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mod_fsv implements functions to record and play back RTP video frames in FreeSWITCH.


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Format Interface

You could use the file interface for audio only record/playback

Dialplan app:


uuid_record also can record video, but at this time it only records one leg of audio and video.

Recording in conference is also possible with:

File Format

FSV probably means "FreeSWITCH Video". An FSV file is a native format to store audio (L16) and video (codec native) frames as seen inside RTP packets. The format is machine-dependent; especially there seems to be no allowance in the code for endian-ness (so files recorded on a big-endian machine for example would not work on a little-endian machine, etc).

The file header consists of a 4 byte version ID, 32 byte IANA video codec name (presumably RFC4855 and similarly-registered names), 128 byte video format descriptor (the content of the SDP format-specific parameters "fmtp" attribute field), 4 byte audio rate, 4 byte audio packetization time, and a creation time tag.

The frames are stored in the order received. A frame header, presumably 4 bytes in length (but stored as an "int", in native endian), is used; the top bit is one if frame is video, zero if audio; the 31 lower bits are used to store the frame length.

Conversation About Packetization and File Formatting

I'm going to come back and clean this up when i have a little more time to think about how to word it as documentation. – Chris Tunbridge Destreyf

Related Conversation:

irc #freeswitch


Try calling 9193 and 9194 in the 'vanilla' dialplan with a video phone.