documentation for X11 grabbing
[libav.git] / doc / ffmpeg-doc.texi
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1\input texinfo @c -*- texinfo -*-
2
3@settitle FFmpeg Documentation
4@titlepage
5@sp 7
6@center @titlefont{FFmpeg Documentation}
7@sp 3
8@end titlepage
9
10
11@chapter Introduction
12
13FFmpeg is a very fast video and audio converter. It can also grab from
14a live audio/video source.
115329f1 15
9181577c 16The command line interface is designed to be intuitive, in the sense
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17that FFmpeg tries to figure out all parameters that can possibly be
18derived automatically. You usually only have to specify the target
19bitrate you want.
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20
21FFmpeg can also convert from any sample rate to any other, and resize
22video on the fly with a high quality polyphase filter.
23
24@chapter Quick Start
25
e99c4e10 26@c man begin EXAMPLES
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27@section Video and Audio grabbing
28
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29FFmpeg can use a video4linux compatible video source and any Open Sound
30System audio source:
31
9181577c 32@example
115329f1 33ffmpeg /tmp/out.mpg
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34@end example
35
e99c4e10 36Note that you must activate the right video source and channel before
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37launching FFmpeg with any TV viewer such as xawtv
38(@url{http://bytesex.org/xawtv/}) by Gerd Knorr. You also
39have to set the audio recording levels correctly with a
e99c4e10 40standard mixer.
9181577c 41
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42@section X11 grabbing
43
44FFmpeg can grab X11 display.
45
46@example
47ffmpeg -f x11grab -vd x11:0.0 /tmp/out.mpg
48@end example
49
500.0 is display.screen numbers of your X11 server.
51You can check $DISPLAY variable.
52
6bf40f39 53@section Video and Audio file format conversion
9181577c 54
4c5f7207 55* FFmpeg can use any supported file format and protocol as input:
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56
57Examples:
58
4c5f7207 59* You can use YUV files as input:
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60
61@example
115329f1 62ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
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63@end example
64
115329f1 65It will use the files:
9181577c 66@example
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67/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
68/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
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69@end example
70
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71The Y files use twice the resolution of the U and V files. They are
72raw files, without header. They can be generated by all decent video
73decoders. You must specify the size of the image with the @option{-s} option
4c5f7207 74if FFmpeg cannot guess it.
9181577c 75
4c5f7207 76* You can input from a raw YUV420P file:
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77
78@example
e99c4e10 79ffmpeg -i /tmp/test.yuv /tmp/out.avi
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80@end example
81
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82test.yuv is a file containing raw YUV planar data. Each frame is composed
83of the Y plane followed by the U and V planes at half vertical and
e99c4e10 84horizontal resolution.
9181577c 85
4c5f7207 86* You can output to a raw YUV420P file:
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87
88@example
f926cbe7 89ffmpeg -i mydivx.avi hugefile.yuv
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90@end example
91
92* You can set several input files and output files:
93
94@example
e99c4e10 95ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
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96@end example
97
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98Converts the audio file a.wav and the raw YUV video file a.yuv
99to MPEG file a.mpg.
9181577c 100
6bf40f39 101* You can also do audio and video conversions at the same time:
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102
103@example
e99c4e10 104ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
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105@end example
106
4c5f7207 107Converts a.wav to MPEG audio at 22050Hz sample rate.
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108
109* You can encode to several formats at the same time and define a
e99c4e10 110mapping from input stream to output streams:
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111
112@example
e99c4e10 113ffmpeg -i /tmp/a.wav -ab 64 /tmp/a.mp2 -ab 128 /tmp/b.mp2 -map 0:0 -map 0:0
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114@end example
115
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116Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
117file:index' specifies which input stream is used for each output
e99c4e10 118stream, in the order of the definition of output streams.
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119
120* You can transcode decrypted VOBs
121
122@example
3c0ba870 123ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800k -g 300 -bf 2 -acodec mp3 -ab 128 snatch.avi
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124@end example
125
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126This is a typical DVD ripping example; the input is a VOB file, the
127output an AVI file with MPEG-4 video and MP3 audio. Note that in this
128command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
129GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
130input video. Furthermore, the audio stream is MP3-encoded so you need
131to enable LAME support by passing @code{--enable-mp3lame} to configure.
132The mapping is particularly useful for DVD transcoding
e99c4e10 133to get the desired audio language.
9181577c 134
4c5f7207 135NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
e99c4e10 136@c man end
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137
138@chapter Invocation
139
140@section Syntax
141
e99c4e10 142The generic syntax is:
9181577c 143
115329f1 144@example
e99c4e10 145@c man begin SYNOPSIS
28f88dc8 146ffmpeg [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}...
e99c4e10 147@c man end
9181577c 148@end example
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149@c man begin DESCRIPTION
150If no input file is given, audio/video grabbing is done.
9181577c 151
e99c4e10 152As a general rule, options are applied to the next specified
699e77b1 153file. Therefore, order is important, and you can have the same
8cc62264 154option on the command line multiple times. Each occurrence is
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155then applied to the next input or output file.
156
eb10acec 157* To set the video bitrate of the output file to 64kbit/s:
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158@example
159ffmpeg -i input.avi -b 64k output.avi
160@end example
161
162* To force the frame rate of the input and output file to 24 fps:
163@example
164ffmpeg -r 24 -i input.avi output.avi
165@end example
166
167* To force the frame rate of the output file to 24 fps:
168@example
169ffmpeg -i input.avi -r 24 output.avi
170@end example
171
172* To force the frame rate of input file to 1 fps and the output file to 24 fps:
173@example
174ffmpeg -r 1 -i input.avi -r 24 output.avi
175@end example
176
177The format option may be needed for raw input files.
9181577c 178
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179By default, FFmpeg tries to convert as losslessly as possible: It
180uses the same audio and video parameters for the outputs as the one
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181specified for the inputs.
182@c man end
9181577c 183
e99c4e10 184@c man begin OPTIONS
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185@section Main options
186
e99c4e10 187@table @option
9181577c 188@item -L
4c5f7207 189Show license.
18bff752 190
9181577c 191@item -h
4c5f7207 192Show help.
18bff752 193
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194@item -version
195Show version.
196
e99c4e10 197@item -formats
4c5f7207 198Show available formats, codecs, protocols, ...
18bff752 199
115329f1 200@item -f fmt
4c5f7207 201Force format.
18bff752 202
115329f1 203@item -i filename
4c5f7207 204input filename
9181577c 205
115329f1 206@item -y
4c5f7207 207Overwrite output files.
9181577c 208
115329f1 209@item -t duration
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210Set the recording time in seconds.
211@code{hh:mm:ss[.xxx]} syntax is also supported.
9181577c 212
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213@item -fs limit_size
214Set the file size limit.
215
e83a84ac 216@item -ss position
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217Seek to given time position in seconds.
218@code{hh:mm:ss[.xxx]} syntax is also supported.
e83a84ac 219
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220@item -itsoffset offset
221Set the input time offset in seconds.
222@code{[-]hh:mm:ss[.xxx]} syntax is also supported.
223This option affects all the input files that follow it.
224The offset is added to the timestamps of the input files.
225Specifying a positive offset means that the corresponding
226streams are delayed by 'offset' seconds.
227
115329f1 228@item -title string
4c5f7207 229Set the title.
9181577c 230
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231@item -timestamp time
232Set the timestamp.
233
115329f1 234@item -author string
4c5f7207 235Set the author.
9181577c 236
115329f1 237@item -copyright string
4c5f7207 238Set the copyright.
9181577c 239
115329f1 240@item -comment string
4c5f7207 241Set the comment.
9181577c 242
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243@item -album string
244Set the album.
245
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246@item -track number
247Set the track.
248
249@item -year number
250Set the year.
251
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252@item -v verbose
253Control amount of logging.
254
99db6420 255@item -target type
4386f941 256Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50", "pal-vcd",
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257"ntsc-svcd", ... ). All the format options (bitrate, codecs,
258buffer sizes) are then set automatically. You can just type:
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259
260@example
261ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
262@end example
263
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264Nevertheless you can specify additional options as long as you know
265they do not conflict with the standard, as in:
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266
267@example
268ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
269@end example
270
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271@item -dframes number
272Set the number of data frames to record.
