1 \input texinfo @c -*- texinfo -*-
3 @settitle avconv Documentation
5 @center @titlefont{avconv Documentation}
14 The generic syntax is:
18 avconv [[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 The command line interface is designed to be intuitive, in the sense
30 that avconv tries to figure out all parameters that can possibly be
31 derived automatically. You usually only have to specify the target
34 As a general rule, options are applied to the next specified
35 file. Therefore, order is important, and you can have the same
36 option on the command line multiple times. Each occurrence is
37 then applied to the next input or output file.
41 To set the video bitrate of the output file to 64kbit/s:
43 avconv -i input.avi -b 64k output.avi
47 To force the frame rate of the output file to 24 fps:
49 avconv -i input.avi -r 24 output.avi
53 To force the frame rate of the input file (valid for raw formats only)
54 to 1 fps and the frame rate of the output file to 24 fps:
56 avconv -r 1 -i input.m2v -r 24 output.avi
60 The format option may be needed for raw input files.
62 By default avconv tries to convert as losslessly as possible: It
63 uses the same audio and video parameters for the outputs as the one
64 specified for the inputs.
66 @c man end DESCRIPTION
68 @chapter Stream selection
69 @c man begin STREAM SELECTION
71 By default avconv tries to pick the "best" stream of each type present in input
72 files and add them to each output file. For video, this means the highest
73 resolution, for audio the highest channel count. For subtitle it's simply the
74 first subtitle stream.
76 You can disable some of those defaults by using @code{-vn/-an/-sn} options. For
77 full manual control, use the @code{-map} option, which disables the defaults just
80 @c man end STREAM SELECTION
85 @include fftools-common-opts.texi
94 @item -i @var{filename}
98 Overwrite output files.
100 @item -c[:@var{stream_type}][:@var{stream_index}] @var{codec}
101 @item -codec[:@var{stream_type}][:@var{stream_index}] @var{codec}
102 Select an encoder (when used before an output file) or a decoder (when used
103 before an input file) for one or more streams. @var{codec} is the name of a
104 decoder/encoder or a special value @code{copy} (output only) to indicate that
105 the stream is not to be reencoded.
107 @var{stream_type} may be 'v' for video, 'a' for audio, 's' for subtitle and 'd'
108 for data streams. @var{stream_index} is a global zero-based stream index if
109 @var{stream_type} isn't given, otherwise it counts only streams of the given
110 type. If @var{stream_index} is omitted, this option applies to all streams of
111 the given type or all streams of any type if @var{stream_type} is missing as
112 well (note that this only makes sense when all streams are of the same type or
113 @var{codec} is @code{copy}).
117 avconv -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
119 encodes all video streams with libx264 and copies all audio streams.
121 For each stream, the last matching @code{c} option is applied, so
123 avconv -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
125 will copy all the streams except the second video, which will be encoded with
126 libx264, and the 138th audio, which will be encoded with libvorbis.
128 @item -t @var{duration}
129 Restrict the transcoded/captured video sequence
130 to the duration specified in seconds.
131 @code{hh:mm:ss[.xxx]} syntax is also supported.
133 @item -fs @var{limit_size}
134 Set the file size limit.
136 @item -ss @var{position}
137 When used as an input option (before @code{-i}), seeks in this input file to
138 @var{position}. When used as an output option (before an output filename),
139 decodes but discards input until the timestamps reach @var{position}. This is
140 slower, but more accurate.
142 @var{position} may be either in seconds or in @code{hh:mm:ss[.xxx]} form.
144 @item -itsoffset @var{offset}
145 Set the input time offset in seconds.
146 @code{[-]hh:mm:ss[.xxx]} syntax is also supported.
147 The offset is added to the timestamps of the input files.
148 Specifying a positive offset means that the corresponding
149 streams are delayed by 'offset' seconds.
