Abstract: Techniques are described for initializing a Rice parameter used to define codes for coefficient level coding. According to the techniques, the initial value of the Rice parameter is determined for a coefficient group (CG) in a transform block of video data based on statistics of coefficient levels that are gathered for previously coded coefficients of the video data. The statistics may be statistics of absolute values of coefficient levels or remaining absolute values of coefficient levels of previously coded coefficients. A value of the statistics may be initialized to zero at a beginning of a video slice and updated based on coefficient levels coded in each CG of the slice. The statistics may be updated once per CG. In some cases, statistics may be gathered separately for each of a plurality of different categories of CGs that are defined based on characteristics of transform blocks that include the CGs.

Abstract: Techniques coding video data, including a mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture, may include determining a predictive block of video data for the current block of video data, wherein the predictive block of video data is a reconstructed block of video data within the same picture as the current block of video data. A two-dimensional vector, which may be used by a video coder to identify the predictive block of video data, includes a horizontal displacement component and a vertical displacement component relative to the current block of video data. The mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture may be referred to as Intra Block Copy or Intra Motion Compensation.

Abstract: Provided are methods, apparatus, and computer-readable medium for processing video data using a video coding system that implements ST 2094-10 for modifying the color volume of a video signal. In various implementations, metadata blocks that include color volume transform parameters can be included in an encoded bitstream with an encoded video. Mastering display color volume parameters must also be included in the encoded bitstream when the color volume transform parameters are included in the bitstream. When the mastering display color volume parameters are not also included in the bitstream, all or part of the bitstream is non-conforming.

Abstract: Provided are methods, apparatus, and computer-readable medium for processing video data by a video coding system that implements ST 2094-10. Video data can include at least two video signals, which can be displayed at the same time in different display regions of a video frame. In various implementations, various techniques can be used to determine an association between a set of color volume parameters and a video signal, and this association can be encoded into a bitstream. Upon decoding of the bitstream, the set of color volume parameters associated with a particular video signal can be used to compress the color volume of the video signal into a range that can be displayed by a particular display device.

Abstract: A device for decoding video data may be configured to determine a block of the video data is coded using a palette-based coding mode; determine a sample of the block of video data is coded using a copy from top mode or an index mode; and decode a greater than zero flag to indicate whether a run value is greater than zero, wherein the run value specifies a number of samples subsequent to the sample that have a same mode as the sample.

Abstract: A video coder may determine a palette predictor list comprising one or more candidates. Each respective candidate in the palette predictor list specifies a value of a different respective reconstructed neighboring pixel from among one or more reconstructed neighboring pixels. Each of the one or more reconstructed neighboring pixels is in a line above or a column left of a current block of the video data. The video coder may include, in a palette for the current block, at least one candidate in the palette predictor list.

Abstract: This disclosure describes techniques for coding video data according to an intra Block Copy (BC) coding mode. A block vector difference that identifies a prediction block may be represented by a plurality of syntax elements, which may be encoded and decoded. This disclosure proposes various techniques whereby a video encoder may conditionally signal syntax elements representing the absolute value and/or sign of the components of the block vector difference. Likewise, a video decoder may be configured to infer the values of the syntax elements representing the absolute value and/or sign of the components of the block vector difference when such syntax elements are not signaled.

Abstract: In general, this disclosure describes techniques for coding video blocks using a color-space conversion process. A video coder, such as a video encoder or a video decoder, may determine whether to use color-space conversion for a coding unit and set a value of a syntax element of the coding unit to indicate the use of color-space conversion. The video coder may apply a color-space transform process in encoding the coding unit. The video coder may decode the syntax element of the coding unit. The video coder may determine whether a value of the syntax element indicates that the coding unit was encoded using color-space conversion. The video coder may apply a color-space inverse transform process in decoding the coding unit in response to determining that the syntax element indicates that the coding unit was coded using color-space conversion.

Abstract: Techniques are described for updating a value of a Rice parameter used to define Golomb codes for coefficient level coding. The Golomb codes defined by the Rice parameter may be used to code a remaining absolute value of a coefficient level for at least one coefficient in a coefficient group (CG). According to the techniques, the value of the Rice parameter is updated based on a selection of a minimum of either a maximum value of the Rice parameter or a variable increment of the value of the Rice parameter. The variable increment is determined based on the value of the Rice parameter and an absolute value of the coefficient level for the current coefficient being coded. Techniques are also described for adjusting the value of the Rice parameter used to define Golomb codes for coefficient level coding based on whether a transform is applied to a transform block.

Abstract: An example method for decoding video data includes receiving syntax elements (SEs) for a component of a block vector that represents a displacement between a current block of video data and a predictor block of video data; decoding the SEs to determine a value of the component by at least: decoding a first SE to determine whether or not an absolute value of the component (AbsValcomp) is greater than zero; where AbsValcomp is greater than zero, decoding a second SE to determine whether AbsValcomp is greater than a threshold based on an order of a set of codes; where AbsValcomp is greater than the threshold, decoding, using the set of codes, a third SE to determine AbsValcomp minus an offset based on the order of the set of codes; and where AbsValcomp is greater than zero, decoding a fourth SE to determine a sign of the value of the component.

