1 \input texinfo @c -*- texinfo -*-
3 @settitle avconv Documentation
5 @center @titlefont{avconv Documentation}
14 The generic syntax is:
18 avconv [global options] [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}...
23 @c man begin DESCRIPTION
25 avconv is a very fast video and audio converter that can also grab from
26 a live audio/video source. It can also convert between arbitrary sample
27 rates and resize video on the fly with a high quality polyphase filter.
29 As a general rule, options are applied to the next specified
30 file. Therefore, order is important, and you can have the same
31 option on the command line multiple times. Each occurrence is
32 then applied to the next input or output file.
33 Exceptions from this rule are the global options (e.g. verbosity level),
34 which should be specified first.
38 To set the video bitrate of the output file to 64kbit/s:
40 avconv -i input.avi -b 64k output.avi
44 To force the frame rate of the output file to 24 fps:
46 avconv -i input.avi -r 24 output.avi
50 To force the frame rate of the input file (valid for raw formats only)
51 to 1 fps and the frame rate of the output file to 24 fps:
53 avconv -r 1 -i input.m2v -r 24 output.avi
57 The format option may be needed for raw input files.
59 @c man end DESCRIPTION
61 @chapter Stream selection
62 @c man begin STREAM SELECTION
64 By default avconv tries to pick the "best" stream of each type present in input
65 files and add them to each output file. For video, this means the highest
66 resolution, for audio the highest channel count. For subtitle it's simply the
67 first subtitle stream.
69 You can disable some of those defaults by using @code{-vn/-an/-sn} options. For
70 full manual control, use the @code{-map} option, which disables the defaults just
73 @c man end STREAM SELECTION
78 @include avtools-common-opts.texi
84 @item -f @var{fmt} (@emph{input/output})
87 @item -i @var{filename} (@emph{input})
90 @item -y (@emph{global})
91 Overwrite output files.
93 @item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
94 @itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
95 Select an encoder (when used before an output file) or a decoder (when used
96 before an input file) for one or more streams. @var{codec} is the name of a
97 decoder/encoder or a special value @code{copy} (output only) to indicate that
98 the stream is not to be reencoded.
102 avconv -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
104 encodes all video streams with libx264 and copies all audio streams.
106 For each stream, the last matching @code{c} option is applied, so
108 avconv -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
110 will copy all the streams except the second video, which will be encoded with
111 libx264, and the 138th audio, which will be encoded with libvorbis.
113 @item -t @var{duration} (@emph{output})
114 Restrict the transcoded/captured video sequence
115 to the duration specified in seconds.
116 @code{hh:mm:ss[.xxx]} syntax is also supported.
118 @item -fs @var{limit_size} (@emph{output})
119 Set the file size limit.
121 @item -ss @var{position} (@emph{input/output})
122 When used as an input option (before @code{-i}), seeks in this input file to
123 @var{position}. When used as an output option (before an output filename),
124 decodes but discards input until the timestamps reach @var{position}. This is
125 slower, but more accurate.
127 @var{position} may be either in seconds or in @code{hh:mm:ss[.xxx]} form.
129 @item -itsoffset @var{offset} (@emph{input})
130 Set the input time offset in seconds.
131 @code{[-]hh:mm:ss[.xxx]} syntax is also supported.
132 The offset is added to the timestamps of the input files.
133 Specifying a positive offset means that the corresponding
134 streams are delayed by 'offset' seconds.
136 @item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata})
137 Set a metadata key/value pair.
139 An optional @var{metadata_specifier} may be given to set metadata
140 on streams or chapters. See @code{-map_metadata} documentation for
143 This option overrides metadata set with @code{-map_metadata}. It is
144 also possible to delete metadata by using an empty value.
