From 77d4ed7a127b88f9b8ddd741c65e678198feb285 Mon Sep 17 00:00:00 2001 From: Stefano Sabatini <stefano.sabatini-lala@poste.it> Date: Tue, 1 Feb 2011 01:03:48 +0100 Subject: Add documentation for the framecrc muxer. Signed-off-by: Janne Grunau <janne-ffmpeg@jannau.net> --- doc/muxers.texi | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) (limited to 'doc/muxers.texi') diff --git a/doc/muxers.texi b/doc/muxers.texi index 63aa95c317..9e824bf289 100644 --- a/doc/muxers.texi +++ b/doc/muxers.texi @@ -18,6 +18,7 @@ enabled muxers. A description of some of the currently available muxers follows. +@anchor{crc} @section crc CRC (Cyclic Redundancy Check) testing format. @@ -50,6 +51,45 @@ and the input video converted to MPEG-2 video, use the command: ffmpeg -i INPUT -acodec pcm_u8 -vcodec mpeg2video -f crc - @end example +See also the @code{framecrc} muxer (@pxref{framecrc}). + +@anchor{framecrc} +@section framecrc + +Per-frame CRC (Cyclic Redundancy Check) testing format. + +This muxer computes and prints the Adler-32 CRC for each decoded audio +and video frame. 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 line for each audio and video +frame of the form: @var{stream_index}, @var{frame_dts}, +@var{frame_size}, 0x@var{CRC}, where @var{CRC} is a hexadecimal +number 0-padded to 8 digits containing the CRC of the decoded frame. + +For example to compute the CRC of each decoded frame in the input, and +store it in the file @file{out.crc}: +@example +ffmpeg -i INPUT -f framecrc out.crc +@end example + +You can print the CRC of each decoded frame to stdout with the command: +@example +ffmpeg -i INPUT -f framecrc - +@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 each decoded input audio frame converted to PCM +unsigned 8-bit and of each decoded input video frame converted to +MPEG-2 video, use the command: +@example +ffmpeg -i INPUT -acodec pcm_u8 -vcodec mpeg2video -f framecrc - +@end example + +See also the @code{crc} muxer (@pxref{crc}). + @section image2 Image file muxer. -- cgit v1.2.3