These techniques have been utilized by some proprietary
These techniques have been utilized by some proprietary streaming codecs, again to improve video quality within the constraints of the average channel bandwidth. The codecs use the server and player buffers to average the data, so that a continuous bandwidth is transmitted across the IP connection. Figure 8.8 shows two streams, one constant and one variable, used across the same fixed bandwidth channel. Note that, during the action scenes, the VBR channel has an increased bit rate. The CBR channel will have a lower quality during these scenes. Again, like DVD encoding, two-pass encodes give better results with VBR. The first pass analyzes the entire video file to find the best encode rates. The second pass is the true encode and uses the data gathered from the first pass. Obviously this technique can be used only when encoding a video file, rather than a live stream. 172 The Technology of Video and Audio Streaming encoder fixed bandwidth circuit compress buffer streaming server buffer decompress media player video VBR file VBR file video Figure 8.7 Variable bit buffering. lower mean bit rate time bit rate quality gap action scene action scene VBR CBR Figure 8.8 Variable and constant bit rates.
Note: If you are looking for good and high quality web space to host and run your application check Lunarwebhost Cheap Web Hosting services