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diff --git a/contrib/ffmpeg/doc/ffmpeg-doc.texi b/contrib/ffmpeg/doc/ffmpeg-doc.texi deleted file mode 100644 index e4e6430fd..000000000 --- a/contrib/ffmpeg/doc/ffmpeg-doc.texi +++ /dev/null @@ -1,1656 +0,0 @@ -\input texinfo @c -*- texinfo -*- - -@settitle FFmpeg Documentation -@titlepage -@sp 7 -@center @titlefont{FFmpeg Documentation} -@sp 3 -@end titlepage - - -@chapter Introduction - -FFmpeg is a very fast video and audio converter. It can also grab from -a live audio/video source. - -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. - -FFmpeg can also convert from any sample rate to any other, and resize -video on the fly with a high quality polyphase filter. - -@chapter Quick Start - -@c man begin EXAMPLES -@section Video and Audio grabbing - -FFmpeg can grab video and audio from devices given that you specify the input -format and device. - -@example -ffmpeg -f audio_device -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 xawtv -(@url{http://bytesex.org/xawtv/}) by Gerd Knorr. You also -have to set the audio recording levels correctly with a -standard mixer. - -@section X11 grabbing - -FFmpeg can grab the X11 display. - -@example -ffmpeg -f x11grab -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 -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 - -* FFmpeg can use any supported file format and protocol as input: - -Examples: - -* 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. - -* 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. - -* You can output to a raw YUV420P file: - -@example -ffmpeg -i mydivx.avi hugefile.yuv -@end example - -* 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. - -* 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 22050Hz sample rate. - -* 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. - -* You can transcode decrypted VOBs - -@example -ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800k -g 300 -bf 2 -acodec mp3 -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-mp3lame} 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}. -@c man end - -@chapter Invocation - -@section Syntax - -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 -@c man begin DESCRIPTION -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. - -* To set the video bitrate of the output file to 64kbit/s: -@example -ffmpeg -i input.avi -b 64k output.avi -@end example - -* To force the frame rate of the input and output file to 24 fps: -@example -ffmpeg -r 24 -i input.avi output.avi -@end example - -* To force the frame rate of the output file to 24 fps: -@example -ffmpeg -i input.avi -r 24 output.avi -@end example - -* To force the frame rate of input file to 1 fps and the output file to 24 fps: -@example -ffmpeg -r 1 -i input.avi -r 24 output.avi -@end example - -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 - -@c man begin OPTIONS -@section Main options - -@table @option -@item -L -Show license. - -@item -h -Show help. - -@item -version -Show version. - -@item -formats -Show available formats, codecs, protocols, ... - -@item -f fmt -Force format. - -@item -i filename -input filename - -@item -y -Overwrite output files. - -@item -t duration -Set the recording time in seconds. -@code{hh:mm:ss[.xxx]} syntax is also supported. - -@item -fs limit_size -Set the file size limit. - -@item -ss position -Seek to given time position in seconds. -@code{hh:mm:ss[.xxx]} syntax is also supported. - -@item -itsoffset 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 -title string -Set the title. - -@item -timestamp time -Set the timestamp. - -@item -author string -Set the author. - -@item -copyright string -Set the copyright. - -@item -comment string -Set the comment. - -@item -album string -Set the album. - -@item -track number -Set the track. - -@item -year number -Set the year. - -@item -v verbose -Control amount of logging. - -@item -target 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 number -Set the number of data frames to record. - -@item -scodec codec -Force subtitle codec ('copy' to copy stream). - -@item -newsubtitle -Add a new subtitle stream to the current output stream. - -@item -slang code -Set the ISO 639 language code (3 letters) of the current subtitle stream. - -@end table - -@section Video Options - -@table @option -@item -b bitrate -Set the video bitrate in bit/s (default = 200 kb/s). -@item -vframes number -Set the number of video frames to record. -@item -r fps -Set frame rate (Hz value, fraction or abbreviation), (default = 25). -@item -s size -Set frame size. The format is @samp{wxh} (ffserver 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 -@end table - -@item -aspect aspect -Set aspect ratio (4:3, 16:9 or 1.3333, 1.7777). -@item -croptop size -Set top crop band size (in pixels). -@item -cropbottom size -Set bottom crop band size (in pixels). -@item -cropleft size -Set left crop band size (in pixels). -@item -cropright size -Set right crop band size (in pixels). -@item -padtop size -Set top pad band size (in pixels). -@item -padbottom size -Set bottom pad band size (in pixels). -@item -padleft size -Set left pad band size (in pixels). -@item -padright size -Set right pad band size (in pixels). -@item -padcolor (hex color) -Set color of padded bands. The value for padcolor is expressed -as a six digit hexadecimal number where the first two digits -represent red, the middle two digits green and last two digits -blue (default = 000000 (black)). -@item -vn -Disable video recording. -@item -bt tolerance -Set video bitrate tolerance (in bit/s). -@item -maxrate bitrate -Set max video bitrate tolerance (in bit/s). -@item -minrate bitrate -Set min video bitrate tolerance (in bit/s). -@item -bufsize size -Set rate control buffer size (in bits). -@item -vcodec 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 video quality as source (implies VBR). - -@item -pass n -Select the pass number (1 or 2). It is useful to do two pass -encoding. The statistics