Abstract: 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.

Abstract: A method and apparatus of encoding using multiple coding modes with multiple color spaces are disclosed. Weighted distortion is calculated for each candidate mode and a target mode is selected according to information including the weighted distortion. Each candidate coding mode is selected from a coding mode group including at least a first coding mode and a second coding mode, where the first coding mode uses a first color space for encoding one block and the second coding mode uses a second color space for encoding one block, and the first color space is different from the second color space. The weighted distortion corresponds to a weighted sum of distortions of color channels for each color transformed current block using a set of weighting factors and the set of weighting factors is derived based on a color transform associated with a corresponding color space for each coding mode.

Abstract: A method and apparatus of coding using multiple coding modes with multiple color spaces are provided. For the encoder side, a coding mode is selected from a coding mode group. A corresponding color domain is associated with the coding mode and the corresponding color domain is selected from a color-domain group including at least two different color domains. The current coding unit is then encoded in the corresponding color domain using the coding mode. Furthermore, the syntax of the corresponding color domain is signaled in current coding unit syntaxes. The different color domains may include RGB color domain and YCoCg color domain. According to another method, if the midpoint prediction (MPP) mode is selected, a current block is color transformed into another color domain and the MPP coding process is performed in said another color domain.

Abstract: A method and apparatus of encoding frames with a frame type structure adaptively according to a current encoding status after receiving a request for an IDR frame or receiving an indication of picture data loss are disclosed. If the check result of the current encoding status is true, the second frame type structure is the same as the first frame type structure; and if the check result of the current encoding status is false, the second frame type structure is different from the first frame type structure. Another method and apparatus of encoding frames with a reference frame structure and a frame type structure adaptively according to one or more current encoding statuses after receiving an indication of picture data loss are disclosed. The system may use two different check results to adaptively select the reference frame structure and the frame type structure.

Abstract: A method and apparatus for processing transform coefficients for a video coder or encoder is disclosed in the present invention. Embodiments according to the present invention reduce the storage requirement for sign bit hiding (SBH), improve the parallelism of SBH processing or simplify parity checking. Partial quantized transform coefficients (QTCs) of a transform block may be processed before all QTCs of the transform block are received. Zero and non-zero QTCs of a scan block may be processed concurrently and the QTCs of multiple scan blocks in a transform block may also be processed concurrently when computing cost function for SBH compensation. The range for searching for a value-modification QTC may be less than the scan block to be processed. Parity checking on QTCs may be based on least significant bits (LSBs) of all QTCs or all non-zero QTCs of a scan block.

Abstract: A method and apparatus for encoding of video data incorporating loop filtering are disclosed. The method and apparatus according to an embodiment of the present invention determines an initial loop filter level for a frame of the video data according to quality setting of the frame. The information associated with the initial loop filter level is incorporated in the bitstream corresponding to compressed video data. The loop filtering is applied to a macroblock without the need to wait for the whole frame reconstruction to complete. In another embodiment according to the present invention, the initial loop filter level may be refined according to stability associated with the frame. In yet another embodiment according to the present invention, the method may include determining whether segment mode is on or off and determining a frame-level or segment-level initial loop filter level accordingly.

Abstract: An inter prediction method includes performing reference frame acquisition for inter prediction of a first frame in a first frame group to obtain at least one reference frame, and performing the inter prediction of the first frame according to the at least one reference frame. The at least one reference frame used by the inter prediction of the first frame is intentionally constrained to include at least one first reference frame obtained from reconstructed data of at least one second frame in the first frame group. The first frame group has at least one first frame, including the first frame, and the at least one second frame. Frames in the first frame group have a same image content but different resolutions.

Abstract: An image processing method includes at least the following steps: partitioning a picture into a plurality of slices, wherein each slice row in the picture includes at least one slice; generating a compressed picture by encoding each of the slices; and controlling at least one of start of transmission of encoded data of a slice row and end of the transmission of encoded data of the slice row according to a transmission synchronization event.

Abstract: 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.

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: Method and apparatus of video coding using coding modes including Intra Block Copy (IntraBC) for a video coding system incorporating multi-stage pipeline processing is disclosed. In order to overcome data dependency issue due to the use of pipeline architecture, a first embodiment uses constrained previous reconstructed region for IntraBC estimation by excluding unavailable reconstructed previous reconstructed data due to the multi-stage pipeline processing. In the second embodiment, the unavailable reconstructed data is replaced by source pixel data.

