Abstract: An intra prediction method includes: based on a specific transform unit size, estimating a plurality of best intra prediction modes of a plurality of second blocks, wherein a first block is composed of the second blocks, the first block supports a first block configuration and a second block configuration, the first block configuration represents a size of the first block, and the second block configuration represents a size of each second block; and checking similarity of the best intra prediction modes of the second blocks for selectively replacing the second block configuration by the first block configuration for the first block.

Abstract: A method of IntraBC (Intra-block copy) coding for a coding region is disclosed. Embodiments of the present invention derive an IntraBC (Intra picture block copy) predictor from a constrained previous reconstructed region so as to reduce storage requirement for the previous reconstructed data. In one embodiment, a maximum absolute vertical BV (block vector) value, MaxV_BV is determined, where MaxV_BV is smaller than a full vertical search range for the coding region. A constrained previous reconstructed region corresponding to previous reconstructed samples processed before the current block is then determined, where the constrained previous reconstructed region includes at least MaxV_MV reconstructed samples in vertical direction above the current block and excludes at least one row of reconstructed samples for the current block with a vertical distance larger than MaxV_MV. Each coding block may correspond to a prediction unit (PU) or a coding unit (CU).

Abstract: 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.

Abstract: An exemplary video encoding apparatus has a video encoder, a transmitter, and a control circuit. The video encoder encodes a video sequence into a compressed video bitstream. The transmitter transmits the compressed video bitstream via a communication link. The control circuit adaptively adjusts an encoding behavior of the video encoder according to at least a transmission status of the communication link.

Abstract: A method and apparatus for video encoding with multi-level regions of interest is disclosed. According to the present invention, a target frame in the input video data is configured into multiple-level region-of-interest (ROI) regions. Each target higher-level ROI region is located within one target lower-level ROI region. The multiple-level ROI regions are then encoded according to a plurality of quality levels, where at least two different quality levels are applied to two different multiple-level ROI regions respectively.

Abstract: A video encoding apparatus has a bitstream buffer and a first video encoder. The first video encoder sequentially encodes coding blocks of a first video frame segment in a first encoding order, and outputs encoded data of the coding blocks of the first video frame segment to the bitstream buffer. The first video frame segment is partitioned into a plurality of column tiles, each having at least one tile. The first encoding order is identical to an encoding order of encoding a video frame segment with only a single column tile.

Abstract: An apparatus and method for video encoding with low latency is disclosed. The apparatus comprises a video encoding module to encode input video data into compressed video data, one or more processing modules to provide the input video data to the video encoding module or to further process the compressed video data from the video encoding module, and one data memory associated with each processing module to store or to provide shared data between the video encoding module and each processing module. The encoding module and each processing module are configured to manage data access of one data memory by coordinating one of the video encoding module and one processing module to receive target shared data from one data memory after the target shared data from another of the video encoding module and one processing module are ready in said one data memory.

Abstract: A video encoder has a processing circuit and a universal binary entropy (UBE) syntax encoder. The processing circuit processes pixel data of a video frame to generate encoding-related data, wherein the encoding-related data comprise at least quantized transform coefficients. The UBE syntax encoder processes a plurality of syntax elements to generate UBE syntax data. The encoding-related data are represented by the syntax elements. The processing circuit operates according to a video coding standard. The video coding standard supports arithmetic encoding. The UBE syntax data contain no arithmetic-encoded syntax data.

Abstract: An image processing method includes at least following steps: partitioning a picture into a plurality of picture regions, wherein each picture region comprises at least one pixel group row, each pixel group row comprises at least one pixel group, and the picture regions comprise a first picture region and a second picture region horizontally adjacent to each other; and performing flatness check upon a specific pixel group in a pixel group row of the first picture region through using at least one pixel borrowed from the second picture region.

Abstract: A method or apparatus of configuring a multi-channel coding device for use as a single-channel coding device is provided. The multi-channel coding device reconfigured as a single-channel coding device performs encoding or decoding of the pixels for a first color channel while substituting the pixels of a second color channel with predetermined (e.g., fixed) values. The reconfigured coding device may output reconstructed pixels of the first color channel but not reconstructed pixels of the second color channel.

