Axis Communications 210A - Manual (Page 16)

16 AXIS 210/210A/211/211A - Video Streams
Other MPEG-4 clients
Although it may be possible to use other clients to view the MPEG-4 stream, this is not
guaranteed by Axis.
For some other clients, e.g. QuickTime™ the Video Object Type must be set to Simple. It
may also be necessary to adjust the advanced MPEG-4 settings.
To assess the video stream from e.g. QuickTime™ the following path can be used:
rtsp:///mpeg4/media.amp
This path is for all supported methods, and the client will negotiate with the AXIS
210/210A/211/211A to determine exactly which transport protocol to use.
Audio Stream Types (AXIS 210A/211A only)
The stream types for audio are:
• G.711 - International standard for encoding wired-telephone audio. Uses PCM samples
to compress audio where higher signal values are compressed more than lower values.
In Axis products, this sets the coding type to µ-law 64 kbit/s.
• G.726 - Uses PCM samples to code the difference between samples (ADPCM). Reduces
bandwidth without losing too much useful audio. In Axis products, this sets the coded
bit rate to 24 or 32 kbit/s.
All stream types are ITU-T standards and operate on frequencies up to 4 kHz.
Audio transmission methods (AXIS 210A/211A only)
The audio stream can be accessed in the Live View page via Motion JPEG or MPEG-4.
Using Motion JPEG
The basic audio transmission method used in conjunction with Motion JPEG video
streaming is transmission over HTTP. The video and audio streams are not synchronized
when using Motion JPEG, so the streams may be slightly out of sync. The latency in any
stream should be low, but this will depend on the network infrastructure.
Using MPEG-4
When using MPEG-4, audio is streamed using the same protocol as the video stream.
When audio is transmitted using MPEG-4, the AXIS 210A/211A sends synchronization
information along with the streams to the client performing the synchronization.
Note:
Audio is streamed from the client to the server over HTTP when using Motion JPEG and MPEG-4.