TRANSCODING METHOD FOR MOVING PICTURE CODING DATA AND TRANSCODING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a transcoding device that converts coded data into coded data compatible with another coding algorithm with a small arithmetic amount while reducing the image. SOLUTION: A special IDCT section 121 applies IDCT including filter processing and pixel interleaving processing to a DCT coefficient matrix obtained from coded data to generate image data of a reduced image. A proportional reduction section 122 applies proportional reduction processing to motion information obtained from the coded data in response to an image reduction rate to generate motion information corresponding to the reduced image. A motion information estimate section 400 estimates motion information after transcoding from the motion information. A decoder 100A uses the motion information and the image data of the reduced image to generate the coded data without motion prediction.