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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 grab video and audio from devices given that you specify the input
30format and device.
e99c4e10 31
9181577c 32@example
cc58300e 33ffmpeg -f audio_device -i /dev/dsp -f video4linux2 -i /dev/video0 /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
913e4081 44FFmpeg can grab the X11 display.
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45
46@example
9e0ab666 47ffmpeg -f x11grab -s cif -i :0.0 /tmp/out.mpg
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48@end example
49
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500.0 is display.screen number of your X11 server, same as
51the DISPLAY environment variable.
76d2efda 52
0cd4faf9 53@example
9e0ab666 54ffmpeg -f x11grab -s cif -i :0.0+10,20 /tmp/out.mpg
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55@end example
56
570.0 is display.screen number of your X11 server, same as the DISPLAY environment
58variable. 10 is the x-offset and 20 the y-offset for the grabbing.
59
6bf40f39 60@section Video and Audio file format conversion
9181577c 61
4c5f7207 62* FFmpeg can use any supported file format and protocol as input:
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63
64Examples:
65
4c5f7207 66* You can use YUV files as input:
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67
68@example
115329f1 69ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
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70@end example
71
115329f1 72It will use the files:
9181577c 73@example
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74/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
75/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
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76@end example
77
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78The Y files use twice the resolution of the U and V files. They are
79raw files, without header. They can be generated by all decent video
80decoders. You must specify the size of the image with the @option{-s} option
4c5f7207 81if FFmpeg cannot guess it.
9181577c 82
4c5f7207 83* You can input from a raw YUV420P file:
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84
85@example
e99c4e10 86ffmpeg -i /tmp/test.yuv /tmp/out.avi
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87@end example
88
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89test.yuv is a file containing raw YUV planar data. Each frame is composed
90of the Y plane followed by the U and V planes at half vertical and
e99c4e10 91horizontal resolution.
9181577c 92
4c5f7207 93* You can output to a raw YUV420P file:
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94
95@example
f926cbe7 96ffmpeg -i mydivx.avi hugefile.yuv
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97@end example
98
99* You can set several input files and output files:
100
101@example
e99c4e10 102ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
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103@end example
104
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105Converts the audio file a.wav and the raw YUV video file a.yuv
106to MPEG file a.mpg.
9181577c 107
6bf40f39 108* You can also do audio and video conversions at the same time:
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109
110@example
e99c4e10 111ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
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112@end example
113
4c5f7207 114Converts a.wav to MPEG audio at 22050Hz sample rate.
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115
116* You can encode to several formats at the same time and define a
e99c4e10 117mapping from input stream to output streams:
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118
119@example
5438308f 120ffmpeg -i /tmp/a.wav -ab 64k /tmp/a.mp2 -ab 128k /tmp/b.mp2 -map 0:0 -map 0:0
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121@end example
122
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123Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
124file:index' specifies which input stream is used for each output
e99c4e10 125stream, in the order of the definition of output streams.
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126
127* You can transcode decrypted VOBs
128
129@example
5438308f 130ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800k -g 300 -bf 2 -acodec mp3 -ab 128k snatch.avi
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131@end example
132
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133This is a typical DVD ripping example; the input is a VOB file, the
134output an AVI file with MPEG-4 video and MP3 audio. Note that in this
135command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
136GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
137input video. Furthermore, the audio stream is MP3-encoded so you need
138to enable LAME support by passing @code{--enable-mp3lame} to configure.
139The mapping is particularly useful for DVD transcoding
e99c4e10 140to get the desired audio language.
9181577c 141
4c5f7207 142NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
e99c4e10 143@c man end
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144
145@chapter Invocation
146
147@section Syntax
148
e99c4e10 149The generic syntax is:
9181577c 150
115329f1 151@example
e99c4e10 152@c man begin SYNOPSIS
28f88dc8 153ffmpeg [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}...
e99c4e10 154@c man end
9181577c 155@end example
e99c4e10 156@c man begin DESCRIPTION
e99c4e10 157As a general rule, options are applied to the next specified
699e77b1 158file. Therefore, order is important, and you can have the same
8cc62264 159option on the command line multiple times. Each occurrence is
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160then applied to the next input or output file.
161
eb10acec 162* To set the video bitrate of the output file to 64kbit/s:
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163@example
164ffmpeg -i input.avi -b 64k output.avi
165@end example
166
167* To force the frame rate of the input and output file to 24 fps:
168@example
169ffmpeg -r 24 -i input.avi output.avi
170@end example
171
172* To force the frame rate of the output file to 24 fps:
173@example
174ffmpeg -i input.avi -r 24 output.avi
175@end example
176
177* To force the frame rate of input file to 1 fps and the output file to 24 fps:
178@example
179ffmpeg -r 1 -i input.avi -r 24 output.avi
180@end example
181
182The format option may be needed for raw input files.
9181577c 183
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184By default, FFmpeg tries to convert as losslessly as possible: It
185uses the same audio and video parameters for the outputs as the one
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186specified for the inputs.
187@c man end
9181577c 188
e99c4e10 189@c man begin OPTIONS
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190@section Main options
191
e99c4e10 192@table @option
9181577c 193@item -L
4c5f7207 194Show license.
18bff752 195
9181577c 196@item -h
4c5f7207 197Show help.
18bff752 198
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199@item -version
200Show version.
201
e99c4e10 202@item -formats
4c5f7207 203Show available formats, codecs, protocols, ...
18bff752 204
115329f1 205@item -f fmt
4c5f7207 206Force format.
18bff752 207
115329f1 208@item -i filename
4c5f7207 209input filename
9181577c 210
115329f1 211@item -y
4c5f7207 212Overwrite output files.
9181577c 213
115329f1 214@item -t duration
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215Set the recording time in seconds.
216@code{hh:mm:ss[.xxx]} syntax is also supported.
9181577c 217
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218@item -fs limit_size
219Set the file size limit.
220
e83a84ac 221@item -ss position
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222Seek to given time position in seconds.
223@code{hh:mm:ss[.xxx]} syntax is also supported.
e83a84ac 224
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225@item -itsoffset offset
226Set the input time offset in seconds.
227@code{[-]hh:mm:ss[.xxx]} syntax is also supported.
228This option affects all the input files that follow it.
229The offset is added to the timestamps of the input files.
230Specifying a positive offset means that the corresponding
231streams are delayed by 'offset' seconds.
232
115329f1 233@item -title string
4c5f7207 234Set the title.
9181577c 235
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236@item -timestamp time
237Set the timestamp.
238
115329f1 239@item -author string
4c5f7207 240Set the author.
9181577c 241
115329f1 242@item -copyright string
4c5f7207 243Set the copyright.
9181577c 244
115329f1 245@item -comment string
4c5f7207 246Set the comment.
9181577c 247
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248@item -album string
249Set the album.
250
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251@item -track number
252Set the track.
253
254@item -year number
255Set the year.
256
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257@item -v verbose
258Control amount of logging.
259
99db6420 260@item -target type
4386f941 261Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50", "pal-vcd",
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262"ntsc-svcd", ... ). All the format options (bitrate, codecs,
263buffer sizes) are then set automatically. You can just type:
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264
265@example
266ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
267@end example
268
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269Nevertheless you can specify additional options as long as you know
270they do not conflict with the standard, as in:
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271
272@example
273ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
274@end example
275
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276@item -dframes number
277Set the number of data frames to record.
278
279@item -scodec codec
280Force subtitle codec ('copy' to copy stream).
281
282@item -newsubtitle
283Add a new subtitle stream to the current output stream.
284
285@item -slang code
286Set the ISO 639 language code (3 letters) of the current subtitle stream.
401fbdde 287
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288@end table
289
290@section Video Options
291
e99c4e10 292@table @option
9181577c 293@item -b bitrate
3c0ba870 294Set the video bitrate in bit/s (default = 200 kb/s).
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295@item -vframes number
296Set the number of video frames to record.
115329f1 297@item -r fps
4386f941 298Set frame rate (Hz value, fraction or abbreviation), (default = 25).
115329f1 299@item -s size
67053c30 300Set frame size. The format is @samp{wxh} (ffserver default = 160x128, ffmpeg default = same as source).
4c5f7207 301The following abbreviations are recognized:
5ee03c86 302@table @samp
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303@item sqcif
304128x96
305@item qcif
306176x144
307@item cif
308352x288
309@item 4cif
310704x576
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311@item qqvga
312160x120
313@item qvga
314320x240
315@item vga
316640x480
317@item svga
318800x600
319@item xga
3201024x768
321@item uxga
3221600x1200
323@item qxga
3242048x1536
325@item sxga
3261280x1024
327@item qsxga
3282560x2048
329@item hsxga
3305120x4096
331@item wvga
332852x480
333@item wxga
3341366x768
335@item wsxga
3361600x1024
337@item wuxga
3381920x1200
339@item woxga
3402560x1600
341@item wqsxga
3423200x2048
343@item wquxga
3443840x2400
345@item whsxga
3466400x4096
347@item whuxga
3487680x4800
349@item cga
350320x200
351@item ega
352640x350
353@item hd480
354852x480
355@item hd720
3561280x720
357@item hd1080
3581920x1080
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359@end table
360
361@item -aspect aspect
4c5f7207 362Set aspect ratio (4:3, 16:9 or 1.3333, 1.7777).