273
274@item -scodec codec
275Force subtitle codec ('copy' to copy stream).
276
277@item -newsubtitle
278Add a new subtitle stream to the current output stream.
279
280@item -slang code
281Set the ISO 639 language code (3 letters) of the current subtitle stream.
401fbdde 282
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283@end table
284
285@section Video Options
286
e99c4e10 287@table @option
9181577c 288@item -b bitrate
3c0ba870 289Set the video bitrate in bit/s (default = 200 kb/s).
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290@item -vframes number
291Set the number of video frames to record.
115329f1 292@item -r fps
4386f941 293Set frame rate (Hz value, fraction or abbreviation), (default = 25).
115329f1 294@item -s size
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295Set frame size. The format is @samp{wxh} (default = 160x128).
296The following abbreviations are recognized:
5ee03c86 297@table @samp
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298@item sqcif
299128x96
300@item qcif
301176x144
302@item cif
303352x288
304@item 4cif
305704x576
306@end table
307
308@item -aspect aspect
4c5f7207 309Set aspect ratio (4:3, 16:9 or 1.3333, 1.7777).
18bff752 310@item -croptop size
4c5f7207 311Set top crop band size (in pixels).
18bff752 312@item -cropbottom size
4c5f7207 313Set bottom crop band size (in pixels).
18bff752 314@item -cropleft size
4c5f7207 315Set left crop band size (in pixels).
18bff752 316@item -cropright size
4c5f7207 317Set right crop band size (in pixels).
1ff93ffc 318@item -padtop size
4c5f7207 319Set top pad band size (in pixels).
1ff93ffc 320@item -padbottom size
4c5f7207 321Set bottom pad band size (in pixels).
1ff93ffc 322@item -padleft size
4c5f7207 323Set left pad band size (in pixels).
1ff93ffc 324@item -padright size
4c5f7207 325Set right pad band size (in pixels).
5b79a73e 326@item -padcolor (hex color)
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327Set color of padded bands. The value for padcolor is expressed
328as a six digit hexadecimal number where the first two digits
329represent red, the middle two digits green and last two digits
330blue (default = 000000 (black)).
9181577c 331@item -vn
4c5f7207 332Disable video recording.
115329f1 333@item -bt tolerance
dc5ee8bc 334Set video bitrate tolerance (in bit/s).
18bff752 335@item -maxrate bitrate
a5515106 336Set max video bitrate tolerance (in bit/s).
18bff752 337@item -minrate bitrate
a5515106 338Set min video bitrate tolerance (in bit/s).
18bff752 339@item -bufsize size
81d0618f 340Set rate control buffer size (in bits).
115329f1 341@item -vcodec codec
4c5f7207 342Force video codec to @var{codec}. Use the @code{copy} special value to
5ee03c86 343tell that the raw codec data must be copied as is.
18bff752 344@item -sameq
4c5f7207 345Use same video quality as source (implies VBR).
9181577c 346
115329f1 347@item -pass n
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348Select the pass number (1 or 2). It is useful to do two pass
349encoding. The statistics of the video are recorded in the first
350pass and the video is generated at the exact requested bitrate
351in the second pass.
9181577c 352
115329f1 353@item -passlogfile file
4c5f7207 354Set two pass logfile name to @var{file}.
9181577c 355
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356@item -newvideo
357Add a new video stream to the current output stream.
358
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359@end table
360
18bff752 361@section Advanced Video Options
9181577c 362
e99c4e10 363@table @option
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364@item -pix_fmt format
365Set pixel format.
115329f1 366@item -g gop_size
4c5f7207 367Set the group of pictures size.
115329f1 368@item -intra
4c5f7207 369Use only intra frames.
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370@item -vdt n
371Discard threshold.
115329f1 372@item -qscale q
4bef236b 373Use fixed video quantizer scale (VBR).
115329f1 374@item -qmin q
4bef236b 375minimum video quantizer scale (VBR)
115329f1 376@item -qmax q
4bef236b 377maximum video quantizer scale (VBR)
115329f1 378@item -qdiff q
4bef236b 379maximum difference between the quantizer scales (VBR)
115329f1 380@item -qblur blur
4bef236b 381video quantizer scale blur (VBR)
115329f1 382@item -qcomp compression
4bef236b 383video quantizer scale compression (VBR)
18bff752 384
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385@item -lmin lambda
386minimum video lagrange factor (VBR)
387@item -lmax lambda
388max video lagrange factor (VBR)
389@item -mblmin lambda
390minimum macroblock quantizer scale (VBR)
391@item -mblmax lambda
392maximum macroblock quantizer scale (VBR)
393
394These four options (lmin, lmax, mblmin, mblmax) use 'lambda' units,
395but you may use the QP2LAMBDA constant to easily convert from 'q' units:
396@example
397ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
398@end example
399
18bff752 400@item -rc_init_cplx complexity
4c5f7207 401initial complexity for single pass encoding
18bff752 402@item -b_qfactor factor
4c5f7207 403qp factor between P- and B-frames
18bff752 404@item -i_qfactor factor
4c5f7207 405qp factor between P- and I-frames
18bff752 406@item -b_qoffset offset
4c5f7207 407qp offset between P- and B-frames
18bff752 408@item -i_qoffset offset
4c5f7207 409qp offset between P- and I-frames
18bff752 410@item -rc_eq equation
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411Set rate control equation (@pxref{FFmpeg formula
412evaluator}) (default = @code{tex^qComp}).
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413@item -rc_override override
414rate control override for specific intervals
18bff752 415@item -me method
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416Set motion estimation method to @var{method}.
417Available methods are (from lowest to best quality):
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418@table @samp
419@item zero
5ee03c86 420Try just the (0, 0) vector.
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421@item phods
422@item log
423@item x1
424@item epzs
425(default method)
426@item full
427exhaustive search (slow and marginally better than epzs)
428@end table
429
430@item -dct_algo algo
4c5f7207 431Set DCT algorithm to @var{algo}. Available values are:
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432@table @samp
433@item 0
434FF_DCT_AUTO (default)
435@item 1
436FF_DCT_FASTINT
437@item 2
438FF_DCT_INT
439@item 3
440FF_DCT_MMX
441@item 4
442FF_DCT_MLIB
443@item 5
444FF_DCT_ALTIVEC
445@end table
446
447@item -idct_algo algo
4c5f7207 448Set IDCT algorithm to @var{algo}. Available values are:
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449@table @samp
450@item 0
451FF_IDCT_AUTO (default)
452@item 1
115329f1 453FF_IDCT_INT
18bff752 454@item 2
115329f1 455FF_IDCT_SIMPLE
18bff752 456@item 3
115329f1 457FF_IDCT_SIMPLEMMX
18bff752 458@item 4
115329f1 459FF_IDCT_LIBMPEG2MMX
18bff752 460@item 5
115329f1 461FF_IDCT_PS2
18bff752 462@item 6
115329f1 463FF_IDCT_MLIB
18bff752 464@item 7
115329f1 465FF_IDCT_ARM
18bff752 466@item 8
115329f1 467FF_IDCT_ALTIVEC
18bff752 468@item 9
115329f1 469FF_IDCT_SH4
18bff752 470@item 10
115329f1 471FF_IDCT_SIMPLEARM
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472@end table
473
474@item -er n
4c5f7207 475Set error resilience to @var{n}.
18bff752 476@table @samp
115329f1 477@item 1
1471c6c2 478FF_ER_CAREFUL (default)
18bff752 479@item 2
5ee03c86 480FF_ER_COMPLIANT
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481@item 3
482FF_ER_AGGRESSIVE
483@item 4
484FF_ER_VERY_AGGRESSIVE
485@end table
486
5ee03c86 487@item -ec bit_mask
4c5f7207 488Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of
5ee03c86 489the following values:
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490@table @samp
491@item 1
4c5f7207 492FF_EC_GUESS_MVS (default = enabled)
18bff752 493@item 2
4c5f7207 494FF_EC_DEBLOCK (default = enabled)
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495@end table
496
497@item -bf frames
4c5f7207 498Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4).
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499@item -mbd mode
500macroblock decision
501@table @samp
502@item 0
4c5f7207 503FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in FFmpeg).
18bff752 504@item 1
4c5f7207 505FF_MB_DECISION_BITS: Choose the one which needs the fewest bits.