Abstract: Techniques are described for palette-based video coding. In palette-based coding, a video coder may form a so-called “palette” as a table of colors for representing video data of a given block of video data. Rather than coding actual pixel values or their residuals for the given block, the video coder may code index values for one or more of the pixels. The index values map the pixels to entries in the palette representing the colors of the pixels. Techniques are described for determining the application of deblocking filtering for pixels of palette coded blocks at a video encoder or a video decoder. In addition, techniques are described for determining quantization parameter (QP) values and delta QP values used to quantize escape pixel values of palette coded blocks at the video encoder or the video decoder.

Abstract: Methods and apparatus are provided for signaling intra prediction for large blocks for video encoders and decoders. An apparatus includes a video encoder (400) for encoding picture data for at least one large block in a picture by signaling intra prediction for the at least one large block. The intra prediction is signaled by selecting a basic coding unit size and assigning a single spatial intra partition type for the basic coding unit size. The single spatial intra partition type is selectable from among a plurality of spatial intra partition types. The at least one large block has a large block size greater than a block size of the basic coding unit. The intra prediction is hierarchical layer intra prediction and is performed for the at least one large block by at least one of splitting from the large block size to the basic coding unit size and merging from the basic coding unit size to the large block size.

Abstract: This disclosure describes techniques for communicating optimal coding parameters between a source device and a sink device. The sink device may receive, in a bitstream, video data and a group of one or more supplemental enhancement information (SEI) messages, wherein each SEI message comprises indications of a set of display capabilities and a set of remapping parameters. The sink device may then, for each SEI message of the group of one or more SEI messages, compare the respective set of display capabilities indicated in the respective SEI message with a target set of display capabilities for the sink device. Responsive to determining that a first set of display capabilities indicated by a first SEI message is compatible with the target set of display capabilities, the sink device may adapt the video data using a respective set of remapping parameters indicated by the first SEI message.

Abstract: The disclosure describes deblock filtering techniques. A video coder may determine an amount by which to deblock filter a pixel value of a pixel based on a geometrical distance from the pixel to a boundary and a pixel value difference between pixel values of at least two pixels. The video coder may then deblock filter the pixel based on the determined amount.

Abstract: An example method of decoding video data includes determining a palette for decoding a block of video data, where the palette includes one or more palette entries each having a respective palette index, determining a first plurality of palette indices for first pixels of the block of video data, enabling a palette coding mode based on a run length of a run of a second plurality of palette indices for second pixels of the block of video data being decoded relative to the first plurality of palette indices meeting a run length threshold, and decoding the run of the second plurality of palette indices relative to the first plurality of palette indices using the palette coding mode.

Abstract: Techniques are described for palette-based video coding. In palette-based coding, a video coder may form a “palette” as a table of colors for representing video data of a particular area (e.g., a given block). Rather than coding actual pixel values (or their residuals), the video coder may code palette index values for one or more of the pixels that correspond to entries in the palette representing the colors of the pixels. A palette may be explicitly encoded, predicted from previous palette entries, or a combination thereof. In this disclosure, techniques are described for coding a block of video data that has a single color value using a single color mode as a sub-mode of a palette coding mode. The disclosed techniques enable a block having a single color value to be coded with a reduced number of bits compared to a normal mode of the palette coding mode.

Abstract: In one example, a method includes determining, by a video decoding unit, a peak brightness value of a current display; obtaining, by the video decoding unit and for a picture of video data, one or more colour remapping messages that each correspond to a respective peak brightness value of a set of peak brightness values; selecting, by the video decoding unit and based on the peak brightness value of the current display, a colour remapping message of the one or more colour remapping messages; colour remapping, by the video decoding unit and based on the selected colour remapping message, samples of the picture of video data; and outputting, by the video decoding unit and for display at the current display, the colour remapped samples of the picture of video data.

Abstract: A device for coding video data is configured to: determine a coding unit of a picture of the video data is coded using an intra block copy mode; determine a vector for a first chroma block of the coding unit; locate a first chroma reference block using the vector, the first chroma reference block being in the picture; predict the first chroma block based on the first chroma reference block; locate a second chroma reference block using the vector, the second chroma reference block being in the picture; and predict a second chroma block of the coding unit based on the second chroma reference block.

Abstract: In an example, system and method for coding encoded video data. A quantized residue differences block associated with a current block of a picture is generated and a reconstructed prediction residue for each quantized residue difference in the block of quantized residue differences is generated. Each reconstructed prediction residue is added to its corresponding original prediction value to produce a current block of a picture. Generating the reconstructed prediction residue includes performing inverse quantization on blocks of quantized residue differences, wherein the inverse quantization reconstructs data to which uniform quantization residue differential pulse code modulation (RDPCM) has been applied and wherein the quantization is of the form: ?Xq=floor((X+?Q)/Q) where Q is quantization step and ? is quantization offset.

Abstract: In palette-based coding, a video coder may form a so-called “palette” as a table of colors representing the video data of a given block. The video coder may code index values for one or more pixels values of a current block of video data, where the index values indicate entries in the palette that represent the pixel values of the current block. A method includes determining a number of entries in a palette, and determining whether a block of video data includes any escape pixels not associated with any entry in the palette. The method includes responsive to determining that the number of entries is one, and that the block does not include any escape pixels, bypassing decoding index values for the pixel values of the block, and determining the pixel values of the block to be equal to the one entry in the palette.