Embodiments of this application provide an image transmission method and apparatus. The method includes: converting a first high-resolution image into a first low-resolution image, where first resolution of the first high-resolution image is higher than second resolution of the first low-resolution image; encoding the first low-resolution image to obtain a first bitstream; obtaining a second high-resolution image, where third resolution of the second high-resolution image is higher than the second resolution, and the second high-resolution image includes high-frequency information of the first high-resolution image and excludes low-frequency information of the first high-resolution image; obtaining an image residual between the first high-resolution image and the second high-resolution image, where the image residual is used to reflect the low-frequency information of the first high-resolution image; encoding the image residual to obtain a second bitstream; and sending the first bitstream and the second bitstream.

Embodiments of this application provide an image transmission method and apparatus. The method includes: converting a first high-resolution image into a first low-resolution image, where first resolution of the first high-resolution image is higher than second resolution of the first low-resolution image; encoding the first low-resolution image to obtain a first bitstream; obtaining a second high-resolution image, where third resolution of the second high-resolution image is higher than the second resolution, and the second high-resolution image includes high-frequency information of the first high-resolution image and excludes low-frequency information of the first high-resolution image; obtaining an image residual between the first high-resolution image and the second high-resolution image, where the image residual is used to reflect the low-frequency information of the first high-resolution image; encoding the image residual to obtain a second bitstream; and sending the first bitstream and the second bitstream.

According to the present invention, an inter prediction method comprises the steps of: generating a merge candidate list for a block to be predicted, wherein the block is to correspond to a current prediction unit; deriving, on the basis of one of a plurality of merge candidates constituting the merge candidate list, motion information on the block to be predicted; and performing, on the basis of the derived motion information, a prediction on the block to be predicted so as to generate a prediction block corresponding to the current prediction unit.

According to the present invention, an inter prediction method comprises the steps of: generating a merge candidate list for a block to be predicted, wherein the block is to correspond to a current prediction unit; deriving, on the basis of one of a plurality of merge candidates constituting the merge candidate list, motion information on the block to be predicted; and performing, on the basis of the derived motion information, a prediction on the block to be predicted so as to generate a prediction block corresponding to the current prediction unit.

A method to be performed by a receiving apparatus for decoding an encoded bitstream representing a sequence of pictures of a video stream is provided. In the method, capabilities relating to level of decoding parallelism for the decoder are identified, a parameter indicative of the decoder's capabilities relating to level of decoding parallelism is kept, and for a set of levels of decoding parallelism, information relating to HEVC profile and HEVC level that the decoder is capable of decoding is kept. A method for encoding a bitstream representing a sequence of pictures of a video stream is also provided. In the method, a parameter is received from a transmitting apparatus that should decode the encoded bitstream.

A method to be performed by a receiving apparatus for decoding an encoded bitstream representing a sequence of pictures of a video stream is provided. In the method, capabilities relating to level of decoding parallelism for the decoder are identified, a parameter indicative of the decoder's capabilities relating to level of decoding parallelism is kept, and for a set of levels of decoding parallelism, information relating to HEVC profile and HEVC level that the decoder is capable of decoding is kept. A method for encoding a bitstream representing a sequence of pictures of a video stream is also provided. In the method, a parameter is received from a transmitting apparatus that should decode the encoded bitstream.

A decoder is configured to decode a plurality of texels from a received block of texture data encoded according to the Adaptive Scalable Texture Compression (ASTC) format, and includes a parameter decode unit configured to decode configuration data for the received block of texture data, a colour decode unit configured to decode colour endpoint data for the plurality of texels of the received block in dependence on the configuration data, a weight decode unit configured to decode interpolation weight data for each of the plurality of texels of the received block in dependence on the configuration data, and at least one interpolator unit configured to calculate a colour value for each of the plurality of texels of the received block using the interpolation weight data for that texel and a pair of colour endpoints from the colour endpoint data. At least one of the parameter decode unit, colour decode unit and weight decode unit are configured to decode intermediate data from the received block that is common to the decoding of at least a subset of texels of that block and to use that decoded intermediate data as part of the decoding of at least two of the plurality of texels from the received block of texture data.

A decoder is configured to decode a plurality of texels from a received block of texture data encoded according to the Adaptive Scalable Texture Compression (ASTC) format, and includes a parameter decode unit configured to decode configuration data for the received block of texture data, a colour decode unit configured to decode colour endpoint data for the plurality of texels of the received block in dependence on the configuration data, a weight decode unit configured to decode interpolation weight data for each of the plurality of texels of the received block in dependence on the configuration data, and at least one interpolator unit configured to calculate a colour value for each of the plurality of texels of the received block using the interpolation weight data for that texel and a pair of colour endpoints from the colour endpoint data. At least one of the parameter decode unit, colour decode unit and weight decode unit are configured to decode intermediate data from the received block that is common to the decoding of at least a subset of texels of that block and to use that decoded intermediate data as part of the decoding of at least two of the plurality of texels from the received block of texture data.

Techniques for lossless compression of a digital image using prior image context.

Methods, systems, and devices for luma mapping with chroma scaling for video and image coding are disclosed. An example method of video processing includes performing, for a current region comprising a luma block, a first chroma block, and a second chroma block, a conversion between the current region of a video and a bitstream representation of the video according to a rule that specifies an order in which, during decoding, the first chroma block and the second chroma block are processed based on mapped sample values of the luma block.