146 For example, for setting the title in the output file:
148 avconv -i in.avi -metadata title="my title" out.flv
151 To set the language of the second stream:
153 avconv -i INPUT -metadata:s:1 language=eng OUTPUT
156 @item -v @var{number} (@emph{global})
157 Set the logging verbosity level.
159 @item -target @var{type} (@emph{output})
160 Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50", "pal-vcd",
161 "ntsc-svcd", ... ). All the format options (bitrate, codecs,
162 buffer sizes) are then set automatically. You can just type:
165 avconv -i myfile.avi -target vcd /tmp/vcd.mpg
168 Nevertheless you can specify additional options as long as you know
169 they do not conflict with the standard, as in:
172 avconv -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
175 @item -dframes @var{number} (@emph{output})
176 Set the number of data frames to record. This is an alias for @code{-frames:d}.
178 @item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream})
179 Stop writing to the stream after @var{framecount} frames.
181 @item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
182 @itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream})
183 Use fixed quality scale (VBR). The meaning of @var{q} is
186 @item -filter[:@var{stream_specifier}] @var{filter_graph}
187 @var{filter_graph} is a description of the filter graph to apply to
188 the stream. Use @code{-filters} to show all the available filters
189 (including also sources and sinks).
193 @section Video Options
196 @item -vframes @var{number} (@emph{output})
197 Set the number of video frames to record. This is an alias for @code{-frames:v}.
198 @item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
199 Set frame rate (Hz value, fraction or abbreviation), (default = 25).
200 @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
201 Set frame size. The format is @samp{wxh} (ffserver default = 160x128, avconv default = same as source).
202 The following abbreviations are recognized:
264 @item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream})
265 Set the video display aspect ratio specified by @var{aspect}.
267 @var{aspect} can be a floating point number string, or a string of the
268 form @var{num}:@var{den}, where @var{num} and @var{den} are the
269 numerator and denominator of the aspect ratio. For example "4:3",
270 "16:9", "1.3333", and "1.7777" are valid argument values.
272 @item -vn (@emph{output})
273 Disable video recording.
274 @item -bt @var{tolerance}
275 Set video bitrate tolerance (in bits, default 4000k).
276 Has a minimum value of: (target_bitrate/target_framerate).
277 In 1-pass mode, bitrate tolerance specifies how far ratecontrol is
278 willing to deviate from the target average bitrate value. This is
279 not related to min/max bitrate. Lowering tolerance too much has
280 an adverse effect on quality.
281 @item -maxrate @var{bitrate}
282 Set max video bitrate (in bit/s).
283 Requires -bufsize to be set.
284 @item -minrate @var{bitrate}
285 Set min video bitrate (in bit/s).
286 Most useful in setting up a CBR encode:
288 avconv -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
290 It is of little use elsewise.
291 @item -bufsize @var{size}
292 Set video buffer verifier buffer size (in bits).
293 @item -vcodec @var{codec} (@emph{output})
294 Set the video codec. This is an alias for @code{-codec:v}.
296 Use same quantizer as source (implies VBR).
298 Note that this is NOT SAME QUALITY. Do not use this option unless you know you
302 Select the pass number (1 or 2). It is used to do two-pass
303 video encoding. The statistics of the video are recorded in the first
304 pass into a log file (see also the option -passlogfile),
305 and in the second pass that log file is used to generate the video
306 at the exact requested bitrate.
307 On pass 1, you may just deactivate audio and set output to null,
308 examples for Windows and Unix:
310 avconv -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
311 avconv -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
314 @item -passlogfile @var{prefix} (@emph{global})
315 Set two-pass log file name prefix to @var{prefix}, the default file name
316 prefix is ``av2pass''. The complete file name will be
317 @file{PREFIX-N.log}, where N is a number specific to the output
320 @item -vf @var{filter_graph} (@emph{output})
321 @var{filter_graph} is a description of the filter graph to apply to
323 Use the option "-filters" to show all the available filters (including
324 also sources and sinks). This is an alias for @code{-filter:v}.
