摘要:
A coding method according to the present invention comprises: transforming an input signal to generate a transformed output signal; quantizing the transformed output signal to generate quantized coefficients; and entropy coding the quantized coefficients to generate a coded signal, wherein the transforming includes: generating a first transformed output signal by performing a first transform on the input signal using a first transform coefficient; and generating a second transformed output signal by performing, using a second transform coefficient, a second transform on a first partial signal which is a part of the first transformed output signal, and outputting the transformed output signal including (i) the generated second transformed output signal and (ii) a second partial signal which is the remaining part of the first transformed output signal other than the first partial signal.
摘要:
A coding method according to the present invention comprises: transforming an input signal; quantizing a transformed output signal; and entropy coding quantized coefficients, wherein the transforming includes: generating a first transformed output signal by performing a first transform on the input signal using a first transform coefficient; generating a second transformed output signal by performing, using a second transform coefficient, a second transform on a first partial signal which is a part of the first transformed output signal, and outputting the transformed output signal including the generated second transformed output signal and a second partial signal which is the remaining part of the first transformed output signal other than the first partial signal; and modifying the first transformed output signal.
摘要:
The coding method includes: transforming pixel values of an image into a two-dimensional matrix including N coefficients in a frequency domain; quantizing the N coefficients to generate N quantized coefficients; generating a one-dimensional sequence based on the two-dimensional matrix and tree structure information that defines a binary tree; and coding the one-dimensional sequence and at least some of the N quantized coefficients. The generating includes: determining, based on the two-dimensional matrix, a reference destination information item indicating positions of the N quantized coefficients in the two-dimensional matrix to be referenced to by the N leaf nodes, respectively (S31); assigning one of a first value and a second value to each of the nodes of the binary tree, based on the two-dimensional matrix and the reference destination information item (S32); and arranging, in preorder, the values assigned to the respective nodes to generate the one-dimensional sequence (S33).
摘要:
A coding method comprises: transforming an input signal; scanning and quantizing coefficient values composing the transformed output signal; and entropy coding the quantized coefficients, wherein the transforming includes: generating a first transformed output signal by performing a first transform on the input signal using a first transform coefficient; and generating a second transformed output signal by performing, using a second transform coefficient, a second transform on a first partial signal which is a part of the first transformed output signal, and outputting the transformed output signal including the generated second transformed output signal and a second partial signal that is the remaining part of the first transformed output signal other than the first partial signal, and a signal corresponding to the second transformed output signal and a signal corresponding to the second partial signal are processed differently in at least one of the scanning, the quantizing, and the entropy coding.
摘要:
A coding method according to an implementation of the present invention includes: transforming an input signal using a first transform coefficient (S110); transforming, using a second transform coefficient, a first partial signal that is a part of the first transformed output signal (S130b); quantizing the second transformed output signal and a second partial signal that is a part of the first transformed output signal other than the first partial signal (S150b); and entropy coding the quantized coefficient (S160), and the transforming of a first partial signal (S130b) includes: modifying the first partial signal or the second transform coefficient using a predetermined scaling parameter to generate a modified first partial signal or a modified second transform coefficient (S131); and generating the second transformed output signal (S132) by transforming the modified first partial signal using the second transform coefficient or transforming the first partial signal using the modified second transform coefficient.
摘要:
A coding method comprises: transforming an input signal; quantizing a transformed output signal; and entropy coding quantized coefficients, wherein the transforming includes: generating a first transformed output signal by performing a first transform on the input signal using a first transform coefficient; and generating a second transformed output signal by performing, using a second transform coefficient, a second transform on a first partial signal which is a part of the first transformed output signal, and outputting the transformed output signal including the generated second transformed output signal and a second partial signal which is the remaining part of the first transformed output signal other than the first partial signal, and wherein, in the generating and outputting, at least one of (i) the first partial signal that is a target signal range for the second transform and (ii) the second transform coefficient is adaptively determined temporally or spatially.
摘要:
A spatial prediction method capable of reducing the complexity of spatial prediction includes: detecting an edge (E) overlapping the current block by obtaining a horizontal gradient (Gy) and a vertical gradient (Gx) between pixels within a block adjacent to the current block; calculating an integer slope of the edge; determining, for each pixel position within the current block, a sub-pel position being an intersection between (i) a line that has the integer slope and passes through the pixel position and (ii) a boundary of the adjacent block; and predicting, for each pixel position, a pixel value at the pixel position based on a pixel value interpolated in the sub-pel position, wherein the boundary of the adjacent block is a row or a column that is the closest to the current block, among rows or columns of pixels included in the adjacent block.
摘要:
A spatial prediction method capable of reducing the complexity of spatial prediction includes: detecting an edge (E) overlapping the current block by obtaining a horizontal gradient (Gy) and a vertical gradient (Gx) between pixels within a block adjacent to the current block; calculating an integer slope of the edge; determining, for each pixel position within the current block, a sub-pel position being an intersection between (i) a line that has the integer slope and passes through the pixel position and (ii) a boundary of the adjacent block; and predicting, for each pixel position, a pixel value at the pixel position based on a pixel value interpolated in the sub-pel position, wherein the boundary of the adjacent block is a row or a column that is the closest to the current block, among rows or columns of pixels included in the adjacent block.
摘要:
An image decoding method includes: restoring a selected prediction mode used in prediction at a time of coding; and decoding a current block included in coded image data to generate a decoded block, according to the prediction based on the selected prediction mode. The restoring includes: determining a first estimated prediction mode; determining a second estimated prediction mode different from the first estimated prediction mode; and restoring the selected prediction mode based on the mode information, the first estimated prediction mode, and the second estimated prediction mode.
摘要:
In order to achieve higher coding efficiency, suppress coding artifacts, and not to need a large computing amount, an image and video data are coded. Provided is an image coding method of coding image data on a block-by-block basis, and the method includes: coding a current block according to a prediction based on a selected prediction mode (S101); determining an estimated prediction mode from among candidate prediction modes; and outputting the coded current block and mode information for reconstructing the selected prediction mode (S108). The determining includes: detecting an edge (S103); reducing the candidate prediction modes in number based on the detected edge (S105); determining the estimated prediction mode from among the candidate prediction modes reduced in number (S106); and generating the mode information based on the estimated prediction mode and the selected prediction mode (S107).