Abstract: The present invention relates to an image compression method and apparatus, where the image compression method includes a step of performing amplitude decreasing processing on a frequency domain coefficient or a quantization coefficient of a to-be-processed image. The image compression method includes: determining a texture direction of the to-be-processed image; and performing amplitude decreasing processing on the frequency domain coefficient or the quantization coefficient of the to-be-processed image according to the texture direction, where the frequency domain coefficient is a coefficient obtained after the image is transformed, and the quantization coefficient is a coefficient obtained after the frequency domain coefficient is quantized.

Abstract: Embodiments of the present invention provide an encoding or decoding method and apparatus. The method includes: extracting first information in a bitstream; determining a chroma component intra prediction mode according to the first information; when the chroma component intra prediction mode cannot be determined according to the first information, extracting second information in the bitstream; and determining the chroma component intra prediction mode according to the second information, where the first information includes information for indicating whether the chroma component intra prediction mode is a DM mode or an LM mode, the second information is used to indicate a remaining mode as the chroma component intra prediction mode, and the remaining mode is one of available chroma component intra prediction modes other than a mode that may be determined according to the first information.

Abstract: Embodiments of the present invention provide an encoding or decoding method and apparatus. The method includes: extracting first information in a bitstream; determining a chroma component intra prediction mode according to the first information; when the chroma component intra prediction mode cannot be determined according to the first information, extracting second information in the bitstream; and determining the chroma component intra prediction mode according to the second information, where the first information includes information for indicating whether the chroma component intra prediction mode is a DM mode or an LM mode, the second information is used to indicate a remaining mode as the chroma component intra prediction mode, and the remaining mode is one of available chroma component intra prediction modes other than a mode that may be determined according to the first information.

Abstract: An embodiment of the present invention provides an image coding method, where the coding method includes: performing predictive coding on an image; performing transform coding on the image on which the predictive coding has been performed; performing, by using a quantization matrix, quantization coding on the image on which the transform coding has been performed, where the quantization matrix is a matrix reflecting image quantization step information, the quantization matrix includes an M*N quantization matrix and an N*M quantization matrix, and the N*M quantization matrix is obtained by transposing the M*N quantization matrix; and performing entropy coding on the image on which the quantization coding has been performed, and coding the M*N quantization matrix, so as to generate a code stream. In the present invention, the number of bits required for coding a quantization matrix is effectively saved, thereby improving compression efficiency.

Abstract: Embodiments of the present invention provide an intra-frame decoding method and apparatus for a signal component sampling point of an image block. The method includes: obtaining prediction mode information about a first signal component of a current block from a video code stream; determining a prediction mode for the first signal component of the current block, where the prediction mode for the first signal component of the current block is one of a DM mode and an LM mode; obtaining a prediction value of a first signal component sampling point of the current block according to the prediction mode for the first signal component of the current block; and obtaining a reconstruction value of the first signal component sampling point of the current block. The technical solutions provided by the embodiments of the present invention reduce complexity of implementing a decoding end.

Abstract: An embodiment of the present invention provides an image coding method, where the coding method includes: performing predictive coding on an image; performing transform coding on the image on which the predictive coding has been performed; performing, by using a quantization matrix, quantization coding on the image on which the transform coding has been performed, where the quantization matrix is a matrix reflecting image quantization step information, the quantization matrix includes an M*N quantization matrix and an N*M quantization matrix, and the N*M quantization matrix is obtained by transposing the M*N quantization matrix; and performing entropy coding on the image on which the quantization coding has been performed, and coding the M*N quantization matrix, so as to generate a code stream. In the present invention, the number of bits required for coding a quantization matrix is effectively saved, thereby improving compression efficiency.

