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diff --git a/doc/avconv.texi b/doc/avconv.texi deleted file mode 100644 index 0650051c38..0000000000 --- a/doc/avconv.texi +++ /dev/null @@ -1,1287 +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 Detailed description -@c man begin DETAILED DESCRIPTION - -The transcoding process in @command{avconv} for each output can be described by -the following diagram: - -@example - _______ ______________ -| | | | -| input | demuxer | encoded data | decoder -| file | ---------> | packets | -----+ -|_______| |______________| | - v - _________ - | | - | decoded | - | frames | - |_________| - ________ ______________ | -| | | | | -| output | <-------- | encoded data | <----+ -| file | muxer | packets | encoder -|________| |______________| - - -@end example - -@command{avconv} calls the libavformat library (containing demuxers) to read -input files and get packets containing encoded data from them. When there are -multiple input files, @command{avconv} tries to keep them synchronized by -tracking lowest timestamp on any active input stream. - -Encoded packets are then passed to the decoder (unless streamcopy is selected -for the stream, see further for a description). The decoder produces -uncompressed frames (raw video/PCM audio/...) which can be processed further by -filtering (see next section). After filtering the frames are passed to the -encoder, which encodes them and outputs encoded packets again. Finally those are -passed to the muxer, which writes the encoded packets to the output file. - -@section Filtering -Before encoding, @command{avconv} can process raw audio and video frames using -filters from the libavfilter library. Several chained filters form a filter -graph. @command{avconv} distinguishes between two types of filtergraphs - -simple and complex. - -@subsection Simple filtergraphs -Simple filtergraphs are those that have exactly one input and output, both of -the same type. In the above diagram they can be represented by simply inserting -an additional step between decoding and encoding: - -@example - _________ ______________ -| | | | -| decoded | | encoded data | -| frames |\ /| packets | -|_________| \ / |______________| - \ __________ / - simple \ | | / encoder - filtergraph \| filtered |/ - | frames | - |__________| - -@end example - -Simple filtergraphs are configured with the per-stream @option{-filter} option -(with @option{-vf} and @option{-af} aliases for video and audio respectively). -A simple filtergraph for video can look for example like this: - -@example - _______ _____________ _______ ________ -| | | | | | | | -| input | ---> | deinterlace | ---> | scale | ---> | output | -|_______| |_____________| |_______| |________| - -@end example - -Note that some filters change frame properties but not frame contents. E.g. the -@code{fps} filter in the example above changes number of frames, but does not -touch the frame contents. Another example is the @code{setpts} filter, which -only sets timestamps and otherwise passes the frames unchanged. - -@subsection Complex filtergraphs -Complex filtergraphs are those which cannot be described as simply a linear -processing chain applied to one stream. This is the case e.g. when the graph has -more than one input and/or output, or when output stream type is different from -input. They can be represented with the following diagram: - -@example - _________ -| | -| input 0 |\ __________ -|_________| \ | | - \ _________ /| output 0 | - \ | | / |__________| - _________ \| complex | / -| | | |/ -| input 1 |---->| filter |\ -|_________| | | \ __________ - /| graph | \ | | - / | | \| output 1 | - _________ / |_________| |__________| -| | / -| input 2 |/ -|_________| - -@end example - -Complex filtergraphs are configured with the @option{-filter_complex} option. -Note that this option is global, since a complex filtergraph by its nature -cannot be unambiguously associated with a single stream or file. - -A trivial example of a complex filtergraph is the @code{overlay} filter, which -has two video inputs and one video output, containing one video overlaid on top -of the other. Its audio counterpart is the @code{amix} filter. - -@section Stream copy -Stream copy is a mode selected by supplying the @code{copy} parameter to the -@option{-codec} option. It makes @command{avconv} omit the decoding and encoding -step for the specified stream, so it does only demuxing and muxing. It is useful -for changing the container format or modifying container-level metadata. The -diagram above will in this case simplify to this: - -@example - _______ ______________ ________ -| | | | | | -| input | demuxer | encoded data | muxer | output | -| file | ---------> | packets | -------> | file | -|_______| |______________| |________| - -@end example - -Since there is no decoding or encoding, it is very fast and there is no quality -loss. However it might not work in some cases because of many factors. Applying -filters is obviously also impossible, since filters work on uncompressed data. - -@c man end DETAILED 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}) -Immediately exit when output files already exist. - -@item -loop @var{number} (@emph{input}) -Set number of times input stream shall be looped. Loop 0 means no loop, -loop -1 means infinite loop. - -@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}. Note the in most formats it is not possible to seek exactly, so -@command{avconv} will seek to the closest seek point before @var{position}. -When transcoding and @option{-accurate_seek} is enabled (the default), this -extra segment between the seek point and @var{position} will be decoded and -discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it -will be preserved. - -When used as an output option (before an output filename), decodes but discards -input until the timestamps reach @var{position}. - -@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 obsolete alias for -@code{-frames:d}, which you should use instead. - -@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 -b[:@var{stream_specifier}] @var{bitrate} (@emph{output,per-stream}) -Set the stream bitrate in bits per second. When transcoding, this tells the -encoder to use the specified bitrate for the encoded stream. - -For streamcopy, this provides a hint to the muxer about the bitrate of the input -stream. - -@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). - -See also the @option{-filter_complex} option if you want to create filter graphs -with multiple inputs and/or outputs. - -@item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream}) -This option is similar to @option{-filter}, the only difference is that its -argument is the name of the file from which a filtergraph description is to be -read. - -@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. - -@item -noautorotate -Disable automatically rotating video based on file metadata. - -@end table - -@section Video Options - -@table @option -@item -vframes @var{number} (@emph{output}) -Set the number of video frames to record. This is an obsolete alias for -@code{-frames:v}, which you should use instead. -@item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream}) -Set frame rate (Hz value, fraction or abbreviation). - -As an input option, ignore any timestamps stored in the file and instead -generate timestamps assuming constant frame rate @var{fps}. - -As an output option, duplicate or drop input frames to achieve constant output -frame rate @var{fps} (note that this actually causes the @code{fps} filter to be -inserted to the end of the corresponding filtergraph). - -@item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream}) -Set frame size. - -As an input option, this is a shortcut for the @option{video_size} private -option, recognized by some demuxers for which the frame size is either not -stored in the file or is configurable -- e.g. raw video or video grabbers. - -As an output option, this inserts the @code{scale} video filter to the -@emph{end} of the corresponding filtergraph. Please use the @code{scale} filter -directly to insert it at the beginning or some other place. - -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 -@item 2kdci -2048x1080 -@item 4kdci -4096x2160 -@item uhd2160 -3840x2160 -@item uhd4320 -7680x4320 -@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 -vcodec @var{codec} (@emph{output}) -Set the video codec. This is an alias for @code{-codec:v}. - -@item -pass[:@var{stream_specifier}] @var{n} (@emph{output,per-stream}) -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{stream_specifier}] @var{prefix} (@emph{output,per-stream}) -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 -vdt @var{n} -Discard threshold. - -@item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream}) -rate control override for specific intervals - -@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. - -@item -init_hw_device @var{type}[=@var{name}][:@var{device}[,@var{key=value}...]] -Initialise a new hardware device of type @var{type} called @var{name}, using the -given device parameters. -If no name is specified it will receive a default name of the form "@var{type}%d". - -The meaning of @var{device} and the following arguments depends on the -device type: -@table @option - -@item cuda -@var{device} is the number of the CUDA device. - -@item dxva2 -@var{device} is the number of the Direct3D 9 display adapter. - -@item vaapi -@var{device} is either an X11 display name or a DRM render node. -If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY}) -and then the first DRM render node (@emph{/dev/dri/renderD128}). - -@item vdpau -@var{device} is an X11 display name. -If not specified, it will attempt to open the default X11 display (@emph{$DISPLAY}). - -@item qsv -@var{device} selects a value in @samp{MFX_IMPL_*}. Allowed values are: -@table @option -@item auto -@item sw -@item hw -@item auto_any -@item hw_any -@item hw2 -@item hw3 -@item hw4 -@end table -If not specified, @samp{auto_any} is used. -(Note that it may be easier to achieve the desired result for QSV by creating the -platform-appropriate subdevice (@samp{dxva2} or @samp{vaapi}) and then deriving a -QSV device from that.) - -@end table - -@item -init_hw_device @var{type}[=@var{name}]@@@var{source} -Initialise a new hardware device of type @var{type} called @var{name}, -deriving it from the existing device with the name @var{source}. - -@item -init_hw_device list -List all hardware device types supported in this build of avconv. - -@item -filter_hw_device @var{name} -Pass the hardware device called @var{name} to all filters in any filter graph. -This can be used to set the device to upload to with the @code{hwupload} filter, -or the device to map to with the @code{hwmap} filter. Other filters may also -make use of this parameter when they require a hardware device. Note that this -is typically only required when the input is not already in hardware frames - -when it is, filters will derive the device they require from the context of the -frames they receive as input. - -This is a global setting, so all filters will receive the same device. - -Do not use this option in scripts that should remain functional in future -avconv versions. - -@item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream}) -Use hardware acceleration to decode the matching stream(s). The allowed values -of @var{hwaccel} are: -@table @option -@item none -Do not use any hardware acceleration (the default). - -@item auto -Automatically select the hardware acceleration method. - -@item vda -Use Apple VDA hardware acceleration. - -@item vdpau -Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration. - -@item dxva2 -Use DXVA2 (DirectX Video Acceleration) hardware acceleration. - -@item vaapi -Use VAAPI (Video Acceleration API) hardware acceleration. - -@item qsv -Use the Intel QuickSync Video acceleration for video transcoding. - -Unlike most other values, this option does not enable accelerated decoding (that -is used automatically whenever a qsv decoder is selected), but accelerated -transcoding, without copying the frames into the system memory. - -For it to work, both the decoder and the encoder must support QSV acceleration -and no filters must be used. -@end table - -This option has no effect if the selected hwaccel is not available or not -supported by the chosen decoder. - -Note that most acceleration methods are intended for playback and will not be -faster than software decoding on modern CPUs. Additionally, @command{avconv} -will usually need to copy the decoded frames from the GPU memory into the system -memory, resulting in further performance loss. This option is thus mainly -useful for testing. - -@item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream}) -Select a device to use for hardware acceleration. - -This option only makes sense when the @option{-hwaccel} option is also