18bff752 363@item -croptop size
4c5f7207 364Set top crop band size (in pixels).
18bff752 365@item -cropbottom size
4c5f7207 366Set bottom crop band size (in pixels).
18bff752 367@item -cropleft size
4c5f7207 368Set left crop band size (in pixels).
18bff752 369@item -cropright size
4c5f7207 370Set right crop band size (in pixels).
1ff93ffc 371@item -padtop size
4c5f7207 372Set top pad band size (in pixels).
1ff93ffc 373@item -padbottom size
4c5f7207 374Set bottom pad band size (in pixels).
1ff93ffc 375@item -padleft size
4c5f7207 376Set left pad band size (in pixels).
1ff93ffc 377@item -padright size
4c5f7207 378Set right pad band size (in pixels).
5b79a73e 379@item -padcolor (hex color)
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380Set color of padded bands. The value for padcolor is expressed
381as a six digit hexadecimal number where the first two digits
382represent red, the middle two digits green and last two digits
383blue (default = 000000 (black)).
9181577c 384@item -vn
4c5f7207 385Disable video recording.
115329f1 386@item -bt tolerance
dc5ee8bc 387Set video bitrate tolerance (in bit/s).
18bff752 388@item -maxrate bitrate
a5515106 389Set max video bitrate tolerance (in bit/s).
18bff752 390@item -minrate bitrate
a5515106 391Set min video bitrate tolerance (in bit/s).
18bff752 392@item -bufsize size
81d0618f 393Set rate control buffer size (in bits).
115329f1 394@item -vcodec codec
4c5f7207 395Force video codec to @var{codec}. Use the @code{copy} special value to
5ee03c86 396tell that the raw codec data must be copied as is.
18bff752 397@item -sameq
4c5f7207 398Use same video quality as source (implies VBR).
9181577c 399
115329f1 400@item -pass n
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401Select the pass number (1 or 2). It is useful to do two pass
402encoding. The statistics of the video are recorded in the first
403pass and the video is generated at the exact requested bitrate
404in the second pass.
9181577c 405
115329f1 406@item -passlogfile file
4c5f7207 407Set two pass logfile name to @var{file}.
9181577c 408
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409@item -newvideo
410Add a new video stream to the current output stream.
411
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412@end table
413
18bff752 414@section Advanced Video Options
9181577c 415
e99c4e10 416@table @option
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417@item -pix_fmt format
418Set pixel format.
115329f1 419@item -g gop_size
4c5f7207 420Set the group of pictures size.
115329f1 421@item -intra
4c5f7207 422Use only intra frames.
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423@item -vdt n
424Discard threshold.
115329f1 425@item -qscale q
4bef236b 426Use fixed video quantizer scale (VBR).
115329f1 427@item -qmin q
4bef236b 428minimum video quantizer scale (VBR)
115329f1 429@item -qmax q
4bef236b 430maximum video quantizer scale (VBR)
115329f1 431@item -qdiff q
4bef236b 432maximum difference between the quantizer scales (VBR)
115329f1 433@item -qblur blur
4bef236b 434video quantizer scale blur (VBR)
115329f1 435@item -qcomp compression
4bef236b 436video quantizer scale compression (VBR)
18bff752 437
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438@item -lmin lambda
439minimum video lagrange factor (VBR)
440@item -lmax lambda
441max video lagrange factor (VBR)
442@item -mblmin lambda
443minimum macroblock quantizer scale (VBR)
444@item -mblmax lambda
445maximum macroblock quantizer scale (VBR)
446
447These four options (lmin, lmax, mblmin, mblmax) use 'lambda' units,
448but you may use the QP2LAMBDA constant to easily convert from 'q' units:
449@example
450ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
451@end example
452
18bff752 453@item -rc_init_cplx complexity
4c5f7207 454initial complexity for single pass encoding
18bff752 455@item -b_qfactor factor
4c5f7207 456qp factor between P- and B-frames
18bff752 457@item -i_qfactor factor
4c5f7207 458qp factor between P- and I-frames
18bff752 459@item -b_qoffset offset
4c5f7207 460qp offset between P- and B-frames
18bff752 461@item -i_qoffset offset
4c5f7207 462qp offset between P- and I-frames
18bff752 463@item -rc_eq equation
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464Set rate control equation (@pxref{FFmpeg formula
465evaluator}) (default = @code{tex^qComp}).
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466@item -rc_override override
467rate control override for specific intervals
18bff752 468@item -me method
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469Set motion estimation method to @var{method}.
470Available methods are (from lowest to best quality):
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471@table @samp
472@item zero
5ee03c86 473Try just the (0, 0) vector.
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474@item phods
475@item log
476@item x1
477@item epzs
478(default method)
479@item full
480exhaustive search (slow and marginally better than epzs)
481@end table
482
483@item -dct_algo algo
4c5f7207 484Set DCT algorithm to @var{algo}. Available values are:
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485@table @samp
486@item 0
487FF_DCT_AUTO (default)
488@item 1
489FF_DCT_FASTINT
490@item 2
491FF_DCT_INT
492@item 3
493FF_DCT_MMX
494@item 4
495FF_DCT_MLIB
496@item 5
497FF_DCT_ALTIVEC
498@end table
499
500@item -idct_algo algo
4c5f7207 501Set IDCT algorithm to @var{algo}. Available values are:
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502@table @samp
503@item 0
504FF_IDCT_AUTO (default)
505@item 1
115329f1 506FF_IDCT_INT
18bff752 507@item 2
115329f1 508FF_IDCT_SIMPLE
18bff752 509@item 3
115329f1 510FF_IDCT_SIMPLEMMX
18bff752 511@item 4
115329f1 512FF_IDCT_LIBMPEG2MMX
18bff752 513@item 5
115329f1 514FF_IDCT_PS2
18bff752 515@item 6
115329f1 516FF_IDCT_MLIB
18bff752 517@item 7
115329f1 518FF_IDCT_ARM
18bff752 519@item 8
115329f1 520FF_IDCT_ALTIVEC
18bff752 521@item 9
115329f1 522FF_IDCT_SH4
18bff752 523@item 10
115329f1 524FF_IDCT_SIMPLEARM
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525@end table
526
527@item -er n
4c5f7207 528Set error resilience to @var{n}.
18bff752 529@table @samp
115329f1 530@item 1
1471c6c2 531FF_ER_CAREFUL (default)
18bff752 532@item 2
5ee03c86 533FF_ER_COMPLIANT
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534@item 3
535FF_ER_AGGRESSIVE
536@item 4
537FF_ER_VERY_AGGRESSIVE
538@end table
539
5ee03c86 540@item -ec bit_mask
4c5f7207 541Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of
5ee03c86 542the following values:
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543@table @samp
544@item 1
4c5f7207 545FF_EC_GUESS_MVS (default = enabled)
18bff752 546@item 2
4c5f7207 547FF_EC_DEBLOCK (default = enabled)
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548@end table
549
550@item -bf frames
4c5f7207 551Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4).
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552@item -mbd mode
553macroblock decision
554@table @samp
555@item 0
4c5f7207 556FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in FFmpeg).
18bff752 557@item 1
4c5f7207 558FF_MB_DECISION_BITS: Choose the one which needs the fewest bits.
18bff752 559@item 2
019c8838 560FF_MB_DECISION_RD: rate distortion
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561@end table
562
563@item -4mv
4c5f7207 564Use four motion vector by macroblock (MPEG-4 only).
18bff752 565@item -part
4c5f7207 566Use data partitioning (MPEG-4 only).
18bff752 567@item -bug param
4c5f7207 568Work around encoder bugs that are not auto-detected.
18bff752 569@item -strict strictness
4c5f7207 570How strictly to follow the standards.
5ee03c86 571@item -aic
4c5f7207 572Enable Advanced intra coding (h263+).
5ee03c86 573@item -umv
4c5f7207 574Enable Unlimited Motion Vector (h263+)
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575
576@item -deinterlace
4c5f7207 577Deinterlace pictures.
3841e813 578@item -ilme
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579Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
580Use this option if your input file is interlaced and you want
581to keep the interlaced format for minimum losses.
582The alternative is to deinterlace the input stream with
583@option{-deinterlace}, but deinterlacing introduces losses.
18bff752 584@item -psnr
4c5f7207 585Calculate PSNR of compressed frames.