of the video are recorded in the first -pass and the video is generated at the exact requested bitrate -in the second pass. - -@item -passlogfile file -Set two pass logfile name to @var{file}. - -@item -newvideo -Add a new video stream to the current output stream. - -@end table - -@section Advanced Video Options - -@table @option -@item -pix_fmt format -Set pixel format. -@item -g gop_size -Set the group of pictures size. -@item -intra -Use only intra frames. -@item -vdt n -Discard threshold. -@item -qscale q -Use fixed video quantizer scale (VBR). -@item -qmin q -minimum video quantizer scale (VBR) -@item -qmax q -maximum video quantizer scale (VBR) -@item -qdiff q -maximum difference between the quantizer scales (VBR) -@item -qblur blur -video quantizer scale blur (VBR) -@item -qcomp compression -video quantizer scale compression (VBR) - -@item -lmin lambda -minimum video lagrange factor (VBR) -@item -lmax lambda -max video lagrange factor (VBR) -@item -mblmin lambda -minimum macroblock quantizer scale (VBR) -@item -mblmax 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 complexity -initial complexity for single pass encoding -@item -b_qfactor factor -qp factor between P- and B-frames -@item -i_qfactor factor -qp factor between P- and I-frames -@item -b_qoffset offset -qp offset between P- and B-frames -@item -i_qoffset offset -qp offset between P- and I-frames -@item -rc_eq equation -Set rate control equation (@pxref{FFmpeg formula -evaluator}) (default = @code{tex^qComp}). -@item -rc_override override -rate control override for specific intervals -@item -me 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 epzs -(default method) -@item full -exhaustive search (slow and marginally better than epzs) -@end table - -@item -dct_algo 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 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 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 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 frames -Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4). -@item -mbd 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 param -Work around encoder bugs that are not auto-detected. -@item -strict 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 -vhook module -Insert video processing @var{module}. @var{module} contains the module -name and its parameters separated by spaces. -@item -top n -top=1/bottom=0/auto=-1 field first -@item -dc precision -Intra_dc_precision. -@item -vtag fourcc/tag -Force video tag/fourcc. -@item -qphist -Show QP histogram. -@item -vbsf bitstream filter -Bitstream filters available are "dump_extra", "remove_extra", "noise". -@end table - -@section Audio Options - -@table @option -@item -aframes number -Set the number of audio frames to record. -@item -ar freq -Set the audio sampling frequency (default = 44100 Hz). -@item -ab bitrate -Set the audio bitrate in bit/s (default = 64k). -@item -ac channels -Set the number of audio channels (default = 1). -@item -an -Disable audio recording. -@item -acodec 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 code -Set the ISO 639 language code (3 letters) of the current audio stream. -@end table - -@section Advanced Audio options: - -@table @option -@item -atag fourcc/tag -Force audio tag/fourcc. -@item -absf bitstream filter -Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp". -@end table - -@section Subtitle options: - -@table @option -@item -scodec codec -Force subtitle codec ('copy' to copy stream). -@item -newsubtitle -Add a new subtitle stream to the current output stream. -@item -slang code -Set the ISO 639 language code (3 letters) of the current subtitle stream. -@end table - -@section Audio/Video grab options - -@table @option -@item -vc channel -Set video grab channel (DV1394 only). -@item -tvstd standard -Set television standard (NTSC, PAL (SECAM)). -@item -isync -Synchronize read on input. -@end table - -@section Advanced options - -@table @option -@item -map input stream id[:input stream id] -Set stream mapping from input streams to output streams. -Just enumerate the input streams in the order you want them in the output. -[input stream id] sets the (input) stream to sync against. -@item -map_meta_data outfile:infile -Set meta data information of outfile from infile. -@item -debug -Print specific debug info. -@item -benchmark -Add timings for benchmarking. -@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 size -Set packet size in bits. -@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 FFserver testing. -@item -loop_output number_of_times -Repeatedly loop output for formats that support looping such as animated GIF -(0 will loop the output infinitely). -@item -threads count -Thread count. -@item -vsync parameter -Video sync method. Video will be stretched/squeezed to match the timestamps, -it is done by duplicating and dropping frames. 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 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. -@end table - -@node FFmpeg formula evaluator -@section FFmpeg formula evaluator - -When evaluating a rate control string, FFmpeg uses an internal formula -evaluator. - -The following binary operators are available: @code{+}, @code{-}, -@code{*}, @code{/}, @code{^}. - -The following unary operators are available: @code{+}, @code{-}, -@code{(...)