IMAGE ENCODER, IMAGE ENCODING METHOD AND PROGRAM, AND IMAGE DECODER, IMAGE DECODING METHOD AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide an image encoder and an image decoder capable of performing encoding and decoding using proper quantization parameters with respect to palette encoding and escape encoding, and non-palette encoding (predictive encoding).SOLUTION: An image decoder which decodes encoded image data comprises: input means for inputting code data encoded in block units; acquiring means for acquiring quantization parameters of a block to be decoded from the code data; first determining means for determining whether the block to be decoded from the code data is in a predictive encoding or palette encoding state; and decoding means for decoding a quantized conversion coefficient corresponding to the block to be decoded according to a result of the first determining means, i.e. when the block to be decoded is in the predictive encoding state.SELECTED DRAWING: Figure 1