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diff --git a/doc/avconv.texi b/doc/avconv.texi deleted file mode 100644 index 85c1457621..0000000000 --- a/doc/avconv.texi +++ /dev/null @@ -1,1063 +0,0 @@ -\input texinfo @c -*- texinfo -*- - -@settitle avconv Documentation -@titlepage -@center @titlefont{avconv Documentation} -@end titlepage - -@top - -@contents - -@chapter Synopsis - -The generic syntax is: - -@example -@c man begin SYNOPSIS -avconv [global options] [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}... -@c man end -@end example - -@chapter Description -@c man begin DESCRIPTION - -avconv is a very fast video and audio converter that can also grab from -a live audio/video source. It can also convert between arbitrary sample -rates and resize video on the fly with a high quality polyphase filter. - -avconv reads from an arbitrary number of input "files" (which can be regular -files, pipes, network streams, grabbing devices, etc.), specified by the -@code{-i} option, and writes to an arbitrary number of output "files", which are -specified by a plain output filename. Anything found on the command line which -cannot be interpreted as an option is considered to be an output filename. - -Each input or output file can in principle contain any number of streams of -different types (video/audio/subtitle/attachment/data). Allowed number and/or -types of streams can be limited by the container format. Selecting, which -streams from which inputs go into output, is done either automatically or with -the @code{-map} option (see the Stream selection chapter). - -To refer to input files in options, you must use their indices (0-based). E.g. -the first input file is @code{0}, the second is @code{1} etc. Similarly, streams -within a file are referred to by their indices. E.g. @code{2:3} refers to the -fourth stream in the third input file. See also the Stream specifiers chapter. - -As a general rule, options are applied to the next specified -file. Therefore, order is important, and you can have the same -option on the command line multiple times. Each occurrence is -then applied to the next input or output file. -Exceptions from this rule are the global options (e.g. verbosity level), -which should be specified first. - -Do not mix input and output files -- first specify all input files, then all -output files. Also do not mix options which belong to different files. All -options apply ONLY to the next input or output file and are reset between files. - -@itemize -@item -To set the video bitrate of the output file to 64kbit/s: -@example -avconv -i input.avi -b 64k output.avi -@end example - -@item -To force the frame rate of the output file to 24 fps: -@example -avconv -i input.avi -r 24 output.avi -@end example - -@item -To force the frame rate of the input file (valid for raw formats only) -to 1 fps and the frame rate of the output file to 24 fps: -@example -avconv -r 1 -i input.m2v -r 24 output.avi -@end example -@end itemize - -The format option may be needed for raw input files. - -@c man end DESCRIPTION - -@chapter Stream selection -@c man begin STREAM SELECTION - -By default avconv tries to pick the "best" stream of each type present in input -files and add them to each output file. For video, this means the highest -resolution, for audio the highest channel count. For subtitle it's simply the -first subtitle stream. - -You can disable some of those defaults by using @code{-vn/-an/-sn} options. For -full manual control, use the @code{-map} option, which disables the defaults just -described. - -@c man end STREAM SELECTION - -@chapter Options -@c man begin OPTIONS - -@include avtools-common-opts.texi - -@section Main options - -@table @option - -@item -f @var{fmt} (@emph{input/output}) -Force input or output file format. The format is normally autodetected for input -files and guessed from file extension for output files, so this option is not -needed in most cases. - -@item -i @var{filename} (@emph{input}) -input file name - -@item -y (@emph{global}) -Overwrite output files without asking. - -@item -n (@emph{global}) -Do not overwrite output files but exit if file exists. - -@item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream}) -@itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream}) -Select an encoder (when used before an output file) or a decoder (when used -before an input file) for one or more streams. @var{codec} is the name of a -decoder/encoder or a special value @code{copy} (output only) to indicate that -the stream is not to be reencoded. - -For example -@example -avconv -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT -@end example -encodes all video streams with libx264 and copies all audio streams. - -For each stream, the last matching @code{c} option is applied, so -@example -avconv -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT -@end example -will copy all the streams except the second video, which will be encoded with -libx264, and the 138th audio, which will be encoded with libvorbis. - -@item -t @var{duration} (@emph{output}) -Stop writing the output after its duration reaches @var{duration}. -@var{duration} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form. - -@item -fs @var{limit_size} (@emph{output}) -Set the file size limit. - -@item -ss @var{position} (@emph{input/output}) -When used as an input option (before @code{-i}), seeks in this input file to -@var{position}. When used as an output option (before an output filename), -decodes but discards input until the timestamps reach @var{position}. This is -slower, but more accurate. - -@var{position} may be either in seconds or in @code{hh:mm:ss[.xxx]} form. - -@item -itsoffset @var{offset} (@emph{input}) -Set the input time offset in seconds. -@code{[-]hh:mm:ss[.xxx]} syntax is also supported. -The offset is added to the timestamps of the input files. -Specifying a positive offset means that the corresponding -streams are delayed by @var{offset} seconds. - -@item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata}) -Set a metadata key/value pair. - -An optional @var{metadata_specifier} may be given to set metadata -on streams or chapters. See @code{-map_metadata} documentation for -details. - -This option overrides metadata set with @code{-map_metadata}. It is -also possible to delete metadata by using an empty value. - -For example, for setting the title in the output file: -@example -avconv -i in.avi -metadata title="my title" out.flv -@end example - -To set the language of the first audio stream: -@example -avconv -i INPUT -metadata:s:a:0 language=eng OUTPUT -@end example - -@item -target @var{type} (@emph{output}) -Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv}, -@code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or -@code{film-} to use the corresponding standard. All the format options -(bitrate, codecs, buffer sizes) are then set automatically. You can just type: - -@example -avconv -i myfile.avi -target vcd /tmp/vcd.mpg -@end example - -Nevertheless you can specify additional options as long as you know -they do not conflict with the standard, as in: - -@example -avconv -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg -@end example - -@item -dframes @var{number} (@emph{output}) -Set the number of data frames to record. This is an alias for @code{-frames:d}. - -@item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream}) -Stop writing to the stream after @var{framecount} frames. - -@item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream}) -@itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream}) -Use fixed quality scale (VBR). The meaning of @var{q} is -codec-dependent. - -@item -filter[:@var{stream_specifier}] @var{filter_graph} (@emph{output,per-stream}) -@var{filter_graph} is a description of the filter graph to apply to -the stream. Use @code{-filters} to show all the available filters -(including also sources and sinks). -@item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream}) -Specify the preset for matching stream(s). - -@item -stats (@emph{global}) -Print encoding progress/statistics. On by default. - -@item -attach @var{filename} (@emph{output}) -Add an attachment to the output file. This is supported by a few formats -like Matroska for e.g. fonts used in rendering subtitles. Attachments -are implemented as a specific type of stream, so this option will add -a new stream to the file. It is then possible to use per-stream options -on this stream in the usual way. Attachment streams created with this -option will be created after all the other streams (i.e. those created -with @code{-map} or automatic mappings). - -Note that for Matroska you also have to set the mimetype metadata tag: -@example -avconv -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv -@end example -(assuming that the attachment stream will be third in the output file). - -@item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream}) -Extract the matching attachment stream into a file named @var{filename}. If -@var{filename} is empty, then the value of the @code{filename} metadata tag -will be used. - -E.g. to extract the first attachment to a file named 'out.ttf': -@example -avconv -dump_attachment:t:0 out.ttf INPUT -@end example -To extract all attachments to files determined by the @code{filename} tag: -@example -avconv -dump_attachment:t "" INPUT -@end example - -Technical note -- attachments are implemented as codec extradata, so this -option can actually be used to extract extradata from any stream, not just -attachments. - -@end table - -@section Video Options - -@table @option -@item -vframes @var{number} (@emph{output}) -Set the number of video frames to record. This is an alias for @code{-frames:v}. -@item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream}) -Set frame rate (Hz value, fraction or abbreviation), (default = 25). -@item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream}) -Set frame size. The format is @samp{wxh} (default - same as source). -The following abbreviations are recognized: -@table @samp -@item sqcif -128x96 -@item qcif -176x144 -@item cif -352x288 -@item 4cif -704x576 -@item 16cif -1408x1152 -@item qqvga -160x120 -@item qvga -320x240 -@item vga -640x480 -@item svga -800x600 -@item xga -1024x768 -@item uxga -1600x1200 -@item qxga -2048x1536 -@item sxga -1280x1024 -@item qsxga -2560x2048 -@item hsxga -5120x4096 -@item wvga -852x480 -@item wxga -1366x768 -@item wsxga -1600x1024 -@item wuxga -1920x1200 -@item woxga -2560x1600 -@item wqsxga -3200x2048 -@item wquxga -3840x2400 -@item whsxga -6400x4096 -@item whuxga -7680x4800 -@item cga -320x200 -@item ega -640x350 -@item hd480 -852x480 -@item hd720 -1280x720 -@item hd1080 -1920x1080 -@end table - -@item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream}) -Set the video display aspect ratio specified by @var{aspect}. - -@var{aspect} can be a floating point number string, or a string of the -form @var{num}:@var{den}, where @var{num} and @var{den} are the -numerator and denominator of the aspect ratio. For example "4:3", -"16:9", "1.3333", and "1.7777" are valid argument values. - -@item -vn (@emph{output}) -Disable video recording. -@item -bt @var{tolerance} -Set video bitrate tolerance (in bits, default 4000k). -Has a minimum value of: (target_bitrate/target_framerate). -In 1-pass mode, bitrate tolerance specifies how far ratecontrol is -willing to deviate from the target average bitrate value. This is -not related to min/max bitrate. Lowering tolerance too much has -an adverse effect on quality. -@item -maxrate @var{bitrate} -Set max video bitrate (in bit/s). -Requires -bufsize to be set. -@item -minrate @var{bitrate} -Set min video bitrate (in bit/s). -Most useful in setting up a CBR encode: -@example -avconv -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v -@end example -It is of little use elsewise. -@item -bufsize @var{size} -Set video buffer verifier buffer size (in bits). -@item -vcodec @var{codec} (@emph{output}) -Set the video codec. This is an alias for @code{-codec:v}. -@item -same_quant -Use same quantizer as source (implies VBR). - -Note that this is NOT SAME QUALITY. Do not use this option unless you know you -need it. - -@item -pass @var{n} -Select the pass number (1 or 2). It is used to do two-pass -video encoding. The statistics of the video are recorded in the first -pass into a log file (see also the option -passlogfile), -and in the second pass that log file is used to generate the video -at the exact requested bitrate. -On pass 1, you may just deactivate audio and set output to null, -examples for Windows and Unix: -@example -avconv -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL -avconv -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null -@end example - -@item -passlogfile @var{prefix} (@emph{global}) -Set two-pass log file name prefix to @var{prefix}, the default file name -prefix is ``av2pass''. The complete file name will be -@file{PREFIX-N.log}, where N is a number specific to the output -stream. - -@item -vf @var{filter_graph} (@emph{output}) -@var{filter_graph} is a description of the filter graph to apply to -the input video. -Use the option "-filters" to show all the available filters (including -also sources and sinks). This is an alias for @code{-filter:v}. - -@end table - -@section Advanced Video Options - -@table @option -@item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream}) -Set pixel format. Use @code{-pix_fmts} to show all the supported -pixel formats. -@item -sws_flags @var{flags} (@emph{input/output}) -Set SwScaler flags. -@item -g @var{gop_size} -Set the group of pictures size. -@item -vdt @var{n} -Discard threshold. -@item -qmin @var{q} -minimum video quantizer scale (VBR) -@item -qmax @var{q} -maximum video quantizer scale (VBR) -@item -qdiff @var{q} -maximum difference between the quantizer scales (VBR) -@item -qblur @var{blur} -video quantizer scale blur (VBR) (range 0.0 - 1.0) -@item -qcomp @var{compression} -video quantizer scale compression (VBR) (default 0.5). -Constant of ratecontrol equation. Recommended range for default rc_eq: 0.0-1.0 - -@item -lmin @var{lambda} -minimum video lagrange factor (VBR) -@item -lmax @var{lambda} -max video lagrange factor (VBR) -@item -mblmin @var{lambda} -minimum macroblock quantizer scale (VBR) -@item -mblmax @var{lambda} -maximum macroblock quantizer scale (VBR) - -These four options (lmin, lmax, mblmin, mblmax) use 'lambda' units, -but you may use the QP2LAMBDA constant to easily convert from 'q' units: -@example -avconv -i src.ext -lmax 21*QP2LAMBDA dst.ext -@end example - -@item -rc_init_cplx @var{complexity} -initial complexity for single pass encoding -@item -b_qfactor @var{factor} -qp factor between P- and B-frames -@item -i_qfactor @var{factor} -qp factor between P- and I-frames -@item -b_qoffset @var{offset} -qp offset between P- and B-frames -@item -i_qoffset @var{offset} -qp offset between P- and I-frames -@item -rc_eq @var{equation} -Set rate control equation (see section "Expression Evaluation") -(default = @code{tex^qComp}). - -When computing the rate control