}. - -The following functions are available: -@table @var -@item sinh(x) -@item cosh(x) -@item tanh(x) -@item sin(x) -@item cos(x) -@item tan(x) -@item exp(x) -@item log(x) -@item squish(x) -@item gauss(x) -@item abs(x) -@item max(x, y) -@item min(x, y) -@item gt(x, y) -@item lt(x, y) -@item eq(x, y) -@item bits2qp(bits) -@item qp2bits(qp) -@end table - -The following constants are available: -@table @var -@item PI -@item E -@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 - -@c man end - -@ignore - -@setfilename ffmpeg -@settitle FFmpeg video converter - -@c man begin SEEALSO -ffserver(1), ffplay(1) and the HTML documentation of @file{ffmpeg}. -@c man end - -@c man begin AUTHOR -Fabrice Bellard -@c man end - -@end ignore - -@section Protocols - -The filename can be @file{-} to read from standard input or to write -to standard output. - -FFmpeg also handles many protocols specified with an URL syntax. - -Use 'ffmpeg -formats' to see a list of the supported protocols. - -The protocol @code{http:} is currently used only to communicate with -FFserver (see the FFserver documentation). When FFmpeg will be a -video player it will also be used for streaming :-) - -@chapter 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 kHz for MPEG audio, 22050 or 11025 for AC3). - -@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 - - -@chapter external libraries - -FFmpeg can be hooked up with a number of external libraries to add support -for more formats. - -@section AMR - -AMR comes in two different flavors, WB and NB. FFmpeg can make use of the -AMR WB (floating-point mode) and the AMR NB (both floating-point and -fixed-point mode) reference decoders and encoders. - -@itemize - -@item For AMR WB floating-point download TS26.204 V5.1.0 from -@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.204/26204-510.zip} -and extract the source to @file{libavcodec/amrwb_float/}. - -@item For AMR NB floating-point download TS26.104 REL-5 V5.1.0 from -@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.104/26104-510.zip} -and extract the source to @file{libavcodec/amr_float/}. -If you try this on Alpha, you may need to change @code{Word32} to -@code{int} in @file{amr/typedef.h}. - -@item For AMR NB fixed-point download TS26.073 REL-5 V5.1.0 from -@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.073/26073-510.zip} -and extract the source to @file{libavcodec/amr}. -You must also add @code{-DMMS_IO} and remove @code{-pedantic-errors} -to/from @code{CFLAGS} in @file{libavcodec/amr/makefile}, i.e. -``@code{CFLAGS = -Wall -I. \$(CFLAGS_\$(MODE)) -D\$(VAD) -DMMS_IO}''. - -@end itemize - - -@chapter Supported File Formats and Codecs - -You can use the @code{-formats} option to have an exhaustive list. - -@section File Formats - -FFmpeg supports the following file formats through the @code{libavformat} -library: - -@multitable @columnfractions .4 .1 .1 .4 -@item Supported File Format @tab Encoding @tab Decoding @tab Comments -@item MPEG audio @tab X @tab X -@item MPEG-1 systems @tab X @tab X -@tab muxed audio and video -@item MPEG-2 PS @tab X @tab X -@tab also known as @code{VOB} file -@item MPEG-2 TS @tab @tab X -@tab also known as DVB Transport Stream -@item ASF@tab X @tab X -@item AVI@tab X @tab X -@item WAV@tab X @tab X -@item Macromedia Flash@tab X @tab X -@tab Only embedded audio is decoded. -@item FLV @tab X @tab X -@tab Macromedia Flash video files -@item Real Audio and Video @tab X @tab X -@item Raw AC3 @tab X @tab X -@item Raw MJPEG @tab X @tab X -@item Raw MPEG video @tab X @tab X -@item Raw PCM8/16 bits, mulaw/Alaw@tab X @tab X -@item Raw CRI ADX audio @tab X @tab X -@item Raw Shorten audio @tab @tab X -@item SUN AU format @tab X @tab X -@item NUT @tab X @tab X @tab NUT Open Container Format -@item QuickTime @tab X @tab X -@item MPEG-4 @tab X @tab X -@tab MPEG-4 is a variant of QuickTime. -@item Raw MPEG4 video @tab X @tab X -@item DV @tab X @tab X -@item 4xm @tab @tab X -@tab 4X Technologies format, used in some games. -@item Playstation STR @tab @tab X -@item Id RoQ @tab @tab X -@tab Used in Quake III, Jedi Knight 2, other computer games. -@item Interplay MVE @tab @tab X -@tab Format used in various Interplay computer games. -@item WC3 Movie @tab @tab X -@tab Multimedia format used in Origin's Wing Commander III computer game. -@item Sega FILM/CPK @tab @tab X -@tab Used in many Sega Saturn console games. -@item Westwood Studios VQA/AUD @tab @tab X -@tab Multimedia formats used in Westwood Studios games. -@item Id Cinematic (.cin) @tab @tab X -@tab Used in Quake II. -@item FLIC format @tab @tab X -@tab .fli/.flc files -@item Sierra VMD @tab @tab X -@tab Used in Sierra CD-ROM games. -@item Sierra Online @tab @tab X -@tab .sol files used in Sierra Online games. -@item Matroska @tab @tab X -@item Electronic Arts Multimedia @tab @tab X -@tab Used in various EA games; files have extensions like WVE and UV2. -@item Nullsoft Video (NSV) format @tab @tab X -@item ADTS AAC audio @tab X @tab X -@item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro. -@item American Laser Games MM @tab @tab X -@tab Multimedia format used in games like Mad Dog McCree -@item AVS @tab @tab X -@tab Multimedia format used by the Creature Shock game. -@item Smacker @tab @tab X -@tab Multimedia format used by many games. -@item GXF @tab X @tab X -@tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers. -@item CIN @tab @tab X -@tab Multimedia format used by Delphine Software games. -@item MXF @tab @tab X -@tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry. -@item SEQ @tab @tab X -@tab Tiertex .seq files used in the DOS CDROM version of the game Flashback. -@item DXA @tab @tab X -@tab This format is used in non-Windows version of Feeble Files game and -different game cutscenes repacked for use with ScummVM. -@item THP @tab @tab X -@tab Used on the Nintendo GameCube (video only) -@end multitable - -@code{X} means that encoding (resp. decoding) is supported. - -@section Image Formats - -FFmpeg can read and write images for each frame of a video sequence. The -following image formats are supported: - -@multitable @columnfractions .4 .1 .1 .4 -@item Supported Image Format @tab Encoding @tab Decoding @tab Comments -@item PGM, PPM @tab X @tab X -@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support. -@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0 -@item JPEG @tab X @tab X @tab Progressive JPEG is not supported. -@item .Y.U.V @tab X @tab X @tab one raw file per component -@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated. -@item PNG @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet. -@item Targa @tab @tab X @tab Targa (.TGA) image