Image coding device and method, and image decoding device and method

The invention provides an image coding device, including a development module, a quantification module and a coding module. The development module selects one target development mode from multiple development modes for one to-be-coded image, and develops a coefficient matrix into a quantification table according to the target expansion mode. The quantification module applies a quantification program to an image data matrix of the to-be-coded image according to the quantification table, so as to generate a quantification result. The coding module codes the quantification result to generate a coding result, and writes an identification message of the target development mode into the coding result.