 | 1 | initial version |
They thing you need to be aware of is that media playback depends not only on the audio samples, but on the timely availability of these samples. Saving the audio samples in a WAV file and playing them back provides all samples to the media player at the same time. Therefore the media player never runs out of samples to play and the audio is 'smooth', as in, not interrupted by missing audio samples.
Now if you look at RTP this is not necessarily the case. The network packets may come in delayed, causing the RTP player to miss the samples it needs to play. This is where the jitter buffer comes in to help out. It gives some leeway in the arrival time of RTP packets and provides for a smooth, all be it delayed, playback.
This delayed playback may not be an issue, but quickly becomes one if for instance it stretches beyond 150 ms in a phone call.
| | 2 | No.2 Revision |
They The thing you need to be aware of is that media playback depends not only on the audio samples, but on the timely availability of these samples. Saving the audio samples in a WAV file and playing them back provides all samples to the media player at the same time. Therefore the media player never runs out of samples to play and the audio is 'smooth', as in, not interrupted by missing audio samples.
Now if you look at RTP this is not necessarily the case. The network packets may come in delayed, causing the RTP player to miss the samples it needs to play. This is where the jitter buffer comes in to help out. It gives some leeway in the arrival time of RTP packets and provides for a smooth, all be it albeit delayed, playback.
This delayed playback may not be an issue, but quickly becomes one if for instance it stretches beyond 150 ms in a phone call.