18bff752 506@item 2
019c8838 507FF_MB_DECISION_RD: rate distortion
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508@end table
509
510@item -4mv
4c5f7207 511Use four motion vector by macroblock (MPEG-4 only).
18bff752 512@item -part
4c5f7207 513Use data partitioning (MPEG-4 only).
18bff752 514@item -bug param
4c5f7207 515Work around encoder bugs that are not auto-detected.
18bff752 516@item -strict strictness
4c5f7207 517How strictly to follow the standards.
5ee03c86 518@item -aic
4c5f7207 519Enable Advanced intra coding (h263+).
5ee03c86 520@item -umv
4c5f7207 521Enable Unlimited Motion Vector (h263+)
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522
523@item -deinterlace
4c5f7207 524Deinterlace pictures.
3841e813 525@item -ilme
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526Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
527Use this option if your input file is interlaced and you want
528to keep the interlaced format for minimum losses.
529The alternative is to deinterlace the input stream with
530@option{-deinterlace}, but deinterlacing introduces losses.
18bff752 531@item -psnr
4c5f7207 532Calculate PSNR of compressed frames.
18bff752 533@item -vstats
4c5f7207 534Dump video coding statistics to @file{vstats_HHMMSS.log}.
18bff752 535@item -vhook module
4c5f7207 536Insert video processing @var{module}. @var{module} contains the module
18bff752 537name and its parameters separated by spaces.
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538@item -top n
539top=1/bottom=0/auto=-1 field first
540@item -dc precision
541Intra_dc_precision.
542@item -vtag fourcc/tag
543Force video tag/fourcc.
544@item -qphist
545Show QP histogram.
546@item -vbsf bitstream filter
547Bitstream filters available are "dump_extra", "remove_extra", "noise".
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548@end table
549
550@section Audio Options
551
552@table @option
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553@item -aframes number
554Set the number of audio frames to record.
115329f1 555@item -ar freq
4c5f7207 556Set the audio sampling frequency (default = 44100 Hz).
115329f1 557@item -ab bitrate
4c5f7207 558Set the audio bitrate in kbit/s (default = 64).
18bff752 559@item -ac channels
4c5f7207 560Set the number of audio channels (default = 1).
5ee03c86 561@item -an
4c5f7207 562Disable audio recording.
5ee03c86 563@item -acodec codec
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564Force audio codec to @var{codec}. Use the @code{copy} special value to
565specify that the raw codec data must be copied as is.
de62a89d 566@item -newaudio
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567Add a new audio track to the output file. If you want to specify parameters,
568do so before @code{-newaudio} (@code{-acodec}, @code{-ab}, etc..).
de62a89d 569
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570Mapping will be done automatically, if the number of output streams is equal to
571the number of input streams, else it will pick the first one that matches. You
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572can override the mapping using @code{-map} as usual.
573
574Example:
575@example
576ffmpeg -i file.mpg -vcodec copy -acodec ac3 -ab 384 test.mpg -acodec mp2 -ab 192 -newaudio
577@end example
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578@item -alang code
579Set the ISO 639 language code (3 letters) of the current audio stream.
580@end table
581
582@section Advanced Audio options:
583
584@table @option
585@item -atag fourcc/tag
586Force audio tag/fourcc.
587@item -absf bitstream filter
588Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp".
589@end table
590
591@section Subtitle options:
592
593@table @option
594@item -scodec codec
595Force subtitle codec ('copy' to copy stream).
596@item -newsubtitle
597Add a new subtitle stream to the current output stream.
598@item -slang code
599Set the ISO 639 language code (3 letters) of the current subtitle stream.
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600@end table
601
602@section Audio/Video grab options
603
604@table @option
605@item -vd device
4c5f7207 606sEt video grab device (e.g. @file{/dev/video0}).
18bff752 607@item -vc channel
4c5f7207 608Set video grab channel (DV1394 only).
18bff752 609@item -tvstd standard
4c5f7207 610Set television standard (NTSC, PAL (SECAM)).
18bff752 611@item -dv1394
4c5f7207 612Set DV1394 grab.
18bff752 613@item -ad device
4c5f7207 614Set audio device (e.g. @file{/dev/dsp}).
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615@item -grab format
616Request grabbing using.
617@item -gd device
618Set grab device.
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619@end table
620
621@section Advanced options
622
623@table @option
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624@item -map input stream id[:input stream id]
625Set stream mapping from input streams to output streams.
626Just enumerate the input streams in the order you want them in the output.
627[input stream id] sets the (input) stream to sync against.
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628@item -map_meta_data outfile:infile
629Set meta data information of outfile from infile.
18bff752 630@item -debug
4c5f7207 631Print specific debug info.
115329f1 632@item -benchmark
4c5f7207 633Add timings for benchmarking.
4386f941 634@item -dump
4c5f7207 635Dump each input packet.
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636@item -hex
637When dumping packets, also dump the payload.
18bff752 638@item -bitexact
4c5f7207 639Only use bit exact algorithms (for codec testing).
18bff752 640@item -ps size
4c5f7207 641Set packet size in bits.
5ee03c86 642@item -re
4c5f7207 643Read input at native frame rate. Mainly used to simulate a grab device.
4386f941 644@item -loop_input
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645Loop over the input stream. Currently it works only for image
646streams. This option is used for automatic FFserver testing.
8108551a 647@item -loop_output number_of_times
019c8838 648Repeatedly loop output for formats that support looping such as animated GIF
4c5f7207 649(0 will loop the output infinitely).
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650@item -threads count
651Thread count.
c52e13f1 652@item -vsync parameter
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653Video sync method. Video will be stretched/squeezed to match the timestamps,
654it is done by duplicating and dropping frames. With -map you can select from
655which stream the timestamps should be taken. You can leave either video or
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656audio unchanged and sync the remaining stream(s) to the unchanged one.
657@item -async samples_per_second
29c9183c 658Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
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659the parameter is the maximum samples per second by which the audio is changed.
660-async 1 is a special case where only the start of the audio stream is corrected
661without any later correction.
9181577c 662@end table
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663
664@node FFmpeg formula evaluator
665@section FFmpeg formula evaluator
666
667When evaluating a rate control string, FFmpeg uses an internal formula
115329f1 668evaluator.
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669
670The following binary operators are available: @code{+}, @code{-},
671@code{*}, @code{/}, @code{^}.
672
673The following unary operators are available: @code{+}, @code{-},
674@code{(...)}.
675
676The following functions are available:
677@table @var
678@item sinh(x)
679@item cosh(x)
680@item tanh(x)
681@item sin(x)
682@item cos(x)
683@item tan(x)
684@item exp(x)
685@item log(x)
686@item squish(x)
687@item gauss(x)
688@item abs(x)
689@item max(x, y)
690@item min(x, y)
691@item gt(x, y)
692@item lt(x, y)
693@item eq(x, y)
694@item bits2qp(bits)
695@item qp2bits(qp)
696@end table
697
698The following constants are available:
699@table @var
700@item PI
701@item E
702@item iTex
703@item pTex
704@item tex
705@item mv
706@item fCode
707@item iCount
708@item mcVar
709@item var
710@item isI
711@item isP
712@item isB
713@item avgQP
714@item qComp
715@item avgIITex
716@item avgPITex
717@item avgPPTex
718@item avgBPTex
719@item avgTex
720@end table
721
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722@c man end
723
724@ignore
725
726@setfilename ffmpeg
727@settitle FFmpeg video converter
728
729@c man begin SEEALSO
019c8838 730ffserver(1), ffplay(1) and the HTML documentation of @file{ffmpeg}.
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731@c man end
732
733@c man begin AUTHOR
734Fabrice Bellard
735@c man end
736
737@end ignore
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738
739@section Protocols
740
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741The filename can be @file{-} to read from standard input or to write
742to standard output.
9181577c 743
4c5f7207 744FFmpeg also handles many protocols specified with an URL syntax.
9181577c 745
4c5f7207 746Use 'ffmpeg -formats' to see a list of the supported protocols.
