Patent ID: 9544585
Date: 2017-01-10
CPC Classifications: H04N

Claim:
1. A decoding method for decoding an image on a block-by-block basis, the decoding method comprising: determining a second quantization parameter for an Intra Pulse Code Modulation (IPCM) block using a first quantization parameter used for quantizing a non-Intra Pulse Code Modulation (non-IPCM) block, the IPCM block and the non-IPCM block being adjacent to each other in the image; determining a filter strength of deblocking filtering using an average of the first quantization parameter and the second quantization parameter; and performing the deblocking filtering on a boundary between the IPCM block and the non-IPCM block using the determined filter strength of the deblocking filtering, wherein the second quantization parameter is determined using difference information indicating a difference between a quantization parameter for a block which is located immediately before a current block to be processed in processing order and a quantization parameter for the current block, the difference information indicating a zero value.