Abstract: The present invention relates to a method for coding and decoding a video signal, and provides a method for coding a video signal, including: determining space adjacent motion information of a parallel motion processing region PR; determining time adjacent motion information of a current block, where the current block is located in the parallel motion processing region PR; determining a candidate mot ion information set according to the space adjacent motion information of the parallel motion processing region PR and the time adjacent motion information of the current block; selecting motion information of the current block from the candidate motion information set, and sending a motion information indication of the current block to a decoding end, so as to assist the decoding end in determining the motion information of the current block; and performing motion compensation coding for the current block according to the motion information of the current block.

Abstract: Embodiments of the present invention provide an encoding or decoding method and apparatus. The method includes: extracting first information in a bitstream; determining a chroma component intra prediction mode according to the first information; when the chroma component intra prediction mode cannot be determined according to the first information, extracting second information in the bitstream; and determining the chroma component intra prediction mode according to the second information, where the first information includes information for indicating whether the chroma component intra prediction mode is a DM mode or an LM mode, the second information is used to indicate a remaining mode as the chroma component intra prediction mode, and the remaining mode is one of available chroma component intra prediction modes other than a mode that may be determined according to the first information.

Abstract: An intra-frame decoding method includes obtaining, from a video code stream, prediction mode information of a first signal component of a current block; determining a prediction mode of the first signal component of the current block from a prediction mode set of the first signal component of the current block according to the prediction mode information of the first signal component of the current block, where the prediction mode set of the first signal component of the current block includes at least one of a linear model above (LMA) mode and a linear model left (LML) mode; obtaining a predicted value of a first signal component sampling point of the current block; and obtaining a reconstructed value of the first signal component sampling point of the current block according to the predicted value of the first signal component sampling point of the current block.

Abstract: The present disclosure provides a method and an apparatus for rounding a coordinate value of a non-integer pixel position motion vector. The method includes: rounding a coordinate value of a non-integer pixel position motion vector, which includes: for each dimension of coordinates of the non-integer pixel position motion vector, when a coordinate in the dimension is a non-integer pixel position, rounding the coordinate value of the non-integer pixel position motion vector in the dimension to one of integer pixel coordinate positions A and B if distances from the coordinate of the non-integer pixel position motion vector in the dimension to the integer pixel coordinate positions A and B adjacent to the non-integer pixel position in the dimension are the same, where an integer pixel coordinate position is determined by a sign of the coordinate value of the non-integer pixel position motion vector in the dimension.

Abstract: Embodiments of the present invention provide an encoding or decoding method and apparatus. The method includes: extracting first information in a bitstream; determining a chroma component intra prediction mode according to the first information; when the chroma component intra prediction mode cannot be determined according to the first information, extracting second information in the bitstream; and determining the chroma component intra prediction mode according to the second information, where the first information includes information for indicating whether the chroma component intra prediction mode is a DM mode or an LM mode, the second information is used to indicate a remaining mode as the chroma component intra prediction mode, and the remaining mode is one of available chroma component intra prediction modes other than a mode that may be determined according to the first information.

Abstract: Embodiments of the present invention disclose a method and an apparatus for acquiring a video bitstream, and relate to the field of information technologies, which can improve network bandwidth utilization. The method includes: firstly, acquiring, by a terminal, a minimum bit rate corresponding to a parameter of the terminal; then, sending, by the terminal, a video bitstream acquiring request to a server, and when receiving the video bitstream acquiring request sent by the terminal, sending, by the server, an MPD to the terminal; and finally, receiving, by the terminal, the MPD sent by the server, and acquiring a video bitstream according to the MPD and the minimum bit rate. The embodiments of the present invention are applicable to a case in which a user downloads video data by using a terminal.

Abstract: An intra-frame decoding method is provided. The method includes: obtaining, from a video code stream, prediction mode information of a first signal component of a current block; determining a prediction mode of the first signal component of the current block from a prediction mode set of the first signal component of the current block according to the prediction mode information of the first signal component of the current block, where the prediction mode set of the first signal component of the current block includes at least one of a linear model above (LMA) mode and a linear model left (LML) mode; obtaining a predicted value of a first signal component sampling point of the current block; and obtaining a reconstructed value of the first signal component sampling point of the current block according to the predicted value of the first signal component sampling point of the current block.

