| 摘要 |
<p>PURPOSE:To set an encode processing speed at a speed fitted for a transmission capacity, and to reduce a device in scale by providing a memory possible to store a picture of one field, at least, or more at the input front stage of an encoder, and performing a speed change. CONSTITUTION:An input video signal 1 is inputted to a pre-frame memory 12 synchronizing with a video clock, and the pre-frame memory 12 sends out an input video signal 13 to an encoding circuit 15 synchronizing with a transmission line clock. The encoding circuit 15 performs, based on an encoding parameter 14, an inter-frame encoding, or in-frame encoding only on an effective picture element between a past video signal 19 encoded already at the previous time and read out from an encoding frame memory 20 and the input video signal 13, and an encoding data 16 and a local decoding signal 22 are outputted. The encoding circuit 15 does not perform a real time operation, but performs an encoding process synchronizing with a processing speed corresponding to the capacity of a transmission line 9, that is, the transmission line clock. In other words, the encoding data 16 is multiplexed with a bit of encoding control information 7 at a multiplexing circuit 8, then being sent out to the transmission line 9.</p> |
