Webinterface - Streaming
General[edit]
Streaming Conf[edit]
The activate video transcoding option allows DVBviewer to encode the video stream on the fly to video codes and datarates that are more suited to your internet connection.
To enable this, check the activate video transcoding box and then chose from the following settings:
Video codec - there are several options. Chose mpeg2 for the best compatibility, h264/mpeg4 for the best quality (this will use more CPU on the server)
Video Bitrate - this is the bitrate in bits per second for the video. If you are streaming over the internet, select a value that’s closest to your upload speed - 25% for overhead. You can choose a pre-determined bitrate from the dropdown, or you can enter a custom rate to maximise the usage of your available bandwidth. The higher the value, the better quality the picture, so you want to get the highest value that your broadband line can take.
For example, if your line has a 5mbps upload try starting off with a value of 3750 (5 x 1000 - 25%). If you start getting buffering delays / stuttering playback you will need to reduce this value. Often you will find that you will need to enter much lower values if you intend to transmit video across continent level distances as the limiting factor will be your country's link speed with the rest of the world.
Video size - this is the size of the source video - 1.00 leaves the video resolution untouched, smaller values divides the resolution by that amount (0.5 will divide the resolution by two for example). For lower bitrate scenarios you will use this feature to minimise blocking.
Activate Audio transcoding[edit]
Audio transcoding is a good way to save a few bytes of data to optimise your webstreaming setup. Often providers transmit in mp2 which is an inefficient format.
The best option to use here, if your player supports it, Audio Codec mp3 and bitrate of 128kbps or Audio Codec MPEG4 using a bitrate of 96kbps (mp4 is more efficient that mp3), and 2 channels to give CD-quality stereo sound. Remember this will add to the total bitrate of the stream, so remember to add this figure on to your video bitrate amount.
