公开(公告)号：US20200236375A1

公开(公告)日：2020-07-23

申请号：US16838529

申请日：2020-04-02

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Yaowu Xu

IPC: H04N19/436 ,  H04N19/82 ,  H04N19/14 ,  H04N19/117 ,  H04N19/86 ,  H04N19/176

Abstract: An apparatus for video coding using dual deblocking filter thresholds may include a processor generating a reconstructed frame by decoding an encoded bitstream and outputting the reconstructed frame. Decoding may include generating a decoded block by decoding a portion of the encoded bitstream, identifying a first deblocking threshold index from the encoded bitstream, identifying a second deblocking threshold index from the encoded bitstream, generating a reconstructed block based on the decoded block, and including the reconstructed block in the reconstructed frame. Generating the reconstructed block may include deblocking based on the first deblocking threshold index and the second deblocking threshold index.

公开(公告)号：US20200099956A1

公开(公告)日：2020-03-26

申请号：US16693438

申请日：2019-11-25

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  James Zern ,  Linfeng Zhang ,  Ching-Han Chiang ,  Yaowu Xu

IPC: H04N19/60 ,  H04N19/129 ,  H04N19/13 ,  H04N19/184 ,  H04N19/88

Abstract: A memory of an apparatus includes instructions executable by a processor to select a backward scan order for traversing, along scan-order anti-diagonal lines, a block of values related to the transform coefficients; select a template for entropy-coding the values, the template indicating, for a to-be-coded value, scan positions of already coded values, the scan positions arranged in at least two template anti-diagonal lines; maintain, for coding first values, where the first values are arranged along a current scan-order anti-diagonal line, a first line buffer and a second line buffer; for a current value of the current scan-order anti-diagonal line, determine a context using the first line buffer and the second line buffer, and entropy encode, in a compressed bitstream, the current value using the context; and replace one of the second line buffer or the first line buffer with the current scan-order anti-diagonal line.

公开(公告)号：US10567772B2

公开(公告)日：2020-02-18

申请号：US15646370

申请日：2017-07-11

Applicant: GOOGLE LLC

Inventor： Yaowu Xu ,  Jingning Han

IPC: H04N19/103 ,  H04N19/137 ,  H04N19/44 ,  H04N19/593 ,  H04N19/13 ,  H04N19/159 ,  H04N19/176 ,  H04N19/51 ,  H04N19/186 ,  H04N19/124

Abstract: Methods and apparatuses for coding a current block are disclosed. An apparatus for decoding a current block of size 8×8 including a memory and a processor is also disclosed. The processor configured to execute instructions stored in the memory to generate, for the current block, a luma block and a chroma block, divide the luma block into luma sub-blocks, and determine a respective prediction mode for each luma sub-block. The chroma block is of size 4×4, each luma sub-block is of size 4×4, and the respective prediction mode is an intra-mode or an inter-mode. The instructions also include instructions to, on condition that each of the respective prediction modes is the inter-mode, divide the chroma block into 2×2 chroma sub-blocks and determine a respective motion vector for each chroma sub-block.

公开(公告)号：US20200029098A1

公开(公告)日：2020-01-23

申请号：US16042261

申请日：2018-07-23

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Aki Kuusela ,  Stanislav Vitvitskyy ,  Yaowu Xu ,  Ching-Han Chiang ,  Dake He

IPC: H04N19/91 ,  H04N19/70 ,  H04N19/61 ,  H04N19/44

Abstract: Asymmetric probability model updating and entropy coding includes using different numbers of bits for storing probabilities of a probability model and for entropy coding symbols using that probability model. The probabilities of a probability model are updated according to values of syntax elements decoded from a bitstream. The probabilities are associated with possible values of the syntax elements and are stored using a first bit precision. Based on the updated probabilities, a second bit precision to use to entropy decode the syntax elements is determined. The second bit precision is less than the first bit precision. The syntax elements are then entropy decoded using the second bit precision, such as to produce quantized transform coefficients, which may be further processed and output to an output video stream. Using the first bit precision to entropy decode the syntax elements results in a lower compression throughput than using the second bit precision.

公开(公告)号：US20190394491A1

公开(公告)日：2019-12-26

申请号：US16016980

申请日：2018-06-25

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Yaowu Xu

IPC: H04N19/66 ,  H04N19/119 ,  H04N19/50 ,  H04N19/96 ,  H04N19/192 ,  H04N19/176

Abstract: Multi-stage coding block partition search is disclosed. A method includes selecting a partition-none partition type and a partition-split partition type for predicting the block, determining a first cost of predicting the block using the partition-none partition type, and determining a second cost of predicting the block using the partition-split partition type. The partition-none partition type and the partition-split partition type are selected from a set of partition types that includes the partition-none partition type, the partition-split partition type, and third partition types. The method also includes, on condition that the result meets a criterion, determining a respective encoding cost corresponding to at least some of the third partition types; selecting a selected partition type corresponding to a minimal cost amongst the partition-none partition type and the at least some of the third partition types; and encoding, in a compressed bitstream, the selected partition type.

