Patent ID: 6907069

Claim:
A picture coding apparatus comprising: a group structure determining portion for constituting a plurality of picture frames as a group according to correlation between the picture frames in a picture sequence, the group structure determining portion for determining a coding mode corresponding to each of the picture frames of the group; a precoding portion for performing precoding according to the coding mode determined by the group structure determining portion correspondingly to each of the picture frames; a coding portion for performing coding of a picture by controlling a coding parameter according to a result of the precoding obtained by the precoding portion and to the coding mode determined by the group structure determining portion; and a scene change detecting portion for evaluating correlation between the picture frames in the picture sequence and for detecting, when there is a part having low interframe correlation, the part as a scene change part, wherein the group structure determining portion sets the plurality of picture frames as the group according to the detected scene change part; wherein the scene change detecting portion performs a forward motion compensation interframe prediction and a backward motion compensation interframe prediction on each frame of an input picture sequence having a plurality of frames to detect a scene change by evaluating results of both the forward and backward predictions.