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author | Diego Biurrun <diego@biurrun.de> | 2005-08-05 01:06:04 +0000 |
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committer | Diego Biurrun <diego@biurrun.de> | 2005-08-05 01:06:04 +0000 |
commit | 4c5f7207bf15cc2c560a034e985d5aafce1e8af1 (patch) | |
tree | 4e1cba5f8549d14e48a9a556540eb1d67a9e836c /doc | |
parent | 804b0dac587a3979ed17c1ef1d24a7fe363ecaf0 (diff) | |
download | ffmpeg-4c5f7207bf15cc2c560a034e985d5aafce1e8af1.tar.gz |
spelling/grammar/wording
Originally committed as revision 4492 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'doc')
-rw-r--r-- | doc/ffmpeg-doc.texi | 553 |
1 files changed, 279 insertions, 274 deletions
diff --git a/doc/ffmpeg-doc.texi b/doc/ffmpeg-doc.texi index 362a5bb80b..8101ff927b 100644 --- a/doc/ffmpeg-doc.texi +++ b/doc/ffmpeg-doc.texi @@ -14,8 +14,9 @@ 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 the parameters, when -possible. You have usually to give only the target bitrate you want. +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. @@ -33,18 +34,18 @@ ffmpeg /tmp/out.mpg @end example Note that you must activate the right video source and channel before -launching ffmpeg. You can use any TV viewer such as xawtv -(@url{http://bytesex.org/xawtv/}) by Gerd Knorr which I find very -good. You must also set correctly the audio recording levels with a +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 Video and Audio file format conversion -* ffmpeg can use any supported file format and protocol as input: +* FFmpeg can use any supported file format and protocol as input: Examples: -* You can input from YUV files: +* You can use YUV files as input: @example ffmpeg -i /tmp/test%d.Y /tmp/out.mpg @@ -59,19 +60,19 @@ It will use the files: 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. +if FFmpeg cannot guess it. -* You can input from a RAW YUV420P file: +* You can input from a raw YUV420P file: @example ffmpeg -i /tmp/test.yuv /tmp/out.avi @end example -The RAW YUV420P is a file containing RAW YUV planar, for each frame first -come the Y plane followed by U and V planes, which are half vertical and +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: +* You can output to a raw YUV420P file: @example ffmpeg -i mydivx.avi -o hugefile.yuv @@ -83,8 +84,8 @@ ffmpeg -i mydivx.avi -o hugefile.yuv ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg @end example -Convert the audio file a.wav and the raw YUV video file a.yuv -to MPEG file a.mpg +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: @@ -92,7 +93,7 @@ to MPEG file a.mpg ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2 @end example -Convert the sample rate of a.wav to 22050 Hz and encode it to MPEG audio. +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: @@ -101,8 +102,8 @@ mapping from input stream to output streams: ffmpeg -i /tmp/a.wav -ab 64 /tmp/a.mp2 -ab 128 /tmp/b.mp2 -map 0:0 -map 0:0 @end example -Convert a.wav to a.mp2 at 64 kbits and b.mp2 at 128 kbits. '-map -file:index' specify which input stream is used for each output +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 @@ -111,16 +112,16 @@ stream, in the order of the definition of output streams. ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800 -g 300 -bf 2 -acodec mp3 -ab 128 snatch.avi @end example -This is a typical DVD ripper example, input from a VOB file, output -to 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, GOP -size is 300 that means an INTRA frame every 10 seconds for 29.97 fps -input video. Also the audio stream is MP3 encoded so you need LAME -support which is enabled using @code{--enable-mp3lame} when -configuring. The mapping is particularly useful for DVD transcoding +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}. +NOTE: To see the supported input formats, use @code{ffmpeg -formats}. @c man end @chapter Invocation @@ -139,11 +140,11 @@ If no input file is given, audio/video grabbing is done. As a general rule, options are applied to the next specified file. For example, if you give the @option{-b 64} option, it sets the video -bitrate of the next file. Format option may be needed for raw input +bitrate of the next file. 