Motion image encoding method and motion image decoding method
First Claim
1. A video coding method for coding an input picture on a block-by-block basis so as to generate a coded stream, said method comprising:
- determining, using a processor, a notification method for notifying a transform block size to be used in an orthogonal transform of a current block;
creating an adaptive block transform mode indicating the notification method;
generating the coded stream; and
adding the adaptive block transform mode to the coded stream;
wherein said determining includes determining, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, andwherein in the implicit mode, the transform block size is determined based on motion vectors of blocks adjacent to the current block.
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Accused Products
Abstract
The present invention provides a video coding method and a video decoding method which allow enhancement of coding efficiency and improvement in video quality. A video coding apparatus includes: a mode determination unit which determines a notification method for notifying a transform block size to be used in orthogonal transform of a current block to be either the implicit mode or the explicit mode, and outputs the ABT mode indicating the determined notification method; an orthogonal transformation unit which transforms the difference values between the input image and predicted image into frequency coefficients based on the transform block size determined in accordance with the determined notification method; a quantization unit which quantizes the frequency coefficients and output the quantized values; and a variable length coding unit which performs variable length coding on the quantized values, the ABT mode, and the like, so as to output a coded stream.
25 Citations
19 Claims
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1. A video coding method for coding an input picture on a block-by-block basis so as to generate a coded stream, said method comprising:
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determining, using a processor, a notification method for notifying a transform block size to be used in an orthogonal transform of a current block; creating an adaptive block transform mode indicating the notification method; generating the coded stream; and adding the adaptive block transform mode to the coded stream; wherein said determining includes determining, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on motion vectors of blocks adjacent to the current block. - View Dependent Claims (2, 5, 6)
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3. A video coding method for coding an input picture on a block-by-block basis so as to generate a coded stream, said method comprising:
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determining, using a processor, a notification method for notifying a transform block size to be used in an orthogonal transform of a current block; creating an adaptive block transform mode indicating the notification method; generating the coded stream; and adding the adaptive block transform mode to the coded stream; wherein said determining includes determining, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on a quantization step used for quantization of the current block. - View Dependent Claims (4)
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7. A video decoding method for decoding a coded stream on a block-by-block basis, said method comprising:
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obtaining, from the coded stream, an adaptive block transform mode indicating a notification method for notifying a transform block size used in an orthogonal transform of a current block; identifying the notification method based on the adaptive block transform mode; determining, using a processor, the transform block size based on the identified notification method; and decoding the current block by performing an inverse orthogonal transform on the current block using the determined transform block size, wherein the adaptive block transform mode indicates, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on motion vectors of blocks adjacent to the current block. - View Dependent Claims (8, 11)
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9. A video decoding method for decoding a coded stream on a block-by-block basis, said method comprising:
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obtaining, from the coded stream, an adaptive block transform mode indicating a notification method for notifying a transform block size used in an orthogonal transform of a current block; identifying the notification method based on the adaptive block transform mode; determining, using a processor, the transform block size based on the identified notification method; and decoding the current block by performing an inverse orthogonal transform on the current block using the determined transform block size, wherein the adaptive block transform mode indicates, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on a quantization step used for quantization of the current block. - View Dependent Claims (10)
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12. A video coding apparatus which codes an input picture on a block-by-block basis so as to generate a coded stream, said apparatus comprising:
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a processor; a notification method determination unit operable to determine, using said processor, a notification method for notifying a transform block size to be used in an orthogonal transform of a current block; a creation unit operable to create an adaptive block transform mode indicating the notification method; and a coding unit operable to generate the coded stream and add the adaptive block transform mode to the coded stream, wherein said notification method determination unit is operable to determine, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on motion vectors of blocks adjacent to the current block.