151 @item -timestamp @var{time}
152 Set the recording timestamp in the container.
153 The syntax for @var{time} is:
155 now|([(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH[:MM[:SS[.m...]]])|(HH[MM[SS[.m...]]]))[Z|z])
157 If the value is "now" it takes the current time.
158 Time is local time unless 'Z' or 'z' is appended, in which case it is
160 If the year-month-day part is not specified it takes the current
163 @item -metadata @var{key}=@var{value}
164 Set a metadata key/value pair.
166 For example, for setting the title in the output file:
168 avconv -i in.avi -metadata title="my title" out.flv
171 @item -v @var{number}
172 Set the logging verbosity level.
174 @item -target @var{type}
175 Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50", "pal-vcd",
176 "ntsc-svcd", ... ). All the format options (bitrate, codecs,
177 buffer sizes) are then set automatically. You can just type:
180 avconv -i myfile.avi -target vcd /tmp/vcd.mpg
183 Nevertheless you can specify additional options as long as you know
184 they do not conflict with the standard, as in:
187 avconv -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
190 @item -dframes @var{number}
191 Set the number of data frames to record.
193 @item -slang @var{code}
194 Set the ISO 639 language code (3 letters) of the current subtitle stream.
198 @section Video Options
201 @item -vframes @var{number}
202 Set the number of video frames to record.
204 Set frame rate (Hz value, fraction or abbreviation), (default = 25).
206 Set frame size. The format is @samp{wxh} (avserver default = 160x128, avconv default = same as source).
207 The following abbreviations are recognized:
269 @item -aspect @var{aspect}
270 Set the video display aspect ratio specified by @var{aspect}.
272 @var{aspect} can be a floating point number string, or a string of the
273 form @var{num}:@var{den}, where @var{num} and @var{den} are the
274 numerator and denominator of the aspect ratio. For example "4:3",
275 "16:9", "1.3333", and "1.7777" are valid argument values.
278 Disable video recording.
279 @item -bt @var{tolerance}
280 Set video bitrate tolerance (in bits, default 4000k).
281 Has a minimum value of: (target_bitrate/target_framerate).
282 In 1-pass mode, bitrate tolerance specifies how far ratecontrol is
283 willing to deviate from the target average bitrate value. This is
284 not related to min/max bitrate. Lowering tolerance too much has
285 an adverse effect on quality.
286 @item -maxrate @var{bitrate}
287 Set max video bitrate (in bit/s).
288 Requires -bufsize to be set.
289 @item -minrate @var{bitrate}
290 Set min video bitrate (in bit/s).
291 Most useful in setting up a CBR encode:
293 avconv -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
295 It is of little use elsewise.
296 @item -bufsize @var{size}
297 Set video buffer verifier buffer size (in bits).
298 @item -vcodec @var{codec}
299 Set the video codec. This is an alias for @code{-codec:v}.
301 Use same quantizer as source (implies VBR).
303 Note that this is NOT SAME QUALITY. Do not use this option unless you know you
307 Select the pass number (1 or 2). It is used to do two-pass
308 video encoding. The statistics of the video are recorded in the first
309 pass into a log file (see also the option -passlogfile),
310 and in the second pass that log file is used to generate the video
311 at the exact requested bitrate.
312 On pass 1, you may just deactivate audio and set output to null,
313 examples for Windows and Unix:
315 avconv -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
316 avconv -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
319 @item -passlogfile @var{prefix}
320 Set two-pass log file name prefix to @var{prefix}, the default file name
321 prefix is ``av2pass''. The complete file name will be
322 @file{PREFIX-N.log}, where N is a number specific to the output
325 @item -vlang @var{code}
326 Set the ISO 639 language code (3 letters) of the current video stream.
328 @item -vf @var{filter_graph}
329 @var{filter_graph} is a description of the filter graph to apply to
331 Use the option "-filters" to show all the available filters (including
332 also sources and sinks).
336 @section Advanced Video Options
339 @item -pix_fmt @var{format}
340 Set pixel format. Use 'list' as parameter to show all the supported
342 @item -sws_flags @var{flags}
344 @item -g @var{gop_size}
345 Set the group of pictures size.
348 @item -qscale @var{q}
349 Use fixed video quantizer scale (VBR).
351 minimum video quantizer scale (VBR)
353 maximum video quantizer scale (VBR)
355 maximum difference between the quantizer scales (VBR)
356 @item -qblur @var{blur}
357 video quantizer scale blur (VBR) (range 0.0 - 1.0)
358 @item -qcomp @var{compression}
359 video quantizer scale compression (VBR) (default 0.5).
