Canon Kabushiki Kaisha

Masato Shima

Mitsuru Maeda

Koji Okawa

Osamu Kawaguchi

Yuji Omori

Hideaki Hattori

An orthogonal transform unit orthogonally transforms prediction residuals in a block of a P×Q array of pixels, thereby generating an N×M (N is an integer satisfying N<P, and M is an integer satisfying M<Q) array of orthogonal transform coefficients. A quantization unit quantizes the N×M array of the orthogonal transform coefficients using at least a quantization matrix of an N×M array of elements, and thereby generates an N×M array of quantized coefficients.

Image coding apparatus, image coding method, and storage media

An image decoding apparatus comprises a decoder which decodes data indicating a plurality of values corresponding to a part of a quantization matrix; a generator which derives the plurality of values from the data and generates the matrix; and an inverse quantizing unit which performs the inverse quantizing on an object block using the matrix, wherein, if width or height of the matrix is larger than or equal to a predetermined size, the generating unit generates the matrix by associating a first value among the plurality of values with a first element corresponding to DC component in the matrix, associating a second value with a second element adjacent to the first element, and, for the elements other than the first and second elements, associating each of one or more values with a plurality of elements of the matrix.

Image encoding apparatus, image decoding apparatus, control methods and non-transitory computer-readable storage medium

An encoding device, if it is determined that a transforming processing is applied to a block to be encoded, encodes the block using a first quantization parameter, if it is determined that the transforming processing is not applied to the block and the first quantization parameter is less than a reference value, encodes the block using the reference value as a quantization parameter, and, if it is determined that a pallet mode is applied to the block and the first quantization parameter is less than a reference value, encodes the block using the reference value as a quantization parameter for an escape value, wherein the reference value used if it is determined that the transforming processing is not applied to the block and the reference value used for the escape value are the same.

Image encoding device, image encoding method, and program, image decoding device, image decoding method, and non-transitory computer-readable storage medium

In prediction, one of a first mode for deriving, using pixels in an image including a target block, predicted pixels in the target block, a second mode for deriving the predicted pixels in the target block using pixels in an image different from the image including the target block, a third mode for generating the predicted pixels in the target block using both the pixels in the image including the target block and pixels in the different image can be used. If the third mode is used in at least one of the first and second blocks, the intensity of deblocking filter to be performed for the boundary between the first and second blocks is set to the same intensity as in a case in which the first mode is used in at least one of the first and second blocks.

Image encoding apparatus, image encoding method, image decoding apparatus, image decoding method, and non-transitory computer-readable storage medium

An image is divided into rectangular regions each including at least one block row, and the image is divided into rectangular slices or slices to be processed in raster order. In a case where the image is divided into the rectangular slices, based on first information for specifying a rectangular region to be processed first and second information for specifying a rectangular region to be processed last, the rectangular regions in the rectangular slice is specified. Based on the number of blocks in a vertical direction in each of the specified rectangular regions, the number of pieces of information for specifying a start position of coded data of the block row in the rectangular slice is specified. A bitstream in which at least the pieces of information, the first and second information, and the coded data are multiplexed is generated.

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Tokyo, Japan

Masato Shima