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diff --git a/doc/ffmpeg.texi b/doc/ffmpeg.texi deleted file mode 100644 index 968d4f68b7..0000000000 --- a/doc/ffmpeg.texi +++ /dev/null @@ -1,1091 +0,0 @@ -\input texinfo @c -*- texinfo -*- - -@settitle ffmpeg Documentation -@titlepage -@center @titlefont{ffmpeg Documentation} -@end titlepage - -@top - -@contents - -@chapter Synopsis - -The generic syntax is: - -@example -@c man begin SYNOPSIS -ffmpeg [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}... -@c man end -@end example - -@chapter Description -@c man begin DESCRIPTION - -ffmpeg 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. - -The command line interface is designed to be intuitive, in the sense -that ffmpeg tries to figure out all parameters that can possibly be -derived automatically. You usually only have to specify the target -bitrate you want. - -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. - -@itemize -@item -To set the video bitrate of the output file to 64kbit/s: -@example -ffmpeg -i input.avi -b 64k output.avi -@end example - -@item -To force the frame rate of the output file to 24 fps: -@example -ffmpeg -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 -ffmpeg -r 1 -i input.m2v -r 24 output.avi -@end example -@end itemize - -The format option may be needed for raw input files. - -By default ffmpeg tries to convert as losslessly as possible: It -uses the same audio and video parameters for the outputs as the one -specified for the inputs. - -@c man end DESCRIPTION - -@chapter Options -@c man begin OPTIONS - -@include avtools-common-opts.texi - -@section Main options - -@table @option - -@item -f @var{fmt} -Force format. - -@item -i @var{filename} -input file name - -@item -y -Overwrite output files. - -@item -t @var{duration} -Restrict the transcoded/captured video sequence -to the duration specified in seconds. -@code{hh:mm:ss[.xxx]} syntax is also supported. - -@item -fs @var{limit_size} -Set the file size limit. - -@item -ss @var{position} -Seek to given time position in seconds. -@code{hh:mm:ss[.xxx]} syntax is also supported. - -@item -itsoffset @var{offset} -Set the input time offset in seconds. -@code{[-]hh:mm:ss[.xxx]} syntax is also supported. -This option affects all the input files that follow it. -The offset is added to the timestamps of the input files. -Specifying a positive offset means that the corresponding -streams are delayed by 'offset' seconds. - -@item -timestamp @var{time} -Set the recording timestamp in the container. -The syntax for @var{time} is: -@example -now|([(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH[:MM[:SS[.m...]]])|(HH[MM[SS[.m...]]]))[Z|z]) -@end example -If the value is "now" it takes the current time. -Time is local time unless 'Z' or 'z' is appended, in which case it is -interpreted as UTC. -If the year-month-day part is not specified it takes the current -year-month-day. - -@item -metadata @var{key}=@var{value} -Set a metadata key/value pair. - -For example, for setting the title in the output file: -@example -ffmpeg -i in.avi -metadata title="my title" out.flv -@end example - -@item -v @var{number} -Set the logging verbosity level. - -@item -target @var{type} -Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50", "pal-vcd", -"ntsc-svcd", ... ). All the format options (bitrate, codecs, -buffer sizes) are then set automatically. You can just type: - -@example -ffmpeg -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 -ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg -@end example - -@item -dframes @var{number} -Set the number of data frames to record. - -@item -scodec @var{codec} -Force subtitle codec ('copy' to copy stream). - -@item -newsubtitle -Add a new subtitle stream to the current output stream. - -@item -slang @var{code} -Set the ISO 639 language code (3 letters) of the current subtitle stream. - -@end table - -@section Video Options - -@table @option -@item -vframes @var{number} -Set the number of video frames to record. -@item -r @var{fps} -Set frame rate (Hz value, fraction or abbreviation), (default = 25). -@item -s @var{size} -Set frame size. The format is @samp{wxh} (avserver default = 160x128, ffmpeg 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{aspect} -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 -croptop @var{size} -@item -cropbottom @var{size} -@item -cropleft @var{size} -@item -cropright @var{size} -All the crop options have been removed. Use -vf -crop=width:height:x:y instead. - -@item -padtop @var{size} -@item -padbottom @var{size} -@item -padleft @var{size} -@item -padright @var{size} -@item -padcolor @var{hex_color} -All the pad options have been removed. Use -vf -pad=width:height:x:y:color instead. -@item -vn -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 -ffmpeg -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} -Force video codec to @var{codec}. Use the @code{copy} special value to -tell that the raw codec data must be copied as is. -@item -sameq -Use same quantizer as source (implies VBR). - -@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 -ffmpeg -i foo.mov -vcodec libxvid -pass 1 -an -f rawvideo -y NUL -ffmpeg -i foo.mov -vcodec libxvid -pass 1 -an -f rawvideo -y /dev/null -@end example - -@item -passlogfile @var{prefix} -Set two-pass log file name prefix to @var{prefix}, the default file name -prefix is ``ffmpeg2pass''. The complete file name will be -@file{PREFIX-N.log}, where N is a number specific to the output -stream. - -@item -newvideo -Add a new video stream to the current output stream. - -@item -vlang @var{code} -Set the ISO 639 language code (3 letters) of the current video stream. - -@item -vf @var{filter_graph} -@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). - -@end table - -@section Advanced Video Options - -@table @option -@item -pix_fmt @var{format} -Set pixel format. Use 'list' as parameter to show all the supported -pixel formats. -@item -sws_flags @var{flags} -Set SwScaler flags. -@item -g @var{gop_size} -Set the group of pictures size. -@item -intra -Use only intra frames. -@item -vdt @var{n} -Discard threshold. -@item -qscale @var{q} -Use fixed video quantizer scale (VBR). -@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 -ffmpeg -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{override} -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 -dct_algo @var{algo} -Set DCT algorithm to @var{algo}. Available values are: -@table @samp -@item 0 -FF_DCT_AUTO (default) -@item 1 -FF_DCT_FASTINT -@item 2 -FF_DCT_INT -@item 3 -FF_DCT_MMX -@item 4 -FF_DCT_MLIB -@item 5 -FF_DCT_ALTIVEC -@end table - -@item -idct_algo @var{algo} -Set IDCT algorithm to @var{algo}. Available values are: -@table @samp -@item 0 -FF_IDCT_AUTO (default) -@item 1 -FF_IDCT_INT -@item 2 -FF_IDCT_SIMPLE -@item 3 -FF_IDCT_SIMPLEMMX -@item 4 -FF_IDCT_LIBMPEG2MMX -@item 5 -FF_IDCT_PS2 -@item 6 -FF_IDCT_MLIB -@item 7 -FF_IDCT_ARM -@item 8 -FF_IDCT_ALTIVEC -@item 9 -FF_IDCT_SH4 -@item 10 -FF_IDCT_SIMPLEARM -@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_EXPLODE -@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 ffmpeg). -@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 -4mv -Use four motion vector by macroblock (MPEG-4 only). -@item -part -Use data partitioning (MPEG-4 only). -@item -bug @var{param} -Work around encoder bugs that are not auto-detected. -@item -strict @var{strictness} -How strictly to follow the standards. -@item -aic -Enable Advanced intra coding (h263+). -@item -umv -Enable Unlimited Motion Vector (h263+) - -@item -deinterlace -Deinterlace pictures. -@item -ilme -Force interlacing support in encoder (MPEG-2 and MPEG-4 only). -Use this option if your input file is interlaced and you want -to keep the interlaced format for minimum losses. -The alternative is to deinterlace the input stream with -@option{-deinterlace}, but deinterlacing introduces losses. -@item -psnr -Calculate PSNR of compressed frames. -@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{n} -top=1/bottom=0/auto=-1 field first -@item -dc @var{precision} -Intra_dc_precision. -@item -vtag @var{fourcc/tag} -Force video tag/fourcc. -@item -qphist -Show QP histogram. -@item -vbsf @var{bitstream_filter} -Bitstream filters available are "dump_extra", "remove_extra", "noise", "h264_mp4toannexb", "imxdump", "mjpegadump", "mjpeg2jpeg". -@example -ffmpeg -i h264.mp4 -vcodec copy -vbsf h264_mp4toannexb -an out.h264 -@end example -@item -force_key_frames @var{time}[,@var{time}...] -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. -@end table - -@section Audio Options - -@table @option -@item -aframes @var{number} -Set the number of audio frames to record. -@item -ar @var{freq} -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} -Set the audio quality (codec-specific, VBR). -@item -ac @var{channels} -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 -Disable audio recording. -@item -acodec @var{codec} -Force audio codec to @var{codec}. Use the @code{copy} special value to -specify that the raw codec data must be copied as is. -@item -newaudio -Add a new audio track to the output file. If you want to specify parameters, -do so before @code{-newaudio} (@code{-acodec}, @code{-ab}, etc..). - -Mapping will be done automatically, if the number of output streams is equal to -the number of input streams, else it will pick the first one that matches. You -can override the mapping using @code{-map} as usual. - -Example: -@example -ffmpeg -i file.mpg -vcodec copy -acodec ac3 -ab 384k test.mpg -acodec mp2 -ab 192k -newaudio -@end example -@item -alang @var{code} -Set the ISO 639 language code (3 letters) of the current audio stream. -@end table - -@section Advanced Audio options: - -@table @option -@item -atag @var{fourcc/tag} -Force audio tag/fourcc. -@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 -@item -absf @var{bitstream_filter} -Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp". -@end table - -@section Subtitle options: - -@table @option -@item -scodec @var{codec} -Force subtitle codec ('copy' to copy stream). -@item -newsubtitle -Add a new subtitle stream to the current output stream. -@item -slang @var{code} -Set the ISO 639 language code (3 letters) of the current subtitle stream. -@item -sn -Disable subtitle recording. -@item -sbsf @var{bitstream_filter} -Bitstream filters available are "mov2textsub", "text2movsub". -@example -ffmpeg -i file.mov -an -vn -sbsf mov2textsub -scodec copy -f rawvideo sub.txt -@end example -@end table - -@section Audio/Video grab options - -@table @option -@item -vc @var{channel} -Set video grab channel (DV1394 only). -@item -tvstd @var{standard} -Set television standard (NTSC, PAL (SECAM)). -@item -isync -Synchronize read on input. -@end table - -@section Advanced options - -@table @option -@item -map @var{input_file_id}.@var{input_stream_id}[:@var{sync_file_id}.@var{sync_stream_id}] - -Designate an input stream 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 indexes start at 0. If specified, -@var{sync_file_id}.@var{sync_stream_id} sets which input stream -is used as a presentation sync reference. - -The @code{-map} options must be specified just after the output file. -If any @code{-map} options are used, the number of @code{-map} options -on the command line must match the number of streams in the output -file. 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. - -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 stream to place in an output file. For -example: -@example -ffmpeg -i INPUT out.wav -map 0.1 -@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 -ffmpeg -i a.mov -i b.mov -vcodec copy -acodec copy out.mov -map 0.2 -map 1.6 -@end example - -To add more streams to the output file, you can use the -@code{-newaudio}, @code{-newvideo}, @code{-newsubtitle} options. - -@item -map_meta_data @var{outfile}[,@var{metadata}]:@var{infile}[,@var{metadata}] -Deprecated, use @var{-map_metadata} instead. - -@item -map_metadata @var{outfile}[,@var{metadata}]:@var{infile}[,@var{metadata}] -Set metadata information of @var{outfile} from @var{infile}. Note that those -are file indices (zero-based), not filenames. -Optional @var{metadata} parameters specify, which metadata to copy - (g)lobal -(i.e. metadata that applies to the whole file), per-(s)tream, per-(c)hapter or -per-(p)rogram. All metadata specifiers other than global must be followed by the -stream/chapter/program number. If metadata specifier is omitted, it defaults to -global. - -By default, global metadata is copied from the first input file to all output files, -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 -ffmpeg -i in.ogg -map_metadata 0:0,s0 out.mp3 -@end example -@item -map_chapters @var{outfile}:@var{infile} -Copy chapters from @var{infile} to @var{outfile}. If no chapter mapping is specified, -then chapters are copied from the first input file with at least one chapter to all -output files. Use a negative file index to disable any chapter copying. -@item -debug -Print specific debug info. -@item -benchmark -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 -dump -Dump each input packet. -@item -hex -When dumping packets, also dump the payload. -@item -bitexact -Only use bit exact algorithms (for codec testing). -@item -ps @var{size} -Set RTP payload size in bytes. -@item -re -Read input at native frame rate. Mainly used to simulate a grab device. -@item -loop_input -Loop over the input stream. Currently it works only for image -streams. This option is used for automatic AVserver testing. -This option is deprecated, use -loop. -@item -loop_output @var{number_of_times} -Repeatedly loop output for formats that support looping such as animated GIF -(0 will loop the output infinitely). -This option is deprecated, use -loop. -@item -threads @var{count} -Thread count. -@item -vsync @var{parameter} -Video sync method. - -@table @option -@item 0 -Each frame is passed with its timestamp from the demuxer to the muxer. -@item 1 -Frames will be duplicated and dropped to achieve exactly the requested -constant framerate. -@item 2 -Frames are passed through with their timestamp or dropped so as to -prevent 2 frames from having the same timestamp. -@item -1 -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} -Set the maximum demux-decode delay. -@item -muxpreload @var{seconds} -Set the initial demux-decode delay. -@item -streamid @var{output-stream-index}:@var{new-value} -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 -ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts -@end example -@end table - -@section Preset files - -A preset file contains a sequence of @var{option}=@var{value} pairs, -one for each line, specifying a sequence of options which would be -awkward to specify on the command line. Lines starting with the hash -('#') character