the priority level. | 02-06-2014 |
20140037015 | SAMPLING GRID INFORMATION FOR SPATIAL LAYERS IN MULTI-LAYER VIDEO CODING - Sampling grid information may be determined for multi-layer video coding systems. The sampling grid information may be used to align the video layers of a coding system. Sampling grid correction may be performed based on the sampling grid information. The sampling grids may also be detected. In some embodiments, a sampling grid precision may also be detected and/or signaled. | 02-06-2014 |
20140050264 | Slice base skip mode signaling for multiple layer video coding - Methods and apparatus may be used to signal slice skip mode of a multiple layer scalable coding system. A correlation between the corresponding regions of video signals in multiple layers and inter-layer processing techniques may make it possible to infer a slice or picture in the enhancement layer from the corresponding region in a base layer picture. Accordingly, a video stream may be encoded to indicate that an enhancement layer slice or picture may be skipped. | 02-20-2014 |
20140064374 | METHOD AND APPARATUS OF MOTION VECTOR PREDICTION FOR SCALABLE VIDEO CODING - Inter-layer motion mapping information may be used to enable temporal motion vector prediction (TMVP) of an enhancement layer of a bitstream. For example, a reference picture and a motion vector (MV) of an inter-layer video block may be determined. The reference picture may be determined based on a collocated base layer video block. For example, the reference picture may be a collocated inter-layer reference picture of the reference picture of the collocated base layer video block. The MV may be determined based on a MV of the collocated base layer video block. For example, the MV may be determined by determining the MV of the collocated base layer video block and scaling the MV of the collocated base layer video block according to a spatial ratio between the base layer and the enhancement layer. TMVP may be performed on the enhancement layer picture using the MV of the inter-layer video block. | 03-06-2014 |
20140072031 | Reference Picture Lists Modification - Systems, methods, and instrumentalities are disclosed relating to modifications to reference picture lists used for multiple layer video coding. A bitstream that may include a reference picture list of a slice may be received. An indication to reposition a reference picture within the reference picture list from a first position to a second position may be received. An indication to insert a reference picture within the reference picture list at a position may be received. The reference picture may be repositioned and/or inserted in the reference picture list in response to receiving the indication. A reference picture previously associated with the position may be shifted in the reference picture list according to the indication to reposition and/or insert the reference picture, although an indication to reposition the reference picture previously associated with the position may not be received. The slice may be decoded using the reference picture list. | 03-13-2014 |
20140079126 | Method and Apparatus for Region of Interest Video Coding Using Tiles and Tile Groups - Systems, methods, and instrumentalities are disclosed relating to region of interest (ROI) video coding using tiles and tile groups. An encoded video sequence including a plurality of tiles may be received. The plurality of tiles may be divided into one or more tile groups. Signaling indicating parameters of the one or more tile groups may be received. A tile group of the one or more tiles groups may be decoded and a picture relating to the decoded tile group may be displayed. The decoded tile group may overlap the ROI. The ROI may correspond to the displayed picture and the displayed picture may be a portion of the encoded video sequence. The tile groups that do not overlap the ROI may not be decoded. | 03-20-2014 |
20140092999 | CROSS-PLANE FILTERING FOR CHROMA SIGNAL ENHANCEMENT IN VIDEO CODING - Cross-plane filtering may be used to restore blurred edges and/or textures in one or both chroma planes using information from a corresponding luma plane. Adaptive cross-plane filters may be implemented. Cross-plane filter coefficients may be quantized and/or signaled such that overhead in a bitstream minimizes performance degradation. Cross-plane filtering may be applied to select regions of a video image (e.g., to edge areas). Cross-plane filters may be implemented in single-layer video coding systems and/or multi-layer video coding systems. | 04-03-2014 |
20140112387 | SEPARABLE DIRECTIONAL TRANSFORMS - This disclosure describes techniques for transforming residual blocks of video data. In particular, a plurality of different transforms selectively applied to the residual blocks based on the prediction mode of the video blocks. At least a portion of the plurality of transforms are separable directional transform specifically trained for a corresponding prediction mode to provide better energy compaction for the residual blocks of the given prediction mode. Using separable directional transforms offers the benefits of lower computation complexity and storage requirement than use of non-separable directional transforms. Additionally, a scan order used to scan the coefficients of the residual block may be adjusted when applying separable directional transforms. In particular, the scan order may be adjusted based on statistics associated with one or more previously coded blocks to better ensure that non-zero coefficients are grouped near the front of the one-dimensional coefficient vector to improve the effectiveness of entropy coding. | 04-24-2014 |
20140321551 | WEIGHTED PREDICTIONS BASED ON MOTION INFORMATION - Weighted predictions may be used in a video encoder or decoder to improve the quality of motion predictions. Systems and methods of video processing with weighted predictions based on motion information are discussed. Specifically, systems and methods of video processing with iterated and refined weighted predictions based on motion information are shown. | 10-30-2014 |
20140341273 | Hybrid Reference Picture Reconstruction Method for Single and Multiple Layered Video Coding Systems - An inter-layer reference picture is generated either by considering an inverse mapped signal from a base layer, a temporal signal from an enhancement layer, or a combination of both. | 11-20-2014 |
20140341305 | SPECIFYING VISUAL DYNAMIC RANGE CODING OPERATIONS AND PARAMETERS - Coding syntaxes in compliance with same or different VDR specifications may be signaled by upstream coding devices such as VDR encoders to downstream coding devices such as VDR decoders in a common vehicle in the form of RPU data units. VDR coding operations and operational parameters may be specified as sequence level, frame level, or partition level syntax elements in a coding syntax. Syntax elements in a coding syntax may be coded directly in one or more current RPU data units under a current RPU ID, predicted from other partitions/segments/ranges previously sent with the same current RPU ID, or predicted from other frame level or sequence level syntax elements previously sent with a previous RPU ID. A downstream device may perform decoding operations on multi-layered input image data based on received coding syntaxes to construct VDR images. | 11-20-2014 |
20140348232 | Multiview and Bitdepth Scalable Video Delivery - A video encoding and decoding system for use in a multiview and bitdepth coding system is described. Such system can comprise a plurality of layer groupings, where each group can be adapted to encode and/or decode based on predictions from previous layers and a plurality of data categories from the input video data. | 11-27-2014 |