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- @chapter Demuxers
- @c man begin DEMUXERS
- Demuxers are configured elements in FFmpeg which allow to read the
- multimedia streams from a particular type of file.
- When you configure your FFmpeg build, all the supported demuxers
- are enabled by default. You can list all available ones using the
- configure option "--list-demuxers".
- You can disable all the demuxers using the configure option
- "--disable-demuxers", and selectively enable a single demuxer with
- the option "--enable-demuxer=@var{DEMUXER}", or disable it
- with the option "--disable-demuxer=@var{DEMUXER}".
- The option "-formats" of the ff* tools will display the list of
- enabled demuxers.
- The description of some of the currently available demuxers follows.
- @section image2
- Image file demuxer.
- This demuxer reads from a list of image files specified by a pattern.
- The pattern may contain the string "%d" or "%0@var{N}d", which
- specifies the position of the characters representing a sequential
- number in each filename matched by the pattern. If the form
- "%d0@var{N}d" is used, the string representing the number in each
- filename is 0-padded and @var{N} is the total number of 0-padded
- digits representing the number. The literal character '%' can be
- specified in the pattern with the string "%%".
- If the pattern contains "%d" or "%0@var{N}d", the first filename of
- the file list specified by the pattern must contain a number
- inclusively contained between 0 and 4, all the following numbers must
- be sequential. This limitation may be hopefully fixed.
- The pattern may contain a suffix which is used to automatically
- determine the format of the images contained in the files.
- For example the pattern "img-%03d.bmp" will match a sequence of
- filenames of the form @file{img-001.bmp}, @file{img-002.bmp}, ...,
- @file{img-010.bmp}, etc.; the pattern "i%%m%%g-%d.jpg" will match a
- sequence of filenames of the form @file{i%m%g-1.jpg},
- @file{i%m%g-2.jpg}, ..., @file{i%m%g-10.jpg}, etc.
- The size, the pixel format, and the format of each image must be the
- same for all the files in the sequence.
- The following example shows how to use @file{ffmpeg} for creating a
- video from the images in the file sequence @file{img-001.jpeg},
- @file{img-002.jpeg}, ..., assuming an input framerate of 10 frames per
- second:
- @example
- ffmpeg -r 10 -f image2 -i 'img-%03d.jpeg' out.avi
- @end example
- Note that the pattern must not necessarily contain "%d" or
- "%0@var{N}d", for example to convert a single image file
- @file{img.jpeg} you can employ the command:
- @example
- ffmpeg -f image2 -i img.jpeg img.png
- @end example
- @section applehttp
- Apple HTTP Live Streaming demuxer.
- This demuxer presents all AVStreams from all variant streams.
- The id field is set to the bitrate variant index number. By setting
- the discard flags on AVStreams (by pressing 'a' or 'v' in ffplay),
- the caller can decide which variant streams to actually receive.
- The total bitrate of the variant that the stream belongs to is
- available in a metadata key named "variant_bitrate".
- @c man end INPUT DEVICES
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