18bff752 586@item -vstats
4c5f7207 587Dump video coding statistics to @file{vstats_HHMMSS.log}.
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588@item -vstats_file file
589Dump video coding statistics to @var{file}.
18bff752 590@item -vhook module
4c5f7207 591Insert video processing @var{module}. @var{module} contains the module
18bff752 592name and its parameters separated by spaces.
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593@item -top n
594top=1/bottom=0/auto=-1 field first
595@item -dc precision
596Intra_dc_precision.
597@item -vtag fourcc/tag
598Force video tag/fourcc.
599@item -qphist
600Show QP histogram.
601@item -vbsf bitstream filter
602Bitstream filters available are "dump_extra", "remove_extra", "noise".
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603@end table
604
605@section Audio Options
606
607@table @option
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608@item -aframes number
609Set the number of audio frames to record.
115329f1 610@item -ar freq
4c5f7207 611Set the audio sampling frequency (default = 44100 Hz).
115329f1 612@item -ab bitrate
5438308f 613Set the audio bitrate in bit/s (default = 64k).
18bff752 614@item -ac channels
4c5f7207 615Set the number of audio channels (default = 1).
5ee03c86 616@item -an
4c5f7207 617Disable audio recording.
5ee03c86 618@item -acodec codec
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619Force audio codec to @var{codec}. Use the @code{copy} special value to
620specify that the raw codec data must be copied as is.
de62a89d 621@item -newaudio
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622Add a new audio track to the output file. If you want to specify parameters,
623do so before @code{-newaudio} (@code{-acodec}, @code{-ab}, etc..).
de62a89d 624
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625Mapping will be done automatically, if the number of output streams is equal to
626the number of input streams, else it will pick the first one that matches. You
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627can override the mapping using @code{-map} as usual.
628
629Example:
630@example
5438308f 631ffmpeg -i file.mpg -vcodec copy -acodec ac3 -ab 384k test.mpg -acodec mp2 -ab 192k -newaudio
de62a89d 632@end example
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633@item -alang code
634Set the ISO 639 language code (3 letters) of the current audio stream.
635@end table
636
637@section Advanced Audio options:
638
639@table @option
640@item -atag fourcc/tag
641Force audio tag/fourcc.
642@item -absf bitstream filter
643Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp".
644@end table
645
646@section Subtitle options:
647
648@table @option
649@item -scodec codec
650Force subtitle codec ('copy' to copy stream).
651@item -newsubtitle
652Add a new subtitle stream to the current output stream.
653@item -slang code
654Set the ISO 639 language code (3 letters) of the current subtitle stream.
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655@end table
656
657@section Audio/Video grab options
658
659@table @option
18bff752 660@item -vc channel
4c5f7207 661Set video grab channel (DV1394 only).
18bff752 662@item -tvstd standard
4c5f7207 663Set television standard (NTSC, PAL (SECAM)).
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664@item -isync
665Synchronize read on input.
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666@end table
667
668@section Advanced options
669
670@table @option
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671@item -map input stream id[:input stream id]
672Set stream mapping from input streams to output streams.
673Just enumerate the input streams in the order you want them in the output.
674[input stream id] sets the (input) stream to sync against.
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675@item -map_meta_data outfile:infile
676Set meta data information of outfile from infile.
18bff752 677@item -debug
4c5f7207 678Print specific debug info.
115329f1 679@item -benchmark
4c5f7207 680Add timings for benchmarking.
4386f941 681@item -dump
4c5f7207 682Dump each input packet.
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683@item -hex
684When dumping packets, also dump the payload.
18bff752 685@item -bitexact
4c5f7207 686Only use bit exact algorithms (for codec testing).
18bff752 687@item -ps size
4c5f7207 688Set packet size in bits.
5ee03c86 689@item -re
4c5f7207 690Read input at native frame rate. Mainly used to simulate a grab device.
4386f941 691@item -loop_input
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692Loop over the input stream. Currently it works only for image
693streams. This option is used for automatic FFserver testing.
8108551a 694@item -loop_output number_of_times
019c8838 695Repeatedly loop output for formats that support looping such as animated GIF
4c5f7207 696(0 will loop the output infinitely).
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697@item -threads count
698Thread count.
c52e13f1 699@item -vsync parameter
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700Video sync method. Video will be stretched/squeezed to match the timestamps,
701it is done by duplicating and dropping frames. With -map you can select from
702which stream the timestamps should be taken. You can leave either video or
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703audio unchanged and sync the remaining stream(s) to the unchanged one.
704@item -async samples_per_second
29c9183c 705Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
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706the parameter is the maximum samples per second by which the audio is changed.
707-async 1 is a special case where only the start of the audio stream is corrected
708without any later correction.
9181577c 709@end table
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710
711@node FFmpeg formula evaluator
712@section FFmpeg formula evaluator
713
714When evaluating a rate control string, FFmpeg uses an internal formula
115329f1 715evaluator.
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716
717The following binary operators are available: @code{+}, @code{-},
718@code{*}, @code{/}, @code{^}.
719
720The following unary operators are available: @code{+}, @code{-},
721@code{(...)}.
722
723The following functions are available:
724@table @var
725@item sinh(x)
726@item cosh(x)
727@item tanh(x)
728@item sin(x)
729@item cos(x)
730@item tan(x)
731@item exp(x)
732@item log(x)
733@item squish(x)
734@item gauss(x)
735@item abs(x)
736@item max(x, y)
737@item min(x, y)
738@item gt(x, y)
739@item lt(x, y)
740@item eq(x, y)
741@item bits2qp(bits)
742@item qp2bits(qp)
743@end table
744
745The following constants are available:
746@table @var
747@item PI
748@item E
749@item iTex
750@item pTex
751@item tex
752@item mv
753@item fCode
754@item iCount
755@item mcVar
756@item var
757@item isI
758@item isP
759@item isB
760@item avgQP
761@item qComp
762@item avgIITex
763@item avgPITex
764@item avgPPTex
765@item avgBPTex
766@item avgTex
767@end table
768
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769@c man end
770
771@ignore
772
773@setfilename ffmpeg
774@settitle FFmpeg video converter
775
776@c man begin SEEALSO
019c8838 777ffserver(1), ffplay(1) and the HTML documentation of @file{ffmpeg}.
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778@c man end
779
780@c man begin AUTHOR
781Fabrice Bellard
782@c man end
783
784@end ignore
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785
786@section Protocols
787
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788The filename can be @file{-} to read from standard input or to write
789to standard output.
9181577c 790
4c5f7207 791FFmpeg also handles many protocols specified with an URL syntax.
9181577c 792
4c5f7207 793Use 'ffmpeg -formats' to see a list of the supported protocols.
9181577c 794
e99c4e10 795The protocol @code{http:} is currently used only to communicate with
4c5f7207 796FFserver (see the FFserver documentation). When FFmpeg will be a
e99c4e10 797video player it will also be used for streaming :-)
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798
799@chapter Tips
800
801@itemize
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802@item For streaming at very low bitrate application, use a low frame rate
803and a small GOP size. This is especially true for RealVideo where
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804the Linux player does not seem to be very fast, so it can miss
805frames. An example is:
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806
807@example
3c0ba870 808ffmpeg -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
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809@end example
810
811@item The parameter 'q' which is displayed while encoding is the current
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812quantizer. The value 1 indicates that a very good quality could
813be achieved. The value 31 indicates the worst quality. If q=31 appears
e99c4e10 814too often, it means that the encoder cannot compress enough to meet
4c5f7207 815your bitrate. You must either increase the bitrate, decrease the
e99c4e10 816frame rate or decrease the frame size.
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817
818@item If your computer is not fast enough, you can speed up the
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819compression at the expense of the compression ratio. You can use
820'-me zero' to speed up motion estimation, and '-intra' to disable
4c5f7207 821motion estimation completely (you have only I-frames, which means it
e99c4e10 822is about as good as JPEG compression).
9181577c 823
4c5f7207 824@item To have very low audio bitrates, reduce the sampling frequency
019c8838 825(down to 22050 kHz for MPEG audio, 22050 or 11025 for AC3).
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826
827@item To have a constant quality (but a variable bitrate), use the option
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828'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
829quality).
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830
831@item When converting video files, you can use the '-sameq' option which
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832uses the same quality factor in the encoder as in the decoder.
833It allows almost lossless encoding.
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834
835@end itemize
836
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837
838@chapter external libraries
839
840FFmpeg can be hooked up with a number of external libraries to add support
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841for more formats. None of them are used by default, their use has to be
842explicitly requested by passing the appropriate flags to @file{./configure}.
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843
844@section AMR
845
846AMR comes in two different flavors, WB and NB. FFmpeg can make use of the
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847AMR WB (floating-point mode) and the AMR NB (floating-point mode) reference
848decoders and encoders.
