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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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@section image2
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Image file muxer.
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This muxer writes video frames to multiple image files specified by a
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pattern.
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The pattern may contain the string "%d" or "%0@var{N}d", which
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specifies the position of the characters representing a numbering in
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the filenames. If the form "%d0@var{N}d" is used, the string
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representing the number in each filename is 0-padded to @var{N}
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digits. The literal character '%' can be specified in the pattern with
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the string "%%".
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If the pattern contains "%d" or "%0@var{N}d", the first filename of
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the file list specified will contain the number 1, all the following
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numbers will be sequential.
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The pattern may contain a suffix which is used to automatically
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determine the format of the image files to write.
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For example the pattern "img-%03d.bmp" will specify a sequence of
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filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
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@file{img-010.bmp}, etc.
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The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
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form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
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etc.
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The following example shows how to use @file{ffmpeg} for creating a
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sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
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taking one image every second from the input video:
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@example
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ffmpeg -i in.avi -r 1 -f image2 'img-%03d.jpeg'
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@end example
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Note that with @file{ffmpeg}, if the format is not specified with the
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@code{-f} option and the output filename specifies an image file
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format, the image2 muxer is automatically selected, so the previous
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command can be written as:
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@example
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ffmpeg -i in.avi -r 1 'img-%03d.jpeg'
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@end example
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Note also that the pattern must not necessarily contain "%d" or
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"%0@var{N}d", for example to create a single image file
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@file{img.jpeg} from the input video you can employ the command:
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@example
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ffmpeg -i in.avi -f image2 -vframes 1 img.jpeg
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@end example
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@c man end MUXERS

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