are ignored and are used to provide comments. Check -the @file{presets} directory in the Libav source tree for examples. - -Preset files are specified with the @code{vpre}, @code{apre}, -@code{spre}, and @code{fpre} options. The @code{fpre} option takes the -filename of the preset instead of a preset name as input and can be -used for any kind of codec. For the @code{vpre}, @code{apre}, and -@code{spre} options, the options specified in a preset file are -applied to the currently selected codec of the same type as the preset -option. - -The argument passed to the @code{vpre}, @code{apre}, and @code{spre} -preset options identifies the preset file to use according to the -following rules: - -First ffmpeg searches for a file named @var{arg}.ffpreset in the -directories @file{$AVCONV_DATADIR} (if set), and @file{$HOME/.avconv}, and in -the datadir 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.ffpreset}. - -If no such file is found, then ffmpeg will search for a file named -@var{codec_name}-@var{arg}.ffpreset in the above-mentioned -directories, where @var{codec_name} is the name of the codec to which -the preset file options will be applied. For example, if you select -the video codec with @code{-vcodec libx264} and use @code{-vpre max}, -then it will search for the file @file{libx264-max.ffpreset}. -@c man end - -@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 -ffmpeg -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). - -@item -When converting video files, you can use the '-sameq' option which -uses the same quality factor in the encoder as in the decoder. -It allows almost lossless encoding. - -@end itemize -@c man end TIPS - -@chapter Examples -@c man begin EXAMPLES - -@section Video and Audio grabbing - -If you specify the input format and device then ffmpeg can grab video -and audio directly. - -@example -ffmpeg -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 ffmpeg 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 ffmpeg via - -@example -ffmpeg -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 -ffmpeg -f x11grab -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg -@end example - -10 is the x-offset and 20 the y-offset for the grabbing. - -@example -ffmpeg -f x11grab -follow_mouse centered -s cif -r 25 -i :0.0 /tmp/out.mpg -@end example - -The grabbing region follows the mouse pointer, which stays at the center of -region. - -@example -ffmpeg -f x11grab -follow_mouse 100 -s cif -r 25 -i :0.0 /tmp/out.mpg -@end example - -Only follows when mouse pointer reaches within 100 pixels to the edge of -region. - -@example -ffmpeg -f x11grab -show_region 1 -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg -@end example - -The grabbing region will be indicated on screen. - -@example -ffmpeg -f x11grab -follow_mouse centered -show_region 1 -s cif -r 25 -i :0.0 /tmp/out.mpg -@end example - -The grabbing region indication will follow the mouse pointer. - - -@section Video and Audio file format conversion - -Any supported file format and protocol can serve as input to ffmpeg: - -Examples: -@itemize -@item -You can use YUV files as input: - -@example -ffmpeg -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 ffmpeg cannot guess it. - -@item -You can input from a raw YUV420P file: - -@example -ffmpeg -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 -ffmpeg -i mydivx.avi hugefile.yuv -@end example - -@item -You can set several input files and output files: - -@example -ffmpeg -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 -ffmpeg -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 -ffmpeg -i /tmp/a.wav -ab 64k /tmp/a.mp2 -ab 128k /tmp/b.mp2 -map 0:0 -map 0:0 -@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 -ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800k -g 300 -bf 2 -acodec libmp3lame -ab 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{ffmpeg -formats}. - -@item -You can extract images from a video, or create a video from many images: - -For extracting images from a video: -@example -ffmpeg -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 -ffmpeg -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 -ffmpeg -i test1.avi -i test2.avi -vcodec copy -acodec copy -vcodec copy -acodec copy test12.avi -newvideo -newaudio -@end example - -In addition to the first video and audio streams, the resulting -output file @file{test12.avi} will contain the second video -and the second audio stream found in the input streams list. - -The @code{-newvideo}, @code{-newaudio} and @code{-newsubtitle} -options have to be specified immediately after the name of the output -file to which you want to add them. - -@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 ffmpeg -@settitle ffmpeg video converter - -@c man begin SEEALSO -avplay(1), avprobe(1), avserver(1) and the Libav HTML documentation -@c man end - -@c man begin AUTHORS -The Libav developers -@c man end - -@end ignore - -@bye |