equation expression, besides the -standard functions defined in the section "Expression Evaluation", the -following functions are available: -@table @var -@item bits2qp(bits) -@item qp2bits(qp) -@end table - -and the following constants are available: -@table @var -@item iTex -@item pTex -@item tex -@item mv -@item fCode -@item iCount -@item mcVar -@item var -@item isI -@item isP -@item isB -@item avgQP -@item qComp -@item avgIITex -@item avgPITex -@item avgPPTex -@item avgBPTex -@item avgTex -@end table - -@item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream}) -rate control override for specific intervals -@item -me_method @var{method} -Set motion estimation method to @var{method}. -Available methods are (from lowest to best quality): -@table @samp -@item zero -Try just the (0, 0) vector. -@item phods -@item log -@item x1 -@item hex -@item umh -@item epzs -(default method) -@item full -exhaustive search (slow and marginally better than epzs) -@end table - -@item -er @var{n} -Set error resilience to @var{n}. -@table @samp -@item 1 -FF_ER_CAREFUL (default) -@item 2 -FF_ER_COMPLIANT -@item 3 -FF_ER_AGGRESSIVE -@item 4 -FF_ER_VERY_AGGRESSIVE -@end table - -@item -ec @var{bit_mask} -Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of -the following values: -@table @samp -@item 1 -FF_EC_GUESS_MVS (default = enabled) -@item 2 -FF_EC_DEBLOCK (default = enabled) -@end table - -@item -bf @var{frames} -Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4). -@item -mbd @var{mode} -macroblock decision -@table @samp -@item 0 -FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in avconv). -@item 1 -FF_MB_DECISION_BITS: Choose the one which needs the fewest bits. -@item 2 -FF_MB_DECISION_RD: rate distortion -@end table - -@item -bug @var{param} -Work around encoder bugs that are not auto-detected. -@item -strict @var{strictness} -How strictly to follow the standards. - -@item -deinterlace -Deinterlace pictures. -@item -vstats -Dump video coding statistics to @file{vstats_HHMMSS.log}. -@item -vstats_file @var{file} -Dump video coding statistics to @var{file}. -@item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream}) -top=1/bottom=0/auto=-1 field first -@item -dc @var{precision} -Intra_dc_precision. -@item -vtag @var{fourcc/tag} (@emph{output}) -Force video tag/fourcc. This is an alias for @code{-tag:v}. -@item -qphist (@emph{global}) -Show QP histogram. -@item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream}) -Force key frames at the specified timestamps, more precisely at the first -frames after each specified time. -This option can be useful to ensure that a seek point is present at a -chapter mark or any other designated place in the output file. -The timestamps must be specified in ascending order. - -@item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream}) -When doing stream copy, copy also non-key frames found at the -beginning. -@end table - -@section Audio Options - -@table @option -@item -aframes @var{number} (@emph{output}) -Set the number of audio frames to record. This is an alias for @code{-frames:a}. -@item -ar[:@var{stream_specifier}] @var{freq} (@emph{input/output,per-stream}) -Set the audio sampling frequency. For output streams it is set by -default to the frequency of the corresponding input stream. For input -streams this option only makes sense for audio grabbing devices and raw -demuxers and is mapped to the corresponding demuxer options. -@item -aq @var{q} (@emph{output}) -Set the audio quality (codec-specific, VBR). This is an alias for -q:a. -@item -ac[:@var{stream_specifier}] @var{channels} (@emph{input/output,per-stream}) -Set the number of audio channels. For output streams it is set by -default to the number of input audio channels. For input streams -this option only makes sense for audio grabbing devices and raw demuxers -and is mapped to the corresponding demuxer options. -@item -an (@emph{output}) -Disable audio recording. -@item -acodec @var{codec} (@emph{input/output}) -Set the audio codec. This is an alias for @code{-codec:a}. -@item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream}) -Set the audio sample format. Use @code{-sample_fmts} to get a list -of supported sample formats. -@end table - -@section Advanced Audio options: - -@table @option -@item -atag @var{fourcc/tag} (@emph{output}) -Force audio tag/fourcc. This is an alias for @code{-tag:a}. -@item -audio_service_type @var{type} -Set the type of service that the audio stream contains. -@table @option -@item ma -Main Audio Service (default) -@item ef -Effects -@item vi -Visually Impaired -@item hi -Hearing Impaired -@item di -Dialogue -@item co -Commentary -@item em -Emergency -@item vo -Voice Over -@item ka -Karaoke -@end table -@end table - -@section Subtitle options: - -@table @option -@item -scodec @var{codec} (@emph{input/output}) -Set the subtitle codec. This is an alias for @code{-codec:s}. -@item -sn (@emph{output}) -Disable subtitle recording. -@end table - -@section Audio/Video grab options - -@table @option -@item -isync (@emph{global}) -Synchronize read on input. -@end table - -@section Advanced options - -@table @option -@item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] (@emph{output}) - -Designate one or more input streams as a source for the output file. Each input -stream is identified by the input file index @var{input_file_id} and -the input stream index @var{input_stream_id} within the input -file. Both indices start at 0. If specified, -@var{sync_file_id}:@var{stream_specifier} sets which input stream -is used as a presentation sync reference. - -The first @code{-map} option on the command line specifies the -source for output stream 0, the second @code{-map} option specifies -the source for output stream 1, etc. - -A @code{-} character before the stream identifier creates a "negative" mapping. -It disables matching streams from already created mappings. - -For example, to map ALL streams from the first input file to output -@example -avconv -i INPUT -map 0 output -@end example - -For example, if you have two audio streams in the first input file, -these streams are identified by "0:0" and "0:1". You can use -@code{-map} to select which streams to place in an output file. For -example: -@example -avconv -i INPUT -map 0:1 out.wav -@end example -will map the input stream in @file{INPUT} identified by "0:1" to -the (single) output stream in @file{out.wav}. - -For example, to select the stream with index 2 from input file -@file{a.mov} (specified by the identifier "0:2"), and stream with -index 6 from input @file{b.mov} (specified by the identifier "1:6"), -and copy them to the output file @file{out.mov}: -@example -avconv -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov -@end example - -To select all video and the third audio stream from an input file: -@example -avconv -i INPUT -map 0:v -map 0:a:2 OUTPUT -@end example - -To map all the streams except the second audio, use negative mappings -@example -avconv -i INPUT -map 0 -map -0:a:1 OUTPUT -@end example - -Note that using this option disables the default mappings for this output file. - -@item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata}) -Set metadata information of the next output file from @var{infile}. Note that -those are file indices (zero-based), not filenames. -Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy. -A metadata specifier can have the following forms: -@table @option -@item @var{g} -global metadata, i.e. metadata that applies to the whole file - -@item @var{s}[:@var{stream_spec}] -per-stream metadata. @var{stream_spec} is a stream specifier as described -in the @ref{Stream specifiers} chapter. In an input metadata specifier, the first -matching stream is copied from. In an output metadata specifier, all matching -streams are copied to. - -@item @var{c}:@var{chapter_index} -per-chapter metadata. @var{chapter_index} is the zero-based chapter index. - -@item @var{p}:@var{program_index} -per-program metadata. @var{program_index} is the zero-based program index. -@end table -If metadata specifier is omitted, it defaults to global. - -By default, global metadata is copied from the first input file, -per-stream and per-chapter metadata is copied along with streams/chapters. These -default mappings are disabled by creating any mapping of the relevant type. A negative -file index can be used to create a dummy mapping that just disables automatic copying. - -For example to copy metadata from the first stream of the input file to global metadata -of the output file: -@example -avconv -i in.ogg -map_metadata 0:s:0 out.mp3 -@end example - -To do the reverse, i.e. copy global metadata to all audio streams: -@example -avconv -i in.mkv -map_metadata:s:a 0:g out.mkv -@end example -Note that simple @code{0} would work as well in this example, since global -metadata is assumed by default. - -@item -map_chapters @var{input_file_index} (@emph{output}) -Copy chapters from input file with index @var{input_file_index} to the next -output file. If no chapter mapping is specified, then chapters are copied from -the first input file with at least one chapter. Use a negative file index to -disable any chapter copying. -@item -debug -Print specific debug info. -@item -benchmark (@emph{global}) -Show benchmarking information at the end of an encode. -Shows CPU time used and maximum memory consumption. -Maximum memory consumption is not supported on all systems, -it will usually display as 0 if not supported. -@item -timelimit @var{duration} (@emph{global}) -Exit after avconv has been running for @var{duration} seconds. -@item -dump (@emph{global}) -Dump each input packet to stderr. -@item -hex (@emph{global}) -When dumping packets, also dump the payload. -@item -ps @var{size} -Set RTP payload size in bytes. -@item -re (@emph{input}) -Read input at native frame rate. Mainly used to simulate a grab device. -@item -threads @var{count} -Thread count. -@item -vsync @var{parameter} -Video sync method. - -@table @option -@item passthrough -Each frame is passed with its timestamp from