摘要:
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.
摘要:
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.
摘要:
This disclosure describes intra-smoothing techniques for intra-coding of video data. In one example, a video encoder is configured to determine a plurality of prediction samples for intra-predictive coding of a block to be coded in a video frame, calculate a local statistic for a first prediction sample of the prediction samples, select a filter from a plurality of filters based on the local statistic, and apply the selected filter to the first prediction sample. The video encoder may also be configured to calculate at least one local statistic for each prediction sample of the prediction samples, select a filter from a plurality of different filters based on the at least one local statistic for each prediction sample, and apply each selected filter to the corresponding prediction sample to generate the filtered version of the prediction sample. Embodiments further include video decoders and method of decoding encoded video signals.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.