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 parameter for the outputs as the one +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 @@ -152,68 +153,69 @@ specified for the inputs. @table @option @item -L -show license +Show license. @item -h -show help +Show help. @item -formats -show available formats, codecs, protocols, ... +Show available formats, codecs, protocols, ... @item -f fmt -force format +Force format. @item -i filename -input file name +input filename @item -y -overwrite output files +Overwrite output files. @item -t duration -set the recording time in seconds. @code{hh:mm:ss[.xxx]} syntax is also -supported. +Set the recording time in seconds. +@code{hh:mm:ss[.xxx]} syntax is also supported. @item -ss position -seek to given time position. @code{hh:mm:ss[.xxx]} syntax is also -supported. +Seek to given time position in seconds. +@code{hh:mm:ss[.xxx]} syntax is also supported. @item -title string -set the title +Set the title. @item -author string -set the author +Set the author. @item -copyright string -set the copyright +Set the copyright. @item -comment string -set the comment +Set the comment. @item -target type -specify target file type ("vcd", "svcd", "dvd", "dv", "pal-vcd", "ntsc-svcd", ... ). All the format -options (bitrate, codecs, buffer sizes) are automatically set by this -option. You can just type: +Specify target file type ("vcd", "svcd", "dvd", "dv", "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 compromise the -standard, as in: +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 -hq -activate high quality settings +Activate high quality settings. @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 input files' timestamps; -specifying a positive offset means that the corresponding streams are -delayed by 'offset' seconds. +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. @end table @@ -221,12 +223,12 @@ delayed by 'offset' seconds. @table @option @item -b bitrate -set the video bitrate in kbit/s (default = 200 kb/s) +Set the video bitrate in kbit/s (default = 200 kb/s). @item -r fps -set frame rate (default = 25) +Set frame rate (default = 25). @item -s size -set frame size. The format is @samp{WxH} (default 160x128). The -following abbreviations are recognized: +Set frame size. The format is @samp{wxh} (default = 160x128). +The following abbreviations are recognized: @table @samp @item sqcif 128x96 @@ -239,51 +241,52 @@ following abbreviations are recognized: @end table @item -aspect aspect -set aspect ratio (4:3, 16:9 or 1.3333, 1.7777) +Set aspect ratio (4:3, 16:9 or 1.3333, 1.7777). @item -croptop size -set top crop band size (in pixels) +Set top crop band size (in pixels). @item -cropbottom size -set bottom crop band size (in pixels) +Set bottom crop band size (in pixels). @item -cropleft size -set left crop band size (in pixels) +Set left crop band size (in pixels). @item -cropright size -set right crop band size (in pixels) +Set right crop band size (in pixels). @item -padtop size -set top pad band size (in pixels) +Set top pad band size (in pixels). @item -padbottom size -set bottom pad band size (in pixels) +Set bottom pad band size (in pixels). @item -padleft size -set left pad band size (in pixels) +Set left pad band size (in pixels). @item -padright size -set right pad band size (in pixels) +Set right pad band size (in pixels). @item -padcolor (hex color) -set color of padded bands. The value for pad color is expressed -as a six digit hexadecimal number where the first two digits represent red, -middle two digits green and last two digits blue. Defaults to 000000 (black) +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 +Disable video recording. @item -bt tolerance -set video bitrate tolerance (in kbit/s) +Set video bitrate tolerance (in kbit/s). @item -maxrate bitrate -set max video bitrate tolerance (in kbit/s) +Set max video bitrate tolerance (in kbit/s). @item -minrate bitrate -set min video bitrate tolerance (in kbit/s) +Set min video bitrate tolerance (in kbit/s). @item -bufsize size -set ratecontrol buffer size (in kbit) +Set rate control buffer size (in kbit). @item -vcodec codec -force video codec to @var{codec}. Use the @code{copy} special value to +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) +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 at the exact requested bit rate is generated in the second -pass. +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 -select two pass log file name to @var{file}. +Set two pass logfile name to @var{file}. @end table @@ -291,40 +294,40 @@ select two pass log file name to @var{file}. @table @option @item -g gop_size -set the group of picture size +Set the group of pictures size. @item -intra -use only intra frames +Use only intra frames. @item -qscale q -use fixed video quantiser scale (VBR) +Use fixed video quantiser scale (VBR). @item -qmin q -min video quantiser scale (VBR) +minimum video quantiser