| 摘要 |
<p>PROBLEM TO BE SOLVED: To eliminate the need for a background memory and a subblock division circuit, to simplify circuit constitution and to improve the characteristics/performance of the image encoder by dividing a video signal into plural blocks, comparing each block with its corresponding threshold, setting up the block as a still area when the block is less than the threshold or as a moving area, when the block is more than the threshold as the compared result and stopping encoding in the still area or encoding an image at high resolution in the moving area. SOLUTION: A delay circuit (mD) 131, to which image data are inputted from a preprocessing part, applies a delay of processing time to be required for the detection of a moving vector by a moving vector detection part 143. A subtractor 132 finds out the difference between the image data of a current frame from the mD 131 and the image data of a preceding frame outputted from a frame memory(FM) 141 by a subtracter and inputs the difference value to a DCT 133 and a comparator 135. The comparator 135 compares the difference value with a theshold separated from a DMUX or set up in a self-station side image transmitter, and wen the difference value is less than the threshold as the compared result, detects the image data as a still area. When the difference value is larger than the threshold, the data are detected as a moving area.</p> |