9181577c 747
e99c4e10 748The protocol @code{http:} is currently used only to communicate with
4c5f7207 749FFserver (see the FFserver documentation). When FFmpeg will be a
e99c4e10 750video player it will also be used for streaming :-)
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751
752@chapter Tips
753
754@itemize
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755@item For streaming at very low bitrate application, use a low frame rate
756and a small GOP size. This is especially true for RealVideo where
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757the Linux player does not seem to be very fast, so it can miss
758frames. An example is:
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759
760@example
3c0ba870 761ffmpeg -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
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762@end example
763
764@item The parameter 'q' which is displayed while encoding is the current
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765quantizer. The value 1 indicates that a very good quality could
766be achieved. The value 31 indicates the worst quality. If q=31 appears
e99c4e10 767too often, it means that the encoder cannot compress enough to meet
4c5f7207 768your bitrate. You must either increase the bitrate, decrease the
e99c4e10 769frame rate or decrease the frame size.
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770
771@item If your computer is not fast enough, you can speed up the
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772compression at the expense of the compression ratio. You can use
773'-me zero' to speed up motion estimation, and '-intra' to disable
4c5f7207 774motion estimation completely (you have only I-frames, which means it
e99c4e10 775is about as good as JPEG compression).
9181577c 776
4c5f7207 777@item To have very low audio bitrates, reduce the sampling frequency
019c8838 778(down to 22050 kHz for MPEG audio, 22050 or 11025 for AC3).
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779
780@item To have a constant quality (but a variable bitrate), use the option
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781'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
782quality).
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783
784@item When converting video files, you can use the '-sameq' option which
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785uses the same quality factor in the encoder as in the decoder.
786It allows almost lossless encoding.
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787
788@end itemize
789
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790
791@chapter external libraries
792
793FFmpeg can be hooked up with a number of external libraries to add support
794for more formats.
795
796@section AMR
797
798AMR comes in two different flavors, WB and NB. FFmpeg can make use of the
799AMR WB (floating-point mode) and the AMR NB (both floating-point and
800fixed-point mode) reference decoders and encoders.
801
802@itemize
803
804@item For AMR WB floating-point download TS26.204 V5.1.0 from
805@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.204/26204-510.zip}
806and extract the source to @file{libavcodec/amrwb_float/}.
807
808@item For AMR NB floating-point download TS26.104 REL-5 V5.1.0 from
809@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.104/26104-510.zip}
810and extract the source to @file{libavcodec/amr_float/}.
811If you try this on Alpha, you may need to change @code{Word32} to
812@code{int} in @file{amr/typedef.h}.
813
814@item For AMR NB fixed-point download TS26.073 REL-5 V5.1.0 from
815@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.073/26073-510.zip}
816and extract the source to @file{libavcodec/amr}.
817You must also add @code{-DMMS_IO} and remove @code{-pedantic-errors}
818to/from @code{CFLAGS} in @file{libavcodec/amr/makefile}, i.e.
819``@code{CFLAGS = -Wall -I. \$(CFLAGS_\$(MODE)) -D\$(VAD) -DMMS_IO}''.
820
821@end itemize
822
823
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824@chapter Supported File Formats and Codecs
825
826You can use the @code{-formats} option to have an exhaustive list.
827
828@section File Formats
829
6bf40f39 830FFmpeg supports the following file formats through the @code{libavformat}
0699d2fe 831library:
9181577c 832
3fc9e78f 833@multitable @columnfractions .4 .1 .1 .4
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834@item Supported File Format @tab Encoding @tab Decoding @tab Comments
835@item MPEG audio @tab X @tab X
4c5f7207 836@item MPEG-1 systems @tab X @tab X
9181577c 837@tab muxed audio and video
4c5f7207 838@item MPEG-2 PS @tab X @tab X
9181577c 839@tab also known as @code{VOB} file
4c5f7207 840@item MPEG-2 TS @tab @tab X
9181577c 841@tab also known as DVB Transport Stream
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842@item ASF@tab X @tab X
843@item AVI@tab X @tab X
844@item WAV@tab X @tab X
9181577c 845@item Macromedia Flash@tab X @tab X
4c5f7207 846@tab Only embedded audio is decoded.
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847@item FLV @tab X @tab X
848@tab Macromedia Flash video files
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849@item Real Audio and Video @tab X @tab X
850@item Raw AC3 @tab X @tab X
851@item Raw MJPEG @tab X @tab X
852@item Raw MPEG video @tab X @tab X
853@item Raw PCM8/16 bits, mulaw/Alaw@tab X @tab X
854@item Raw CRI ADX audio @tab X @tab X
855@item Raw Shorten audio @tab @tab X
856@item SUN AU format @tab X @tab X
7fe4c823 857@item NUT @tab X @tab X @tab NUT Open Container Format
115329f1 858@item QuickTime @tab X @tab X
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859@item MPEG-4 @tab X @tab X
860@tab MPEG-4 is a variant of QuickTime.
115329f1 861@item Raw MPEG4 video @tab X @tab X
4fa1c4fa 862@item DV @tab X @tab X
701b603d 863@item 4xm @tab @tab X
4c5f7207 864@tab 4X Technologies format, used in some games.
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865@item Playstation STR @tab @tab X
866@item Id RoQ @tab @tab X
4c5f7207 867@tab Used in Quake III, Jedi Knight 2, other computer games.
4d3b1f8d 868@item Interplay MVE @tab @tab X
4c5f7207 869@tab Format used in various Interplay computer games.
b17e9c99 870@item WC3 Movie @tab @tab X
4c5f7207 871@tab Multimedia format used in Origin's Wing Commander III computer game.
2fdf638b 872@item Sega FILM/CPK @tab @tab X
4c5f7207 873@tab Used in many Sega Saturn console games.
2fdf638b 874@item Westwood Studios VQA/AUD @tab @tab X
4c5f7207 875@tab Multimedia formats used in Westwood Studios games.
4120a53a 876@item Id Cinematic (.cin) @tab @tab X
4c5f7207 877@tab Used in Quake II.
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878@item FLIC format @tab @tab X
879@tab .fli/.flc files
da00f30e 880@item Sierra VMD @tab @tab X
4c5f7207 881@tab Used in Sierra CD-ROM games.
d08d7142 882@item Sierra Online @tab @tab X
4c5f7207 883@tab .sol files used in Sierra Online games.
38088adf 884@item Matroska @tab @tab X
ad81a9fe 885@item Electronic Arts Multimedia @tab @tab X
4c5f7207 886@tab Used in various EA games; files have extensions like WVE and UV2.
353147ed 887@item Nullsoft Video (NSV) format @tab @tab X
4accd1fd 888@item ADTS AAC audio @tab X @tab X
ea395e8c 889@item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro.
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890@item American Laser Games MM @tab @tab X
891@tab Multimedia format used in games like Mad Dog McCree
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892@item AVS @tab @tab X
893@tab Multimedia format used by the Creature Shock game.
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894@item Smacker @tab @tab X
895@tab Multimedia format used by many games.
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896@item GXF @tab X @tab X
897@tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.
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898@item CIN @tab @tab X
899@tab Multimedia format used by Delphine Software games.
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900@item MXF @tab @tab X
901@tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
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902@item SEQ @tab @tab X
903@tab Tiertex .seq files used in the DOS CDROM version of the game Flashback.
353147ed 904@end multitable
9181577c 905
4c5f7207 906@code{X} means that encoding (resp. decoding) is supported.
9181577c 907
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908@section Image Formats
909
910FFmpeg can read and write images for each frame of a video sequence. The
911following image formats are supported:
912
3fc9e78f 913@multitable @columnfractions .4 .1 .1 .4
0699d2fe 914@item Supported Image Format @tab Encoding @tab Decoding @tab Comments
115329f1 915@item PGM, PPM @tab X @tab X
4c5f7207 916@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
2eb5d024 917@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
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918@item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
919@item .Y.U.V @tab X @tab X @tab one raw file per component
920@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
921@item PNG @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
3689cf16 922@item Targa @tab @tab X @tab Targa (.TGA) image format.
a991b1fe 923@item TIFF @tab @tab X @tab Only 24 bit/pixel images are supported.
6a91ec51 924@item SGI @tab X @tab X @tab SGI RGB image format
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925@end multitable
926
4c5f7207 927@code{X} means that encoding (resp. decoding) is supported.