360 Constant of ratecontrol equation. Recommended range for default rc_eq: 0.0-1.0
362 @item -lmin @var{lambda}
363 minimum video lagrange factor (VBR)
364 @item -lmax @var{lambda}
365 max video lagrange factor (VBR)
366 @item -mblmin @var{lambda}
367 minimum macroblock quantizer scale (VBR)
368 @item -mblmax @var{lambda}
369 maximum macroblock quantizer scale (VBR)
371 These four options (lmin, lmax, mblmin, mblmax) use 'lambda' units,
372 but you may use the QP2LAMBDA constant to easily convert from 'q' units:
374 avconv -i src.ext -lmax 21*QP2LAMBDA dst.ext
377 @item -rc_init_cplx @var{complexity}
378 initial complexity for single pass encoding
379 @item -b_qfactor @var{factor}
380 qp factor between P- and B-frames
381 @item -i_qfactor @var{factor}
382 qp factor between P- and I-frames
383 @item -b_qoffset @var{offset}
384 qp offset between P- and B-frames
385 @item -i_qoffset @var{offset}
386 qp offset between P- and I-frames
387 @item -rc_eq @var{equation}
388 Set rate control equation (see section "Expression Evaluation")
389 (default = @code{tex^qComp}).
391 When computing the rate control equation expression, besides the
392 standard functions defined in the section "Expression Evaluation", the
393 following functions are available:
399 and the following constants are available:
421 @item -rc_override @var{override}
422 rate control override for specific intervals
423 @item -me_method @var{method}
424 Set motion estimation method to @var{method}.
425 Available methods are (from lowest to best quality):
428 Try just the (0, 0) vector.
437 exhaustive search (slow and marginally better than epzs)
440 @item -dct_algo @var{algo}
441 Set DCT algorithm to @var{algo}. Available values are:
444 FF_DCT_AUTO (default)
457 @item -idct_algo @var{algo}
458 Set IDCT algorithm to @var{algo}. Available values are:
461 FF_IDCT_AUTO (default)
485 Set error resilience to @var{n}.
488 FF_ER_CAREFUL (default)
494 FF_ER_VERY_AGGRESSIVE
497 @item -ec @var{bit_mask}
498 Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of
499 the following values:
502 FF_EC_GUESS_MVS (default = enabled)
504 FF_EC_DEBLOCK (default = enabled)
507 @item -bf @var{frames}
508 Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4).
509 @item -mbd @var{mode}
513 FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in avconv).
515 FF_MB_DECISION_BITS: Choose the one which needs the fewest bits.
517 FF_MB_DECISION_RD: rate distortion
521 Use four motion vector by macroblock (MPEG-4 only).
523 Use data partitioning (MPEG-4 only).
524 @item -bug @var{param}
525 Work around encoder bugs that are not auto-detected.
526 @item -strict @var{strictness}
527 How strictly to follow the standards.
529 Enable Advanced intra coding (h263+).
531 Enable Unlimited Motion Vector (h263+)
534 Deinterlace pictures.
536 Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
537 Use this option if your input file is interlaced and you want
538 to keep the interlaced format for minimum losses.
539 The alternative is to deinterlace the input stream with
540 @option{-deinterlace}, but deinterlacing introduces losses.
542 Calculate PSNR of compressed frames.
544 Dump video coding statistics to @file{vstats_HHMMSS.log}.
545 @item -vstats_file @var{file}
546 Dump video coding statistics to @var{file}.
548 top=1/bottom=0/auto=-1 field first
549 @item -dc @var{precision}
551 @item -vtag @var{fourcc/tag}
552 Force video tag/fourcc.
555 @item -vbsf @var{bitstream_filter}
556 Bitstream filters available are "dump_extra", "remove_extra", "noise", "h264_mp4toannexb", "imxdump", "mjpegadump", "mjpeg2jpeg".
558 avconv -i h264.mp4 -c:v copy -vbsf h264_mp4toannexb -an out.h264
560 @item -force_key_frames @var{time}[,@var{time}...]
561 Force key frames at the specified timestamps, more precisely at the first
562 frames after each specified time.