the demuxer to the muxer. -@item cfr -Frames will be duplicated and dropped to achieve exactly the requested -constant framerate. -@item vfr -Frames are passed through with their timestamp or dropped so as to -prevent 2 frames from having the same timestamp. -@item auto -Chooses between 1 and 2 depending on muxer capabilities. This is the -default method. -@end table - -With -map you can select from which stream the timestamps should be -taken. You can leave either video or audio unchanged and sync the -remaining stream(s) to the unchanged one. - -@item -async @var{samples_per_second} -Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps, -the parameter is the maximum samples per second by which the audio is changed. --async 1 is a special case where only the start of the audio stream is corrected -without any later correction. -@item -copyts -Copy timestamps from input to output. -@item -copytb -Copy input stream time base from input to output when stream copying. -@item -shortest -Finish encoding when the shortest input stream ends. -@item -dts_delta_threshold -Timestamp discontinuity delta threshold. -@item -muxdelay @var{seconds} (@emph{input}) -Set the maximum demux-decode delay. -@item -muxpreload @var{seconds} (@emph{input}) -Set the initial demux-decode delay. -@item -streamid @var{output-stream-index}:@var{new-value} (@emph{output}) -Assign a new stream-id value to an output stream. This option should be -specified prior to the output filename to which it applies. -For the situation where multiple output files exist, a streamid -may be reassigned to a different value. - -For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for -an output mpegts file: -@example -avconv -i infile -streamid 0:33 -streamid 1:36 out.ts -@end example - -@item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream}) -Set bitstream filters for matching streams. @var{bistream_filters} is -a comma-separated list of bitstream filters. Use the @code{-bsfs} option -to get the list of bitstream filters. -@example -avconv -i h264.mp4 -c:v copy -vbsf h264_mp4toannexb -an out.h264 -@end example -@example -avconv -i file.mov -an -vn -sbsf mov2textsub -c:s copy -f rawvideo sub.txt -@end example - -@item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{output,per-stream}) -Force a tag/fourcc for matching streams. -@end table -@c man end OPTIONS - -@chapter Tips -@c man begin TIPS - -@itemize -@item -For streaming at very low bitrate application, use a low frame rate -and a small GOP size. This is especially true for RealVideo where -the Linux player does not seem to be very fast, so it can miss -frames. An example is: - -@example -avconv -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm -@end example - -@item -The parameter 'q' which is displayed while encoding is the current -quantizer. The value 1 indicates that a very good quality could -be achieved. The value 31 indicates the worst quality. If q=31 appears -too often, it means that the encoder cannot compress enough to meet -your bitrate. You must either increase the bitrate, decrease the -frame rate or decrease the frame size. - -@item -If your computer is not fast enough, you can speed up the -compression at the expense of the compression ratio. You can use -'-me zero' to speed up motion estimation, and '-intra' to disable -motion estimation completely (you have only I-frames, which means it -is about as good as JPEG compression). - -@item -To have very low audio bitrates, reduce the sampling frequency -(down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3). - -@item -To have a constant quality (but a variable bitrate), use the option -'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst -quality). - -@end itemize -@c man end TIPS - -@chapter Examples -@c man begin EXAMPLES - -@section Preset files - -A preset file contains a sequence of @var{option=value} pairs, one for -each line, specifying a sequence of options which can be specified also on -the command line. Lines starting with the hash ('#') character are ignored and -are used to provide comments. Empty lines are also ignored. Check the -@file{presets} directory in the Libav source tree for examples. - -Preset files are specified with the @code{pre} option, this option takes a -preset name as input. Avconv searches for a file named @var{preset_name}.avpreset in -the directories @file{$AVCONV_DATADIR} (if set), and @file{$HOME/.avconv}, and in -the data directory defined at configuration time (usually @file{$PREFIX/share/avconv}) -in that order. For example, if the argument is @code{libx264-max}, it will -search for the file @file{libx264-max.avpreset}. - -@section Video and Audio grabbing - -If you specify the input format and device then avconv can grab video -and audio directly. - -@example -avconv -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg -@end example - -Note that you must activate the right video source and channel before -launching avconv with any TV viewer such as -@uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also -have to set the audio recording levels correctly with a -standard mixer. - -@section X11 grabbing - -Grab the X11 display with avconv via - -@example -avconv -f x11grab -s cif -r 25 -i :0.0 /tmp/out.mpg -@end example - -0.0 is display.screen number of your X11 server, same as -the DISPLAY environment variable. - -@example -avconv -f x11grab -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg -@end example - -0.0 is display.screen number of your X11 server, same as the DISPLAY environment -variable. 