47404f9f 849
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850Go to @url{http://www.penguin.cz/~utx/amr} and follow the instructions for
851installing the libraries. Then pass @code{--enable-amr-nb} and/or
852@code{--enable-amr-wb} to configure to enable the libraries.
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853
854
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855@chapter Supported File Formats and Codecs
856
857You can use the @code{-formats} option to have an exhaustive list.
858
859@section File Formats
860
6bf40f39 861FFmpeg supports the following file formats through the @code{libavformat}
0699d2fe 862library:
9181577c 863
3fc9e78f 864@multitable @columnfractions .4 .1 .1 .4
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865@item Supported File Format @tab Encoding @tab Decoding @tab Comments
866@item MPEG audio @tab X @tab X
4c5f7207 867@item MPEG-1 systems @tab X @tab X
9181577c 868@tab muxed audio and video
4c5f7207 869@item MPEG-2 PS @tab X @tab X
9181577c 870@tab also known as @code{VOB} file
4c5f7207 871@item MPEG-2 TS @tab @tab X
9181577c 872@tab also known as DVB Transport Stream
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873@item ASF@tab X @tab X
874@item AVI@tab X @tab X
875@item WAV@tab X @tab X
9181577c 876@item Macromedia Flash@tab X @tab X
4c5f7207 877@tab Only embedded audio is decoded.
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878@item FLV @tab X @tab X
879@tab Macromedia Flash video files
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880@item Real Audio and Video @tab X @tab X
881@item Raw AC3 @tab X @tab X
882@item Raw MJPEG @tab X @tab X
883@item Raw MPEG video @tab X @tab X
884@item Raw PCM8/16 bits, mulaw/Alaw@tab X @tab X
885@item Raw CRI ADX audio @tab X @tab X
886@item Raw Shorten audio @tab @tab X
887@item SUN AU format @tab X @tab X
7fe4c823 888@item NUT @tab X @tab X @tab NUT Open Container Format
115329f1 889@item QuickTime @tab X @tab X
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890@item MPEG-4 @tab X @tab X
891@tab MPEG-4 is a variant of QuickTime.
115329f1 892@item Raw MPEG4 video @tab X @tab X
4fa1c4fa 893@item DV @tab X @tab X
701b603d 894@item 4xm @tab @tab X
4c5f7207 895@tab 4X Technologies format, used in some games.
4d3b1f8d 896@item Playstation STR @tab @tab X
13dec857 897@item Id RoQ @tab X @tab X
4c5f7207 898@tab Used in Quake III, Jedi Knight 2, other computer games.
4d3b1f8d 899@item Interplay MVE @tab @tab X
4c5f7207 900@tab Format used in various Interplay computer games.
b17e9c99 901@item WC3 Movie @tab @tab X
4c5f7207 902@tab Multimedia format used in Origin's Wing Commander III computer game.
2fdf638b 903@item Sega FILM/CPK @tab @tab X
4c5f7207 904@tab Used in many Sega Saturn console games.
2fdf638b 905@item Westwood Studios VQA/AUD @tab @tab X
4c5f7207 906@tab Multimedia formats used in Westwood Studios games.
4120a53a 907@item Id Cinematic (.cin) @tab @tab X
4c5f7207 908@tab Used in Quake II.
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909@item FLIC format @tab @tab X
910@tab .fli/.flc files
da00f30e 911@item Sierra VMD @tab @tab X
4c5f7207 912@tab Used in Sierra CD-ROM games.
d08d7142 913@item Sierra Online @tab @tab X
4c5f7207 914@tab .sol files used in Sierra Online games.
38088adf 915@item Matroska @tab @tab X
ad81a9fe 916@item Electronic Arts Multimedia @tab @tab X
4c5f7207 917@tab Used in various EA games; files have extensions like WVE and UV2.
353147ed 918@item Nullsoft Video (NSV) format @tab @tab X
4accd1fd 919@item ADTS AAC audio @tab X @tab X
ea395e8c 920@item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro.
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921@item American Laser Games MM @tab @tab X
922@tab Multimedia format used in games like Mad Dog McCree
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923@item AVS @tab @tab X
924@tab Multimedia format used by the Creature Shock game.
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925@item Smacker @tab @tab X
926@tab Multimedia format used by many games.
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927@item GXF @tab X @tab X
928@tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.
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929@item CIN @tab @tab X
930@tab Multimedia format used by Delphine Software games.
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931@item MXF @tab @tab X
932@tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
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933@item SEQ @tab @tab X
934@tab Tiertex .seq files used in the DOS CDROM version of the game Flashback.
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935@item DXA @tab @tab X
936@tab This format is used in non-Windows version of Feeble Files game and
937different game cutscenes repacked for use with ScummVM.
efb0c399 938@item THP @tab @tab X
d1e0d21f 939@tab Used on the Nintendo GameCube.
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940@item C93 @tab @tab X
941@tab Used in the game Cyberia from Interplay.
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942@item Bethsoft VID @tab @tab X
943@tab Used in some games from Bethesda Softworks.
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944@item CRYO APC @tab @tab X
945@tab Audio format used in some games by CRYO Interactive Entertainment.
353147ed 946@end multitable
9181577c 947
4c5f7207 948@code{X} means that encoding (resp. decoding) is supported.
9181577c 949
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950@section Image Formats
951
952FFmpeg can read and write images for each frame of a video sequence. The
953following image formats are supported:
954
3fc9e78f 955@multitable @columnfractions .4 .1 .1 .4
0699d2fe 956@item Supported Image Format @tab Encoding @tab Decoding @tab Comments
115329f1 957@item PGM, PPM @tab X @tab X
4c5f7207 958@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
2eb5d024 959@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
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960@item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
961@item .Y.U.V @tab X @tab X @tab one raw file per component
962@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
963@item PNG @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
3689cf16 964@item Targa @tab @tab X @tab Targa (.TGA) image format.
716222db 965@item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
6a91ec51 966@item SGI @tab X @tab X @tab SGI RGB image format
d58bbf81 967@item PTX @tab @tab X @tab V.Flash PTX format
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968@end multitable
969
4c5f7207 970@code{X} means that encoding (resp. decoding) is supported.
0699d2fe 971
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972@section Video Codecs
973
3fc9e78f 974@multitable @columnfractions .4 .1 .1 .4
9181577c 975@item Supported Codec @tab Encoding @tab Decoding @tab Comments
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976@item MPEG-1 video @tab X @tab X
977@item MPEG-2 video @tab X @tab X
2bc5da7b 978@item MPEG-4 @tab X @tab X
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979@item MSMPEG4 V1 @tab X @tab X
980@item MSMPEG4 V2 @tab X @tab X
2bc5da7b 981@item MSMPEG4 V3 @tab X @tab X
9181577c 982@item WMV7 @tab X @tab X
4c5f7207 983@item WMV8 @tab X @tab X @tab not completely working
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984@item WMV9 @tab @tab X @tab not completely working
985@item VC1 @tab @tab X
b06b45c4 986@item H.261 @tab X @tab X
4c5f7207 987@item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0
b06b45c4 988@item H.264 @tab @tab X
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989@item RealVideo 1.0 @tab X @tab X
990@item RealVideo 2.0 @tab X @tab X
115329f1 991@item MJPEG @tab X @tab X
4c5f7207 992@item lossless MJPEG @tab X @tab X
26d6d032 993@item JPEG-LS @tab X @tab X @tab fourcc: MJLS, lossless and near-lossless is supported
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994@item Apple MJPEG-B @tab @tab X
995@item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X
115329f1 996@item DV @tab X @tab X
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997@item HuffYUV @tab X @tab X
998@item FFmpeg Video 1 @tab X @tab X @tab experimental lossless codec (fourcc: FFV1)
999@item FFmpeg Snow @tab X @tab X @tab experimental wavelet codec (fourcc: SNOW)
701b603d 1000@item Asus v1 @tab X @tab X @tab fourcc: ASV1
4d3b1f8d 1001@item Asus v2 @tab X @tab X @tab fourcc: ASV2
701b603d 1002@item Creative YUV @tab @tab X @tab fourcc: CYUV
d2bfadc0 1003@item Sorenson Video 1 @tab X @tab X @tab fourcc: SVQ1
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1004@item Sorenson Video 3 @tab @tab X @tab fourcc: SVQ3
1005@item On2 VP3 @tab @tab X @tab still experimental
5ce117c3 1006@item On2 VP5 @tab @tab X @tab fourcc: VP50
9110a0e3 1007@item On2 VP6 @tab @tab X @tab fourcc: VP60,VP61,VP62
150d2772 1008@item Theora @tab X @tab X @tab still experimental
cdb2c1ca 1009@item Intel Indeo 3 @tab @tab X
9303d49c 1010@item FLV @tab X @tab X @tab Sorenson H.263 used in Flash
15419468 1011@item Flash Screen Video @tab X @tab X @tab fourcc: FSV1
4d3b1f8d 1012@item ATI VCR1 @tab @tab X @tab fourcc: VCR1
7fe4c823 1013@item ATI VCR2 @tab @tab X @tab fourcc: VCR2
4d3b1f8d 1014@item Cirrus Logic AccuPak @tab @tab X @tab fourcc: CLJR
4c5f7207 1015@item 4X Video @tab @tab X @tab Used in certain computer games.
