From: Stefano Sabatini Date: Mon, 31 Jan 2011 14:20:09 +0000 (+0100) Subject: Add documentation for the crc muxer. X-Git-Tag: v0.7b1~653 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a4effe432f4aa59d52465b88589f92addf3afd3e;p=platform%2Fupstream%2Flibav.git Add documentation for the crc muxer. Signed-off-by: Janne Grunau --- diff --git a/doc/muxers.texi b/doc/muxers.texi index d661c96..63aa95c 100644 --- a/doc/muxers.texi +++ b/doc/muxers.texi @@ -18,6 +18,38 @@ enabled muxers. A description of some of the currently available muxers follows. +@section crc + +CRC (Cyclic Redundancy Check) testing format. + +This muxer computes and prints the Adler-32 CRC of all the input audio +and video frames. By default audio frames are converted to signed +16-bit raw audio and video frames to raw video before computing the +CRC. + +The output of the muxer consists of a single line of the form: +CRC=0x@var{CRC}, where @var{CRC} is a hexadecimal number 0-padded to +8 digits containing the CRC for all the decoded input frames. + +For example to compute the CRC of the input, and store it in the file +@file{out.crc}: +@example +ffmpeg -i INPUT -f crc out.crc +@end example + +You can print the CRC to stdout with the command: +@example +ffmpeg -i INPUT -f crc - +@end example + +You can select the output format of each frame with @file{ffmpeg} by +specifying the audio and video codec and format. For example to +compute the CRC of the input audio converted to PCM unsigned 8-bit +and the input video converted to MPEG-2 video, use the command: +@example +ffmpeg -i INPUT -acodec pcm_u8 -vcodec mpeg2video -f crc - +@end example + @section image2 Image file muxer.