ffmpeg -i INPUT -f crc -
@end example
-You can select the output format of each frame with @file{ffmpeg} by
+You can select the output format of each frame with @command{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 -
+ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
@end example
See also the @ref{framecrc} muxer.
ffmpeg -i INPUT -f framecrc -
@end example
-You can select the output format of each frame with @file{ffmpeg} by
+You can select the output format of each frame with @command{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 -
+ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
@end example
See also the @ref{crc} muxer.
+@anchor{image2}
@section image2
Image file muxer.
form @file{img%-1.jpg}, @file{img%-2.jpg}, ..., @file{img%-10.jpg},
etc.
-The following example shows how to use @file{ffmpeg} for creating a
+The following example shows how to use @command{ffmpeg} for creating a
sequence of files @file{img-001.jpeg}, @file{img-002.jpeg}, ...,
taking one image every second from the input video:
@example
-ffmpeg -i in.avi -r 1 -f image2 'img-%03d.jpeg'
+ffmpeg -i in.avi -vsync 1 -r 1 -f image2 'img-%03d.jpeg'
@end example
-Note that with @file{ffmpeg}, if the format is not specified with the
+Note that with @command{ffmpeg}, if the format is not specified with the
@code{-f} option and the output filename specifies an image file
format, the image2 muxer is automatically selected, so the previous
command can be written as:
@example
-ffmpeg -i in.avi -r 1 'img-%03d.jpeg'
+ffmpeg -i in.avi -vsync 1 -r 1 'img-%03d.jpeg'
@end example
Note also that the pattern must not necessarily contain "%d" or
"%0@var{N}d", for example to create a single image file
@file{img.jpeg} from the input video you can employ the command:
@example
-ffmpeg -i in.avi -f image2 -vframes 1 img.jpeg
+ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
@end example
The image muxer supports the .Y.U.V image file format. This format is
specify the name of the '.Y' file. The muxer will automatically open the
'.U' and '.V' files as required.
-@section mov
+@section MOV/MP4/ISMV
-MOV / MP4 muxer
+The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
+file has all the metadata about all packets stored in one location
+(written at the end of the file, it can be moved to the start for
+better playback using the @command{qt-faststart} tool). A fragmented
+file consists of a number of fragments, where packets and metadata
+about these packets are stored together. Writing a fragmented
+file has the advantage that the file is decodable even if the
+writing is interrupted (while a normal MOV/MP4 is undecodable if
+it is not properly finished), and it requires less memory when writing
+very long files (since writing normal MOV/MP4 files stores info about
+every single packet in memory until the file is closed). The downside
+is that it is less compatible with other applications.
-The muxer options are:
+Fragmentation is enabled by setting one of the AVOptions that define
+how to cut the file into fragments:
@table @option
@item -moov_size @var{bytes}
Reserves space for the moov atom at the beginning of the file instead of placing the
moov atom at the end. If the space reserved is insufficient, muxing will fail.
+@item -movflags frag_keyframe
+Start a new fragment at each video keyframe.
+@item -frag_duration @var{duration}
+Create fragments that are @var{duration} microseconds long.
+@item -frag_size @var{size}
+Create fragments that contain up to @var{size} bytes of payload data.
+@item -movflags frag_custom
+Allow the caller to manually choose when to cut fragments, by
+calling @code{av_write_frame(ctx, NULL)} to write a fragment with
+the packets written so far. (This is only useful with other
+applications integrating libavformat, not from @command{ffmpeg}.)
+@end table
+
+Additionally, the way the output file is written can be adjusted
+through a few other options:
+
+@table @option
+@item -movflags empty_moov
+Write an initial moov atom directly at the start of the file, without
+describing any samples in it. Generally, an mdat/moov pair is written
+at the start of the file, as a normal MOV/MP4 file, containing only
+a short portion of the file. With this option set, there is no initial
+mdat atom, and the moov atom only describes the tracks but has
+a zero duration.
+
+Files written with this option set do not work in QuickTime.
+This option is implicitly set when writing ismv (Smooth Streaming) files.
+@item -movflags separate_moof
+Write a separate moof (movie fragment) atom for each track. Normally,
+packets for all tracks are written in a moof atom (which is slightly
+more efficient), but with this option set, the muxer writes one moof/mdat
+pair for each track, making it easier to separate tracks.
+
+This option is implicitly set when writing ismv (Smooth Streaming) files.
@end table
+Smooth Streaming content can be pushed in real time to a publishing
+point on IIS with this muxer. Example:
+@example
+ffmpeg -re @var{<normal input/transcoding options>} -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
+@end example
+
@section mpegts
MPEG transport stream muxer.
@code{service_name} is "Service01".
@example
-ffmpeg -i file.mpg -acodec copy -vcodec copy \
+ffmpeg -i file.mpg -c copy \
-mpegts_original_network_id 0x1122 \
-mpegts_transport_stream_id 0x3344 \
-mpegts_service_id 0x5566 \
This muxer does not generate any output file, it is mainly useful for
testing or benchmarking purposes.
-For example to benchmark decoding with @file{ffmpeg} you can use the
+For example to benchmark decoding with @command{ffmpeg} you can use the
command:
@example
ffmpeg -benchmark -i INPUT -f null out.null
@end example
Note that the above command does not read or write the @file{out.null}
-file, but specifying the output file is required by the @file{ffmpeg}
+file, but specifying the output file is required by the @command{ffmpeg}
syntax.
Alternatively you can write the command as:
For example a 3D WebM clip can be created using the following command line:
@example
-ffmpeg -i sample_left_right_clip.mpg -an -vcodec libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
+ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
+@end example
+
+@section segment
+
+Basic stream segmenter.
+
+The segmenter muxer outputs streams to a number of separate files of nearly
+fixed duration. Output filename pattern can be set in a fashion similar to
+@ref{image2}.
+
+Every segment starts with a video keyframe, if a video stream is present.
+The segment muxer works best with a single constant frame rate video.
+
+Optionally it can generate a flat list of the created segments, one segment
+per line.
+
+@table @option
+@item segment_format @var{format}
+Override the inner container format, by default it is guessed by the filename
+extension.
+@item segment_time @var{t}
+Set segment duration to @var{t} seconds.
+@item segment_list @var{name}
+Generate also a listfile named @var{name}.
+@item segment_list_size @var{size}
+Overwrite the listfile once it reaches @var{size} entries.
+@end table
+
+@example
+ffmpeg -i in.mkv -c copy -map 0 -f segment -list out.list out%03d.nut
@end example
+
@c man end MUXERS
projects / ffmpeg / blobdiff