0699d2fe 928
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929@section Video Codecs
930
3fc9e78f 931@multitable @columnfractions .4 .1 .1 .4
9181577c 932@item Supported Codec @tab Encoding @tab Decoding @tab Comments
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933@item MPEG-1 video @tab X @tab X
934@item MPEG-2 video @tab X @tab X
2bc5da7b 935@item MPEG-4 @tab X @tab X
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936@item MSMPEG4 V1 @tab X @tab X
937@item MSMPEG4 V2 @tab X @tab X
2bc5da7b 938@item MSMPEG4 V3 @tab X @tab X
9181577c 939@item WMV7 @tab X @tab X
4c5f7207 940@item WMV8 @tab X @tab X @tab not completely working
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941@item WMV9 @tab @tab X @tab not completely working
942@item VC1 @tab @tab X
b06b45c4 943@item H.261 @tab X @tab X
4c5f7207 944@item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0
b06b45c4 945@item H.264 @tab @tab X
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946@item RealVideo 1.0 @tab X @tab X
947@item RealVideo 2.0 @tab X @tab X
115329f1 948@item MJPEG @tab X @tab X
4c5f7207 949@item lossless MJPEG @tab X @tab X
26d6d032 950@item JPEG-LS @tab X @tab X @tab fourcc: MJLS, lossless and near-lossless is supported
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951@item Apple MJPEG-B @tab @tab X
952@item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X
115329f1 953@item DV @tab X @tab X
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954@item HuffYUV @tab X @tab X
955@item FFmpeg Video 1 @tab X @tab X @tab experimental lossless codec (fourcc: FFV1)
956@item FFmpeg Snow @tab X @tab X @tab experimental wavelet codec (fourcc: SNOW)
701b603d 957@item Asus v1 @tab X @tab X @tab fourcc: ASV1
4d3b1f8d 958@item Asus v2 @tab X @tab X @tab fourcc: ASV2
701b603d 959@item Creative YUV @tab @tab X @tab fourcc: CYUV
d2bfadc0 960@item Sorenson Video 1 @tab X @tab X @tab fourcc: SVQ1
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961@item Sorenson Video 3 @tab @tab X @tab fourcc: SVQ3
962@item On2 VP3 @tab @tab X @tab still experimental
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963@item On2 VP5 @tab @tab X @tab fourcc: VP50
964@item On2 VP6 @tab @tab X @tab fourcc: VP62
d6896c49 965@item Theora @tab @tab X @tab still experimental
cdb2c1ca 966@item Intel Indeo 3 @tab @tab X
9303d49c 967@item FLV @tab X @tab X @tab Sorenson H.263 used in Flash
0919e788 968@item Flash Screen Video @tab @tab X @tab fourcc: FSV1
4d3b1f8d 969@item ATI VCR1 @tab @tab X @tab fourcc: VCR1
7fe4c823 970@item ATI VCR2 @tab @tab X @tab fourcc: VCR2
4d3b1f8d 971@item Cirrus Logic AccuPak @tab @tab X @tab fourcc: CLJR
4c5f7207 972@item 4X Video @tab @tab X @tab Used in certain computer games.
115329f1 973@item Sony Playstation MDEC @tab @tab X
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974@item Id RoQ @tab @tab X @tab Used in Quake III, Jedi Knight 2, other computer games.
975@item Xan/WC3 @tab @tab X @tab Used in Wing Commander III .MVE files.
976@item Interplay Video @tab @tab X @tab Used in Interplay .MVE files.
070ed1bc 977@item Apple Animation @tab @tab X @tab fourcc: 'rle '
42cad81a 978@item Apple Graphics @tab @tab X @tab fourcc: 'smc '
2fdf638b 979@item Apple Video @tab @tab X @tab fourcc: rpza
d08d7142 980@item Apple QuickDraw @tab @tab X @tab fourcc: qdrw
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981@item Cinepak @tab @tab X
982@item Microsoft RLE @tab @tab X
983@item Microsoft Video-1 @tab @tab X
4120a53a 984@item Westwood VQA @tab @tab X
4c5f7207 985@item Id Cinematic Video @tab @tab X @tab Used in Quake II.
1dc1ed99 986@item Planar RGB @tab @tab X @tab fourcc: 8BPS
42cad81a 987@item FLIC video @tab @tab X
9a4117d5 988@item Duck TrueMotion v1 @tab @tab X @tab fourcc: DUCK
dce76c20 989@item Duck TrueMotion v2 @tab @tab X @tab fourcc: TM20
4c5f7207 990@item VMD Video @tab @tab X @tab Used in Sierra VMD files.
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991@item MSZH @tab @tab X @tab Part of LCL
992@item ZLIB @tab X @tab X @tab Part of LCL, encoder experimental
9d53d58e 993@item TechSmith Camtasia @tab @tab X @tab fourcc: TSCC
d0a0bbd2 994@item IBM Ultimotion @tab @tab X @tab fourcc: ULTI
ab711b3c 995@item Miro VideoXL @tab @tab X @tab fourcc: VIXL
acfd8f0f 996@item QPEG @tab @tab X @tab fourccs: QPEG, Q1.0, Q1.1
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997@item LOCO @tab @tab X @tab
998@item Winnov WNV1 @tab @tab X @tab
589f8220 999@item Autodesk Animator Studio Codec @tab @tab X @tab fourcc: AASC
115329f1 1000@item Fraps FPS1 @tab @tab X @tab
2b6c1d80 1001@item CamStudio @tab @tab X @tab fourcc: CSCD
4e114829 1002@item American Laser Games Video @tab @tab X @tab Used in games like Mad Dog McCree
f48d6e1b 1003@item ZMBV @tab X @tab X @tab Encoder works only on PAL8
26376701 1004@item AVS Video @tab @tab X @tab Video encoding used by the Creature Shock game.
348efc18 1005@item Smacker Video @tab @tab X @tab Video encoding used in Smacker.
dfca23e3 1006@item RTjpeg @tab @tab X @tab Video encoding used in NuppelVideo files.
fd7b1991 1007@item KMVC @tab @tab X @tab Codec used in Worms games.
eb57c889 1008@item VMware Video @tab @tab X @tab Codec used in videos captured by VMware.
dc56e0de 1009@item Cin Video @tab @tab X @tab Codec used in Delphine Software games.
29f86228 1010@item Tiertex Seq Video @tab @tab X @tab Codec used in DOS CDROM FlashBack game.
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1011@end multitable
1012
4c5f7207 1013@code{X} means that encoding (resp. decoding) is supported.
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1014
1015@section Audio Codecs
1016
1017@multitable @columnfractions .4 .1 .1 .1 .7
1018@item Supported Codec @tab Encoding @tab Decoding @tab Comments
115329f1 1019@item MPEG audio layer 2 @tab IX @tab IX
9181577c 1020@item MPEG audio layer 1/3 @tab IX @tab IX
4c5f7207 1021@tab MP3 encoding is supported through the external library LAME.
37776c3b 1022@item AC3 @tab IX @tab IX
4c5f7207 1023@tab liba52 is used internally for decoding.
34d7008d 1024@item Vorbis @tab X @tab X
4745b5bf 1025@item WMA V1/V2 @tab @tab X
f6fa7a6c 1026@item AAC @tab X @tab X
4c5f7207 1027@tab Supported through the external library libfaac/libfaad.
d4c3c5a6 1028@item Microsoft ADPCM @tab X @tab X
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1029@item MS IMA ADPCM @tab X @tab X
1030@item QT IMA ADPCM @tab @tab X
1031@item 4X IMA ADPCM @tab @tab X
d4e437df 1032@item G.726 ADPCM @tab X @tab X
b17e9c99 1033@item Duck DK3 IMA ADPCM @tab @tab X
4c5f7207 1034@tab Used in some Sega Saturn console games.
b17e9c99 1035@item Duck DK4 IMA ADPCM @tab @tab X
4c5f7207 1036@tab Used in some Sega Saturn console games.
2fdf638b 1037@item Westwood Studios IMA ADPCM @tab @tab X
4c5f7207 1038@tab Used in Westwood Studios games like Command and Conquer.
7d8379f2 1039@item SMJPEG IMA ADPCM @tab @tab X
4c5f7207 1040@tab Used in certain Loki game ports.
