Mediatek Corporation

Tung-Hsing Wu

Han-Liang Chou

Kun-Bin Lee

Li-Heng Chen

Chi-Cheng Ju

Ting-An Lin

Lien-Fei Chen

Yi-Hsin Huang

Yung-Chang Chang

Tsu-Ming Liu

Chung-Hua Tsai

Chih-Hao Chang

Chih-Ming Wang

Chia-Yun Cheng

Ping Chao

Wan-Yu Chen

Ping-Han Lee

Ming-Long Wu

Hsin-Hao Chung

Jia-Ying Lin

I-Hsuan Lee

Tzu-Yun Tseng

Kung-Tsun Yang

Chuang-Chi Chiou

Yu-Kun Lin

Ping-yao Wang

Wei-Gen Wu

Chang-Hung Tsai

Chung Hsien Lee

Yi-Hao Wu

Yu Kun Lin

Shih-Yu Chen

Jer-Ming Chang

A video encoding apparatus includes a content activity analyzer circuit and a video encoder circuit. The content activity analyzer circuit applies a content activity analysis process to consecutive frames, to generate content activity analysis results. The consecutive frames are derived from input frames of the video encoding apparatus. The content activity analysis process includes: deriving a first content activity analysis result according to a first frame and a second frame in the consecutive frames, wherein the first content activity analysis result includes a processed frame distinct from the second frame; and deriving a second content activity analysis result according to a third frame included in the consecutive frames and the processed frame. The video encoder circuit performs a video encoding process to generate a bitstream output of the video encoding apparatus, wherein information derived from the content activity analysis results is referenced by the video encoding process.

Video encoding apparatus for performing video compression with aid of content activity analysis and associated video encoding method

A video encoding method includes: during a first period, performing an encoding process upon a first block group of a current frame to generate a first block group bitstream; and during a second period, transmitting a second block group bitstream derived from encoding a second block group of the current frame, wherein the second period overlaps the first period. The encoding process includes: during a first time segment of the first period, performing a first in-loop filtering process upon a first group of pixels; and during a second time segment of the first period, performing a second in-loop filtering process upon a second group of pixels, wherein the second time segment overlaps the first time segment, and a non-zero pixel distance exists between a first edge pixel of the first group of pixels and a second edge pixel of the second group of pixels in a filter direction.

Video encoding method using multiple in-loop filters in low latency video encoding and associated video encoding apparatus

A video encoding apparatus includes a data buffer and a video encoding circuit. Encoding of a first frame includes: deriving reference pixels of a reference frame from reconstructed pixels of the first frame, respectively, and storing reference pixel data into the data buffer for inter prediction, wherein the reference pixel data include information of pixel values of the reference pixels. Encoding of a second frame includes performing prediction upon a coding unit in the second frame to determine a target predictor for the coding unit. The prediction performed upon the coding unit includes: determining the target predictor for the coding unit according to whether a search range on the reference frame for finding a predictor of the coding unit under an inter prediction mode includes at least one reference pixel of the reference frame that is not accessible to the video encoding circuit.

Video encoding apparatus having reconstruction buffer with fixed size and/or bandwidth limitation and associated video encoding method

A video encoding apparatus includes a data buffer and a video encoding circuit. Encoding of a first frame includes: deriving reference pixels of a reference frame from reconstructed pixels of the first frame, respectively, and storing reference pixel data into the data buffer for inter prediction, wherein the reference pixel data include information of pixel values of the reference pixels. Encoding of a second frame includes performing prediction upon a coding unit in the second frame to determine a target predictor for the coding unit. The prediction performed upon the coding unit includes: checking if a search range on the reference frame for finding a predictor of the coding unit under an inter prediction mode includes at least one reference pixel of the reference frame that is not accessible to the video encoding circuit, and determining the target predictor for the coding unit according to a checking result.

An encoding method is used for encoding an image. The image includes a plurality of blocks each having a plurality of pixels. The encoding method includes: encoding a plurality of data partitions of block data of a block in the image to generate a plurality of compressed bitstream segments, respectively; and combining the compressed bitstream segments to generate an output bitstream of the block. A bit group based interleaving process is involved in generating the output bitstream. According to the bit group based interleaving process, each of the compressed bitstream segments is divided into a plurality of bit groups each having at least one bit, and the output bitstream includes consecutive bit groups belonging to different compressed bitstream segments, respectively.

Method and apparatus for dealing with compressed bitstream interleaving

A video compression system includes a video encoder and a bitstream processing circuit. The video encoder is hardware that performs hardware video encoding upon frames to generate a first bitstream. The first bitstream is output from an entropy encoding circuit of the video encoder. The bitstream processing circuit performs a bitstream post-processing operation upon the first bitstream to produce a second bitstream that is different from the first bitstream, and outputs the second bitstream as a compression output of the frames.

Video compression system with post-processing of bitstream generated by hardware video encoding and associated video compression method

A perception-based image processing apparatus includes an image analyzing circuit and an application circuit. The image analyzing circuit obtains training data, sets a perception model according to the training data, performs an object detection of at least one frame, and generates an object detection information signal based at least partly on a result of the object detection of said at least one frame. The application circuit operates in response to the object detection information signal.

