| 摘要 |
In a video signal processor including a motion compensated predictive coding data compression system, three adjacent image frames (1, 2, 3) are analyzed to detect a luminance gradient such as is typically associated with image fading. The frames are similarly divided into several segments (A...L). The sum of the absolute pixel value differences between corresponding segments from adjacent frames is obtained for each of two pairs of adjacent frame segments (DIFF1-2; DIFF2-3). The ratio of the two frame differences (S) is obtained for each segment. Fading is indicated if the ratio remains substantially constant for all or a predetermined number of regions. If fading is detected, any motion vectors generated by the motion coder are assigned a zero value and are not coded. <IMAGE> |