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1041@item CD-ROM XA ADPCM @tab @tab X
1042@item CRI ADX ADPCM @tab X @tab X
4c5f7207 1043@tab Used in Sega Dreamcast games.
7d8379f2 1044@item Electronic Arts ADPCM @tab @tab X
4c5f7207 1045@tab Used in various EA titles.
b3bfb299 1046@item Creative ADPCM @tab @tab X
2433f24f 1047@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
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1048@item RA144 @tab @tab X
1049@tab Real 14400 bit/s codec
1050@item RA288 @tab @tab X
1051@tab Real 28800 bit/s codec
37776c3b 1052@item RADnet @tab X @tab IX
4c5f7207 1053@tab Real low bitrate AC3 codec, liba52 is used for decoding.
2eb5d024 1054@item AMR-NB @tab X @tab X
4c5f7207 1055@tab Supported through an external library.
d663a1fd 1056@item AMR-WB @tab X @tab X
4c5f7207 1057@tab Supported through an external library.
2eb5d024 1058@item DV audio @tab @tab X
4d3b1f8d 1059@item Id RoQ DPCM @tab @tab X
4c5f7207 1060@tab Used in Quake III, Jedi Knight 2, other computer games.
4d3b1f8d 1061@item Interplay MVE DPCM @tab @tab X
4c5f7207 1062@tab Used in various Interplay computer games.
b17e9c99 1063@item Xan DPCM @tab @tab X
4c5f7207 1064@tab Used in Origin's Wing Commander IV AVI files.
d08d7142 1065@item Sierra Online DPCM @tab @tab X
4c5f7207 1066@tab Used in Sierra Online game audio files.
d6896c49
AB
1067@item Apple MACE 3 @tab @tab X
1068@item Apple MACE 6 @tab @tab X
13dfd2b9
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1069@item FLAC lossless audio @tab @tab X
1070@item Shorten lossless audio @tab @tab X
f770ee03
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1071@item Apple lossless audio @tab @tab X
1072@tab QuickTime fourcc 'alac'
33a4d8b1 1073@item FFmpeg Sonic @tab X @tab X
4c5f7207 1074@tab experimental lossy/lossless codec
d9b1c197
RT
1075@item Qdesign QDM2 @tab @tab X
1076@tab there are still some distortions
440e7988
RT
1077@item Real COOK @tab @tab X
1078@tab All versions except 5.1 are supported
e839a994 1079@item DSP Group TrueSpeech @tab @tab X
3dc411c0 1080@item True Audio (TTA) @tab @tab X
348efc18 1081@item Smacker Audio @tab @tab X
730581f3 1082@item WavPack Audio @tab @tab X
dc56e0de
BC
1083@item Cin Audio @tab @tab X
1084@tab Codec used in Delphine Software games.
84ed36da 1085@item Intel Music Coder @tab @tab X
9181577c
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1086@end multitable
1087
4c5f7207 1088@code{X} means that encoding (resp. decoding) is supported.
9181577c 1089
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1090@code{I} means that an integer-only version is available, too (ensures high
1091performance on systems without hardware floating point support).
9181577c 1092
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1093@chapter Platform Specific information
1094
1095@section Linux
1096
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1097FFmpeg should be compiled with at least GCC 2.95.3. GCC 3.2 is the
1098preferred compiler now for FFmpeg. All future optimizations will depend on
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1099features only found in GCC 3.2.
1100
1101@section BSD
1102
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1103BSD make will not build FFmpeg, you need to install and use GNU Make
1104(@file{gmake}).
1105
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1106@section Windows
1107
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1108@subsection Native Windows compilation
1109
1110@itemize
1111@item Install the current versions of MSYS and MinGW from
1112@url{http://www.mingw.org/}. You can find detailed installation
1113instructions in the download section and the FAQ.
1114
4c5f7207 1115@item If you want to test the FFplay, also download
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1116the MinGW development library of SDL 1.2.x
1117(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
4c5f7207 1118@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
50f52fcd 1119unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
988a9f9e
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1120directory. Edit the @file{sdl-config} script so that it gives the
1121correct SDL directory when invoked.
50f52fcd 1122
e926e391 1123@item Extract the current version of FFmpeg.
115329f1 1124
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1125@item Start the MSYS shell (file @file{msys.bat}).
1126
4c5f7207
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1127@item Change to the FFmpeg directory and follow
1128 the instructions of how to compile FFmpeg (file
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1129@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
1130suffices. If you have problems using SDL, verify that
1131@file{sdl-config} can be launched from the MSYS command line.
1132
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DB
1133@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
1134@file{make install}. Don't forget to copy @file{SDL.dll} to the place
1135you launch @file{ffplay} from.
50f52fcd 1136
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1137@end itemize
1138
115329f1 1139Notes:
988a9f9e 1140@itemize
50f52fcd 1141
988a9f9e
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1142@item The target @file{make wininstaller} can be used to create a
1143Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
4c5f7207 1144must be copied to the FFmpeg directory in order to build the
988a9f9e
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1145installer.
1146
4c5f7207 1147@item By using @code{./configure --enable-shared} when configuring FFmpeg,
988a9f9e
FB
1148you can build @file{avcodec.dll} and @file{avformat.dll}. With
1149@code{make install} you install the FFmpeg DLLs and the associated
115329f1 1150headers in @file{Program Files/FFmpeg}.
988a9f9e 1151
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1152@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
1153when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
988a9f9e 1154C++ @code{lib} tool to build @code{avcodec.lib} and
4c5f7207 1155@code{avformat.lib}. With these libraries you can link your Visual C++
be0efc0c 1156code directly with the FFmpeg DLLs (see below).
988a9f9e
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1157
1158@end itemize
b030b284 1159
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MB
1160@subsection Visual C++ compatibility
1161
1162FFmpeg will not compile under Visual C++ -- and it has too many
1163dependencies on the GCC compiler to make a port viable. However,
1164if you want to use the FFmpeg libraries in your own applications,
1165you can still compile those applications using Visual C++. An
1166important restriction to this is that you have to use the
1167dynamically linked versions of the FFmpeg libraries (i.e. the
1168DLLs), and you have to make sure that Visual-C++-compatible
1169import libraries are created during the FFmpeg build process.
1170
1171This description of how to use the FFmpeg libraries with Visual C++ is
1172based on Visual C++ 2005 Express Edition Beta 2. If you have a different
1173version, you might have to modify the procedures slightly.
1174
1175Here are the step-by-step instructions for building the FFmpeg libraries
1176so they can be used with Visual C++:
1177
1178@enumerate
1179
1180@item Install Visual C++ (if you haven't done so already).
1181
1182@item Install MinGW and MSYS as described above.
1183
1184@item Add a call to @file{vcvars32.bat} (which sets up the environment
1185variables for the Visual C++ tools) as the first line of
1186@file{msys.bat}. The standard location for @file{vcvars32.bat} is
1187@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
1188and the standard location for @file{msys.bat} is
1189@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
1190following line as the first line of @file{msys.bat}:
1191
1192@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
1193
1194@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
1195If you get a help message with the command line options of @code{link.exe},
1196this means your environment variables are set up correctly, the
1197Microsoft linker is on the path and will be used by FFmpeg to
1198create Visual-C++-compatible import libraries.
1199
e926e391 1200@item Extract the current version of FFmpeg and change to the FFmpeg directory.
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1201
1202@item Type the command
51d8321d
DB
1203@code{./configure --enable-shared --disable-static --enable-memalign-hack}
1204to configure and, if that didn't produce any errors,
1205type @code{make} to build FFmpeg.
be0efc0c
MB
1206
1207@item The subdirectories @file{libavformat}, @file{libavcodec}, and
1208@file{libavutil} should now contain the files @file{avformat.dll},
1209@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
1210@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
1211DLLs to your System32 directory (typically @file{C:\Windows\System32}).
1212
1213@end enumerate
1214
1215And here is how to use these libraries with Visual C++:
1216
1217@enumerate
1218
1219@item Create a new console application ("File / New / Project") and then
1220select "Win32 Console Application". On the appropriate page of the
1221Application Wizard, uncheck the "Precompiled headers" option.