Abstract: One exemplary video encoding method has the following steps: determining a size of a parallel motion estimation region according to encoding related information; and encoding a plurality of pixels by at least performing motion estimation based on the size of the parallel motion estimation region. One exemplary video decoding method has the following steps: decoding a video parameter stream to obtain a decoded size of a parallel motion estimation region; checking validity of the decoded size of the parallel motion estimation region, and accordingly generating a checking result; when the checking result indicates that the decoded size of the parallel motion estimation region is invalid, entering an error handling process to decide a size of the parallel motion estimation; and decoding a plurality of pixels by at least performing motion estimation based on the decided size of the parallel motion estimation region.

Abstract: One exemplary image encoding method for encoding an image includes following steps: calculating a mean value of each color channel of a plurality of reconstructed pixels; determining a first predictor used by a first candidate coding mode of a current coding block according to mean values of color channels of the reconstructed pixels; determining a second predictor used by a second candidate coding mode of the current coding block according to the mean values of the color channels of the reconstructed pixels, wherein determining the first predictor and determining the second predictor are performed in a parallel manner; determining a coding mode selected from candidate coding modes including at least the first candidate coding mode and the second candidate coding mode; and encoding the current coding block into a part of a bitstream according to at least the determined coding mode.

Abstract: An image processing method includes at least following steps: partitioning a picture into a plurality of picture regions, wherein each picture region comprises at least one pixel group row, each pixel group row comprises at least one pixel group, and the picture regions comprise a first picture region and a second picture region horizontally adjacent to each other; and performing flatness check upon a specific pixel group in a pixel group row of the first picture region through using at least one pixel borrowed from the second picture region.

Abstract: An entropy encoding method includes following steps: receiving symbols of a pixel group; entropy encoding data derived from the symbols of the pixel group to generate a first bitstream portion and a second bitstream portion, wherein the first bitstream portion includes encoded magnitude data of the symbols of the pixel group, and the second bitstream portion includes encoded sign data of at least a portion of the symbols of the pixel group; and generating a bitstream segment of the pixel group by combining at least the first bitstream portion and the second bitstream portion. The pixel group includes a plurality of pixels, and the symbols of the pixel group have a plurality of symbol values of the pixels, respectively. When a first symbol value has a zero magnitude value, a sign value of the first symbol value is not entropy encoded into the second bitstream portion.

Abstract: An image encoding method for encoding an image includes following steps: determining a coding mode selected from a plurality of candidate coding modes for a current coding block, wherein the current coding block included in the image comprises a plurality of pixels; and encoding the current coding block into a part of a bitstream according to at least the determined coding mode. The step of encoding the current coding includes: determining a first predictor presented in a first color space according to a plurality of reconstructed pixels presented in the first color space; transforming the first predictor presented in the first color space to a second predictor presented in a second color space different from the first color space; and encoding the current coding block under the second color space according to at least the second predictor.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Methods for determining reference type of each image unit and adjusting the corresponding lambda table of the reference type are disclosed. Embodiments according to the invention are used to improve the quality of video compression or reduce the requirement of memory buffer, memory power or computation power. The reference type is determined based on the encoder system information or image unit information. The frame/slice type structure of a video sequence is adjusted according to the image unit information of encoded frames or together with input frames. By fine-tuning the mode decision process, the coding efficiency can be improved. The mode decision process is modified by adaptively adjusting the lambda table. The lambda table is adaptively determined according to the conventional image unit type (such as Intra coded, predicted or bi-directional predicted type) and the reference type determined.

Abstract: A method and apparatus of image coding including adaptive entropy coding are disclosed. According to this method, input pixels associated with a group of symbols generated from image or video data are received. Maximum bit-depth of the group of symbols is then determined. If the maximum bit-depth of the group of symbols is smaller than a first bit-depth threshold, the group of symbols is encoded or decoded using Golomb-Rice coding. If the maximum bit-depth of the group of symbols is greater than or equal to the first bit-depth threshold, the group of symbols is encoded or decoded using second entropy coding, where the second entropy coding is different from the Golomb-Rice coding. Outputs corresponding to encoded or decoded output associated with the group of symbols are provided. The maximum bit-depth of the group of symbols is signaled at the encoder or recovered at the decoder by parsing the bitstream.