10 is the x-offset and 20 the y-offset for the grabbing. - -@section Video and Audio file format conversion - -Any supported file format and protocol can serve as input to avconv: - -Examples: -@itemize -@item -You can use YUV files as input: - -@example -avconv -i /tmp/test%d.Y /tmp/out.mpg -@end example - -It will use the files: -@example -/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V, -/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc... -@end example - -The Y files use twice the resolution of the U and V files. They are -raw files, without header. They can be generated by all decent video -decoders. You must specify the size of the image with the @option{-s} option -if avconv cannot guess it. - -@item -You can input from a raw YUV420P file: - -@example -avconv -i /tmp/test.yuv /tmp/out.avi -@end example - -test.yuv is a file containing raw YUV planar data. Each frame is composed -of the Y plane followed by the U and V planes at half vertical and -horizontal resolution. - -@item -You can output to a raw YUV420P file: - -@example -avconv -i mydivx.avi hugefile.yuv -@end example - -@item -You can set several input files and output files: - -@example -avconv -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg -@end example - -Converts the audio file a.wav and the raw YUV video file a.yuv -to MPEG file a.mpg. - -@item -You can also do audio and video conversions at the same time: - -@example -avconv -i /tmp/a.wav -ar 22050 /tmp/a.mp2 -@end example - -Converts a.wav to MPEG audio at 22050 Hz sample rate. - -@item -You can encode to several formats at the same time and define a -mapping from input stream to output streams: - -@example -avconv -i /tmp/a.wav -map 0:a -b 64k /tmp/a.mp2 -map 0:a -b 128k /tmp/b.mp2 -@end example - -Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map -file:index' specifies which input stream is used for each output -stream, in the order of the definition of output streams. - -@item -You can transcode decrypted VOBs: - -@example -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 -@end example - -This is a typical DVD ripping example; the input is a VOB file, the -output an AVI file with MPEG-4 video and MP3 audio. Note that in this -command we use B-frames so the MPEG-4 stream is DivX5 compatible, and -GOP size is 300 which means one intra frame every 10 seconds for 29.97fps -input video. Furthermore, the audio stream is MP3-encoded so you need -to enable LAME support by passing @code{--enable-libmp3lame} to configure. -The mapping is particularly useful for DVD transcoding -to get the desired audio language. - -NOTE: To see the supported input formats, use @code{avconv -formats}. - -@item -You can extract images from a video, or create a video from many images: - -For extracting images from a video: -@example -avconv -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg -@end example - -This will extract one video frame per second from the video and will -output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg}, -etc. Images will be rescaled to fit the new WxH values. - -If you want to extract just a limited number of frames, you can use the -above command in combination with the -vframes or -t option, or in -combination with -ss to start extracting from a certain point in time. - -For creating a video from many images: -@example -avconv -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi -@end example - -The syntax @code{foo-%03d.jpeg} specifies to use a decimal number -composed of three digits padded with zeroes to express the sequence -number. It is the same syntax supported by the C printf function, but -only formats accepting a normal integer are suitable. - -@item -You can put many streams of the same type in the output: - -@example -avconv -i test1.avi -i test2.avi -map 0.3 -map 0.2 -map 0.1 -map 0.0 -c copy test12.nut -@end example - -The resulting output file @file{test12.avi} will contain first four streams from -the input file in reverse order. - -@end itemize -@c man end EXAMPLES - -@include eval.texi -@include encoders.texi -@include demuxers.texi -@include muxers.texi -@include indevs.texi -@include outdevs.texi -@include protocols.texi -@include bitstream_filters.texi -@include filters.texi -@include metadata.texi - -@ignore - -@setfilename avconv -@settitle avconv video converter - -@c man begin SEEALSO -ffplay(1), ffprobe(1), ffserver(1) and the FFmpeg HTML documentation - -@c man end - -@c man begin AUTHORS -The Libav developers -@c man end - -@end ignore - -@bye |