1222
1223@item Write the source code for your application, or, for testing, just
1224copy the code from an existing sample application into the source file
1225that Visual C++ has already created for you. (Note that your source
1226filehas to have a @code{.cpp} extension; otherwise, Visual C++ won't
1227compile the FFmpeg headers correctly because in C mode, it doesn't
1228recognize the @code{inline} keyword.) For example, you can copy
1229@file{output_example.c} from the FFmpeg distribution (but you will
1230have to make minor modifications so the code will compile under
1231C++, see below).
1232
1233@item Open the "Project / Properties" dialog box. In the "Configuration"
1234combo box, select "All Configurations" so that the changes you make will
1235affect both debug and release builds. In the tree view on the left hand
1236side, select "C/C++ / General", then edit the "Additional Include
1237Directories" setting to contain the complete paths to the
1238@file{libavformat}, @file{libavcodec}, and @file{libavutil}
1239subdirectories of your FFmpeg directory. Note that the directories have
1240to be separated using semicolons. Now select "Linker / General" from the
1241tree view and edit the "Additional Library Directories" setting to
1242contain the same three directories.
1243
1244@item Still in the "Project / Properties" dialog box, select "Linker / Input"
1245from the tree view, then add the files @file{avformat.lib},
1246@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
1247Dependencies". Note that the names of the libraries have to be separated
1248using spaces.
1249
765c3440 1250@item Now, select "C/C++ / Code Generation" from the tree view. Select
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MB
1251"Debug" in the "Configuration" combo box. Make sure that "Runtime
1252Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
1253the "Configuration" combo box and make sure that "Runtime Library" is
1254set to "Multi-threaded DLL".
1255
1256@item Click "OK" to close the "Project / Properties" dialog box and build
1257the application. Hopefully, it should compile and run cleanly. If you
1258used @file{output_example.c} as your sample application, you will get a
1259few compiler errors, but they are easy to fix. The first type of error
1260occurs because Visual C++ doesn't allow an @code{int} to be converted to
1261an @code{enum} without a cast. To solve the problem, insert the required
1262casts (this error occurs once for a @code{CodecID} and once for a
1263@code{CodecType}). The second type of error occurs because C++ requires
1264the return value of @code{malloc} to be cast to the exact type of the
1265pointer it is being assigned to. Visual C++ will complain that, for
1266example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
1267an explicit cast. So insert an explicit cast in these places to silence
1268the compiler. The third type of error occurs because the @code{snprintf}
1269library function is called @code{_snprintf} under Visual C++. So just
1270add an underscore to fix the problem. With these changes,
1271@file{output_example.c} should compile under Visual C++, and the
1272resulting executable should produce valid video files.
1273
1274@end enumerate
1275
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1276@subsection Cross compilation for Windows with Linux
1277
1278You must use the MinGW cross compilation tools available at
1279@url{http://www.mingw.org/}.
1280
4c5f7207 1281Then configure FFmpeg with the following options:
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FB
1282@example
1283./configure --enable-mingw32 --cross-prefix=i386-mingw32msvc-
1284@end example
019c8838 1285(you can change the cross-prefix according to the prefix chosen for the
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1286MinGW tools).
1287
4c5f7207 1288Then you can easily test FFmpeg with Wine
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1289(@url{http://www.winehq.com/}).
1290
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DB
1291@subsection Compilation under Cygwin
1292
1293Cygwin works very much like Unix.
1294
1295Just install your Cygwin with all the "Base" packages, plus the
1296following "Devel" ones:
1297@example
1298binutils, gcc-core, make, subversion
1299@end example
1300
1301Do not install binutils-20060709-1 (they are buggy on shared builds);
1302use binutils-20050610-1 instead.
1303
1304Then run
1305
1306@example
1307./configure --enable-static --disable-shared
1308@end example
1309
1310to make a static build or
1311
1312@example
1313./configure --enable-shared --disable-static
1314@end example
1315
1316to build shared libraries.
1317
1318If you want to build FFmpeg with additional libraries, download Cygwin
1319"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
1320and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
1321(@url{http://cygwinports.dotsrc.org/}).
1322
1323@subsection Crosscompilation for Windows under Cygwin
1324
1325With Cygwin you can create Windows binaries that don't need the cygwin1.dll.
1326
1327Just install your Cygwin as explained before, plus these additional
1328"Devel" packages:
1329@example
1330gcc-mingw-core, mingw-runtime, mingw-zlib
1331@end example
1332
1333and add some special flags to your configure invocation.
1334
1335For a static build run
1336@example
1337./configure --enable-mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1338@end example
1339
1340and for a build with shared libraries
1341@example
1342./configure --enable-mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1343@end example
1344
47d944d2
FB
1345@section BeOS
1346
1347The configure script should guess the configuration itself.
1348Networking support is currently not finished.
1349errno issues fixed by Andrew Bachmann.
1350
1351Old stuff:
1352
7dd611c9 1353François Revol - revol at free dot fr - April 2002
47d944d2 1354
115329f1 1355The configure script should guess the configuration itself,
4c5f7207 1356however I still didn't test building on the net_server version of BeOS.
47d944d2 1357
4c5f7207 1358FFserver is broken (needs poll() implementation).
47d944d2 1359
4c5f7207 1360There are still issues with errno codes, which are negative in BeOS, and
115329f1 1361that FFmpeg negates when returning. This ends up turning errors into
47d944d2
FB
1362valid results, then crashes.
1363(To be fixed)
1364
34d7008d 1365@chapter Developers Guide
9181577c
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1366
1367@section API
a0b72f90 1368@itemize @bullet
9181577c 1369@item libavcodec is the library containing the codecs (both encoding and
4c5f7207 1370decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
9181577c 1371
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DB
1372@item libavformat is the library containing the file format handling (mux and
1373demux code for several formats). Look at @file{ffplay.c} to use it in a
a93b9dba
FB
1374player. See @file{output_example.c} to use it to generate audio or video
1375streams.
1376
9181577c
FB
1377@end itemize
1378
1379@section Integrating libavcodec or libavformat in your program
1380
1381You can integrate all the source code of the libraries to link them
1382statically to avoid any version problem. All you need is to provide a
1383'config.mak' and a 'config.h' in the parent directory. See the defines
1384generated by ./configure to understand what is needed.
1385
1386You can use libavcodec or libavformat in your commercial program, but
1387@emph{any patch you make must be published}. The best way to proceed is
4c5f7207 1388to send your patches to the FFmpeg mailing list.
9181577c 1389
80d1c272 1390@node Coding Rules
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1391@section Coding Rules
1392
4c5f7207 1393FFmpeg is programmed in the ISO C90 language with a few additional
cb6e87c1
FH
1394features from ISO C99, namely:
1395@itemize @bullet
1396@item
1397the @samp{inline} keyword;
1398@item
1399@samp{//} comments;
1400@item
1401designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
1402@item
114afa9c 1403compound literals (@samp{x = (struct s) @{ 17, 23 @};})
cb6e87c1
FH
1404@end itemize
1405
1406These features are supported by all compilers we care about, so we won't
1407accept patches to remove their use unless they absolutely don't impair
1408clarity and performance.
1409
4c5f7207 1410All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
cb6e87c1
FH
1411compiles with several other compilers, such as the Compaq ccc compiler
1412or Sun Studio 9, and we would like to keep it that way unless it would
1413be exceedingly involved. To ensure compatibility, please don't use any
4c5f7207 1414additional C99 features or GCC extensions. Especially watch out for:
cb6e87c1
FH
1415@itemize @bullet
1416@item
1417mixing statements and declarations;
1418@item
1419@samp{long long} (use @samp{int64_t} instead);
1420@item
1421@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
1422@item
019c8838 1423GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
cb6e87c1 1424@end itemize
9181577c 1425
53862e0f 1426Indent size is 4.
b86e38a0 1427The presentation is the one specified by 'indent -i4 -kr -nut'.
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DB
1428The TAB character is forbidden outside of Makefiles as is any
1429form of trailing whitespace. Commits containing either will be
1c1b5a40 1430rejected by the Subversion repository.
9181577c 1431
4c5f7207 1432Main priority in FFmpeg is simplicity and small code size (=less
9181577c
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1433bugs).
1434
4c5f7207
DB
1435Comments: Use the JavaDoc/Doxygen
1436format (see examples below) so that code documentation
1437can be generated automatically. All nontrivial functions should have a comment
1438above them explaining what the function does, even if it's just one sentence.