115329f1 1016@item Sony Playstation MDEC @tab @tab X
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1017@item Id RoQ @tab @tab X @tab Used in Quake III, Jedi Knight 2, other computer games.
1018@item Xan/WC3 @tab @tab X @tab Used in Wing Commander III .MVE files.
1019@item Interplay Video @tab @tab X @tab Used in Interplay .MVE files.
070ed1bc 1020@item Apple Animation @tab @tab X @tab fourcc: 'rle '
42cad81a 1021@item Apple Graphics @tab @tab X @tab fourcc: 'smc '
2fdf638b 1022@item Apple Video @tab @tab X @tab fourcc: rpza
d08d7142 1023@item Apple QuickDraw @tab @tab X @tab fourcc: qdrw
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1024@item Cinepak @tab @tab X
1025@item Microsoft RLE @tab @tab X
1026@item Microsoft Video-1 @tab @tab X
4120a53a 1027@item Westwood VQA @tab @tab X
4c5f7207 1028@item Id Cinematic Video @tab @tab X @tab Used in Quake II.
1dc1ed99 1029@item Planar RGB @tab @tab X @tab fourcc: 8BPS
42cad81a 1030@item FLIC video @tab @tab X
9a4117d5 1031@item Duck TrueMotion v1 @tab @tab X @tab fourcc: DUCK
dce76c20 1032@item Duck TrueMotion v2 @tab @tab X @tab fourcc: TM20
4c5f7207 1033@item VMD Video @tab @tab X @tab Used in Sierra VMD files.
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1034@item MSZH @tab @tab X @tab Part of LCL
1035@item ZLIB @tab X @tab X @tab Part of LCL, encoder experimental
9d53d58e 1036@item TechSmith Camtasia @tab @tab X @tab fourcc: TSCC
d0a0bbd2 1037@item IBM Ultimotion @tab @tab X @tab fourcc: ULTI
ab711b3c 1038@item Miro VideoXL @tab @tab X @tab fourcc: VIXL
acfd8f0f 1039@item QPEG @tab @tab X @tab fourccs: QPEG, Q1.0, Q1.1
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1040@item LOCO @tab @tab X @tab
1041@item Winnov WNV1 @tab @tab X @tab
589f8220 1042@item Autodesk Animator Studio Codec @tab @tab X @tab fourcc: AASC
115329f1 1043@item Fraps FPS1 @tab @tab X @tab
2b6c1d80 1044@item CamStudio @tab @tab X @tab fourcc: CSCD
4e114829 1045@item American Laser Games Video @tab @tab X @tab Used in games like Mad Dog McCree
f48d6e1b 1046@item ZMBV @tab X @tab X @tab Encoder works only on PAL8
26376701 1047@item AVS Video @tab @tab X @tab Video encoding used by the Creature Shock game.
348efc18 1048@item Smacker Video @tab @tab X @tab Video encoding used in Smacker.
dfca23e3 1049@item RTjpeg @tab @tab X @tab Video encoding used in NuppelVideo files.
fd7b1991 1050@item KMVC @tab @tab X @tab Codec used in Worms games.
eb57c889 1051@item VMware Video @tab @tab X @tab Codec used in videos captured by VMware.
dc56e0de 1052@item Cin Video @tab @tab X @tab Codec used in Delphine Software games.
29f86228 1053@item Tiertex Seq Video @tab @tab X @tab Codec used in DOS CDROM FlashBack game.
33a0dd37 1054@item DXA Video @tab @tab X @tab Codec originally used in Feeble Files game.
52b6bad2 1055@item AVID DNxHD @tab @tab X @tab aka SMPTE VC3
9a0ddd09 1056@item C93 Video @tab @tab X @tab Codec used in Cyberia game.
8845202e 1057@item THP @tab @tab X @tab Used on the Nintendo GameCube.
1e6c6759 1058@item Bethsoft VID @tab @tab X @tab Used in some games from Bethesda Softworks.
12b6d7c0 1059@item Renderware TXD @tab @tab X @tab Texture dictionaries used by the Renderware Engine.
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1060@end multitable
1061
4c5f7207 1062@code{X} means that encoding (resp. decoding) is supported.
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1063
1064@section Audio Codecs
1065
1066@multitable @columnfractions .4 .1 .1 .1 .7
1067@item Supported Codec @tab Encoding @tab Decoding @tab Comments
115329f1 1068@item MPEG audio layer 2 @tab IX @tab IX
9181577c 1069@item MPEG audio layer 1/3 @tab IX @tab IX
4c5f7207 1070@tab MP3 encoding is supported through the external library LAME.
37776c3b 1071@item AC3 @tab IX @tab IX
4c5f7207 1072@tab liba52 is used internally for decoding.
34d7008d 1073@item Vorbis @tab X @tab X
74882049 1074@item WMA V1/V2 @tab X @tab X
f6fa7a6c 1075@item AAC @tab X @tab X
4c5f7207 1076@tab Supported through the external library libfaac/libfaad.
d4c3c5a6 1077@item Microsoft ADPCM @tab X @tab X
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1078@item MS IMA ADPCM @tab X @tab X
1079@item QT IMA ADPCM @tab @tab X
1080@item 4X IMA ADPCM @tab @tab X
d4e437df 1081@item G.726 ADPCM @tab X @tab X
b17e9c99 1082@item Duck DK3 IMA ADPCM @tab @tab X
4c5f7207 1083@tab Used in some Sega Saturn console games.
b17e9c99 1084@item Duck DK4 IMA ADPCM @tab @tab X
4c5f7207 1085@tab Used in some Sega Saturn console games.
2fdf638b 1086@item Westwood Studios IMA ADPCM @tab @tab X
4c5f7207 1087@tab Used in Westwood Studios games like Command and Conquer.
7d8379f2 1088@item SMJPEG IMA ADPCM @tab @tab X
4c5f7207 1089@tab Used in certain Loki game ports.
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1090@item CD-ROM XA ADPCM @tab @tab X
1091@item CRI ADX ADPCM @tab X @tab X
4c5f7207 1092@tab Used in Sega Dreamcast games.
7d8379f2 1093@item Electronic Arts ADPCM @tab @tab X
4c5f7207 1094@tab Used in various EA titles.
b3bfb299 1095@item Creative ADPCM @tab @tab X
2433f24f 1096@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
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1097@item THP ADPCM @tab @tab X
1098@tab Used on the Nintendo GameCube.
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1099@item RA144 @tab @tab X
1100@tab Real 14400 bit/s codec
1101@item RA288 @tab @tab X
1102@tab Real 28800 bit/s codec
37776c3b 1103@item RADnet @tab X @tab IX
4c5f7207 1104@tab Real low bitrate AC3 codec, liba52 is used for decoding.
2eb5d024 1105@item AMR-NB @tab X @tab X
4c5f7207 1106@tab Supported through an external library.
d663a1fd 1107@item AMR-WB @tab X @tab X
4c5f7207 1108@tab Supported through an external library.
2eb5d024 1109@item DV audio @tab @tab X
b09432ad 1110@item Id RoQ DPCM @tab X @tab X
4c5f7207 1111@tab Used in Quake III, Jedi Knight 2, other computer games.
4d3b1f8d 1112@item Interplay MVE DPCM @tab @tab X
4c5f7207 1113@tab Used in various Interplay computer games.
b17e9c99 1114@item Xan DPCM @tab @tab X
4c5f7207 1115@tab Used in Origin's Wing Commander IV AVI files.
d08d7142 1116@item Sierra Online DPCM @tab @tab X
4c5f7207 1117@tab Used in Sierra Online game audio files.
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1118@item Apple MACE 3 @tab @tab X
1119@item Apple MACE 6 @tab @tab X
bfd9a00f 1120@item FLAC lossless audio @tab X @tab X
13dfd2b9 1121@item Shorten lossless audio @tab @tab X
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1122@item Apple lossless audio @tab @tab X
1123@tab QuickTime fourcc 'alac'
33a4d8b1 1124@item FFmpeg Sonic @tab X @tab X
4c5f7207 1125@tab experimental lossy/lossless codec
d9b1c197
RT
1126@item Qdesign QDM2 @tab @tab X
1127@tab there are still some distortions
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1128@item Real COOK @tab @tab X
1129@tab All versions except 5.1 are supported
e839a994 1130@item DSP Group TrueSpeech @tab @tab X
3dc411c0 1131@item True Audio (TTA) @tab @tab X
348efc18 1132@item Smacker Audio @tab @tab X
730581f3 1133@item WavPack Audio @tab @tab X
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1134@item Cin Audio @tab @tab X
1135@tab Codec used in Delphine Software games.
