| 摘要 |
<p>In an MPEG-2 decoder unit (2), a variable length decoding unit (2A) analyzes syntax of input compressed data (1) according to the MPEG-2 standard and generates coding mode information (3), motion vector information (4), and a prediction residual signal (2B). The prediction residual signal (2B) goes through a dequantization unit (2C) and becomes decoding image (5), which is supplied via a resolution conversion unit (6) to an MPEG-4 encoder unit (10). IN the MPEG-4 encoder unit (10), a coding parameter judgment unit (10B) decides a motion vector according to a prediction error evaluation value evaluating a prediction efficiency when a motion vector candidate generated by a motion vector mapping unit (7) is used and a value evaluating the motion vector coding amount when the motion vector candidate is used.</p> |
