1 \input texinfo @c -*- texinfo -*-
3 @settitle FFmpeg Formats Documentation
5 @center @titlefont{FFmpeg Formats Documentation}
13 @c man begin DESCRIPTION
15 This document describes the supported formats (muxers and demuxers)
16 provided by the libavformat library.
18 @c man end DESCRIPTION
20 @chapter Format Options
21 @c man begin FORMAT OPTIONS
23 The libavformat library provides some generic global options, which
24 can be set on all the muxers and demuxers. In addition each muxer or
25 demuxer may support so-called private options, which are specific for
28 Options may be set by specifying -@var{option} @var{value} in the
29 FFmpeg tools, or by setting the value explicitly in the
30 @code{AVFormatContext} options or using the @file{libavutil/opt.h} API
33 The list of supported options follows:
36 @item avioflags @var{flags} (@emph{input/output})
43 @item probesize @var{integer} (@emph{input})
44 Set probing size in bytes, i.e. the size of the data to analyze to get
45 stream information. A higher value will allow to detect more
46 information in case it is dispersed into the stream, but will increase
47 latency. Must be an integer not lesser than 32. It is 5000000 by default.
49 @item packetsize @var{integer} (@emph{output})
52 @item fflags @var{flags} (@emph{input/output})
62 Do not fill in missing values that can be exactly calculated.
64 Disable AVParsers, this needs @code{+nofillin} too.
68 Discard corrupted frames.
70 Try to interleave output packets by DTS.
72 Do not merge side data.
74 Enable RTP MP4A-LATM payload.
76 Reduce the latency introduced by optional buffering
79 @item analyzeduration @var{integer} (@emph{input})
80 Specify how many microseconds are analyzed to probe the input. A
81 higher value will allow to detect more accurate information, but will
82 increase latency. It defaults to 5,000,000 microseconds = 5 seconds.
84 @item cryptokey @var{hexadecimal string} (@emph{input})
87 @item indexmem @var{integer} (@emph{input})
88 Set max memory used for timestamp index (per stream).
90 @item rtbufsize @var{integer} (@emph{input})
91 Set max memory used for buffering real-time frames.
93 @item fdebug @var{flags} (@emph{input/output})
94 Print specific debug info.
101 @item max_delay @var{integer} (@emph{input/output})
102 Set maximum muxing or demuxing delay in microseconds.
104 @item fpsprobesize @var{integer} (@emph{input})
105 Set number of frames used to probe fps.
107 @item audio_preload @var{integer} (@emph{output})
108 Set microseconds by which audio packets should be interleaved earlier.
110 @item chunk_duration @var{integer} (@emph{output})
111 Set microseconds for each chunk.
113 @item chunk_size @var{integer} (@emph{output})
114 Set size in bytes for each chunk.
116 @item err_detect, f_err_detect @var{flags} (@emph{input})
117 Set error detection flags. @code{f_err_detect} is deprecated and
118 should be used only via the @command{ffmpeg} tool.
123 Verify embedded CRCs.
125 Detect bitstream specification deviations.
127 Detect improper bitstream length.
129 Abort decoding on minor error detection.
131 Consider things that violate the spec and have not been seen in the
134 Consider all spec non compliancies as errors.
136 Consider things that a sane encoder should not do as an error.
139 @item use_wallclock_as_timestamps @var{integer} (@emph{input})
140 Use wallclock as timestamps.
142 @item avoid_negative_ts @var{integer} (@emph{output})
143 Shift timestamps to make them positive. A value of 1 enables shifting,
144 a value of 0 disables it, the default value of -1 enables shifting
145 when required by the target format.
147 When shifting is enabled, all output timestamps are shifted by the
148 same amount. Audio, video, and subtitles desynching and relative
149 timestamp differences are preserved compared to how they would have
150 been without shifting.
152 Also note that this affects only leading negative timestamps, and not
153 non-monotonic negative timestamps.
155 @item flush_packets @var{integer} (@emph{output})
156 Flush the underlying I/O stream after each packet. Default 1 enables it, and
157 has the effect of reducing the latency; 0 disables it and may slightly
158 increase performance in some cases.
161 @c man end FORMAT OPTIONS
163 @include demuxers.texi
165 @include metadata.texi
170 @url{ffmpeg.html,ffmpeg}, @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffserver.html,ffserver},
171 @url{libavformat.html,libavformat}
175 ffmpeg(1), ffplay(1), ffprobe(1), ffserver(1), libavformat(3)
178 @include authors.texi
182 @setfilename ffmpeg-formats
183 @settitle FFmpeg formats