| 摘要 |
<p>The invention concerns the control of Asynchronous Transfer Mode (ATM), or other systems, using available bit rate (ABR) transmission. A source of data is permitted to transmit at a data rate which is set by the network according to the available capacity. Where television pictures are being transmitted, the actual data rate can be controlled by varying the degree of compression applied by video coder (or transcoder). Existing procedures for dividing up the available capacity between competing video sources are found to be unsatisfactory in terms of achieving equal picture quality for each source. In the invention, each source calculates a measure of picture complexity, and the network (for example, an ATM switch) uses the means to calculate how the capacity should be shared.</p> |