1439All structures and their member variables should be documented, too.
f4888b83
MN
1440@example
1441/**
2185824b
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1442 * @@file mpeg.c
1443 * MPEG codec.
1444 * @@author ...
1445 */
f4888b83
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1446
1447/**
2185824b
MR
1448 * Summary sentence.
1449 * more text ...
1450 * ...
1451 */
114afa9c 1452typedef struct Foobar@{
2185824b
MR
1453 int var1; /**< var1 description */
1454 int var2; ///< var2 description
1455 /** var3 description */
1456 int var3;
114afa9c 1457@} Foobar;
f4888b83
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1458
1459/**
2185824b
MR
1460 * Summary sentence.
1461 * more text ...
1462 * ...
1463 * @@param my_parameter description of my_parameter
1464 * @@return return value description
1465 */
f4888b83
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1466int myfunc(int my_parameter)
1467...
1468@end example
9181577c 1469
115329f1 1470fprintf and printf are forbidden in libavformat and libavcodec,
36d9b4e8
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1471please use av_log() instead.
1472
1c1b5a40 1473@section Development Policy
7a57b90c
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1474
1475@enumerate
115329f1 1476@item
7a57b90c 1477 You must not commit code which breaks FFmpeg! (Meaning unfinished but
4c5f7207 1478 enabled code which breaks compilation or compiles but does not work or
7a57b90c
MN
1479 breaks the regression tests)
1480 You can commit unfinished stuff (for testing etc), but it must be disabled
1481 (#ifdef etc) by default so it does not interfere with other developers'
1482 work.
115329f1 1483@item
7a57b90c 1484 You don't have to over-test things. If it works for you, and you think it
4c5f7207
DB
1485 should work for others, then commit. If your code has problems
1486 (portability, triggers compiler bugs, unusual environment etc) they will be
7a57b90c 1487 reported and eventually fixed.
115329f1 1488@item
7a57b90c
MN
1489 Do not commit unrelated changes together, split them into self-contained
1490 pieces.
1491@item
1492 Do not change behavior of the program (renaming options etc) without
019c8838 1493 first discussing it on the ffmpeg-devel mailing list. Do not remove
7a57b90c 1494 functionality from the code. Just improve!
115329f1 1495
4c5f7207 1496 Note: Redundant code can be removed.
7a57b90c
MN
1497@item
1498 Do not commit changes to the build system (Makefiles, configure script)
019c8838 1499 which change behavior, defaults etc, without asking first. The same
7a57b90c
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1500 applies to compiler warning fixes, trivial looking fixes and to code
1501 maintained by other developers. We usually have a reason for doing things
019c8838 1502 the way we do. Send your changes as patches to the ffmpeg-devel mailing
7a57b90c
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1503 list, and if the code maintainers say OK, you may commit. This does not
1504 apply to files you wrote and/or maintain.
1505@item
1506 We refuse source indentation and other cosmetic changes if they are mixed
1507 with functional changes, such commits will be rejected and removed. Every
1508 developer has his own indentation style, you should not change it. Of course
1509 if you (re)write something, you can use your own style, even though we would
4c5f7207
DB
1510 prefer if the indentation throughout FFmpeg was consistent (Many projects
1511 force a given indentation style - we don't.). If you really need to make
7a57b90c
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1512 indentation changes (try to avoid this), separate them strictly from real
1513 changes.
1514
114afa9c 1515 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
115329f1 1516 then either do NOT change the indentation of the inner part within (don't
019c8838 1517 move it to the right)! or do so in a separate commit
7a57b90c
MN
1518@item
1519 Always fill out the commit log message. Describe in a few lines what you
1520 changed and why. You can refer to mailing list postings if you fix a
1521 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1522@item
1523 If you apply a patch by someone else, include the name and email address in
1c1b5a40 1524 the log message. Since the ffmpeg-cvslog mailing list is publicly
019c8838
DB
1525 archived you should add some SPAM protection to the email address. Send an
1526 answer to ffmpeg-devel (or wherever you got the patch from) saying that
7a57b90c
MN
1527 you applied the patch.
1528@item
5ab0f204
DB
1529 Do NOT commit to code actively maintained by others without permission.
1530 Send a patch to ffmpeg-devel instead. If noone answers within a reasonable
1531 timeframe (12h for build failures and security fixes, 3 days small changes,
1532 1 week for big patches) then commit your patch if you think it's OK.
1533 Also note, the maintainer can simply ask for more time to review!
7a57b90c 1534@item
1c1b5a40 1535 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
7a57b90c
MN
1536 are sent there and reviewed by all the other developers. Bugs and possible
1537 improvements or general questions regarding commits are discussed there. We
1538 expect you to react if problems with your code are uncovered.
1539@item
1540 Update the documentation if you change behavior or add features. If you are
019c8838 1541 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
7a57b90c
MN
1542 maintainer(s) will review and commit your stuff.
1543@item
4c5f7207
DB
1544 Never write to unallocated memory, never write over the end of arrays,
1545 always check values read from some untrusted source before using them
1546 as array index or other risky things.
76bec1d8
AS
1547@item
1548 Remember to check if you need to bump versions for the specific libav
f0efbde7 1549 parts (libavutil, libavcodec, libavformat) you are changing. You need
76bec1d8
AS
1550 to change the version integer and the version string.
1551 Incrementing the first component means no backward compatibility to
a940b428 1552 previous versions (e.g. removal of a function from the public API).
76bec1d8 1553 Incrementing the second component means backward compatible change
a940b428 1554 (e.g. addition of a function to the public API).
76bec1d8
AS
1555 Incrementing the third component means a noteworthy binary compatible
1556 change (e.g. encoder bug fix that matters for the decoder).
ebd32fd7 1557@item
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1558 If you add a new codec, remember to update the changelog, add it to
1559 the supported codecs table in the documentation and bump the second
1560 component of the @file{libavcodec} version number appropriately. If
1561 it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
1562 is only a decoder.
114afa9c 1563@end enumerate
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1564
1565We think our rules are not too hard. If you have comments, contact us.
1566
1567Note, these rules are mostly borrowed from the MPlayer project.
1568
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1569@section Submitting patches
1570
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1571First, (@pxref{Coding Rules}) above if you didn't yet.
1572
6a6810b1 1573When you submit your patch, try to send a unified diff (diff '-up'
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1574option). I cannot read other diffs :-)
1575
6e5c1877 1576Also please do not submit patches which contain several unrelated changes.
115329f1 1577Split them into individual self-contained patches; this makes reviewing
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1578them much easier.
1579
9181577c 1580Run the regression tests before submitting a patch so that you can
6bf40f39 1581verify that there are no big problems.
9181577c 1582
9181577c 1583Patches should be posted as base64 encoded attachments (or any other
4c5f7207 1584encoding which ensures that the patch won't be trashed during
115329f1 1585transmission) to the ffmpeg-devel mailing list, see
2b165e29 1586@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
9181577c 1587
54fcf429 1588It also helps quite a bit if you tell us what the patch does (for example
4c5f7207 1589'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
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1590and has no lrint()')
1591
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1592We reply to all submitted patches and either apply or reject with some
1593explanation why, but sometimes we are quite busy so it can take a week or two.
cf7f2b16 1594
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1595@section Regression tests
1596
1c1b5a40 1597Before submitting a patch (or committing to the repository), you should at least
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1598test that you did not break anything.
1599
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1600The regression tests build a synthetic video stream and a synthetic
1601audio stream. These are then encoded and decoded with all codecs or
9181577c 1602formats. The CRC (or MD5) of each generated file is recorded in a
4c5f7207 1603result file. A 'diff' is launched to compare the reference results and
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1604the result file.
1605
4c5f7207 1606The regression tests then go on to test the FFserver code with a
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1607limited set of streams. It is important that this step runs correctly
1608as well.
1609
36d9b4e8 1610Run 'make test' to test all the codecs and formats.
9181577c 1611
4c5f7207 1612Run 'make fulltest' to test all the codecs, formats and FFserver.
9181577c 1613
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1614[Of course, some patches may change the results of the regression tests. In
1615this case, the reference results of the regression tests shall be modified
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1616accordingly].
1617
1618@bye