| 摘要 |
PURPOSE:To remove a block-shaped noise to be generated in a background part attributing to the fluctuation of a light source or the like by firstly detecting the background part and preventing the differential signal between frames of the background area from being transmitted by the prevention of the encoding of the part. CONSTITUTION:A background area detection circuit 4 detects a background area block with the use of an input image frame, an input image preceding to one-encoded frame, namely an image frame being stored in a frame memory 2 and a reproduction image preceding to one-encoded frame, namely an image frame being stored in a frame memory 7 and sends out a background area instruction signal to an inter-frame prediction circuit 3 with a movement compensation and an inter-frame differential image encoding circuit 5. The prediction circuit 3 calculates the inter-frame differential image executing the movement compensation through the input image and the reproduction image preceding to one-encoded frame. In this case, the movement compensation is not executed in the background part. The encoding circuit 5 encodes the inter-frame differential image and outputs an output code and the local decoding signal of the inter-frame differential image. The background part is encoded so that the local decoding signal may turn to zero. |