328 @section Advanced Video Options
331 @item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream})
332 Set pixel format. Use @code{-pix_fmts} to show all the supported
334 @item -sws_flags @var{flags} (@emph{input/output})
336 @item -g @var{gop_size}
337 Set the group of pictures size.
341 minimum video quantizer scale (VBR)
343 maximum video quantizer scale (VBR)
345 maximum difference between the quantizer scales (VBR)
346 @item -qblur @var{blur}
347 video quantizer scale blur (VBR) (range 0.0 - 1.0)
348 @item -qcomp @var{compression}
349 video quantizer scale compression (VBR) (default 0.5).
350 Constant of ratecontrol equation. Recommended range for default rc_eq: 0.0-1.0
352 @item -lmin @var{lambda}
353 minimum video lagrange factor (VBR)
354 @item -lmax @var{lambda}
355 max video lagrange factor (VBR)
356 @item -mblmin @var{lambda}
357 minimum macroblock quantizer scale (VBR)
358 @item -mblmax @var{lambda}
359 maximum macroblock quantizer scale (VBR)
361 These four options (lmin, lmax, mblmin, mblmax) use 'lambda' units,
362 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
364 avconv -i src.ext -lmax 21*QP2LAMBDA dst.ext
367 @item -rc_init_cplx @var{complexity}
368 initial complexity for single pass encoding
369 @item -b_qfactor @var{factor}
370 qp factor between P- and B-frames
371 @item -i_qfactor @var{factor}
372 qp factor between P- and I-frames
373 @item -b_qoffset @var{offset}
374 qp offset between P- and B-frames
375 @item -i_qoffset @var{offset}
376 qp offset between P- and I-frames
377 @item -rc_eq @var{equation}
378 Set rate control equation (see section "Expression Evaluation")
379 (default = @code{tex^qComp}).
381 When computing the rate control equation expression, besides the
382 standard functions defined in the section "Expression Evaluation", the
383 following functions are available:
389 and the following constants are available:
411 @item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
412 rate control override for specific intervals
413 @item -me_method @var{method}
414 Set motion estimation method to @var{method}.
415 Available methods are (from lowest to best quality):
418 Try just the (0, 0) vector.
427 exhaustive search (slow and marginally better than epzs)
431 Set error resilience to @var{n}.
434 FF_ER_CAREFUL (default)
440 FF_ER_VERY_AGGRESSIVE
443 @item -ec @var{bit_mask}
444 Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of
445 the following values:
448 FF_EC_GUESS_MVS (default = enabled)
450 FF_EC_DEBLOCK (default = enabled)
453 @item -bf @var{frames}
454 Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4).
455 @item -mbd @var{mode}
459 FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in avconv).
461 FF_MB_DECISION_BITS: Choose the one which needs the fewest bits.
463 FF_MB_DECISION_RD: rate distortion
466 @item -bug @var{param}
467 Work around encoder bugs that are not auto-detected.
468 @item -strict @var{strictness}
469 How strictly to follow the standards.
472 Deinterlace pictures.
474 Dump video coding statistics to @file{vstats_HHMMSS.log}.
475 @item -vstats_file @var{file}
476 Dump video coding statistics to @var{file}.
477 @item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream})
478 top=1/bottom=0/auto=-1 field first
479 @item -dc @var{precision}
481 @item -vtag @var{fourcc/tag} (@emph{output})
482 Force video tag/fourcc. This is an alias for @code{-tag:v}.
483 @item -qphist (@emph{global})
485 @item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream})
486 Force key frames at the specified timestamps, more precisely at the first
487 frames after each specified time.
488 This option can be useful to ensure that a seek point is present at a
489 chapter mark or any other designated place in the output file.
490 The timestamps must be specified in ascending order.
493 @section Audio Options
496 @item -aframes @var{number} (@emph{output})
497 Set the number of audio frames to record. This is an alias for @code{-frames:a}.
498 @item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream})
499 Set the audio sampling frequency. For output streams it is set by
500 default to the frequency of the corresponding input stream. For input
501 streams this option only makes sense for audio grabbing devices and raw
502 demuxers and is mapped to the corresponding demuxer options.