563 This option can be useful to ensure that a seek point is present at a
564 chapter mark or any other designated place in the output file.
565 The timestamps must be specified in ascending order.
568 @section Audio Options
571 @item -aframes @var{number}
572 Set the number of audio frames to record.
574 Set the audio sampling frequency. For output streams it is set by
575 default to the frequency of the corresponding input stream. For input
576 streams this option only makes sense for audio grabbing devices and raw
577 demuxers and is mapped to the corresponding demuxer options.
579 Set the audio quality (codec-specific, VBR).
580 @item -ac @var{channels}
581 Set the number of audio channels. For output streams it is set by
582 default to the number of input audio channels. For input streams
583 this option only makes sense for audio grabbing devices and raw demuxers
584 and is mapped to the corresponding demuxer options.
586 Disable audio recording.
587 @item -acodec @var{codec}
588 Set the audio codec. This is an alias for @code{-codec:a}.
589 @item -alang @var{code}
590 Set the ISO 639 language code (3 letters) of the current audio stream.
593 @section Advanced Audio options:
596 @item -atag @var{fourcc/tag}
597 Force audio tag/fourcc.
598 @item -audio_service_type @var{type}
599 Set the type of service that the audio stream contains.
602 Main Audio Service (default)
620 @item -absf @var{bitstream_filter}
621 Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp".
624 @section Subtitle options:
627 @item -scodec @var{codec}
628 Set the subtitle codec. This is an alias for @code{-codec:s}.
629 @item -slang @var{code}
630 Set the ISO 639 language code (3 letters) of the current subtitle stream.
632 Disable subtitle recording.
633 @item -sbsf @var{bitstream_filter}
634 Bitstream filters available are "mov2textsub", "text2movsub".
636 avconv -i file.mov -an -vn -sbsf mov2textsub -c:s copy -f rawvideo sub.txt
640 @section Audio/Video grab options
644 Synchronize read on input.
647 @section Advanced options
650 @item -map [-]@var{input_file_id}[:@var{input_stream_type}][:@var{input_stream_id}][,@var{sync_file_id}[:@var{sync_stream_type}][:@var{sync_stream_id}]]
652 Designate one or more input streams as a source for the output file. Each input
653 stream is identified by the input file index @var{input_file_id} and
654 the input stream index @var{input_stream_id} within the input
655 file. Both indices start at 0. If specified,
656 @var{sync_file_id}:@var{sync_stream_id} sets which input stream
657 is used as a presentation sync reference.
659 If @var{input_stream_type} is specified -- 'v' for video, 'a' for audio, 's' for
660 subtitle and 'd' for data -- then @var{input_stream_id} counts only the streams
661 of this type. Same for @var{sync_stream_type}.
663 @var{input_stream_id} may be omitted, in which case all streams of the given
664 type are mapped (or all streams in the file, if no type is specified).
666 The first @code{-map} option on the command line specifies the
667 source for output stream 0, the second @code{-map} option specifies
668 the source for output stream 1, etc.
670 A @code{-} character before the stream identifier creates a "negative" mapping.
671 It disables matching streams from already created mappings.
673 For example, to map ALL streams from the first input file to output
675 avconv -i INPUT -map 0 output
678 For example, if you have two audio streams in the first input file,
679 these streams are identified by "0:0" and "0:1". You can use
680 @code{-map} to select which streams to place in an output file. For
683 avconv -i INPUT -map 0:1 out.wav
685 will map the input stream in @file{INPUT} identified by "0:1" to
686 the (single) output stream in @file{out.wav}.
688 For example, to select the stream with index 2 from input file
689 @file{a.mov} (specified by the identifier "0:2"), and stream with
690 index 6 from input @file{b.mov} (specified by the identifier "1:6"),
691 and copy them to the output file @file{out.mov}:
693 avconv -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
696 To select all video and the third audio stream from an input file:
698 avconv -i INPUT -map 0:v -map 0:a:2 OUTPUT
701 To map all the streams except the second audio, use negative mappings
703 avconv -i INPUT -map 0 -map -0:a:1 OUTPUT
706 Note that using this option disables the default mappings for this output file.
708 @item -map_metadata[:@var{metadata_type}][:@var{index}] @var{infile}[:@var{metadata_type}][:@var{index}]
709 Set metadata information of the next output file from @var{infile}. Note that
710 those are file indices (zero-based), not filenames.