format. -@item TIFF @tab @tab X @tab Only 24 bit/pixel images are supported. -@item SGI @tab X @tab X @tab SGI RGB image format -@end multitable - -@code{X} means that encoding (resp. decoding) is supported. - -@section Video Codecs - -@multitable @columnfractions .4 .1 .1 .4 -@item Supported Codec @tab Encoding @tab Decoding @tab Comments -@item MPEG-1 video @tab X @tab X -@item MPEG-2 video @tab X @tab X -@item MPEG-4 @tab X @tab X -@item MSMPEG4 V1 @tab X @tab X -@item MSMPEG4 V2 @tab X @tab X -@item MSMPEG4 V3 @tab X @tab X -@item WMV7 @tab X @tab X -@item WMV8 @tab X @tab X @tab not completely working -@item WMV9 @tab @tab X @tab not completely working -@item VC1 @tab @tab X -@item H.261 @tab X @tab X -@item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0 -@item H.264 @tab @tab X -@item RealVideo 1.0 @tab X @tab X -@item RealVideo 2.0 @tab X @tab X -@item MJPEG @tab X @tab X -@item lossless MJPEG @tab X @tab X -@item JPEG-LS @tab X @tab X @tab fourcc: MJLS, lossless and near-lossless is supported -@item Apple MJPEG-B @tab @tab X -@item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X -@item DV @tab X @tab X -@item HuffYUV @tab X @tab X -@item FFmpeg Video 1 @tab X @tab X @tab experimental lossless codec (fourcc: FFV1) -@item FFmpeg Snow @tab X @tab X @tab experimental wavelet codec (fourcc: SNOW) -@item Asus v1 @tab X @tab X @tab fourcc: ASV1 -@item Asus v2 @tab X @tab X @tab fourcc: ASV2 -@item Creative YUV @tab @tab X @tab fourcc: CYUV -@item Sorenson Video 1 @tab X @tab X @tab fourcc: SVQ1 -@item Sorenson Video 3 @tab @tab X @tab fourcc: SVQ3 -@item On2 VP3 @tab @tab X @tab still experimental -@item On2 VP5 @tab @tab X @tab fourcc: VP50 -@item On2 VP6 @tab @tab X @tab fourcc: VP60,VP61,VP62 -@item Theora @tab X @tab X @tab still experimental -@item Intel Indeo 3 @tab @tab X -@item FLV @tab X @tab X @tab Sorenson H.263 used in Flash -@item Flash Screen Video @tab X @tab X @tab fourcc: FSV1 -@item ATI VCR1 @tab @tab X @tab fourcc: VCR1 -@item ATI VCR2 @tab @tab X @tab fourcc: VCR2 -@item Cirrus Logic AccuPak @tab @tab X @tab fourcc: CLJR -@item 4X Video @tab @tab X @tab Used in certain computer games. -@item Sony Playstation MDEC @tab @tab X -@item Id RoQ @tab @tab X @tab Used in Quake III, Jedi Knight 2, other computer games. -@item Xan/WC3 @tab @tab X @tab Used in Wing Commander III .MVE files. -@item Interplay Video @tab @tab X @tab Used in Interplay .MVE files. -@item Apple Animation @tab @tab X @tab fourcc: 'rle ' -@item Apple Graphics @tab @tab X @tab fourcc: 'smc ' -@item Apple Video @tab @tab X @tab fourcc: rpza -@item Apple QuickDraw @tab @tab X @tab fourcc: qdrw -@item Cinepak @tab @tab X -@item Microsoft RLE @tab @tab X -@item Microsoft Video-1 @tab @tab X -@item Westwood VQA @tab @tab X -@item Id Cinematic Video @tab @tab X @tab Used in Quake II. -@item Planar RGB @tab @tab X @tab fourcc: 8BPS -@item FLIC video @tab @tab X -@item Duck TrueMotion v1 @tab @tab X @tab fourcc: DUCK -@item Duck TrueMotion v2 @tab @tab X @tab fourcc: TM20 -@item VMD Video @tab @tab X @tab Used in Sierra VMD files. -@item MSZH @tab @tab X @tab Part of LCL -@item ZLIB @tab X @tab X @tab Part of LCL, encoder experimental -@item TechSmith Camtasia @tab @tab X @tab fourcc: TSCC -@item IBM Ultimotion @tab @tab X @tab fourcc: ULTI -@item Miro VideoXL @tab @tab X @tab fourcc: VIXL -@item QPEG @tab @tab X @tab fourccs: QPEG, Q1.0, Q1.1 -@item LOCO @tab @tab X @tab -@item Winnov WNV1 @tab @tab X @tab -@item Autodesk Animator Studio Codec @tab @tab X @tab fourcc: AASC -@item Fraps FPS1 @tab @tab X @tab -@item CamStudio @tab @tab X @tab fourcc: CSCD -@item American Laser Games Video @tab @tab X @tab Used in games like Mad Dog McCree -@item ZMBV @tab X @tab X @tab Encoder works only on PAL8 -@item AVS Video @tab @tab X @tab Video encoding used by the Creature Shock game. -@item Smacker Video @tab @tab X @tab Video encoding used in Smacker. -@item RTjpeg @tab @tab X @tab Video encoding used in NuppelVideo files. -@item KMVC @tab @tab X @tab Codec used in Worms games. -@item VMware Video @tab @tab X @tab Codec used in videos captured by VMware. -@item Cin Video @tab @tab X @tab Codec used in Delphine Software games. -@item Tiertex Seq Video @tab @tab X @tab Codec used in DOS CDROM FlashBack game. -@item DXA Video @tab @tab X @tab Codec originally used in Feeble Files game. -@item AVID DNxHD @tab @tab X @tab aka SMPTE VC3 -@end multitable - -@code{X} means that encoding (resp. decoding) is supported. - -@section Audio Codecs - -@multitable @columnfractions .4 .1 .1 .1 .7 -@item Supported Codec @tab Encoding @tab Decoding @tab Comments -@item MPEG audio layer 2 @tab IX @tab IX -@item MPEG audio layer 1/3 @tab IX @tab IX -@tab MP3 encoding is supported through the external library LAME. -@item AC3 @tab IX @tab IX -@tab liba52 is used internally for decoding. -@item Vorbis @tab X @tab X -@item WMA V1/V2 @tab X @tab X -@item AAC @tab X @tab X -@tab Supported through the external library libfaac/libfaad. -@item Microsoft ADPCM @tab X @tab X -@item MS IMA ADPCM @tab X @tab X -@item QT IMA ADPCM @tab @tab X -@item 4X IMA ADPCM @tab @tab X -@item G.726 ADPCM @tab X @tab X -@item Duck DK3 IMA ADPCM @tab @tab X -@tab Used in some Sega Saturn console games. -@item Duck DK4 IMA ADPCM @tab @tab X -@tab Used in some Sega Saturn console games. -@item Westwood Studios IMA ADPCM @tab @tab X -@tab Used in Westwood Studios games like Command and Conquer. -@item SMJPEG IMA ADPCM @tab @tab X -@tab Used in certain Loki game ports. -@item CD-ROM XA ADPCM @tab @tab X -@item CRI ADX ADPCM @tab X @tab X -@tab Used in Sega Dreamcast games. -@item Electronic Arts ADPCM @tab @tab X -@tab Used in various EA titles. -@item Creative ADPCM @tab @tab X -@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2 -@item RA144 @tab @tab X -@tab Real 14400 bit/s codec -@item RA288 @tab @tab X -@tab Real 28800 bit/s codec -@item RADnet @tab X @tab IX -@tab Real low bitrate AC3 codec, liba52 is used for decoding. -@item AMR-NB @tab X @tab X -@tab Supported