Abstract: Embodiments of the present invention disclose a transformation mode encoding and decoding method and apparatus. A correlation between the prediction mode and the transformation mode is used, and an optimal transformation mode candidate set is simplified, thereby saving resources when an index of an optimal transformation mode is encoded in encoding header information. In addition, encoding efficiency is higher when an encoding end elects a transformation mode.

Abstract: The present invention relates to an image compression method and apparatus, where the image compression method includes a step of performing amplitude decreasing processing on a frequency domain coefficient or a quantization coefficient of a to-be-processed image. The image compression method includes: determining a texture direction of the to-be-processed image; and performing amplitude decreasing processing on the frequency domain coefficient or the quantization coefficient of the to-be-processed image according to the texture direction, where the frequency domain coefficient is a coefficient obtained after the image is transformed, and the quantization coefficient is a coefficient obtained after the frequency domain coefficient is quantized.

Abstract: A method and device for generating a predicted value of image that are mostly used to generate a predicted value of a current block during image encoding or decoding. The method includes: determining a searching scope, wherein multiple motion vectors are included in the searching scope; performing up-sampling interpolations on first reference blocks, corresponding to the motion vector in the searching scope, in a reference image of the current block by using a first filter to obtain up-sampled first reference blocks; by using the up-sampled first reference blocks, obtaining at least one candidate motion vector corresponding to the current block; performing up-sampling interpolations on second reference blocks, corresponding to the at least one candidate motion vector, in the reference image of the current block by using a second filter to obtain up-sampled second reference blocks; combining the up-sampled second reference blocks to obtain a predicted value of the current block.

Abstract: Embodiments of the present invention provide an encoding or decoding method and apparatus. The method includes: extracting first information in a bitstream; determining a chroma component intra prediction mode according to the first information; when the chroma component intra prediction mode cannot be determined according to the first information, extracting second information in the bitstream; and determining the chroma component intra prediction mode according to the second information, where the first information includes information for indicating whether the chroma component intra prediction mode is a DM mode or an LM mode, the second information is used to indicate a remaining mode as the chroma component intra prediction mode, and the remaining mode is one of available chroma component intra prediction modes other than a mode that may be determined according to the first information.

Abstract: A method and device for generating a predicted value of image that are mostly used to generate a predicted value of a current block during image encoding or decoding. The method includes: determining a searching scope, wherein multiple motion vectors are included in the searching scope; performing up-sampling interpolations on first reference blocks, corresponding to the motion vector in the searching scope, in a reference image of the current block by using a first filter to obtain up-sampled first reference blocks; by using the up-sampled first reference blocks, obtaining at least one candidate motion vector corresponding to the current block; performing up-sampling interpolations on second reference blocks, corresponding to the at least one candidate motion vector, in the reference image of the current block by using a second filter to obtain up-sampled second reference blocks; combining the up-sampled second reference blocks to obtain a predicted value of the current block.

Abstract: Embodiments of the present invention provide an encoding or decoding method and apparatus. The method includes: extracting first information in a bitstream; determining a chroma component intra prediction mode according to the first information; when the chroma component intra prediction mode cannot be determined according to the first information, extracting second information in the bitstream; and determining the chroma component intra prediction mode according to the second information, where the first information includes information for indicating whether the chroma component intra prediction mode is a DM mode or an LM mode, the second information is used to indicate a remaining mode as the chroma component intra prediction mode, and the remaining mode is one of available chroma component intra prediction modes other than a mode that may be determined according to the first information.

Abstract: Embodiments of the present invention provide a motion prediction or compensation method during a video coding and decoding process. A motion prediction or compensation method provided in the embodiments of the present invention includes: acquiring a candidate motion vector set; conducting a refined search for an optimal motion vector based on information of the candidate motion vector set; and performing motion prediction or compensation by using the motion vector acquired by the refined search. This improves coding performance and meanwhile maintains reasonable complexity.