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13. A video decoding apparatus which decodes a coded stream on a block-by-block basis, said apparatus comprising:
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a processor; an obtaining unit operable to obtain, from the coded stream, an adaptive block transform mode indicating a notification method for notifying a transform block size used in an orthogonal transform of a current block; an identification unit operable to identify the notification method based on the adaptive block transform mode; a determination unit operable to determine, using said processor, the transform block size based on the identified notification method; and a decoding unit operable to decode the current block by performing an inverse orthogonal transform on the current block using the determined transform block size, wherein the adaptive block transform mode indicates, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on motion vectors of blocks adjacent to the current block.
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14. An integrated circuit for coding an input picture on a block-by-block basis so as to generate a coded stream, said circuit comprising:
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a processor; a notification method determination unit operable to determine, using said processor, a notification method for notifying a transform block size to be used in an orthogonal transform of a current block; a creation unit operable to create an adaptive block transform mode indicating the notification method; and a coding unit operable to generate the coded stream and add the adaptive block transform mode to the coded stream, wherein said notification method determination unit is operable to determine, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on motion vectors of blocks adjacent to the current block.
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15. An integrated circuit for decoding a coded stream on a block-by-block basis, said circuit comprising:
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a processor; an obtaining unit operable to obtain, from the coded stream, an adaptive block transform mode indicating a notification method for notifying a transform block size used in an orthogonal transform of a current block; an identification unit operable to identify the notification method based on the adaptive block transform mode; a determination unit operable to determine, using said processor, the transform block size based on the identified notification method; and a decoding unit operable to decode the current block by performing an inverse orthogonal transform on the current block using the determined transform block size, wherein the adaptive block transform mode indicates, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on motion vectors of blocks adjacent to the current block.
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16. A video coding apparatus which codes an input picture on a block-by-block basis so as to generate a coded stream, said video coding apparatus comprising:
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a processor; a notification method determination unit operable to determine, using said processor, a notification method for notifying a transform block size to be used in an orthogonal transform of a current block; a creation unit operable to create an adaptive block transform mode indicating the notification method; and a coding unit operable to generate the coded stream and add the adaptive block transform mode to the coded stream, wherein said notification method determination unit is operable to determine, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on a quantization step used for quantization of the current block.
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17. A video decoding apparatus which decodes a coded stream on a block-by-block basis, said apparatus comprising:
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a processor; an obtaining unit operable to obtain, from the coded stream, an adaptive block transform mode indicating a notification method for notifying a transform block size used in an orthogonal transform of a current block; an identification unit operable to identify the notification method based on the adaptive block transform mode; a determination unit operable to determine, using said processor, the transform block size based on the identified notification method; and a decoding unit operable to decode the current block by performing an inverse orthogonal transform on the current block using the determined transform block size, wherein the adaptive block transform mode indicates, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on a quantization step used for quantization of the current block.
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18. An integrated circuit for coding an input picture on a block-by-block basis so as to generate a coded stream, said circuit comprising:
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a processor; a notification method determination unit operable to determine, using said processor, a notification method for notifying a transform block size to be used in an orthogonal transform of a current block; a creation unit operable to create an adaptive block transform mode indicating the notification method; and a coding unit operable to generate the coded stream and add the adaptive block transform mode to the coded stream, wherein said notification method determination unit is operable to determine, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on a quantization step used for quantization of the current block.
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19. An integrated circuit for decoding a coded stream on a block-by-block basis, said circuit comprising:
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a processor; an obtaining unit operable to obtain, from the coded stream, an adaptive block transform mode indicating a notification method for notifying a transform block size used in an orthogonal transform of a current block; an identification unit operable to identify the notification method based on the adaptive block transform mode; a determination unit operable to determine, using said processor, the transform block size based on the identified notification method; and a decoding unit operable to decode the current block by performing an inverse orthogonal transform on the current block using the determined transform block size, wherein the adaptive block transform mode indicates, as the notification method, either (i) an implicit mode in which the transform block size is determined based on information regarding the current block or (ii) an explicit mode in which a transform size flag indicating the transform block size is added to each predetermined unit of blocks, and wherein in the implicit mode, the transform block size is determined based on a quantization step used for quantization of the current block.
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Specification