through an external library. -@item AMR-WB @tab X @tab X -@tab Supported through an external library. -@item DV audio @tab @tab X -@item Id RoQ DPCM @tab @tab X -@tab Used in Quake III, Jedi Knight 2, other computer games. -@item Interplay MVE DPCM @tab @tab X -@tab Used in various Interplay computer games. -@item Xan DPCM @tab @tab X -@tab Used in Origin's Wing Commander IV AVI files. -@item Sierra Online DPCM @tab @tab X -@tab Used in Sierra Online game audio files. -@item Apple MACE 3 @tab @tab X -@item Apple MACE 6 @tab @tab X -@item FLAC lossless audio @tab @tab X -@item Shorten lossless audio @tab @tab X -@item Apple lossless audio @tab @tab X -@tab QuickTime fourcc 'alac' -@item FFmpeg Sonic @tab X @tab X -@tab experimental lossy/lossless codec -@item Qdesign QDM2 @tab @tab X -@tab there are still some distortions -@item Real COOK @tab @tab X -@tab All versions except 5.1 are supported -@item DSP Group TrueSpeech @tab @tab X -@item True Audio (TTA) @tab @tab X -@item Smacker Audio @tab @tab X -@item WavPack Audio @tab @tab X -@item Cin Audio @tab @tab X -@tab Codec used in Delphine Software games. -@item Intel Music Coder @tab @tab X -@item Musepack @tab @tab X -@tab Only SV7 is supported -@item DT$ Coherent Audio @tab @tab X -@end multitable - -@code{X} means that encoding (resp. decoding) is supported. - -@code{I} means that an integer-only version is available, too (ensures high -performance on systems without hardware floating point support). - -@chapter Platform Specific information - -@section BSD - -BSD make will not build FFmpeg, you need to install and use GNU Make -(@file{gmake}). - -@section Windows - -To get help and instructions for using FFmpeg under Windows, check out -the FFmpeg Windows Help Forum at -@url{http://arrozcru.no-ip.org/ffmpeg/}. - -@subsection Native Windows compilation - -@itemize -@item Install the current versions of MSYS and MinGW from -@url{http://www.mingw.org/}. You can find detailed installation -instructions in the download section and the FAQ. - -NOTE: Use at least bash 3.1. Older versions are known to be failing on the -configure script. - -@item If you want to test the FFplay, also download -the MinGW development library of SDL 1.2.x -(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from -@url{http://www.libsdl.org}. Unpack it in a temporary directory, and -unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool -directory. Edit the @file{sdl-config} script so that it gives the -correct SDL directory when invoked. - -@item Extract the current version of FFmpeg. - -@item Start the MSYS shell (file @file{msys.bat}). - -@item Change to the FFmpeg directory and follow - the instructions of how to compile FFmpeg (file -@file{INSTALL}). Usually, launching @file{./configure} and @file{make} -suffices. If you have problems using SDL, verify that -@file{sdl-config} can be launched from the MSYS command line. - -@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing -@file{make install}. Do not forget to copy @file{SDL.dll} to the place -you launch @file{ffplay} from. - -@end itemize - -Notes: -@itemize - -@item The target @file{make wininstaller} can be used to create a -Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll} -must be copied to the FFmpeg directory in order to build the -installer. - -@item By using @code{./configure --enable-shared} when configuring FFmpeg, -you can build @file{avcodec.dll} and @file{avformat.dll}. With -@code{make install} you install the FFmpeg DLLs and the associated -headers in @file{Program Files/FFmpeg}. - -@item Visual C++ compatibility: If you used @code{./configure --enable-shared} -when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual -C++ @code{lib} tool to build @code{avcodec.lib} and -@code{avformat.lib}. With these libraries you can link your Visual C++ -code directly with the FFmpeg DLLs (see below). - -@end itemize - -@subsection Visual C++ compatibility - -FFmpeg will not compile under Visual C++ -- and it has too many -dependencies on the GCC compiler to make a port viable. However, -if you want to use the FFmpeg libraries in your own applications, -you can still compile those applications using Visual C++. An -important restriction to this is that you have to use the -dynamically linked versions of the FFmpeg libraries (i.e. the -DLLs), and you have to make sure that Visual-C++-compatible -import libraries are created during the FFmpeg build process. - -This description of how to use the FFmpeg libraries with Visual C++ is -based on Visual C++ 2005 Express Edition Beta 2. If you have a different -version, you might have to modify the procedures slightly. - -Here are the step-by-step instructions for building the FFmpeg libraries -so they can be used with Visual C++: - -@enumerate - -@item Install Visual C++ (if you have not done so already). - -@item Install MinGW and MSYS as described above. - -@item Add a call to @file{vcvars32.bat} (which sets up the environment -variables for the Visual C++ tools) as the first line of -@file{msys.bat}. The standard location for @file{vcvars32.bat} is -@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat}, -and the standard location for @file{msys.bat} is -@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the -following line as the first line of @file{msys.bat}: - -@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"} - -@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}. -If you get a help message with the command line options of @code{link.exe}, -this means your environment variables are set up correctly, the -Microsoft linker is on the path and will be used by FFmpeg to -create Visual-C++-compatible import libraries. - -@item Extract the current version of FFmpeg and change to the FFmpeg directory. - -@item Type the command -@code{./configure --enable-shared --disable-static --enable-memalign-hack} -to configure and, if that did not produce any errors, -type @code{make} to build FFmpeg. - -@item The subdirectories @file{libavformat}, @file{libavcodec}, and -@file{libavutil} should now contain the files @file{avformat.dll}, -@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib}, -@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three -DLLs to your System32 directory (typically @file{C:\Windows\System32}). - -@end enumerate - -And here is how to use these libraries with Visual C++: - -@enumerate - -@item Create a new console application ("File / New / Project") and then -select "Win32 Console Application". On the appropriate page of the -Application Wizard, uncheck the "Precompiled headers" option. - -@item Write the source code for your application, or, for testing, just -copy the code from an existing sample application into the source file -that Visual C++ has already created for you. (Note that your source -filehas to have a @code{.cpp} extension; otherwise, Visual C++ will not -compile the FFmpeg headers correctly because in C mode, it does not -recognize the @code{inline} keyword.) For example, you can copy -@file{output_example.c} from the FFmpeg distribution (but you will -have to make minor modifications so the code will compile under -C++, see below). - -@item Open the "Project / Properties" dialog box. In the "Configuration" -combo box, select "All Configurations" so that the changes you make will -affect both debug and release builds. In the tree view on the left hand -side, select "C/C++ / General", then edit the "Additional Include -Directories" setting to contain the complete paths to the -@file{libavformat}, @file{libavcodec}, and @file{libavutil} -subdirectories of your FFmpeg directory. Note that the directories have -to be separated using semicolons. Now select "Linker / General" from the -tree view and edit the "Additional Library Directories" setting to -contain the same three directories. - -@item Still in the "Project / Properties" dialog box, select "Linker / Input" -from the tree view, then add the files @file{avformat.lib}, -@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional -Dependencies". Note that the names of the libraries have to be separated -using spaces. - -@item Now, select "C/C++ / Code Generation" from the tree view. Select -"Debug" in the "Configuration" combo box. Make sure that "Runtime -Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in -the "Configuration" combo box and make sure that "Runtime Library" is -set to "Multi-threaded DLL". - -@item Click "OK" to close the "Project / Properties" dialog box and build -the application. Hopefully, it should compile and run cleanly. If you -used @file{output_example.c} as your sample application, you will get a -few compiler errors, but they are easy to fix. The first type of error -occurs because Visual C++ does not allow an @code{int} to be converted to -an @code{enum} without a cast. To solve the problem, insert the required -casts (this error occurs once for a @code{CodecID} and once for a -@code{CodecType}). The second type of error occurs because C++ requires -the return value of @code{malloc} to be cast to the exact type of the -pointer it is being assigned to. Visual C++ will complain that, for -example, @code{(void *)} is being assigned to @code{(uint8_t *)} without -an explicit cast. So insert an explicit cast in these places to silence -the compiler. The third type of error occurs because the @code{snprintf} -library function is called @code{_snprintf} under Visual C++. So just -add an underscore to fix the problem. With these changes, -@file{output_example.c} should compile under Visual C++, and the -resulting executable should produce valid video files. - -@end enumerate - -@subsection Cross compilation for Windows with Linux - -You must use the MinGW cross compilation tools available at -@url{http://www.mingw.org/}. - -Then configure FFmpeg with the following options: -@example -./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc- -@end example -(you can change the cross-prefix according to the prefix chosen for the -MinGW tools). - -Then you can easily test FFmpeg with Wine -(@url{http://www.winehq.com/}). - -@subsection Compilation under Cygwin - -Cygwin works very much like Unix. - -Just install your Cygwin with all the "Base" packages, plus the -following "Devel" ones: -@example -binutils, gcc-core, make, subversion -@end example - -Do not install binutils-20060709-1 (they are buggy on shared builds); -use binutils-20050610-1 instead. - -Then run - -@example -./configure --enable-static --disable-shared -@end example - -to make a static build or - -@example -./configure --enable-shared --disable-static -@end example - -to build shared libraries. - -If you want to build FFmpeg with additional libraries, download Cygwin -"Devel" packages for Ogg and Vorbis from any Cygwin packages repository -and/or SDL, xvid, faac, faad2 packages from Cygwin Ports, -(@url{http://cygwinports.dotsrc.org/}). - -@subsection Crosscompilation for Windows under Cygwin - -With Cygwin you can create Windows binaries that do not need the cygwin1.dll. - -Just install your Cygwin as explained before, plus these additional -"Devel" packages: -@example -gcc-mingw-core, mingw-runtime, mingw-zlib -@end example - -and add some special flags to your configure invocation. - -For a static build run -@example -./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin -@end example - -and for a build with shared libraries -@example -./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin -@end example - -@section BeOS - -The configure script should guess the configuration itself. -Networking support is currently not finished. -errno issues fixed by Andrew Bachmann. - -Old stuff: - -François Revol - revol at free dot fr - April 2002 - -The configure script should guess the configuration itself, -however I still did not test building on the net_server version of BeOS. - -FFserver is broken (needs poll() implementation). - -There are still issues with errno codes, which are negative in BeOS, and -that FFmpeg negates when returning. This