scale (VBR) @item -qmax q -max video quantiser scale (VBR) +maximum video quantiser scale (VBR) @item -qdiff q -max difference between the quantiser scale (VBR) +maximum difference between the quantiser scales (VBR) @item -qblur blur video quantiser scale blur (VBR) @item -qcomp compression video quantiser scale compression (VBR) @item -rc_init_cplx complexity -initial complexity for 1-pass encoding +initial complexity for single pass encoding @item -b_qfactor factor -qp factor between p and b frames +qp factor between P- and B-frames @item -i_qfactor factor -qp factor between p and i frames +qp factor between P- and I-frames @item -b_qoffset offset -qp offset between p and b frames +qp offset between P- and B-frames @item -i_qoffset offset -qp offset between p and i frames +qp offset between P- and I-frames @item -rc_eq equation -set rate control equation (@pxref{FFmpeg formula -evaluator}). Default is @code{tex^qComp}. +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 lower to best quality): +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. @@ -338,7 +341,7 @@ exhaustive search (slow and marginally better than epzs) @end table @item -dct_algo algo -set DCT algorithm to @var{algo}. Available values are: +Set DCT algorithm to @var{algo}. Available values are: @table @samp @item 0 FF_DCT_AUTO (default) @@ -355,7 +358,7 @@ FF_DCT_ALTIVEC @end table @item -idct_algo algo -set IDCT algorithm to @var{algo}. Available values are: +Set IDCT algorithm to @var{algo}. Available values are: @table @samp @item 0 FF_IDCT_AUTO (default) @@ -382,7 +385,7 @@ FF_IDCT_SIMPLEARM @end table @item -er n -set error resilience to @var{n}. +Set error resilience to @var{n}. @table @samp @item 1 FF_ER_CAREFULL (default) @@ -395,55 +398,55 @@ 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 +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) +FF_EC_GUESS_MVS (default = enabled) @item 2 -FF_EC_DEBLOCK (default=enabled) +FF_EC_DEBLOCK (default = enabled) @end table @item -bf frames -use 'frames' B frames (supported for MPEG-1, MPEG-2 and MPEG-4) +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) +FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in FFmpeg). @item 1 -FF_MB_DECISION_BITS: chooses the one which needs the fewest bits +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 (only MPEG-4) +Use four motion vector by macroblock (MPEG-4 only). @item -part -use data partitioning (only MPEG-4) +Use data partitioning (MPEG-4 only). @item -bug param -workaround not auto detected encoder bugs +Work around encoder bugs that are not auto-detected. @item -strict strictness -how strictly to follow the standards +How strictly to follow the standards. @item -aic -enable Advanced intra coding (h263+) +Enable Advanced intra coding (h263+). @item -umv -enable Unlimited Motion Vector (h263+) +Enable Unlimited Motion Vector (h263+) @item -deinterlace -deinterlace pictures +Deinterlace pictures. @item -interlace -force interlacing support in encoder (only MPEG-2 and MPEG-4). Use this option -if your input file is interlaced and if you want to keep the interlaced -format for minimum losses. The alternative is to deinterlace the input -stream with @option{-deinterlace}, but deinterlacing introduces more -losses. +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 +Calculate PSNR of compressed frames. @item -vstats -dump video coding statistics to @file{vstats_HHMMSS.log}. +Dump video coding statistics to @file{vstats_HHMMSS.log}. @item -vhook module -insert video processing @var{module}. @var{module} contains the module +Insert video processing @var{module}. @var{module} contains the module name and its parameters separated by spaces. @end table @@ -451,56 +454,56 @@ name and its parameters separated by spaces. @table @option @item -ar freq -set the audio sampling frequency (default = 44100 Hz) +Set the audio sampling frequency (default = 44100 Hz). @item -ab bitrate -set the audio bitrate in kbit/s (default = 64) +Set the audio bitrate in kbit/s (default = 64). @item -ac channels -set the number of audio channels (default = 1) +Set the number of audio channels (default = 1). @item -an -disable audio recording +Disable audio recording. @item -acodec codec -force audio codec to @var{codec}. Use the @code{copy} special value to -tell that the raw codec data must be copied as is. +Force audio codec to @var{codec}. Use the @code{copy} special value to +specify that the raw codec data must be copied as is. @end table @section Audio/Video grab options @table @option @item -vd device -set video grab