Perception-based image processing apparatus and associated method

A block prediction search method includes at least following steps: utilizing a data buffer to store bit-depth reduced sample values of a plurality of samples in a first pixel line; detecting occurrence of an edge in the first pixel line according to restored sample values derived from stored sample values in the data buffer; and determining a block prediction vector for a pixel group in a second pixel line different from the first pixel line, wherein the block prediction vector is determined based at least partly on a last edge count value indicative of a number of samples in the first pixel line that have gone by since the edge occurs.

Method and apparatus for performing block prediction search based on restored sample values derived from stored sample values in data buffer

A video encoder includes a video encoding circuit and a slice decision circuit. The video encoding circuit encodes a first slice in a frame according to a first coding unit boundary between an end of the first slice and a start of a second slice in the frame, and outputs a first bitstream of the first slice. The slice decision circuit predicts the first coding unit boundary before a bitstream of a last coding unit of the first slice is generated by the video encoding circuit, and informs the video encoding circuit of the first coding unit boundary. The video encoding circuit refers to the first coding unit boundary predicted by the slice decision circuit to ensure that a bitstream size of the first bitstream is constrained by a predetermined bitstream size threshold.

Method and apparatus for performing fixed-size slice encoding with slice boundary prediction

An entropy encoder includes an entropy encoding circuit and a size determining circuit. The entropy encoding circuit receives symbols of a pixel group, and entropy encodes data derived from the symbols of the pixel group to generate a bitstream segment which is composed of a first bitstream portion and a second bitstream portion. The first bitstream portion contains encoded magnitude data of the symbols of the pixel group, and the second bitstream portion contains encoded sign data of at least a portion of the symbols of the pixel group. The size determining circuit determines a size of a bitstream portion, wherein the bitstream portion comprises at least one of the first bitstream portion and the second bitstream portion.

Methods and apparatuses for performing entropy encoding and entropy decoding with size determination of at least one bitstream portion

A method and apparatus of image coding performed at an encoder or decoder using block prediction are disclosed. The block vector bit-count information associated with one or more block vectors (BVs) for the current block is determined, where the BVs are used to locate one or more block predictors for the current block. Prediction residuals corresponding to differences between the current block and the block predictors are determined. A first cost comprising the BV and residual bit-count information associated with encoding the prediction residuals using the first coding tool is determined. The second cost comprising the BV bit-count information and without the residual bit-count information is also determined. The derivation of the BV bit-count information and the prediction residuals for the current block are performed only once, and the BV bit-count information and the prediction residuals are used by the first coding tool and the second coding tool.

Method and apparatus for image compression using block prediction mode

An image processing method includes: combining a padding region with a picture, wherein any padding pixel included in the padding region is assigned with a predetermined pixel value; and encoding the picture having the padding region combined therewith. For example, the padding region is directly below a bottom edge of the picture. For another example, all of padding pixels included in the padding region have the same pixel value.

Method and apparatus for processing picture having picture height not evenly divisible by slice height and/or slice width not evenly divisible by pixel group width

A method and apparatus of image coding including a no-residue prediction mode are disclosed. At the encoder side, current predictors for a current coding unit are determined according to a target prediction process associated with a target prediction mode. The current predictors are determined based on pixel data including reconstructed pixels in the current slice or the current image. The target prediction process is applied to the current coding unit using the current predictors to generate prediction residues. A distortion condition or a cost measure for the prediction residues is determined. If the distortion condition is satisfied or the cost measure favors coding without the prediction residues, the current coding unit is encoded into current compressed bits of the current coding unit without compressed data associated with the prediction residues. A corresponding decoding method and apparatus are also disclosed.

Method and apparatus for image compression without residue signaling

Method and apparatus of image coding using block prediction (BP) allowing multiple block sizes are disclosed. According to one method, first distortion for the current block coded using BP with a first block size is derived using at least partial second distortion for the current block coded using BP with a first block size. According to another method, a flag indicating whether the BP using variable block sizes is enabled. According to yet another method, when a current block is coded using BP by partitioning the current block into multiple partitions, predictors for two partitions in different reconstructed pixel line groups are derived from different reconstructed pixel line groups. According to still yet another method, for coding image data in a non-444 color sampling format using BP, the predictors for chrominance pixels in the current block are derived from the predictors for the luminance pixels of the current block.

Method and apparatus for block prediction using variable block-size in image compression

Aspects of the disclosure provide a method for merging compressed access units according to compression rates and/or positions of the respective compressed access units. The method can include receiving a sequence of compressed access units corresponding to a sequence of raw access units partitioned from an image or a video frame and corresponding to a sequence of memory spaces in a frame buffer, determining a merged access unit including at least two consecutive compressed access units based on compression rates and/or positions of the sequence of compressed access units. The merged access unit is to be stored in the frame buffer with a reduced gap between the at least two consecutive compressed access units compared with storing the at least two consecutive compressed access units in corresponding memory spaces in the sequence of memory spaces.

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Chiayi, Taiwan

Tung-Hsing Wu