ends up turning errors into -valid results, then crashes. -(To be fixed) - -@chapter Developers Guide - -@section API -@itemize @bullet -@item libavcodec is the library containing the codecs (both encoding and -decoding). Look at @file{libavcodec/apiexample.c} to see how to use it. - -@item libavformat is the library containing the file format handling (mux and -demux code for several formats). Look at @file{ffplay.c} to use it in a -player. See @file{output_example.c} to use it to generate audio or video -streams. - -@end itemize - -@section Integrating libavcodec or libavformat in your program - -You can integrate all the source code of the libraries to link them -statically to avoid any version problem. All you need is to provide a -'config.mak' and a 'config.h' in the parent directory. See the defines -generated by ./configure to understand what is needed. - -You can use libavcodec or libavformat in your commercial program, but -@emph{any patch you make must be published}. The best way to proceed is -to send your patches to the FFmpeg mailing list. - -@node Coding Rules -@section Coding Rules - -FFmpeg is programmed in the ISO C90 language with a few additional -features from ISO C99, namely: -@itemize @bullet -@item -the @samp{inline} keyword; -@item -@samp{//} comments; -@item -designated struct initializers (@samp{struct s x = @{ .i = 17 @};}) -@item -compound literals (@samp{x = (struct s) @{ 17, 23 @};}) -@end itemize - -These features are supported by all compilers we care about, so we will not -accept patches to remove their use unless they absolutely do not impair -clarity and performance. - -All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also -compiles with several other compilers, such as the Compaq ccc compiler -or Sun Studio 9, and we would like to keep it that way unless it would -be exceedingly involved. To ensure compatibility, please do not use any -additional C99 features or GCC extensions. Especially watch out for: -@itemize @bullet -@item -mixing statements and declarations; -@item -@samp{long long} (use @samp{int64_t} instead); -@item -@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar; -@item -GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}). -@end itemize - -Indent size is 4. -The presentation is the one specified by 'indent -i4 -kr -nut'. -The TAB character is forbidden outside of Makefiles as is any -form of trailing whitespace. Commits containing either will be -rejected by the Subversion repository. - -Main priority in FFmpeg is simplicity and small code size (=less -bugs). - -Comments: Use the JavaDoc/Doxygen -format (see examples below) so that code documentation -can be generated automatically. All nontrivial functions should have a comment -above them explaining what the function does, even if it is just one sentence. -All structures and their member variables should be documented, too. -@example -/** - * @@file mpeg.c - * MPEG codec. - * @@author ... - */ - -/** - * Summary sentence. - * more text ... - * ... - */ -typedef struct Foobar@{ - int var1; /**< var1 description */ - int var2; ///< var2 description - /** var3 description */ - int var3; -@} Foobar; - -/** - * Summary sentence. - * more text ... - * ... - * @@param my_parameter description of my_parameter - * @@return return value description - */ -int myfunc(int my_parameter) -... -@end example - -fprintf and printf are forbidden in libavformat and libavcodec, -please use av_log() instead. - -@section Development Policy - -@enumerate -@item - You must not commit code which breaks FFmpeg! (Meaning unfinished but - enabled code which breaks compilation or compiles but does not work or - breaks the regression tests) - You can commit unfinished stuff (for testing etc), but it must be disabled - (#ifdef etc) by default so it does not interfere with other developers' - work. -@item - You do not have to over-test things. If it works for you, and you think it - should work for others, then commit. If your code has problems - (portability, triggers compiler bugs, unusual environment etc) they will be - reported and eventually fixed. -@item - Do not commit unrelated changes together, split them into self-contained - pieces. Also do not forget that if part B depends on part A, but A does not - depend on B, then A can and should be committed first and separate from B. - Keeping changes well split into self-contained parts makes reviewing and - understanding them on the commit log mailing list easier. This also helps - in case of debugging later on. - Also if you have doubts about splitting or not splitting, do not hesitate to - ask/disscuss it on the developer mailing list. -@item - Do not change behavior of the program (renaming options etc) without - first discussing it on the ffmpeg-devel mailing list. Do not remove - functionality from the code. Just improve! - - Note: Redundant code can be removed. -@item - Do not commit changes to the build system (Makefiles, configure script) - which change behavior, defaults etc, without asking first. The same - applies to compiler warning fixes, trivial looking fixes and to code - maintained by other developers. We usually have a reason for doing things - the way we do. Send your changes as patches to the ffmpeg-devel mailing - list, and if the code maintainers say OK, you may commit. This does not - apply to files you wrote and/or maintain. -@item - We refuse source indentation and other cosmetic changes if they are mixed - with functional changes, such commits will be rejected and removed. Every - developer has his own indentation style, you should not change it. Of course - if you (re)write something, you can use your own style, even though we would - prefer if the indentation throughout FFmpeg was consistent (Many projects - force a given indentation style - we do not.). If you really need to make - indentation changes (try to avoid this), separate them strictly from real - changes. - - NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code, - then