Motion picture encoding system wherein image quality is maximized using inter-frame and intra-frame encoding

DETAILED DESCRIPTION In view of the foregoing, an object of the present invention is to provide a motion picture encoding system with high encoding efficiency and which also permits improvement of the picture quality.
To solve the above problems, according to a first aspect of the present invention there is provided a motion picture encoding system for either intra-frame encoding or inter-frame encoding a motion picture, comprising a means for setting, prior to any encoding operation, a priority order for small areas as units of encoding in a certain one of a plurality of frames to be encoded, the priority order establishing a quantization step size to be used, means for encoding the whole certain one of the plurality of frames in accordance with the priority order set for the small areas, means for detecting motion information and revising the priority order for corresponding small areas of succeeding frames in the sequence of frames according to the motion information, and a means for changing the encoding system for each predetermined portion of the motion picture according to the priority order.
In another embodiment of the invention a motion picture encoding system for either intra-frame encoding or inter-frame encoding a motion picture which includes a sequence of frames, comprises a first encoding means for encoding at least a portion of the motion picture by intra-frame encoding, a second encoding means for encoding at least a portion of the motion picture by inter-frame encoding, means for obtaining a first quantity of data from the first encoding means when it encodes a target frame using a quantization step size which was used for a preceding frame and a second quantity of data from the second encoding means when it encodes the target frame using the quantization step size which was used for a preceding frame, and means for selecting the first encoding means if the first quantity of data is less than the second quantity of data and otherwise selecting the second encoding means