specified. -It can either refer to an existing device created with @option{-init_hw_device} -by name, or it can create a new device as if -@samp{-init_hw_device} @var{type}:@var{hwaccel_device} -were called immediately before. - -@item -hwaccels -List all hardware acceleration methods supported in this build of avconv. - -@end table - -@section Audio Options - -@table @option -@item -aframes @var{number} (@emph{output}) -Set the number of audio frames to record. This is an obsolete alias for -@code{-frames:a}, which you should use instead. -@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. -@item -af @var{filter_graph} (@emph{output}) -@var{filter_graph} is a description of the filter graph to apply to -the input audio. -Use the option "-filters" to show all the available filters (including -also sources and sinks). This is an alias for @code{-filter:a}. -@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}. -@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 Advanced options - -@table @option -@item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@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. - -An alternative @var{[linklabel]} form will map outputs from complex filter -graphs (see the @option{-filter_complex} option) to the output file. -@var{linklabel} must correspond to a defined output link label in the graph. - -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 - -To pick the English audio stream: -@example -avconv -i INPUT -map 0:m:language:eng 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 -re (@emph{input}) -Read input at native frame rate. Mainly used to simulate a grab device -or live input stream (e.g. when reading from a file). Should not be used -with actual grab devices or live input streams (where it can cause packet -loss). -@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. -This option has been deprecated. Use the @code{asyncts} audio filter instead. -@item -copyts -Copy timestamps from input to output. -@item -copytb -Copy input stream time base from input to output when stream copying. -@item -shortest (@emph{output}) -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{bitstream_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 -bsf:v h264_mp4toannexb -an out.h264 -@end example -@example -avconv -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt -@end example - -@item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{input/output,per-stream}) -Force a tag/fourcc for matching streams. - -@item -filter_complex @var{filtergraph} (@emph{global}) -Define a complex filter graph, i.e. one with arbitrary number of inputs and/or -outputs. For simple graphs -- those with one input and one output of the same -type -- see the @option{-filter} options. @var{filtergraph} is a description of -the filter graph, as described in @ref{Filtergraph syntax}. - -Input link labels must refer to input streams using the -@code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map} -uses). If @var{stream_specifier} matches multiple streams, the first one will be -used. An unlabeled input will be connected to the first unused input stream of -the matching type. - -Output link labels are referred to with @option{-map}. Unlabeled outputs are -added to the first output file. - -Note that with this option it is possible to use only lavfi sources without -normal input files. - -For example, to overlay an image over video -@example -avconv -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map -'[out]' out.mkv -@end example -Here @code{[0:v]} refers to the first video stream in the first input file, -which is linked to the first (main) input of the overlay filter. Similarly the -first video stream in the second input is linked to the second (overlay) input -of overlay. - -Assuming there is only one video stream in each input file, we can omit input -labels, so the above is equivalent to -@example -avconv -i video.mkv -i image.png -filter_complex 'overlay[out]' -map -'[out]' out.mkv -@end example - -Furthermore we can omit the output label and the single output from the filter -graph will be added to the output file automatically, so we can simply write -@example -avconv -i video.mkv -i image.png -filter_complex 'overlay' out.mkv -@end example - -To generate 5 seconds of pure red video using lavfi @code{color} source: -@example -avconv -filter_complex 'color=red' -t 5 out.mkv -@end example - -@item -filter_complex_script @var{filename} (@emph{global}) -This option is similar to @option{-filter_complex}, the only difference is that -its argument is the name of the file from which a complex filtergraph -description is to be read. - -@item -accurate_seek (@emph{input}) -This option enables or disables accurate seeking in input files with the -@option{-ss} option. It is enabled by default, so seeking is accurate when -transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful -e.g. when copying some streams and transcoding the others. - -@item -max_muxing_queue_size @var{packets} (@emph{output,per-stream}) -When transcoding audio and/or video streams, avconv will not begin writing into -the output until it has one packet for each such stream. While waiting for that -to happen, packets for other streams are buffered. This option sets the size of -this buffer, in packets, for the matching output stream. - -The default value of this option should be high enough for most uses, so only -touch this option if you are sure that you need it. - -@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 '-g 0' 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 @code{-frames:v} or @code{-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 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut -@end example - -The resulting output file @file{test12.nut} will contain the first four streams -from the input files in reverse order. - -@item -To force CBR video output: -@example -avconv -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v -@end example - -@item -The four options lmin, lmax, mblmin and 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 - -@end itemize -@c man end EXAMPLES - -@include eval.texi -@include decoders.texi -@include encoders.texi -@include demuxers.texi -@include muxers.texi -@include indevs.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 -avplay(1), avprobe(1) and the Libav HTML documentation -@c man end - -@c man begin AUTHORS -The Libav developers -@c man end - -@end ignore - -@bye |