Image decoding device, image encoding device, and method thereof
AssigneeSony Corporation
InventorKenji Kondo
Life of this patent
Estimating the term…
Abstract
A lossless decoding unit 52 takes quantization parameters of decoded blocks spatially or temporally adjacent to a block to be decoded, as selection candidates, and extracts, from stream information, difference information indicating difference as to a prediction quantization parameter selected from the selection candidates. A quantization parameter calculating unit 59 calculates, from the prediction quantization parameter and the difference information, a quantization parameter of the block to be decoded. Thus, decoding of the image can be performed correctly by calculating a quantization parameter equal to a quantization parameter used at the time of image encoding.
Claims20
An image decoding method, comprising:
- obtaining, when a block adjacent to the left of a current block and a block adjacent above the current block are referenceable, a prediction quantization parameter derived from an average value of a quantization parameter of the block adjacent to the left and a quantization parameter of the block adjacent above;
- obtaining, when the block adjacent to the left and the block adjacent above are not referenceable, the prediction quantization parameter derived from a quantization parameter of a processing unit not adjacent to the current block;
- obtaining, from bit stream information, a difference information indicating a difference between the obtained prediction quantization parameter and a quantization parameter of the current block;
- and
- generating the quantization parameter of the current block, from the prediction quantization parameter and the difference information.
An information processing apparatus comprising:
- a circuitry configured to:
- obtain, when a block adjacent to the left of a current block and a block adjacent above the current block are referenceable, a prediction quantization parameter derived from an average value of a quantization parameter of the block adjacent to the left and a quantization parameter of the block adjacent above;
- obtain, when the block adjacent to the left and the block adjacent above are not referenceable, the prediction quantization parameter derived from a quantization parameter of a processing unit not adjacent to the current block;
- obtain, from bit stream information, a difference information indicating a difference between the obtained prediction quantization parameter and a quantization parameter of the current block;
- and
- generate the quantization parameter of the current block, from the prediction quantization parameter and the difference information.
Dependencies are inferred from the claim text.