device (e.g. @file{/dev/video0}) +sEt video grab device (e.g. @file{/dev/video0}). @item -vc channel -set video grab channel (DV1394 only) +Set video grab channel (DV1394 only). @item -tvstd standard -set television standard (NTSC, PAL (SECAM)) +Set television standard (NTSC, PAL (SECAM)). @item -dv1394 -set DV1394 grab +Set DV1394 grab. @item -ad device -set audio device (e.g. @file{/dev/dsp}) +Set audio device (e.g. @file{/dev/dsp}). @end table @section Advanced options @table @option @item -map file:stream -set input stream mapping +Set input stream mapping. @item -debug -print specific debug info +Print specific debug info. @item -benchmark -add timings for benchmarking +Add timings for benchmarking. @item -hex -dump each input packet +Dump each input packet. @item -bitexact -only use bit exact algorithms (for codec testing) +Only use bit exact algorithms (for codec testing). @item -ps size -set packet size in bits +Set packet size in bits. @item -re -read input at native frame rate. Mainly used to simulate a grab device. +Read input at native frame rate. Mainly used to simulate a grab device. @item -loop -loop over the input stream. Currently it works only for image -streams. This option is used for ffserver automatic testing. +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 -(Zero will loop the output infinitely) +(0 will loop the output infinitely). @end table @node FFmpeg formula evaluator @@ -580,22 +583,22 @@ Fabrice Bellard @section Protocols -The filename can be @file{-} to read from the standard input or to write -to the standard output. +The filename can be @file{-} to read from standard input or to write +to standard output. -ffmpeg handles also many protocols specified with the URL syntax. +FFmpeg also handles many protocols specified with an URL syntax. -Use 'ffmpeg -formats' to have a list of the supported protocols. +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 +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 bit rate application, use a low frame rate -and a small GOP size. This is especially true for real video where +@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: @@ -604,19 +607,19 @@ ffmpeg -g 3 -r 3 -t 10 -b 50 -s qcif -f rv10 /tmp/b.rm @end example @item The parameter 'q' which is displayed while encoding is the current -quantizer. The value of 1 indicates that a very good quality could -be achieved. The value of 31 indicates the worst quality. If q=31 +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 bit rate. You must either increase the bit rate, decrease the +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 -completely motion estimation (you have only I frames, which means it +motion estimation completely (you have only I-frames, which means it is about as good as JPEG compression). -@item To have very low bitrates in audio, reduce the sampling frequency +@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 @@ -624,8 +627,8 @@ is about as good as JPEG compression). quality). @item When converting video files, you can use the '-sameq' option which -uses in the encoder the same quality factor than in the decoder. It -allows to be almost lossless in encoding. +uses the same quality factor in the encoder as in the decoder. +It allows almost lossless encoding. @end itemize @@ -641,17 +644,17 @@ library: @multitable @columnfractions .4 .1 .1 @item Supported File Format @tab Encoding @tab Decoding @tab Comments @item MPEG audio @tab X @tab X -@item MPEG1 systems @tab X @tab X +@item MPEG-1 systems @tab X @tab X @tab muxed audio and video -@item MPEG2 PS @tab X @tab X +@item MPEG-2 PS @tab X @tab X @tab also known as @code{VOB} file -@item MPEG2 TS @tab @tab X +@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 +@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 @@ -664,38 +667,38 @@ library: @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 MPEG4 @tab X @tab X -@tab MPEG4 is a variant of QuickTime +@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 +@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 +@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 +@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 +@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 +@tab Used in many Sega Saturn console games. @item Westwood Studios VQA/AUD @tab @tab X -@tab Multimedia formats used in Westwood Studios games +@tab Multimedia formats used in Westwood Studios games. @item Id Cinematic (.cin) @tab @tab X -@tab Used in Quake II +@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 +@tab Used in Sierra CD-ROM