503 @item -aq @var{q} (@emph{output})
504 Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
505 @item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream})
506 Set the number of audio channels. For output streams it is set by
507 default to the number of input audio channels. For input streams
508 this option only makes sense for audio grabbing devices and raw demuxers
509 and is mapped to the corresponding demuxer options.
510 @item -an (@emph{output})
511 Disable audio recording.
512 @item -acodec @var{codec} (@emph{input/output})
513 Set the audio codec. This is an alias for @code{-codec:a}.
514 @item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
515 Set the audio sample format. Use @code{-help sample_fmts} to get a list
516 of supported sample formats.
519 @section Advanced Audio options:
522 @item -atag @var{fourcc/tag} (@emph{output})
523 Force audio tag/fourcc. This is an alias for @code{-tag:a}.
524 @item -audio_service_type @var{type}
525 Set the type of service that the audio stream contains.
528 Main Audio Service (default)
548 @section Subtitle options:
551 @item -scodec @var{codec} (@emph{input/output})
552 Set the subtitle codec. This is an alias for @code{-codec:s}.
553 @item -sn (@emph{output})
554 Disable subtitle recording.
557 @section Audio/Video grab options
560 @item -isync (@emph{global})
561 Synchronize read on input.
564 @section Advanced options
567 @item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] (@emph{output})
569 Designate one or more input streams as a source for the output file. Each input
570 stream is identified by the input file index @var{input_file_id} and
571 the input stream index @var{input_stream_id} within the input
572 file. Both indices start at 0. If specified,
573 @var{sync_file_id}:@var{stream_specifier} sets which input stream
574 is used as a presentation sync reference.
576 The first @code{-map} option on the command line specifies the
577 source for output stream 0, the second @code{-map} option specifies
578 the source for output stream 1, etc.
580 A @code{-} character before the stream identifier creates a "negative" mapping.
581 It disables matching streams from already created mappings.
583 For example, to map ALL streams from the first input file to output
585 avconv -i INPUT -map 0 output
588 For example, if you have two audio streams in the first input file,
589 these streams are identified by "0:0" and "0:1". You can use
590 @code{-map} to select which streams to place in an output file. For
593 avconv -i INPUT -map 0:1 out.wav
595 will map the input stream in @file{INPUT} identified by "0:1" to
596 the (single) output stream in @file{out.wav}.
598 For example, to select the stream with index 2 from input file
599 @file{a.mov} (specified by the identifier "0:2"), and stream with
600 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
601 and copy them to the output file @file{out.mov}:
603 avconv -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
606 To select all video and the third audio stream from an input file:
608 avconv -i INPUT -map 0:v -map 0:a:2 OUTPUT
611 To map all the streams except the second audio, use negative mappings
613 avconv -i INPUT -map 0 -map -0:a:1 OUTPUT
616 Note that using this option disables the default mappings for this output file.
618 @item -map_metadata[:@var{metadata_type}][:@var{index}] @var{infile}[:@var{metadata_type}][:@var{index}] (@emph{output,per-metadata})
619 Set metadata information of the next output file from @var{infile}. Note that
620 those are file indices (zero-based), not filenames.
621 Optional @var{metadata_type} parameters specify, which metadata to copy - (g)lobal
622 (i.e. metadata that applies to the whole file), per-(s)tream, per-(c)hapter or
623 per-(p)rogram. All metadata specifiers other than global must be followed by the
624 stream/chapter/program index. If metadata specifier is omitted, it defaults to
627 By default, global metadata is copied from the first input file,
628 per-stream and per-chapter metadata is copied along with streams/chapters. These
629 default mappings are disabled by creating any mapping of the relevant type. A negative
630 file index can be used to create a dummy mapping that just disables automatic copying.
