Revision 20a4b9e9 doc/muxers.texi

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doc/muxers.texi
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A description of some of the currently available muxers follows.
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@anchor{crc}
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@section crc
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CRC (Cyclic Redundancy Check) testing format.
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ffmpeg -i INPUT -acodec pcm_u8 -vcodec mpeg2video -f crc -
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@end example
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See also the @code{framecrc} muxer (@pxref{framecrc}).
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@anchor{framecrc}
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@section framecrc
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Per-frame CRC (Cyclic Redundancy Check) testing format.
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This muxer computes and prints the Adler-32 CRC for each decoded audio
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and video frame. By default audio frames are converted to signed
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16-bit raw audio and video frames to raw video before computing the
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CRC.
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The output of the muxer consists of a line for each audio and video
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frame of the form: @var{stream_index}, @var{frame_dts},
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@var{frame_size}, 0x@var{CRC}, where @var{CRC} is a hexadecimal
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number 0-padded to 8 digits containing the CRC of the decoded frame.
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For example to compute the CRC of each decoded frame in the input, and
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store it in the file @file{out.crc}:
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@example
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ffmpeg -i INPUT -f framecrc out.crc
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@end example
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You can print the CRC of each decoded frame to stdout with the command:
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@example
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ffmpeg -i INPUT -f framecrc -
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@end example
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You can select the output format of each frame with @file{ffmpeg} by
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specifying the audio and video codec and format. For example, to
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compute the CRC of each decoded input audio frame converted to PCM
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unsigned 8-bit and of each decoded input video frame converted to
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MPEG-2 video, use the command:
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@example
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ffmpeg -i INPUT -acodec pcm_u8 -vcodec mpeg2video -f framecrc -
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@end example
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See also the @code{crc} muxer (@pxref{crc}).
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@section image2
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Image file muxer.

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