games. @item Sierra Online @tab @tab X -@tab .sol files used in Sierra Online games +@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 +@tab Used in various EA games; files have extensions like WVE and UV2. @item Nullsoft Video (NSV) format @tab @tab X @end multitable -@code{X} means that the encoding (resp. decoding) is supported. +@code{X} means that encoding (resp. decoding) is supported. @section Image Formats @@ -705,40 +708,40 @@ following image formats are supported: @multitable @columnfractions .4 .1 .1 @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 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 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 SGI @tab X @tab X @tab SGI RGB image format @end multitable -@code{X} means that the encoding (resp. decoding) is supported. +@code{X} means that encoding (resp. decoding) is supported. @section Video Codecs @multitable @columnfractions .4 .1 .1 .7 @item Supported Codec @tab Encoding @tab Decoding @tab Comments -@item MPEG1 video @tab X @tab X -@item MPEG2 video @tab X @tab X -@item MPEG4 @tab X @tab X @tab Also known as DivX4/5 +@item MPEG-1 video @tab X @tab X +@item MPEG-2 video @tab X @tab X +@item MPEG-4 @tab X @tab X @tab also known as DivX4/5 @item MSMPEG4 V1 @tab X @tab X @item MSMPEG4 V2 @tab X @tab X -@item MSMPEG4 V3 @tab X @tab X @tab Also known as DivX3 +@item MSMPEG4 V3 @tab X @tab X @tab also known as DivX3 @item WMV7 @tab X @tab X -@item WMV8 @tab X @tab X @tab Not completely working +@item WMV8 @tab X @tab X @tab not completely working @item H.261 @tab X @tab X -@item H.263(+) @tab X @tab X @tab Also known as Real Video 1.0 +@item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0 @item H.264 @tab @tab X @item MJPEG @tab X @tab X -@item Lossless MJPEG @tab X @tab X +@item lossless MJPEG @tab X @tab X @item Apple MJPEG-B @tab @tab X @item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X @item DV @tab X @tab X -@item Huff YUV @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 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 @@ -751,11 +754,11 @@ following image formats are supported: @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 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 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 @@ -764,11 +767,11 @@ following image formats are supported: @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 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 VMD Video @tab @tab X @tab used in Sierra VMD files +@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 @@ -781,11 +784,11 @@ following image formats are supported: @item Fraps FPS1 @tab @tab X @tab @end multitable -@code{X} means that the encoding (resp. decoding) is supported. +@code{X} means that encoding (resp. decoding) is supported. -Check at @url{http://www.mplayerhq.hu/~michael/codec-features.html} to -get a precise comparison of FFmpeg MPEG4 codec compared to the other -solutions. +See @url{http://www.mplayerhq.hu/~michael/codec-features.html} to +get a precise comparison of the FFmpeg MPEG-4 codec compared to +other implementations. @section Audio Codecs @@ -793,52 +796,52 @@ solutions. @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 +@tab MP3 encoding is supported through the external library LAME. @item AC3 @tab IX @tab IX -@tab liba52 is used internally for decoding +@tab liba52 is used internally for decoding. @item Vorbis @tab X @tab X -@tab supported through the external library libvorbis +@tab Supported through the external library libvorbis. @item WMA V1/V2 @tab @tab X @item AAC @tab X @tab X -@tab supported through the external library libfaac/libfaad +@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 +@tab Used in some Sega Saturn console games. @item Duck DK4 IMA ADPCM @tab @tab X -@tab used in some Sega Saturn console games +@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 +@tab Used in Westwood Studios games like Command and Conquer. @item SMJPEG IMA ADPCM @tab @tab X -@tab used in certain Loki game ports +@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 +@tab Used in Sega Dreamcast games. @item Electronic Arts ADPCM @tab @tab X -@tab used in various EA titles +@tab Used in various EA titles. @item Creative ADPCM @tab @tab X @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 +@tab Real low bitrate AC3 codec, liba52 is used for decoding. @item AMR-NB @tab X @tab X -@tab supported through an external library +@tab Supported through an external library. @item AMR-WB @tab X @tab X -@tab supported through an external library +@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 +@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 +@tab Used in various Interplay computer games. @item Xan DPCM @tab @tab X -@tab used in Origin's Wing Commander IV AVI files +@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 +@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 @@ -846,20 +849,20 @@ solutions. @item Apple lossless audio @tab @tab X @tab QuickTime fourcc 'alac' @item FFmpeg Sonic @tab X @tab X -@tab Experimental lossy/lossless codec +@tab experimental lossy/lossless codec @end multitable -@code{X} means that the encoding (resp. decoding) is supported. +@code{X} means that encoding (resp. decoding) is supported. -@code{I} means that an integer only version is available too (ensures highest -performances on systems without hardware floating point support). +@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 Linux -ffmpeg should be compiled with at least GCC 2.95.3. GCC 3.2 is the -preferred compiler now for ffmpeg. All future optimizations will depend on +FFmpeg should be compiled with at least GCC 2.95.3. GCC 3.2 is the +preferred compiler now for FFmpeg. All future optimizations will depend on features only found in GCC 3.2. @section BSD @@ -873,26 +876,28 @@ features only found in GCC 3.2. @url{http://www.mingw.org/}. You can find detailed installation instructions in the download section and the FAQ. -@item If you want to test the FFmpeg Simple Media Player, also download +@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 place, and +@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 (the latest release version or the current CVS snapshot whichever is recommended). +@item Extract the current version of FFmpeg (the latest release version or +the current CVS snapshot, whichever is recommended). @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 +@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}. Don't forget to copy @file{SDL.dll} at the place you launch -@file{ffplay}. +@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing +@file{make install}. Don't forget to copy @file{SDL.dll} to the place +you launch @file{ffplay} from. @end itemize @@ -901,18 +906,18 @@ Notes: @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 in the ffmpeg directory in order to build the +must be copied to the FFmpeg directory in order to build the installer. -@item By using @code{./configure --enable-shared} when configuring ffmpeg, +@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, then FFmpeg tries to use the Microsoft Visual +@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{avformat.lib}. With these libraries you can link your Visual C++ code directly with the FFmpeg DLLs. @end itemize @@ -922,14 +927,14 @@ code directly with the FFmpeg DLLs. You must use the MinGW cross compilation tools available at @url{http://www.mingw.org/}. -Then configure ffmpeg with the following options: +Then configure FFmpeg with the following options: @example ./configure --enable-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 +Then you can easily test FFmpeg with Wine (@url{http://www.winehq.com/}). @section Mac OS X @@ -945,12 +950,12 @@ Old stuff: François Revol - revol at free dot fr - April 2002 The configure script should guess the configuration itself, -however I still didn't tested building on net_server version of BeOS. +however I still didn't test building on the net_server version of BeOS. -ffserver is broken (needs poll() implementation). +FFserver is broken (needs poll() implementation). -There is still issues with errno codes, which are negative in BeOS, and -that ffmpeg negates when returning. This ends up turning errors into +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) @@ -959,10 +964,10 @@ valid results, then crashes. @section API @itemize @item libavcodec is the library containing the codecs (both encoding and - decoding). See @file{libavcodec/apiexample.c} to see how to use it. +decoding). Look at @file{libavcodec/apiexample.c} to see how to use it. -@item libavformat is the library containing the file formats handling (mux and - demux code for several formats). See @file{ffplay.c} to use it in a +@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. @@ -977,12 +982,12 @@ 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. +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 +FFmpeg is programmed in the ISO C90 language with a few additional features from ISO C99, namely: @itemize @bullet @item @@ -999,11 +1004,11 @@ These features are supported by all compilers we