Abstract: An image encoding method with rate control includes at least the following steps: defining a plurality of candidate bit budgets corresponding to different pre-defined maximum encoded bit lengths for one coding unit respectively; when encoding pixel data of a plurality of pixels within a current coding unit of an access unit of a frame, determining a target bit budget selected from the candidate bit budgets and allocating the target bit budget to the current coding unit; and outputting encoded pixel data of the pixels within the current coding unit that is generated from the encoder, wherein a bit length of the encoded pixel data is smaller than or equal to the target bit budget.

Abstract: An image compression method includes at least the following steps: receiving a plurality of pixels of a frame, wherein pixel data of each pixel has a plurality of color channel data corresponding to a plurality of different color channels, respectively; encoding the pixel data of each pixel and generating bit-streams corresponding to the plurality of color channel data of the pixel, wherein the bit-streams corresponding to the plurality of color channel data of the pixel are separated; packing bit-streams of a same color channel data of different pixels into color channel bit-stream segments, wherein each of the bit-stream segments has a same predetermined size; and concatenating color channel bit-stream segments of the different color channels into a final bit-stream. Alternatively, color channel bit-stream segments of the same pixel are concatenated into a concatenated bit-stream portion, and concatenated bit-stream portions of different pixels are concatenated into a final bit-stream.

Abstract: A data processing apparatus includes a storage element and a clock controller. The storage element has storage partitions, including a first storage partition and a second storage partition. The clock controller controls clock driving of the first storage partition and the second storage partition. When a processing circuit is configured to operate in a first condition to process a first data sample with a first bit width, the clock controller enables clock driving of both of the first storage partition and the second storage partition. When the processing circuit is configured to operate in a second condition to process a second data sample with a second bit width, the clock controller enables clock driving of the first storage partition and disables clock driving of the second storage partition.

Abstract: An encoding method includes applying a search range constraint on a search range of a block in a current frame, and encoding the block in the current frame with pixel information in a reference frame according to inter prediction performed based on the search range of the block in the current frame, wherein a resolution of the current frame is different from a resolution of the reference frame.

Abstract: An image encoding method includes at least following steps: receiving a plurality of target pixels within a frame, wherein pixel data of each target pixel has at least one color channel data corresponding to at least one color channel; determining a bit budget of the target pixels; and performing bit-plane scanning coding upon selected pixels according to the bit budget and a scanning order, and accordingly generating encoded pixel data of the selected pixels as encoded data of the target pixels, wherein the selected pixels are derived from the target pixels, and the bit-plane scanning coding extracts partial bits of pixel data of each selected pixel as encoded pixel data of the selected pixel. In addition, a corresponding image decoding method is provided.

Abstract: An encoding method includes following steps: performing a wave-front parallel encoding procedure for encoding pixel data of a frame partition, wherein the frame partition comprises a plurality of block rows, each of the block rows comprises a plurality of blocks, and each of the blocks comprises a plurality of pixels; and imposing constraint on a coding mode selection of a first block of a first block row.

Abstract: An image compression method includes at least the following steps: receiving a plurality of pixels of a frame, wherein pixel data of each pixel has a plurality of color channel data corresponding to a plurality of different color channels, respectively; encoding the pixel data of each pixel and generating bit-streams corresponding to the plurality of color channel data of the pixel, wherein the bit-streams corresponding to the plurality of color channel data of the pixel are separated; packing bit-streams of a same color channel data of different pixels into color channel bit-stream segments, wherein each of the bit-stream segments has a same predetermined size; and concatenating color channel bit-stream segments of the different color channels into a final bit-stream. Alternatively, color channel bit-stream segments of the same pixel are concatenated into a concatenated bit-stream portion, and concatenated bit-stream portions of different pixels are concatenated into a final bit-stream.

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 and apparatus for a multiple-channel image/video coding system are disclosed. A residue generation process is applied to the image/video data to generate residue data. A set of integer operations is applied to the residue data across the input channels to generate residue transformed data having multiple output channels. In one embodiment, the residue transformed data associated with a first output channel is related to the difference between a first residue data associated with a first input channel and a second residue data associated with a second input channel. In another embodiment, the residue transformed data associated with a second output channel is related to the second difference between a threshold and a third residue data associated with a third input channel, and wherein the threshold corresponds to the first truncated or rounded average of the first residue data and the second residue data.