84ed36da 1136@item Intel Music Coder @tab @tab X
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1137@item Musepack @tab @tab X
1138@tab Only SV7 is supported
01ca9ac3 1139@item DT$ Coherent Audio @tab @tab X
10e26bc7 1140@item ATRAC 3 @tab @tab X
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1141@end multitable
1142
4c5f7207 1143@code{X} means that encoding (resp. decoding) is supported.
9181577c 1144
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1145@code{I} means that an integer-only version is available, too (ensures high
1146performance on systems without hardware floating point support).
9181577c 1147
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1148@chapter Platform Specific information
1149
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1150@section BSD
1151
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1152BSD make will not build FFmpeg, you need to install and use GNU Make
1153(@file{gmake}).
1154
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1155@section Windows
1156
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1157To get help and instructions for using FFmpeg under Windows, check out
1158the FFmpeg Windows Help Forum at
1159@url{http://arrozcru.no-ip.org/ffmpeg/}.
1160
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1161@subsection Native Windows compilation
1162
1163@itemize
1164@item Install the current versions of MSYS and MinGW from
1165@url{http://www.mingw.org/}. You can find detailed installation
1166instructions in the download section and the FAQ.
1167
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1168NOTE: Use at least bash 3.1. Older versions are known to be failing on the
1169configure script.
1170
4c5f7207 1171@item If you want to test the FFplay, also download
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1172the MinGW development library of SDL 1.2.x
1173(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
4c5f7207 1174@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
50f52fcd 1175unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
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1176directory. Edit the @file{sdl-config} script so that it gives the
1177correct SDL directory when invoked.
50f52fcd 1178
e926e391 1179@item Extract the current version of FFmpeg.
115329f1 1180
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1181@item Start the MSYS shell (file @file{msys.bat}).
1182
4c5f7207
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1183@item Change to the FFmpeg directory and follow
1184 the instructions of how to compile FFmpeg (file
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1185@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
1186suffices. If you have problems using SDL, verify that
1187@file{sdl-config} can be launched from the MSYS command line.
1188
4c5f7207 1189@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
ce10ff8e 1190@file{make install}. Do not forget to copy @file{SDL.dll} to the place
4c5f7207 1191you launch @file{ffplay} from.
50f52fcd 1192
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1193@end itemize
1194
115329f1 1195Notes:
988a9f9e 1196@itemize
50f52fcd 1197
988a9f9e
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1198@item The target @file{make wininstaller} can be used to create a
1199Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
4c5f7207 1200must be copied to the FFmpeg directory in order to build the
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1201installer.
1202
4c5f7207 1203@item By using @code{./configure --enable-shared} when configuring FFmpeg,
988a9f9e
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1204you can build @file{avcodec.dll} and @file{avformat.dll}. With
1205@code{make install} you install the FFmpeg DLLs and the associated
115329f1 1206headers in @file{Program Files/FFmpeg}.
988a9f9e 1207
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1208@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
1209when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
988a9f9e 1210C++ @code{lib} tool to build @code{avcodec.lib} and
4c5f7207 1211@code{avformat.lib}. With these libraries you can link your Visual C++
be0efc0c 1212code directly with the FFmpeg DLLs (see below).
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1213
1214@end itemize
b030b284 1215
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1216@subsection Visual C++ compatibility
1217
1218FFmpeg will not compile under Visual C++ -- and it has too many
1219dependencies on the GCC compiler to make a port viable. However,
1220if you want to use the FFmpeg libraries in your own applications,
1221you can still compile those applications using Visual C++. An
1222important restriction to this is that you have to use the
1223dynamically linked versions of the FFmpeg libraries (i.e. the
1224DLLs), and you have to make sure that Visual-C++-compatible
1225import libraries are created during the FFmpeg build process.
1226
1227This description of how to use the FFmpeg libraries with Visual C++ is
1228based on Visual C++ 2005 Express Edition Beta 2. If you have a different
1229version, you might have to modify the procedures slightly.
1230
1231Here are the step-by-step instructions for building the FFmpeg libraries
1232so they can be used with Visual C++:
1233
1234@enumerate
1235
ce10ff8e 1236@item Install Visual C++ (if you have not done so already).
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1237
1238@item Install MinGW and MSYS as described above.
1239
1240@item Add a call to @file{vcvars32.bat} (which sets up the environment
1241variables for the Visual C++ tools) as the first line of
1242@file{msys.bat}. The standard location for @file{vcvars32.bat} is
1243@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
1244and the standard location for @file{msys.bat} is
1245@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
1246following line as the first line of @file{msys.bat}:
1247
1248@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
1249
1250@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
1251If you get a help message with the command line options of @code{link.exe},
1252this means your environment variables are set up correctly, the
1253Microsoft linker is on the path and will be used by FFmpeg to
1254create Visual-C++-compatible import libraries.
1255
e926e391 1256@item Extract the current version of FFmpeg and change to the FFmpeg directory.
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1257
1258@item Type the command
51d8321d 1259@code{./configure --enable-shared --disable-static --enable-memalign-hack}
ce10ff8e 1260to configure and, if that did not produce any errors,
51d8321d 1261type @code{make} to build FFmpeg.
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1262
1263@item The subdirectories @file{libavformat}, @file{libavcodec}, and
1264@file{libavutil} should now contain the files @file{avformat.dll},
1265@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
1266@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
1267DLLs to your System32 directory (typically @file{C:\Windows\System32}).
1268
1269@end enumerate
1270
1271And here is how to use these libraries with Visual C++:
1272
1273@enumerate
1274
1275@item Create a new console application ("File / New / Project") and then
1276select "Win32 Console Application". On the appropriate page of the
1277Application Wizard, uncheck the "Precompiled headers" option.
1278
1279@item Write the source code for your application, or, for testing, just
1280copy the code from an existing sample application into the source file
1281that Visual C++ has already created for you. (Note that your source
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DB
1282filehas to have a @code{.cpp} extension; otherwise, Visual C++ will not
1283compile the FFmpeg headers correctly because in C mode, it does not
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1284recognize the @code{inline} keyword.) For example, you can copy
1285@file{output_example.c} from the FFmpeg distribution (but you will
1286have to make minor modifications so the code will compile under
1287C++, see below).
1288
1289@item Open the "Project / Properties" dialog box. In the "Configuration"
1290combo box, select "All Configurations" so that the changes you make will
1291affect both debug and release builds. In the tree view on the left hand
1292side, select "C/C++ / General", then edit the "Additional Include
1293Directories" setting to contain the complete paths to the
1294@file{libavformat}, @file{libavcodec}, and @file{libavutil}
1295subdirectories of your FFmpeg directory. Note that the directories have
1296to be separated using semicolons. Now select "Linker / General" from the
1297tree view and edit the "Additional Library Directories" setting to
1298contain the same three directories.
1299
1300@item Still in the "Project / Properties" dialog box, select "Linker / Input"
1301from the tree view, then add the files @file{avformat.lib},
1302@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
1303Dependencies". Note that the names of the libraries have to be separated
1304using spaces.
1305
765c3440 1306@item Now, select "C/C++ / Code Generation" from the tree view. Select
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1307"Debug" in the "Configuration" combo box. Make sure that "Runtime
1308Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
1309the "Configuration" combo box and make sure that "Runtime Library" is
1310set to "Multi-threaded DLL".
1311
1312@item Click "OK" to close the "Project / Properties" dialog box and build
1313the application. Hopefully, it should compile and run cleanly. If you
1314used @file{output_example.c} as your sample application, you will get a
1315few compiler errors, but they are easy to fix. The first type of error
ce10ff8e 1316occurs because Visual C++ does not allow an @code{int} to be converted to
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MB
1317an @code{enum} without a cast. To solve the problem, insert the required
1318casts (this error occurs once for a @code{CodecID} and once for a
1319@code{CodecType}). The second type of error occurs because C++ requires
1320the return value of @code{malloc} to be cast to the exact type of the
1321pointer it is being assigned to. Visual C++ will complain that, for
1322example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
1323an explicit cast. So insert an explicit cast in these places to silence
1324the compiler. The third type of error occurs because the @code{snprintf}
1325library function is called @code{_snprintf} under Visual C++. So just
1326add an underscore to fix the problem. With these changes,
1327@file{output_example.c} should compile under Visual C++, and the
1328resulting executable should produce valid video files.
1329
1330@end enumerate
1331
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1332@subsection Cross compilation for Windows with Linux
1333
1334You must use the MinGW cross compilation tools available at
1335@url{http://www.mingw.org/}.
