Qualcomm Incorporated

Samsung Display Co., Ltd.

Samsung Displayco., Ltd.

Vijayaraghavan Thirumalai

Rajan Laxman Joshi

Natan Jacobson

Marta Karczewicz

Li Feng Zhang

Xin Zhao

Vadim Seregin

Ying Hai Chen

Nan Hu

Wei-Jung Chien

Amir Said

Min Dai

Xiang Yang Li

Hsiao-Chiang Chuang

Ike Ikizyan

Kai Zhang

Hongbin Liu

Cheng-Teh Hsieh

Jalil Kamali

Ying Chen

Natan Haim Jacobson

A method for decoding image content from an encoded bitstream including a plurality of blocks includes: dividing a block including one or more components of the image content into N single samples and M sample groups corresponding to one of the components, where N and M are greater than or equal to one; decoding each of the N single samples using a symbol variable length code to generate one or more decoded single samples; decoding each of the M sample groups using a common prefix entropy code to generate one or more decoded sample groups, each of the M sample groups including a variable length prefix and one or more fixed length suffixes representing a plurality of samples; concatenating the decoded single samples and the decoded sample groups into a block of residuals; and reconstructing image content based on previously reconstructed neighboring blocks and the block of residuals.

Systems and methods for scalable throughput entropy coders

A method of compressing a frame in an image compression and storage system, the method including applying a modulo addition to a residue of an original sample of the frame to generate a biased residue based on a bit depth of the original sample and a maximum allowed error, quantizing the biased residue based on the maximum allowed error to generate a quantized biased residue, and encoding a value corresponding to the quantized biased residue to generate an encoded value that has a non-negative reconstruction error.

Compression with positive reconstruction error

A method of compressing a frame in an image compression and storage system includes mapping an original sample to a mapped sample based on a bit depth of the original sample and a maximum allowed error, determining a residue of the mapped sample based on a mapped previous reconstructed sample, applying a modulo addition to the residue to generate a biased residue, quantizing the biased residue based on the maximum allowed error to generate a quantized biased residue, and encoding a value corresponding to the quantized biased residue to generate an encoded value.

DPCM codec with higher reconstruction quality on important gray levels

A method includes receiving an image frame comprising pixels, wherein each pixel comprises n color channels, generating, by a separate color channel quantization branch for each of the n color channels configured to guarantee a non-negative reconstruction error, a first sample set of quantized indices based on color values of residues for a first particular pixel in the image frame, wherein the first sample set corresponds to a first n-tuple, and generating, by an entropy encoder, an entropy encoding for the first particular pixel based on data that maps indices to n-tuples of quantized indices, wherein the first n-tuple is mapped to a first index.

Systems and methods for joint color channel entropy encoding with positive reconstruction error

Provided is a method of coding blocks of video data representing an image using an encoder, the method including identifying, by the encoder, a first region of the image and a second region of the image, a sum of a first number of pixels in the first region and a second number of pixels in the second region being equal to a total number of pixels of the image, and allocating, by the encoder, a first number of bits including base bits for encoding the first region, and a second number of bits including base bits and enhancement bits for encoding the second region, a sum of the first number of bits and the second number of bits being equal to a total number of bits for encoding all of the pixels, wherein the second region is encoded with a greater number of bits per pixel than the first region.

Rate control for fixed rate foveated display compression

A method of compressing a frame in an image compression and storage system includes mapping an original sample to a mapped sample based on a bit depth of the original sample and a maximum allowed error, to ensure low reconstruction error for a high priority sample value, determining a residue of the mapped sample based on a mapped previous reconstructed sample, applying a modulo addition to the residue to generate a biased residue, quantizing the biased residue based on the maximum allowed error to generate a quantized biased residue, and encoding a value corresponding to the quantized biased residue to generate an encoded value.

Systems and methods for scalable throughput entropy coder

A video coder determines a first block of the video data is intra mode coded; based on a first height and the first width of the first block, identifies a group of N available intra prediction modes for the first block of video data; selects from the group of N available intra prediction modes, a first intra prediction mode used to code the first block of the video data; and codes the first block using the first intra prediction mode. A video coder generates a first most probable mode (MPM) candidate list for the block; codes a first flag indicating an actual intra prediction mode used to code the block is not included in the first MPM candidate list; generates a second MPM candidate list by deriving at least one candidate intra prediction mode based on an intra prediction mode in the first MPM candidate list.

Variable number of intra modes for video coding

Systems and methods for performing rate-distortion optimization includes receiving an original data corresponding to a block of an image frame, and identifying a reconstructed version of the original data that minimizes a cost function. The cost associated with a particular reconstructed version of the original data may be based on an encoding rate associated with the particular reconstructed version of the original data, and a distortion between the original data and the particular reconstructed version of the original data in response to a supremum norm of error between the original data and the particular reconstructed version of the original data being less than or equal to a threshold value.

Systems and methods for compression with constraint on maximum absolute error

A method for encoding data includes: receiving a frame of data including subunits; initializing a remaining bit budget for the frame; setting a current codec to a lossless codec having a lossless codec bitrate; and sequentially encoding the subunits, including: encoding a first subunit using the lossless codec to compute a first encoded sub-unit; subtracting a length of the first encoded subunit from the remaining bit budget; determining whether the remaining bit budget exceeds a first lossy bits required to encode a plurality of remaining subunits using a first lossy codec having a first lossy codec bitrate lower than the lossless codec bitrate; in response to determining that the remaining bit budget is less than or equal to the first lossy bits required, setting the current codec to the first lossy codec; and encoding a second subunit using the first lossy codec to compute a second encoded sub-unit.

Systems and methods for low-complexity near lossless fixed-rate hybrid data compression codecs

A video coding device (e.g., a video encoder or a video decoder) is configured to perform various transformations on video data. The video coding device applies a primary transform to a block of the video data, the primary transform having a first size, and the sub-block being at least a portion of the block. The video coding device determines whether application of a secondary transform, having a second size, to a sub-block of the block is allowed. Application of the secondary transform is disallowed when the first size is equal to the second size. Based on the application of the secondary transform being allowed, the video coding device applies the secondary transform to the sub-block. Application of the primary transform and the secondary transform construct a residual block in a pixel domain.

Primary transform and secondary transform in video coding

A device for coding video data is configured to determine that a current block of video data is coded using an intra prediction mode; add an intra prediction mode of a first neighboring block of the current block to a most probable mode candidate list for the current block; add an intra prediction mode for a second neighboring block of the current block to the most probable mode candidate list for the current block; add an intra prediction mode for a third neighboring block of the current block to the most probable mode candidate list for the current block; and code the current block of video data using an intra prediction mode.

Neighbor based signaling of intra prediction modes

A device for video decoding may include a memory configured to store video data and a processor configured receive a bitstream including encoded video data. The processor may be configured to select a number of template matching (TM) candidates for a temporal layer or slice during the video decoding. The number of TM candidates selected are fixed prior to the video decoding, or adaptively calculated during the video decoding. The processor may be configured to generate a prediction block and residual block, based on a template matching candidate, to reconstruct the video data.

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San Diego, CA, United States of America

Vijayaraghavan Thirumalai