632 For example to copy metadata from the first stream of the input file to global metadata
635 avconv -i in.ogg -map_metadata 0:s:0 out.mp3
637 @item -map_chapters @var{input_file_index} (@emph{output})
638 Copy chapters from input file with index @var{input_file_index} to the next
639 output file. If no chapter mapping is specified, then chapters are copied from
640 the first input file with at least one chapter. Use a negative file index to
641 disable any chapter copying.
643 Print specific debug info.
644 @item -benchmark (@emph{global})
645 Show benchmarking information at the end of an encode.
646 Shows CPU time used and maximum memory consumption.
647 Maximum memory consumption is not supported on all systems,
648 it will usually display as 0 if not supported.
649 @item -dump (@emph{global})
650 Dump each input packet.
651 @item -hex (@emph{global})
652 When dumping packets, also dump the payload.
654 Set RTP payload size in bytes.
655 @item -re (@emph{input})
656 Read input at native frame rate. Mainly used to simulate a grab device.
657 @item -threads @var{count}
659 @item -vsync @var{parameter}
664 Each frame is passed with its timestamp from the demuxer to the muxer.
666 Frames will be duplicated and dropped to achieve exactly the requested
669 Frames are passed through with their timestamp or dropped so as to
670 prevent 2 frames from having the same timestamp.
672 Chooses between 1 and 2 depending on muxer capabilities. This is the
676 With -map you can select from which stream the timestamps should be
677 taken. You can leave either video or audio unchanged and sync the
678 remaining stream(s) to the unchanged one.
680 @item -async @var{samples_per_second}
681 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
682 the parameter is the maximum samples per second by which the audio is changed.
683 -async 1 is a special case where only the start of the audio stream is corrected
684 without any later correction.
686 Copy timestamps from input to output.
688 Copy input stream time base from input to output when stream copying.
690 Finish encoding when the shortest input stream ends.
691 @item -dts_delta_threshold
692 Timestamp discontinuity delta threshold.
693 @item -muxdelay @var{seconds} (@emph{input})
694 Set the maximum demux-decode delay.
695 @item -muxpreload @var{seconds} (@emph{input})
696 Set the initial demux-decode delay.
697 @item -streamid @var{output-stream-index}:@var{new-value} (@emph{output})
698 Assign a new stream-id value to an output stream. This option should be
699 specified prior to the output filename to which it applies.
700 For the situation where multiple output files exist, a streamid
701 may be reassigned to a different value.
703 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
704 an output mpegts file:
706 avconv -i infile -streamid 0:33 -streamid 1:36 out.ts
709 @item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream})
710 Set bitstream filters for matching streams. @var{bistream_filters} is
711 a comma-separated list of bitstream filters. Use the @code{-bsfs} option
712 to get the list of bitstream filters.
714 avconv -i h264.mp4 -c:v copy -vbsf h264_mp4toannexb -an out.h264
717 avconv -i file.mov -an -vn -sbsf mov2textsub -c:s copy -f rawvideo sub.txt
720 @item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{output,per-stream})
721 Force a tag/fourcc for matching streams.
730 For streaming at very low bitrate application, use a low frame rate
731 and a small GOP size. This is especially true for RealVideo where
732 the Linux player does not seem to be very fast, so it can miss
733 frames. An example is:
736 avconv -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
740 The parameter 'q' which is displayed while encoding is the current
741 quantizer. The value 1 indicates that a very good quality could
742 be achieved. The value 31 indicates the worst quality. If q=31 appears
743 too often, it means that the encoder cannot compress enough to meet
744 your bitrate. You must either increase the bitrate, decrease the
745 frame rate or decrease the frame size.
748 If your computer is not fast enough, you can speed up the
749 compression at the expense of the compression ratio. You can use
750 '-me zero' to speed up motion estimation, and '-intra' to disable
751 motion estimation completely (you have only I-frames, which means it
752 is about as good as JPEG compression).