711 Optional @var{metadata_type} parameters specify, which metadata to copy - (g)lobal
712 (i.e. metadata that applies to the whole file), per-(s)tream, per-(c)hapter or
713 per-(p)rogram. All metadata specifiers other than global must be followed by the
714 stream/chapter/program index. If metadata specifier is omitted, it defaults to
717 By default, global metadata is copied from the first input file,
718 per-stream and per-chapter metadata is copied along with streams/chapters. These
719 default mappings are disabled by creating any mapping of the relevant type. A negative
720 file index can be used to create a dummy mapping that just disables automatic copying.
722 For example to copy metadata from the first stream of the input file to global metadata
725 avconv -i in.ogg -map_metadata 0:s:0 out.mp3
727 @item -map_chapters @var{input_file_index}
728 Copy chapters from input file with index @var{input_file_index} to the next
729 output file. If no chapter mapping is specified, then chapters are copied from
730 the first input file with at least one chapter. Use a negative file index to
731 disable any chapter copying.
733 Print specific debug info.
735 Show benchmarking information at the end of an encode.
736 Shows CPU time used and maximum memory consumption.
737 Maximum memory consumption is not supported on all systems,
738 it will usually display as 0 if not supported.
740 Dump each input packet.
742 When dumping packets, also dump the payload.
744 Only use bit exact algorithms (for codec testing).
746 Set RTP payload size in bytes.
748 Read input at native frame rate. Mainly used to simulate a grab device.
749 @item -threads @var{count}
751 @item -vsync @var{parameter}
756 Each frame is passed with its timestamp from the demuxer to the muxer.
758 Frames will be duplicated and dropped to achieve exactly the requested
761 Frames are passed through with their timestamp or dropped so as to
762 prevent 2 frames from having the same timestamp.
764 Chooses between 1 and 2 depending on muxer capabilities. This is the
768 With -map you can select from which stream the timestamps should be
769 taken. You can leave either video or audio unchanged and sync the
770 remaining stream(s) to the unchanged one.
772 @item -async @var{samples_per_second}
773 Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
774 the parameter is the maximum samples per second by which the audio is changed.
775 -async 1 is a special case where only the start of the audio stream is corrected
776 without any later correction.
778 Copy timestamps from input to output.
780 Copy input stream time base from input to output when stream copying.
782 Finish encoding when the shortest input stream ends.
783 @item -dts_delta_threshold
784 Timestamp discontinuity delta threshold.
785 @item -muxdelay @var{seconds}
786 Set the maximum demux-decode delay.
787 @item -muxpreload @var{seconds}
788 Set the initial demux-decode delay.
789 @item -streamid @var{output-stream-index}:@var{new-value}
790 Assign a new stream-id value to an output stream. This option should be
791 specified prior to the output filename to which it applies.
792 For the situation where multiple output files exist, a streamid
793 may be reassigned to a different value.
795 For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
796 an output mpegts file:
798 avconv -i infile -streamid 0:33 -streamid 1:36 out.ts
808 For streaming at very low bitrate application, use a low frame rate
809 and a small GOP size. This is especially true for RealVideo where
810 the Linux player does not seem to be very fast, so it can miss
811 frames. An example is:
814 avconv -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
818 The parameter 'q' which is displayed while encoding is the current
819 quantizer. The value 1 indicates that a very good quality could
820 be achieved. The value 31 indicates the worst quality. If q=31 appears
821 too often, it means that the encoder cannot compress enough to meet
822 your bitrate. You must either increase the bitrate, decrease the
823 frame rate or decrease the frame size.
826 If your computer is not fast enough, you can speed up the
827 compression at the expense of the compression ratio. You can use
828 '-me zero' to speed up motion estimation, and '-intra' to disable
829 motion estimation completely (you have only I-frames, which means it
830 is about as good as JPEG compression).