公开(公告)号：US10462472B2

公开(公告)日：2019-10-29

申请号：US15935301

申请日：2018-03-26

Applicant: GOOGLE LLC

Inventor： Debargha Mukherjee ,  Jingning Han

IPC: H04N19/176 ,  H04N19/119 ,  H04N19/147 ,  H04N19/122 ,  H04N19/63 ,  H04N19/00

Abstract: Coding efficiency may be improved by subdividing a block into smaller sub-blocks for prediction. A first rate distortion value of a block optionally partitioned into smaller prediction sub-blocks of a first size is calculated using respective inter prediction modes and transforms of the first size. The residuals are used to encode the block using a transform of a second size smaller than the first size, generating a second rate distortion value. The values are compared to determine whether coding efficiency gains may result from inter predicting the smaller, second size sub-blocks. If so, the block is encoded by generating prediction residuals for the second size sub-blocks, and neighboring sub-blocks are grouped, where possible, based on common motion information. Each resulting composite residual block is transformed by a transform of the same size to generate another rate distortion value. The encoded block with the lowest rate distortion value is used.

公开(公告)号：US10455253B1

公开(公告)日：2019-10-22

申请号：US15445063

申请日：2017-02-28

Applicant: GOOGLE LLC

Inventor： Stanislav Vitvitskyy ,  Jingning Han ,  Ching-Han Chiang ,  Adrian W. Grange

IPC: H04N7/00 ,  H04N19/52 ,  H04N19/117 ,  H04N19/80 ,  H04N19/51

Abstract: A first interpolation filter is selected for a first direction of the prediction block, and a second interpolation filter is selected for a second direction of the prediction block. The first interpolation filter has a first number of taps and the second interpolation filter has a second number of taps. The second interpolation filter is set to an interpolation filter having a third number of taps in response to determining that the first number of taps is greater than a threshold number of taps and the second number of taps is greater than a threshold number of taps. The third number of taps is smaller than or equal to the threshold number of taps. The prediction block is generated using the first interpolation filter and the second interpolation filter.

公开(公告)号：US20190313123A1

公开(公告)日：2019-10-10

申请号：US16451415

申请日：2019-06-25

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Ching-Han Chiang

IPC: H04N19/60 ,  H04N19/192 ,  H04N19/136 ,  H04N19/129 ,  H04N19/176 ,  H04N19/91 ,  H04N19/18 ,  H04N19/134

Abstract: Video coding using a context adaptive scan order for entropy coding may include an apparatus decoding a current block by identifying a context adaptive scan order for entropy decoding a transform block, which may include identifying non-zero-coefficient probabilities for the transform block such that each location in the transform block corresponds to a respective non-zero-coefficient probability from the non-zero-coefficient probabilities, assigning a respective context adaptive scan order position to each location in the transform block in descending magnitude order of the respective corresponding non-zero-coefficient probabilities such that the context adaptive scan order position for each location exceeds the context adaptive scan order position assigned to entropy coding context locations for the respective location, entropy decoding transform coefficients from the encoded video stream based on the context adaptive scan order, and reconstructing the decoded block based on the transform block.

公开(公告)号：US20190268617A1

公开(公告)日：2019-08-29

申请号：US15131079

申请日：2016-04-18

Applicant: GOOGLE LLC

Inventor： Yaowu Xu ,  Jingning Han

IPC: H04N19/52 ,  H04N19/176 ,  H04N19/109 ,  H04N19/44 ,  H04N19/527 ,  H04N19/139 ,  H04N19/159

Abstract: Techniques are described to use a reference motion vector to reduce the amount of bits needed to encode motion vectors for inter prediction. One method includes identifying a candidate motion vector used to inter predict each of a plurality of previously coded blocks to define a plurality of candidate motion vectors, determining a distance between the previously decoded block associated with the candidate motion vector and a current block, determining a popularity value for each candidate motion vector based on a set of previously coded pixels associated with the candidate motion vector, and ranking the candidate motion vectors according to a priority value for each candidate motion vector. The priority value, based on the distance and the popularity value associated with the candidate motion vector, is used to select a reference motion vector from the candidate motion vectors that is used to encode the motion vector for the current block.

公开(公告)号：US10382758B2

公开(公告)日：2019-08-13

申请号：US15880939

申请日：2018-01-26

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Dake He

IPC: H04N7/12 ,  H04N11/02 ,  H04N11/04 ,  H04N19/129 ,  H04N19/61 ,  H04N19/82 ,  H04N19/176 ,  H04N19/18

Abstract: A scan order for encoding or decoding coefficients of a transform block is selected on a transform block-level. A set of candidate scan orders is processed by identifying end of block positions within the transform block for each of the candidate scan orders. Cost values are determined for each of the candidate scan orders to reflect a number of the coefficients of the transform block that are located before the respective end of block positions. In particular, a cost value for a candidate scan order reflects the number of zero-value coefficients located before the end of block position for that candidate scan order. One of the candidate scan orders is then selected based on those cost values. The selected scan order is used to scan the coefficients in the transform block, such as for encoding those coefficients to a bitstream or for decoding those coefficients to an output video stream.