Image processing apparatus and method of encoding image data therefor

An image processing apparatus for encoding and decoding image data in which a still picture frame of an image quality higher than a prescribed imaging quality is mixed in moving picture data composed of successive moving picture frames having the prescribed imaging quality, comprising:

• first encoding means for encoding the moving picture frames in the moving picture data and, with regard to the still picture frame in the moving picture data, generating moving picture part data, which has a quality equivalent to that of moving picture frames, from the still picture frame and encoding the moving picture part data, thereby generating moving picture encoded data;
• second encoding means for encoding difference data, the difference data being the result of removing the moving picture part data from the still picture frame;
• additional-information generating means for generating correspondence information and identification information, the correspondence information correlating the moving picture part data and corresponding difference data, and the identification information specifying the moving picture part data contained in the moving picture encoded data;
• recording means for recording, on a storage medium, the moving picture frame encoded data, the difference encoded data, the correspondence information and the identification information as result of encoding the moving picture data;
• a reproducing means for selectively reproducing the moving picture frames or the still image frame based on the encoding result recorded on the storage medium;
• and
• a decoding means for, when the reproducing means reproduces the still image frame, decoding only the moving picture part data specified by the identification information from all of the moving picture part data included in the moving picture frame encoded data and displaying the decoded image, wherein the decoding means further decodes, upon designated the decoded image by a user, based on the corresponding information, the difference encoded data corresponding to the moving picture part data associated with the designated decoded image and displays the decoded image.