@item -stats (@emph{global})
Print encoding progress/statistics. On by default.
+@item -progress @var{url} (@emph{global})
+Send program-friendly progress information to @var{url}.
+
+Progress information is written approximately every second and at the end of
+the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key}
+consists of only alphanumeric characters. The last key of a sequence of
+progress information is always "progress".
+
+@item -stdin
+Enable interaction on standard input. On by default unless standard input is
+used as an input. To explicitly disable interaction you need to specify
+@code{-nostdin}.
+
+Disabling interaction on standard input is useful, for example, if
+ffmpeg is in the background process group. Roughly the same result can
+be achieved with @code{ffmpeg ... < /dev/null} but it requires a
+shell.
+
@item -debug_ts (@emph{global})
Print timestamp information. It is off by default. This option is
mostly useful for testing and debugging purposes, and the output
Deprecated, see -bsf
@end table
-@section Audio/Video grab options
+@section Advanced Subtitle options:
@table @option
-@item -isync (@emph{global})
-Synchronize read on input.
+
+@item -fix_sub_duration
+Fix subtitles durations. For each subtitle, wait for the next packet in the
+same stream and adjust the duration of the first to avoid overlap. This is
+necessary with some subtitles codecs, especially DVB subtitles, because the
+duration in the original packet is only a rough estimate and the end is
+actually marked by an empty subtitle frame. Failing to use this option when
+necessary can result in exaggerated durations or muxing failures due to
+non-monotonic timestamps.
+
+Note that this option will delay the output of all data until the next
+subtitle packet is decoded: it may increase memory consumption and latency a
+lot.
+
@end table
@section Advanced options
mono audio streams into one single stereo channel audio stream (and keep the
video stream), you can use the following command:
@example
-ffmpeg -i input.mkv -f lavfi -i "
-amovie=input.mkv:si=1 [a1];
-amovie=input.mkv:si=2 [a2];
-[a1][a2] amerge" -c:a pcm_s16le -c:v copy output.mkv
+ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
@end example
@item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata})
When dumping packets, also dump the payload.
@item -re (@emph{input})
Read input at native frame rate. Mainly used to simulate a grab device.
+By default @command{ffmpeg} attempts to read the input(s) as fast as possible.
+This option will slow down the reading of the input(s) to the native frame rate
+of the input(s). It is useful for real-time output (e.g. live streaming). If
+your input(s) is coming from some other live streaming source (through HTTP or
+UDP for example) the server might already be in real-time, thus the option will
+likely not be required. On the other hand, this is meaningful if your input(s)
+is a file you are trying to push in real-time.
@item -loop_input
Loop over the input stream. Currently it works only for image
streams. This option is used for automatic FFserver testing.
Default value is -1.
-@item -shortest
+@item -shortest (@emph{output})
Finish encoding when the shortest input stream ends.
@item -dts_delta_threshold
Timestamp discontinuity delta threshold.
Output link labels are referred to with @option{-map}. Unlabeled outputs are
added to the first output file.
+Note that with this option it is possible to use only lavfi sources without
+normal input files.
+
For example, to overlay an image over video
@example
ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
@example
ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
@end example
+
+To generate 5 seconds of pure red video using lavfi @code{color} source:
+@example
+ffmpeg -filter_complex 'color=red' -t 5 out.mkv
+@end example
@end table
+As a special exception, you can use a bitmap subtitle stream as input: it
+will be converted into a video with the same size as the largest video in
+the file, or 720×576 if no video is present. Note that this is an
+experimental and temporary solution. It will be removed once libavfilter has
+proper support for subtitles.
+
+For example, to hardcode subtitles on top of a DVB-T recording stored in
+MPEG-TS format, delaying the subtitles by 1 second:
+@example
+ffmpeg -i input.ts -filter_complex \
+ '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
+ -sn -map '#0x2dc' output.mkv
+@end example
+(0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
+audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)
+
@section Preset files
A preset file contains a sequence of @var{option}=@var{value} pairs,
one for each line, specifying a sequence of options which would be
directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
or in a @file{ffpresets} folder along the executable on win32,
-in that order. For example, if the argument is @code{libx264-max}, it will
-search for the file @file{libx264-max.ffpreset}.
+in that order. For example, if the argument is @code{libvpx-1080p}, it will
+search for the file @file{libvpx-1080p.ffpreset}.
If no such file is found, then ffmpeg will search for a file named
@var{codec_name}-@var{arg}.ffpreset in the above-mentioned
directories, where @var{codec_name} is the name of the codec to which
the preset file options will be applied. For example, if you select
-the video codec with @code{-vcodec libx264} and use @code{-vpre max},
-then it will search for the file @file{libx264-max.ffpreset}.
+the video codec with @code{-vcodec libvpx} and use @code{-vpre 1080p},
+then it will search for the file @file{libvpx-1080p.ffpreset}.
@c man end OPTIONS
@chapter Tips
number. It is the same syntax supported by the C printf function, but
only formats accepting a normal integer are suitable.
-When importing an image sequence, -i also supports expanding shell-like
-wildcard patterns (globbing) internally. To lower the chance of interfering
-with your actual file names and the shell's glob expansion, you are required
-to activate glob meta characters by prefixing them with a single @code{%}
-character, like in @code{foo-%*.jpeg}, @code{foo-%?%?%?.jpeg} or
-@code{foo-00%[234%]%*.jpeg}.
-If your filename actually contains a character sequence of a @code{%} character
-followed by a glob character, you must double the @code{%} character to escape
-it. Imagine your files begin with @code{%?-foo-}, then you could use a glob
-pattern like @code{%%?-foo-%*.jpeg}. For input patterns that could be both a
-printf or a glob pattern, ffmpeg will assume it is a glob pattern.
+When importing an image sequence, -i also supports expanding
+shell-like wildcard patterns (globbing) internally, by selecting the
+image2-specific @code{-pattern_type glob} option.
+
+For example, for creating a video from filenames matching the glob pattern
+@code{foo-*.jpeg}:
+@example
+ffmpeg -f image2 -pattern_type glob -i 'foo-*.jpeg' -r 12 -s WxH foo.avi
+@end example
@item
You can put many streams of the same type in the output:
projects / ffmpeg / blobdiff