care about, so we won't accept patches to remove their use unless they absolutely don't impair clarity and performance. -All code must compile with GCC 2.95 and GCC 3.3. Currently, ffmpeg also +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 don't use any -additional C99 features or GCC extensions. Watch out especially for: +additional C99 features or GCC extensions. Especially watch out for: @itemize @bullet @item mixing statements and declarations; @@ -1018,18 +1023,18 @@ GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}). Indent size is 4. The TAB character should not be used. The presentation is the one specified by 'indent -i4 -kr'. -Main priority in ffmpeg is simplicity and small code size (=less +Main priority in FFmpeg is simplicity and small code size (=less bugs). -Comments: use the JavaDoc/Doxygen -format (see examples below) so that a documentation -can be generated automatically. All non trivial functions should have a comment -above it explaining what the function does, even if its just one sentence. -All Structures and their member variables should be documented too. +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's just one sentence. +All structures and their member variables should be documented, too. @example /** * @@file mpeg.c - * mpeg codec. + * MPEG codec. * @@author ... */ @@ -1065,15 +1070,15 @@ please use av_log() instead. @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 + 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 don't have to over-test things. If it works for you, and you think it - should work for others, too, then commit. If your code has problems - (portability, exploits compiler bugs, unusual environment etc) they will be + 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 @@ -1083,7 +1088,7 @@ please use av_log() instead. first discussing it on the ffmpeg-devel mailing list. Do not remove functionality from the code. Just improve! - Note: Redundant code can be removed + 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 @@ -1097,8 +1102,8 @@ please use av_log() instead. 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 would be consistent (Many projects - force a given indentation style - we don't.) If you really need to make + prefer if the indentation throughout FFmpeg was consistent (Many projects + force a given indentation style - we don't.). If you really need to make indentation changes (try to avoid this), separate them strictly from real changes. @@ -1136,9 +1141,9 @@ please use av_log() instead. Never revert changes made a long time ago or buggy code. Fix it in the normal way instead. @item - Never write to not allocated memory, never write over the end of arrays, - always check values read from some untrusted source before using them as index - into an array or otherwise risky things. + 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. @end enumerate We think our rules are not too hard. If you have comments, contact us. @@ -1164,38 +1169,38 @@ 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 wont be trashed during +encoding which ensures that the patch won't be trashed during transmission) to the ffmpeg-devel mailing list, see @url{http://www1.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 +'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant and has no lrint()') -We reply to all patches submitted and either apply or reject with some -explanation why, but sometimes we are quite busy so it can take a week or 2 +We reply to all submitted patches and either apply or reject with some +explanation why, but sometimes we are quite busy so it can take a week or two. @section Regression tests -Before submitting a patch (or committing with CVS), you should at least +Before submitting a patch (or committing to CVS), you should at least test that you did not break anything. -The regression test build a synthetic video stream and a synthetic -audio stream. Then these are encoded then decoded with all codecs or +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. Then a 'diff' is launched with the reference results and +result file. A 'diff' is launched to compare the reference results and the result file. -The regression test then goes on to test the ffserver code with a +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. +Run 'make fulltest' to test all the codecs, formats and FFserver. -[Of course, some patches may change the regression tests results. In -this case, the regression tests reference results shall be modified +[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 |