ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
@end example
-@section segment
+@section segment, stream_segment, ssegment
Basic stream segmenter.
fixed duration. Output filename pattern can be set in a fashion similar to
@ref{image2}.
+@code{stream_segment} is a variant of the muxer used to write to
+streaming output formats, i.e. which do not require global headers,
+and is recommended for outputting e.g. to MPEG transport stream segments.
+@code{ssegment} is a shorter alias for @code{stream_segment}.
+
Every segment starts with a video keyframe, if a video stream is present.
+Note that if you want accurate splitting for a video file, you need to
+make the input key frames correspond to the exact splitting times
+expected by the segmenter, or the segment muxer will start the new
+segment with the key frame found next after the specified start
+time.
+
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.
+per line, by setting the option @var{segment_list}.
+
+The segment muxer supports the following options:
@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}.
+Generate also a listfile named @var{name}. If not specified no
+listfile is generated.
@item segment_list_size @var{size}
-Overwrite the listfile once it reaches @var{size} entries.
+Overwrite the listfile once it reaches @var{size} entries. If 0
+the listfile is never overwritten. Default value is 5.
+@item segment_list type @var{type}
+Specify the format for the segment list file.
+
+The following values are recognized:
+@table @option
+@item flat
+Generate a flat list for the created segments, one segment per line.
+
+@item ext
+Generate a list for the created segments, one segment per line,
+each line matching the format:
+@example
+@var{segment_filename},@var{segment_start_time},@var{segment_end_time}
+@end example
+
+@var{segment_filename} is the name of the output file generated by the
+muxer according to the provided pattern, and should not contain the
+"," character for simplifying parsing operations.
+
+@var{segment_start_time} and @var{segment_end_time} specify
+the segment start and end time expressed in seconds.
+@end table
+
+Default value is "flat".
+@item segment_time @var{time}
+Set segment duration to @var{time}. Default value is "2".
+@item segment_time_delta @var{delta}
+Specify the accuracy time when selecting the start time for a
+segment. Default value is "0".
+
+When delta is specified a key-frame will start a new segment if its
+PTS satisfies the relation:
+@example
+PTS >= start_time - time_delta
+@end example
+
+This option is useful when splitting video content, which is always
+split at GOP boundaries, in case a key frame is found just before the
+specified split time.
+
+In particular may be used in combination with the @file{ffmpeg} option
+@var{force_key_frames}. The key frame times specified by
+@var{force_key_frames} may not be set accurately because of rounding
+issues, with the consequence that a key frame time may result set just
+before the specified time. For constant frame rate videos a value of
+1/2*@var{frame_rate} should address the worst case mismatch between
+the specified time and the time set by @var{force_key_frames}.
+
+@item segment_times @var{times}
+Specify a list of split points. @var{times} contains a list of comma
+separated duration specifications, in increasing order.
@item segment_wrap @var{limit}
Wrap around segment index once it reaches @var{limit}.
@end table
+Some examples follow.
+
+@itemize
+@item
+To remux the content of file @file{in.mkv} to a list of segments
+@file{out-000.nut}, @file{out-001.nut}, etc., and write the list of
+generated segments to @file{out.list}:
+@example
+ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.list out%03d.nut
+@end example
+
+@item
+As the example above, but segment the input file according to the split
+points specified by the @var{segment_times} option:
+@example
+ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list_type ext -segment_list out.list -segment_list_size 0 -segment_times 1,2,3,5,8,13,21 out%03d.nut
+@end example
+
+@item
+As the example above, but use the @code{ffmpeg} @var{force_key_frames}
+option to force key frames in the input at the specified location, together
+with the segment option @var{segment_time_delta} to account for
+possible roundings operated when setting key frame times.
+@example
+ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -vcodec mpeg4 -acodec pcm_s16le -map 0 \
+-f segment -segment_list_type ext -segment_list out.list -segment_list_size 0 -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
+@end example
+In order to force key frames on the input file, transcoding is
+required.
+
+@item
+To convert the @file{in.mkv} to TS segments using the @code{libx264}
+and @code{libfaac} encoders:
@example
-ffmpeg -i in.mkv -c copy -map 0 -f segment -list out.list out%03d.nut
+ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a libfaac -f ssegment -segment_list out.list out%03d.ts
@end example
+@end itemize
@section mp3
projects / ffmpeg / blobdiff