1336
4c5f7207 1337Then configure FFmpeg with the following options:
b030b284 1338@example
6b74787b 1339./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
b030b284 1340@end example
019c8838 1341(you can change the cross-prefix according to the prefix chosen for the
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1342MinGW tools).
1343
4c5f7207 1344Then you can easily test FFmpeg with Wine
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1345(@url{http://www.winehq.com/}).
1346
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1347@subsection Compilation under Cygwin
1348
1349Cygwin works very much like Unix.
1350
1351Just install your Cygwin with all the "Base" packages, plus the
1352following "Devel" ones:
1353@example
1354binutils, gcc-core, make, subversion
1355@end example
1356
1357Do not install binutils-20060709-1 (they are buggy on shared builds);
1358use binutils-20050610-1 instead.
1359
1360Then run
1361
1362@example
1363./configure --enable-static --disable-shared
1364@end example
1365
1366to make a static build or
1367
1368@example
1369./configure --enable-shared --disable-static
1370@end example
1371
1372to build shared libraries.
1373
1374If you want to build FFmpeg with additional libraries, download Cygwin
1375"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
1376and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
1377(@url{http://cygwinports.dotsrc.org/}).
1378
1379@subsection Crosscompilation for Windows under Cygwin
1380
ce10ff8e 1381With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
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DB
1382
1383Just install your Cygwin as explained before, plus these additional
1384"Devel" packages:
1385@example
1386gcc-mingw-core, mingw-runtime, mingw-zlib
1387@end example
1388
1389and add some special flags to your configure invocation.
1390
1391For a static build run
1392@example
6b74787b 1393./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
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DB
1394@end example
1395
1396and for a build with shared libraries
1397@example
6b74787b 1398./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
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1399@end example
1400
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1401@section BeOS
1402
1403The configure script should guess the configuration itself.
1404Networking support is currently not finished.
1405errno issues fixed by Andrew Bachmann.
1406
1407Old stuff:
1408
7dd611c9 1409François Revol - revol at free dot fr - April 2002
47d944d2 1410
115329f1 1411The configure script should guess the configuration itself,
ce10ff8e 1412however I still did not test building on the net_server version of BeOS.
47d944d2 1413
4c5f7207 1414FFserver is broken (needs poll() implementation).
47d944d2 1415
4c5f7207 1416There are still issues with errno codes, which are negative in BeOS, and
115329f1 1417that FFmpeg negates when returning. This ends up turning errors into
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1418valid results, then crashes.
1419(To be fixed)
1420
34d7008d 1421@chapter Developers Guide
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1422
1423@section API
a0b72f90 1424@itemize @bullet
9181577c 1425@item libavcodec is the library containing the codecs (both encoding and
4c5f7207 1426decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
9181577c 1427
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1428@item libavformat is the library containing the file format handling (mux and
1429demux code for several formats). Look at @file{ffplay.c} to use it in a
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1430player. See @file{output_example.c} to use it to generate audio or video
1431streams.
1432
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1433@end itemize
1434
1435@section Integrating libavcodec or libavformat in your program
1436
1437You can integrate all the source code of the libraries to link them
1438statically to avoid any version problem. All you need is to provide a
1439'config.mak' and a 'config.h' in the parent directory. See the defines
1440generated by ./configure to understand what is needed.
1441
1442You can use libavcodec or libavformat in your commercial program, but
1443@emph{any patch you make must be published}. The best way to proceed is
4c5f7207 1444to send your patches to the FFmpeg mailing list.
9181577c 1445
80d1c272 1446@node Coding Rules
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1447@section Coding Rules
1448
4c5f7207 1449FFmpeg is programmed in the ISO C90 language with a few additional
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1450features from ISO C99, namely:
1451@itemize @bullet
1452@item
1453the @samp{inline} keyword;
1454@item
1455@samp{//} comments;
1456@item
1457designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
1458@item
114afa9c 1459compound literals (@samp{x = (struct s) @{ 17, 23 @};})
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1460@end itemize
1461
ce10ff8e
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1462These features are supported by all compilers we care about, so we will not
1463accept patches to remove their use unless they absolutely do not impair
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1464clarity and performance.
1465
4c5f7207 1466All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
cb6e87c1
FH
1467compiles with several other compilers, such as the Compaq ccc compiler
1468or Sun Studio 9, and we would like to keep it that way unless it would
ce10ff8e 1469be exceedingly involved. To ensure compatibility, please do not use any
4c5f7207 1470additional C99 features or GCC extensions. Especially watch out for:
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1471@itemize @bullet
1472@item
1473mixing statements and declarations;
1474@item
1475@samp{long long} (use @samp{int64_t} instead);
1476@item
1477@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
1478@item
019c8838 1479GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
cb6e87c1 1480@end itemize
9181577c 1481
53862e0f 1482Indent size is 4.
b86e38a0 1483The presentation is the one specified by 'indent -i4 -kr -nut'.
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1484The TAB character is forbidden outside of Makefiles as is any
1485form of trailing whitespace. Commits containing either will be
1c1b5a40 1486rejected by the Subversion repository.
9181577c 1487
4c5f7207 1488Main priority in FFmpeg is simplicity and small code size (=less
9181577c
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1489bugs).
1490
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1491Comments: Use the JavaDoc/Doxygen
1492format (see examples below) so that code documentation
1493can be generated automatically. All nontrivial functions should have a comment
ce10ff8e 1494above them explaining what the function does, even if it is just one sentence.
4c5f7207 1495All structures and their member variables should be documented, too.
f4888b83
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1496@example
1497/**
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1498 * @@file mpeg.c
1499 * MPEG codec.
1500 * @@author ...
1501 */
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1502
1503/**
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1504 * Summary sentence.
1505 * more text ...
1506 * ...
1507 */
114afa9c 1508typedef struct Foobar@{
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1509 int var1; /**< var1 description */
1510 int var2; ///< var2 description
1511 /** var3 description */
1512 int var3;
114afa9c 1513@} Foobar;
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1514
1515/**
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1516 * Summary sentence.
1517 * more text ...
1518 * ...
1519 * @@param my_parameter description of my_parameter
1520 * @@return return value description
1521 */
f4888b83
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1522int myfunc(int my_parameter)
1523...
1524@end example
9181577c 1525
115329f1 1526fprintf and printf are forbidden in libavformat and libavcodec,
36d9b4e8
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1527please use av_log() instead.
1528
1c1b5a40 1529@section Development Policy
7a57b90c
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1530
1531@enumerate
115329f1 1532@item
7a57b90c 1533 You must not commit code which breaks FFmpeg! (Meaning unfinished but
4c5f7207 1534 enabled code which breaks compilation or compiles but does not work or
7a57b90c
MN
1535 breaks the regression tests)
1536 You can commit unfinished stuff (for testing etc), but it must be disabled
1537 (#ifdef etc) by default so it does not interfere with other developers'
1538 work.
115329f1 1539@item
ce10ff8e 1540 You do not have to over-test things. If it works for you, and you think it
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DB
1541 should work for others, then commit. If your code has problems
1542 (portability, triggers compiler bugs, unusual environment etc) they will be
7a57b90c 1543 reported and eventually fixed.
115329f1 1544@item
7a57b90c 1545 Do not commit unrelated changes together, split them into self-contained
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DB
1546 pieces. Also do not forget that if part B depends on part A, but A does not
1547 depend on B, then A can and should be committed first and separate from B.
1548 Keeping changes well split into self-contained parts makes reviewing and
1549 understanding them on the commit log mailing list easier. This also helps
1550 in case of debugging later on.
1551 Also if you have doubts about splitting or not splitting, do not hesitate to
442d1598 1552 ask/discuss it on the developer mailing list.
7a57b90c
MN
1553@item
1554 Do not change behavior of the program (renaming options etc) without
019c8838 1555 first discussing it on the ffmpeg-devel mailing list. Do not remove
7a57b90c 1556 functionality from the code. Just improve!
115329f1 1557
4c5f7207 1558 Note: Redundant code can be removed.
7a57b90c
MN
1559@item
1560 Do not commit changes to the build system (Makefiles, configure script)
019c8838 1561 which change behavior, defaults etc, without asking first. The same
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1562 applies to compiler warning fixes, trivial looking fixes and to code
1563 maintained by other developers. We usually have a reason for doing things
019c8838 1564 the way we do. Send your changes as patches to the ffmpeg-devel mailing
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1565 list, and if the code maintainers say OK, you may commit. This does not
1566 apply to files you wrote and/or maintain.
1567@item
1568 We refuse source indentation and other cosmetic changes if they are mixed
1569 with functional changes, such commits will be rejected and removed. Every
1570 developer has his own indentation style, you should not change it. Of course
1571 if you (re)write something, you can use your own style, even though we would
4c5f7207 1572 prefer if the indentation throughout FFmpeg was consistent (Many projects
ce10ff8e 1573 force a given indentation style - we do not.). If you really need to make
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1574 indentation changes (try to avoid this), separate them strictly from real
1575 changes.