755 To have very low audio bitrates, reduce the sampling frequency
756 (down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
759 To have a constant quality (but a variable bitrate), use the option
760 '-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
767 @c man begin EXAMPLES
769 @section Video and Audio grabbing
771 If you specify the input format and device then avconv can grab video
775 avconv -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
778 Note that you must activate the right video source and channel before
779 launching avconv with any TV viewer such as
780 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
781 have to set the audio recording levels correctly with a
784 @section X11 grabbing
786 Grab the X11 display with avconv via
789 avconv -f x11grab -s cif -r 25 -i :0.0 /tmp/out.mpg
792 0.0 is display.screen number of your X11 server, same as
793 the DISPLAY environment variable.
796 avconv -f x11grab -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg
799 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
800 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
802 @section Video and Audio file format conversion
804 Any supported file format and protocol can serve as input to avconv:
809 You can use YUV files as input:
812 avconv -i /tmp/test%d.Y /tmp/out.mpg
815 It will use the files:
817 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
818 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
821 The Y files use twice the resolution of the U and V files. They are
822 raw files, without header. They can be generated by all decent video
823 decoders. You must specify the size of the image with the @option{-s} option
824 if avconv cannot guess it.
827 You can input from a raw YUV420P file:
830 avconv -i /tmp/test.yuv /tmp/out.avi
833 test.yuv is a file containing raw YUV planar data. Each frame is composed
834 of the Y plane followed by the U and V planes at half vertical and
835 horizontal resolution.
838 You can output to a raw YUV420P file:
841 avconv -i mydivx.avi hugefile.yuv
845 You can set several input files and output files:
848 avconv -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
851 Converts the audio file a.wav and the raw YUV video file a.yuv
855 You can also do audio and video conversions at the same time:
858 avconv -i /tmp/a.wav -ar 22050 /tmp/a.mp2
861 Converts a.wav to MPEG audio at 22050 Hz sample rate.
864 You can encode to several formats at the same time and define a
865 mapping from input stream to output streams:
868 avconv -i /tmp/a.wav -map 0:a -b 64k /tmp/a.mp2 -map 0:a -b 128k /tmp/b.mp2
871 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
872 file:index' specifies which input stream is used for each output
873 stream, in the order of the definition of output streams.
876 You can transcode decrypted VOBs:
879 avconv -i snatch_1.vob -f avi -c:v mpeg4 -b:v 800k -g 300 -bf 2 -c:a libmp3lame -b:a 128k snatch.avi
882 This is a typical DVD ripping example; the input is a VOB file, the
883 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
884 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
885 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
886 input video. Furthermore, the audio stream is MP3-encoded so you need
887 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
888 The mapping is particularly useful for DVD transcoding
889 to get the desired audio language.
891 NOTE: To see the supported input formats, use @code{avconv -formats}.
894 You can extract images from a video, or create a video from many images:
896 For extracting images from a video:
898 avconv -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
901 This will extract one video frame per second from the video and will
902 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
903 etc. Images will be rescaled to fit the new WxH values.
905 If you want to extract just a limited number of frames, you can use the
906 above command in combination with the -vframes or -t option, or in
907 combination with -ss to start extracting from a certain point in time.
909 For creating a video from many images:
911 avconv -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
914 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
915 composed of three digits padded with zeroes to express the sequence
916 number. It is the same syntax supported by the C printf function, but
917 only formats accepting a normal integer are suitable.
920 You can put many streams of the same type in the output:
923 avconv -i test1.avi -i test2.avi -map 0.3 -map 0.2 -map 0.1 -map 0.0 -c copy test12.nut
926 The resulting output file @file{test12.avi} will contain first four streams from
927 the input file in reverse order.
933 @include encoders.texi
934 @include demuxers.texi
937 @include outdevs.texi
938 @include protocols.texi
939 @include bitstream_filters.texi
940 @include filters.texi
941 @include metadata.texi
946 @settitle avconv video converter
949 ffplay(1), ffprobe(1), ffserver(1) and the FFmpeg HTML documentation