either do NOT change the indentation of the inner part within (do not - move it to the right)! or do so in a separate commit -@item - Always fill out the commit log message. Describe in a few lines what you - changed and why. You can refer to mailing list postings if you fix a - particular bug. Comments such as "fixed!" or "Changed it." are unacceptable. -@item - If you apply a patch by someone else, include the name and email address in - the log message. Since the ffmpeg-cvslog mailing list is publicly - archived you should add some SPAM protection to the email address. Send an - answer to ffmpeg-devel (or wherever you got the patch from) saying that - you applied the patch. -@item - Do NOT commit to code actively maintained by others without permission. - Send a patch to ffmpeg-devel instead. If noone answers within a reasonable - timeframe (12h for build failures and security fixes, 3 days small changes, - 1 week for big patches) then commit your patch if you think it is OK. - Also note, the maintainer can simply ask for more time to review! -@item - Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits - are sent there and reviewed by all the other developers. Bugs and possible - improvements or general questions regarding commits are discussed there. We - expect you to react if problems with your code are uncovered. -@item - Update the documentation if you change behavior or add features. If you are - unsure how best to do this, send a patch to ffmpeg-devel, the documentation - maintainer(s) will review and commit your stuff. -@item - Try to keep important discussions and requests (also) on the public - developer mailing list, so that all developers can benefit from them. -@item - Never write to unallocated memory, never write over the end of arrays, - always check values read from some untrusted source before using them - as array index or other risky things. -@item - Remember to check if you need to bump versions for the specific libav - parts (libavutil, libavcodec, libavformat) you are changing. You need - to change the version integer and the version string. - Incrementing the first component means no backward compatibility to - previous versions (e.g. removal of a function from the public API). - Incrementing the second component means backward compatible change - (e.g. addition of a function to the public API). - Incrementing the third component means a noteworthy binary compatible - change (e.g. encoder bug fix that matters for the decoder). -@item - If you add a new codec, remember to update the changelog, add it to - the supported codecs table in the documentation and bump the second - component of the @file{libavcodec} version number appropriately. If - it has a fourcc, add it to @file{libavformat/avienc.c}, even if it - is only a decoder. -@item - Do not change code to hide warnings without ensuring that the underlying - logic is correct and thus the warning was inappropriate. -@end enumerate - -We think our rules are not too hard. If you have comments, contact us. - -Note, these rules are mostly borrowed from the MPlayer project. - -@section Submitting patches - -First, (@pxref{Coding Rules}) above if you did not yet. - -When you submit your patch, try to send a unified diff (diff '-up' -option). I cannot read other diffs :-) - -Also please do not submit patches which contain several unrelated changes. -Split them into individual self-contained patches; this makes reviewing -them much easier. - -Run the regression tests before submitting a patch so that you can -verify that there are no big problems. - -Patches should be posted as base64 encoded attachments (or any other -encoding which ensures that the patch will not be trashed during -transmission) to the ffmpeg-devel mailing list, see -@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel} - -It also helps quite a bit if you tell us what the patch does (for example -'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant -and has no lrint()') - -@section Patch review process - -All patches posted to ffmpeg-devel will be reviewed, unless they contain a -clear note that the patch is not for SVN. -Reviews and comments will be posted as replies to the patch on the -mailing list. The patch submitter then has to take care of every comment, -that can be by resubmitting a changed patch or by disscussion. Resubmitted -patches will themselves be reviewed like any other patch. If at some point -a patch passes review with no comments then it is approved, that can for -simple and small patches happen immediately while large patches will generally -have to be changed and reviewed many times before they are approved. -After a patch is approved it will be committed to the repository. - -We will review all submitted patches, but sometimes we are quite busy so -especially for large patches this can take several weeks. - -When resubmitting patches, please do not make any significant changes -not related to the comments received during review. Such patches will -be rejected. Instead, submit significant changes or new features as -separate patches. - -@section Regression tests - -Before submitting a patch (or committing to the repository), you should at least -test that you did not break anything. - -The regression tests build a synthetic video stream and a synthetic -audio stream. These are then encoded and decoded with all codecs or -formats. The CRC (or MD5) of each generated file is recorded in a -result file. A 'diff' is launched to compare the reference results and -the result file. - -The regression tests then go on to test the FFserver code with a -limited set of streams. It is important that this step runs correctly -as well. - -Run 'make test' to test all the codecs and formats. - -Run 'make fulltest' to test all the codecs, formats and FFserver. - -[Of course, some patches may change the results of the regression tests. In -this case, the reference results of the regression tests shall be modified -accordingly]. - -@bye |