1576
114afa9c 1577 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
ce10ff8e 1578 then either do NOT change the indentation of the inner part within (do not
019c8838 1579 move it to the right)! or do so in a separate commit
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1580@item
1581 Always fill out the commit log message. Describe in a few lines what you
1582 changed and why. You can refer to mailing list postings if you fix a
1583 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1584@item
1585 If you apply a patch by someone else, include the name and email address in
1c1b5a40 1586 the log message. Since the ffmpeg-cvslog mailing list is publicly
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1587 archived you should add some SPAM protection to the email address. Send an
1588 answer to ffmpeg-devel (or wherever you got the patch from) saying that
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1589 you applied the patch.
1590@item
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1591 When applying patches that have been discussed (at length) on the mailing
1592 list, reference the thread in the log message.
1593@item
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1594 Do NOT commit to code actively maintained by others without permission.
1595 Send a patch to ffmpeg-devel instead. If noone answers within a reasonable
1596 timeframe (12h for build failures and security fixes, 3 days small changes,
ce10ff8e 1597 1 week for big patches) then commit your patch if you think it is OK.
5ab0f204 1598 Also note, the maintainer can simply ask for more time to review!
7a57b90c 1599@item
1c1b5a40 1600 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
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1601 are sent there and reviewed by all the other developers. Bugs and possible
1602 improvements or general questions regarding commits are discussed there. We
1603 expect you to react if problems with your code are uncovered.
1604@item
1605 Update the documentation if you change behavior or add features. If you are
019c8838 1606 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
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1607 maintainer(s) will review and commit your stuff.
1608@item
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1609 Try to keep important discussions and requests (also) on the public
1610 developer mailing list, so that all developers can benefit from them.
1611@item
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1612 Never write to unallocated memory, never write over the end of arrays,
1613 always check values read from some untrusted source before using them
1614 as array index or other risky things.
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1615@item
1616 Remember to check if you need to bump versions for the specific libav
f0efbde7 1617 parts (libavutil, libavcodec, libavformat) you are changing. You need
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1618 to change the version integer and the version string.
1619 Incrementing the first component means no backward compatibility to
a940b428 1620 previous versions (e.g. removal of a function from the public API).
76bec1d8 1621 Incrementing the second component means backward compatible change
a940b428 1622 (e.g. addition of a function to the public API).
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1623 Incrementing the third component means a noteworthy binary compatible
1624 change (e.g. encoder bug fix that matters for the decoder).
ebd32fd7 1625@item
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1626 If you add a new codec, remember to update the changelog, add it to
1627 the supported codecs table in the documentation and bump the second
1628 component of the @file{libavcodec} version number appropriately. If
1629 it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
1630 is only a decoder.
65d0bea8 1631@item
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1632 Do not change code to hide warnings without ensuring that the underlying
1633 logic is correct and thus the warning was inappropriate.
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1634@item
1635 If you add a new file, give it a proper license header. Do not copy and
1636 paste it from a random place, use an existing file as template.
114afa9c 1637@end enumerate
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1638
1639We think our rules are not too hard. If you have comments, contact us.
1640
1641Note, these rules are mostly borrowed from the MPlayer project.
1642
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1643@section Submitting patches
1644
ce10ff8e 1645First, (@pxref{Coding Rules}) above if you did not yet.
80d1c272 1646
6a6810b1 1647When you submit your patch, try to send a unified diff (diff '-up'
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1648option). I cannot read other diffs :-)
1649
6e5c1877 1650Also please do not submit patches which contain several unrelated changes.
115329f1 1651Split them into individual self-contained patches; this makes reviewing
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1652them much easier.
1653
9181577c 1654Run the regression tests before submitting a patch so that you can
6bf40f39 1655verify that there are no big problems.
9181577c 1656
9181577c 1657Patches should be posted as base64 encoded attachments (or any other
ce10ff8e 1658encoding which ensures that the patch will not be trashed during
115329f1 1659transmission) to the ffmpeg-devel mailing list, see
2b165e29 1660@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
9181577c 1661
54fcf429 1662It also helps quite a bit if you tell us what the patch does (for example
4c5f7207 1663'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
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1664and has no lrint()')
1665
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1666Also please if you send several patches, send each patch as separate mail,
1667do not attach several unrelated patches to the same mail.
a15bcf70 1668
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1669@section patch submission checklist
1670
1671@enumerate
1672@item
1673 Do the regression tests pass with the patch applied?
1674@item
1675 Is the patch a unified diff?
1676@item
4a7a0908 1677 Is the patch against latest FFmpeg SVN?
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1678@item
1679 Are you subscribed to ffmpeg-dev?
1680 (the list is subscribers only due to spam)
1681@item
1682 Have you checked that the changes are minimal, so that the same cannot be
442d1598 1683 achieved with a smaller patch and/or simpler final code?
dd597cd7 1684@item
4a7a0908 1685 If the change is to speed critical code, did you benchmark it?
dd597cd7 1686@item
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1687 If you did any benchmarks, did you provide them in the mail?
1688@item
442d1598 1689 Have you checked that the patch does not introduce buffer overflows or
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1690 other security issues?
1691@item
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1692 Is the patch created from the root of the source tree, so it can be
1693 applied with @code{patch -p0}?
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1694@item
1695 Does the patch not mix functional and cosmetic changes?
1696@item
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1697 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1698@item
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1699 Is the patch attached to the email you send?
1700@item
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1701 Is the mime type of the patch correct? It should be text/x-diff or
1702 text/x-patch or at least text/plain and not application/octet-stream.
dd597cd7 1703@item
4a7a0908 1704 If the patch fixes a bug, did you provide a verbose analysis of the bug?
dd597cd7 1705@item
4a7a0908 1706 If the patch fixes a bug, did you provide enough information, including
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1707 a sample, so the bug can be reproduced and the fix can be verified?
1708@item
1709 Did you provide a verbose summary about what the patch does change?
1710@item
1711 Did you provide a verbose explanation why it changes things like it does?
1712@item
442d1598 1713 Did you provide a verbose summary of the user visible advantages and
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1714 disadvantages if the patch is applied?
1715@item
1716 Did you provide an example so we can verify the new feature added by the
1717 patch easily?
1718@item
bbe94afb 1719 If you added a new file, did you insert a license header? It should be
6baa2943 1720 taken from FFmpeg, not randomly copied and pasted from somewhere else.
6e4bc6ee 1721@item
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1722 You should maintain alphabetical order in alphabetically ordered lists as
1723 long as doing so does not break API/ABI compatibility.
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1724@item
1725 Did you provide a suggestion for a clear commit log message?
dd597cd7
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1726@end enumerate
1727
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1728@section Patch review process
1729
1730All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1731clear note that the patch is not for SVN.
1732Reviews and comments will be posted as replies to the patch on the
ce10ff8e 1733mailing list. The patch submitter then has to take care of every comment,
442d1598 1734that can be by resubmitting a changed patch or by discussion. Resubmitted
ce10ff8e 1735patches will themselves be reviewed like any other patch. If at some point
f5f11d71 1736a patch passes review with no comments then it is approved, that can for
ce10ff8e 1737simple and small patches happen immediately while large patches will generally
f5f11d71 1738have to be changed and reviewed many times before they are approved.
ce10ff8e 1739After a patch is approved it will be committed to the repository.
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1740
1741We will review all submitted patches, but sometimes we are quite busy so
1742especially for large patches this can take several weeks.
1743
1744When resubmitting patches, please do not make any significant changes
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1745not related to the comments received during review. Such patches will
1746be rejected. Instead, submit significant changes or new features as
1747separate patches.
cf7f2b16 1748
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1749@section Regression tests
1750
1c1b5a40 1751Before submitting a patch (or committing to the repository), you should at least
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1752test that you did not break anything.
1753
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1754The regression tests build a synthetic video stream and a synthetic
1755audio stream. These are then encoded and decoded with all codecs or
9181577c 1756formats. The CRC (or MD5) of each generated file is recorded in a
4c5f7207 1757result file. A 'diff' is launched to compare the reference results and
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1758the result file.
1759
4c5f7207 1760The regression tests then go on to test the FFserver code with a
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1761limited set of streams. It is important that this step runs correctly
1762as well.
1763
36d9b4e8 1764Run 'make test' to test all the codecs and formats.
9181577c 1765
4c5f7207 1766Run 'make fulltest' to test all the codecs, formats and FFserver.
9181577c 1767
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1768[Of course, some patches may change the results of the regression tests. In
1769this case, the reference results of the regression tests shall be modified
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1770accordingly].
1771
1772@bye