833 To have very low audio bitrates, reduce the sampling frequency
834 (down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
837 To have a constant quality (but a variable bitrate), use the option
838 '-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
845 @c man begin EXAMPLES
847 @section Video and Audio grabbing
849 If you specify the input format and device then avconv can grab video
853 avconv -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
856 Note that you must activate the right video source and channel before
857 launching avconv with any TV viewer such as
858 @uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
859 have to set the audio recording levels correctly with a
862 @section X11 grabbing
864 Grab the X11 display with avconv via
867 avconv -f x11grab -s cif -r 25 -i :0.0 /tmp/out.mpg
870 0.0 is display.screen number of your X11 server, same as
871 the DISPLAY environment variable.
874 avconv -f x11grab -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg
877 0.0 is display.screen number of your X11 server, same as the DISPLAY environment
878 variable. 10 is the x-offset and 20 the y-offset for the grabbing.
880 @section Video and Audio file format conversion
882 Any supported file format and protocol can serve as input to avconv:
887 You can use YUV files as input:
890 avconv -i /tmp/test%d.Y /tmp/out.mpg
893 It will use the files:
895 /tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
896 /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
899 The Y files use twice the resolution of the U and V files. They are
900 raw files, without header. They can be generated by all decent video
901 decoders. You must specify the size of the image with the @option{-s} option
902 if avconv cannot guess it.
905 You can input from a raw YUV420P file:
908 avconv -i /tmp/test.yuv /tmp/out.avi
911 test.yuv is a file containing raw YUV planar data. Each frame is composed
912 of the Y plane followed by the U and V planes at half vertical and
913 horizontal resolution.
916 You can output to a raw YUV420P file:
919 avconv -i mydivx.avi hugefile.yuv
923 You can set several input files and output files:
926 avconv -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
929 Converts the audio file a.wav and the raw YUV video file a.yuv
933 You can also do audio and video conversions at the same time:
936 avconv -i /tmp/a.wav -ar 22050 /tmp/a.mp2
939 Converts a.wav to MPEG audio at 22050 Hz sample rate.
942 You can encode to several formats at the same time and define a
943 mapping from input stream to output streams:
946 avconv -i /tmp/a.wav -map 0:a -b 64k /tmp/a.mp2 -map 0:a -b 128k /tmp/b.mp2
949 Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
950 file:index' specifies which input stream is used for each output
951 stream, in the order of the definition of output streams.
954 You can transcode decrypted VOBs:
957 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
960 This is a typical DVD ripping example; the input is a VOB file, the
961 output an AVI file with MPEG-4 video and MP3 audio. Note that in this
962 command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
963 GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
964 input video. Furthermore, the audio stream is MP3-encoded so you need
965 to enable LAME support by passing @code{--enable-libmp3lame} to configure.
966 The mapping is particularly useful for DVD transcoding
967 to get the desired audio language.
969 NOTE: To see the supported input formats, use @code{avconv -formats}.
972 You can extract images from a video, or create a video from many images:
974 For extracting images from a video:
976 avconv -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
979 This will extract one video frame per second from the video and will
980 output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
981 etc. Images will be rescaled to fit the new WxH values.
983 If you want to extract just a limited number of frames, you can use the
984 above command in combination with the -vframes or -t option, or in
985 combination with -ss to start extracting from a certain point in time.
987 For creating a video from many images:
989 avconv -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
992 The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
993 composed of three digits padded with zeroes to express the sequence
994 number. It is the same syntax supported by the C printf function, but
995 only formats accepting a normal integer are suitable.
998 You can put many streams of the same type in the output:
1001 avconv -i test1.avi -i test2.avi -map 0.3 -map 0.2 -map 0.1 -map 0.0 -c copy test12.nut
1004 The resulting output file @file{test12.avi} will contain first four streams from
1005 the input file in reverse order.
1011 @include encoders.texi
1012 @include demuxers.texi
1013 @include muxers.texi
1014 @include indevs.texi
1015 @include outdevs.texi
1016 @include protocols.texi
1017 @include bitstream_filters.texi
1018 @include filters.texi
1019 @include metadata.texi
1024 @settitle avconv video converter
1026 @c man begin SEEALSO
1027 avplay(1), avprobe(1), avserver(1) and the Libav HTML documentation
1030 @c man begin AUTHORS
1031 The Libav developers