updates the x11grab doc example, adding -s cif, as it is mandatory
[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 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}.
18bff752 588@item -vhook module
4c5f7207 589Insert video processing @var{module}. @var{module} contains the module
18bff752 590name and its parameters separated by spaces.
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591@item -top n
592top=1/bottom=0/auto=-1 field first
593@item -dc precision
594Intra_dc_precision.
595@item -vtag fourcc/tag
596Force video tag/fourcc.
597@item -qphist
598Show QP histogram.
599@item -vbsf bitstream filter
600Bitstream filters available are "dump_extra", "remove_extra", "noise".
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601@end table
602
603@section Audio Options
604
605@table @option
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606@item -aframes number
607Set the number of audio frames to record.
115329f1 608@item -ar freq
4c5f7207 609Set the audio sampling frequency (default = 44100 Hz).
115329f1 610@item -ab bitrate
5438308f 611Set the audio bitrate in bit/s (default = 64k).
18bff752 612@item -ac channels
4c5f7207 613Set the number of audio channels (default = 1).
5ee03c86 614@item -an
4c5f7207 615Disable audio recording.
5ee03c86 616@item -acodec codec
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617Force audio codec to @var{codec}. Use the @code{copy} special value to
618specify that the raw codec data must be copied as is.
de62a89d 619@item -newaudio
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620Add a new audio track to the output file. If you want to specify parameters,
621do so before @code{-newaudio} (@code{-acodec}, @code{-ab}, etc..).
de62a89d 622
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623Mapping will be done automatically, if the number of output streams is equal to
624the number of input streams, else it will pick the first one that matches. You
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625can override the mapping using @code{-map} as usual.
626
627Example:
628@example
5438308f 629ffmpeg -i file.mpg -vcodec copy -acodec ac3 -ab 384k test.mpg -acodec mp2 -ab 192k -newaudio
de62a89d 630@end example
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631@item -alang code
632Set the ISO 639 language code (3 letters) of the current audio stream.
633@end table
634
635@section Advanced Audio options:
636
637@table @option
638@item -atag fourcc/tag
639Force audio tag/fourcc.
640@item -absf bitstream filter
641Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp".
642@end table
643
644@section Subtitle options:
645
646@table @option
647@item -scodec codec
648Force subtitle codec ('copy' to copy stream).
649@item -newsubtitle
650Add a new subtitle stream to the current output stream.
651@item -slang code
652Set the ISO 639 language code (3 letters) of the current subtitle stream.
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653@end table
654
655@section Audio/Video grab options
656
657@table @option
18bff752 658@item -vc channel
4c5f7207 659Set video grab channel (DV1394 only).
18bff752 660@item -tvstd standard
4c5f7207 661Set television standard (NTSC, PAL (SECAM)).
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662@item -isync
663Synchronize read on input.
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664@end table
665
666@section Advanced options
667
668@table @option
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669@item -map input stream id[:input stream id]
670Set stream mapping from input streams to output streams.
671Just enumerate the input streams in the order you want them in the output.
672[input stream id] sets the (input) stream to sync against.
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673@item -map_meta_data outfile:infile
674Set meta data information of outfile from infile.
18bff752 675@item -debug
4c5f7207 676Print specific debug info.
115329f1 677@item -benchmark
4c5f7207 678Add timings for benchmarking.
4386f941 679@item -dump
4c5f7207 680Dump each input packet.
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681@item -hex
682When dumping packets, also dump the payload.
18bff752 683@item -bitexact
4c5f7207 684Only use bit exact algorithms (for codec testing).
18bff752 685@item -ps size
4c5f7207 686Set packet size in bits.
5ee03c86 687@item -re
4c5f7207 688Read input at native frame rate. Mainly used to simulate a grab device.
4386f941 689@item -loop_input
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690Loop over the input stream. Currently it works only for image
691streams. This option is used for automatic FFserver testing.
8108551a 692@item -loop_output number_of_times
019c8838 693Repeatedly loop output for formats that support looping such as animated GIF
4c5f7207 694(0 will loop the output infinitely).
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695@item -threads count
696Thread count.
c52e13f1 697@item -vsync parameter
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698Video sync method. Video will be stretched/squeezed to match the timestamps,
699it is done by duplicating and dropping frames. With -map you can select from
700which stream the timestamps should be taken. You can leave either video or
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701audio unchanged and sync the remaining stream(s) to the unchanged one.
702@item -async samples_per_second
29c9183c 703Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
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704the parameter is the maximum samples per second by which the audio is changed.
705-async 1 is a special case where only the start of the audio stream is corrected
706without any later correction.
9181577c 707@end table
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708
709@node FFmpeg formula evaluator
710@section FFmpeg formula evaluator
711
712When evaluating a rate control string, FFmpeg uses an internal formula
115329f1 713evaluator.
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714
715The following binary operators are available: @code{+}, @code{-},
716@code{*}, @code{/}, @code{^}.
717
718The following unary operators are available: @code{+}, @code{-},
719@code{(...)}.
720
721The following functions are available:
722@table @var
723@item sinh(x)
724@item cosh(x)
725@item tanh(x)
726@item sin(x)
727@item cos(x)
728@item tan(x)
729@item exp(x)
730@item log(x)
731@item squish(x)
732@item gauss(x)
733@item abs(x)
734@item max(x, y)
735@item min(x, y)
736@item gt(x, y)
737@item lt(x, y)
738@item eq(x, y)
739@item bits2qp(bits)
740@item qp2bits(qp)
741@end table
742
743The following constants are available:
744@table @var
745@item PI
746@item E
747@item iTex
748@item pTex
749@item tex
750@item mv
751@item fCode
752@item iCount
753@item mcVar
754@item var
755@item isI
756@item isP
757@item isB
758@item avgQP
759@item qComp
760@item avgIITex
761@item avgPITex
762@item avgPPTex
763@item avgBPTex
764@item avgTex
765@end table
766
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767@c man end
768
769@ignore
770
771@setfilename ffmpeg
772@settitle FFmpeg video converter
773
774@c man begin SEEALSO
019c8838 775ffserver(1), ffplay(1) and the HTML documentation of @file{ffmpeg}.
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776@c man end
777
778@c man begin AUTHOR
779Fabrice Bellard
780@c man end
781
782@end ignore
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783
784@section Protocols
785
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786The filename can be @file{-} to read from standard input or to write
787to standard output.
9181577c 788
4c5f7207 789FFmpeg also handles many protocols specified with an URL syntax.
9181577c 790
4c5f7207 791Use 'ffmpeg -formats' to see a list of the supported protocols.
9181577c 792
e99c4e10 793The protocol @code{http:} is currently used only to communicate with
4c5f7207 794FFserver (see the FFserver documentation). When FFmpeg will be a
e99c4e10 795video player it will also be used for streaming :-)
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796
797@chapter Tips
798
799@itemize
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800@item For streaming at very low bitrate application, use a low frame rate
801and a small GOP size. This is especially true for RealVideo where
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802the Linux player does not seem to be very fast, so it can miss
803frames. An example is:
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804
805@example
3c0ba870 806ffmpeg -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
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807@end example
808
809@item The parameter 'q' which is displayed while encoding is the current
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810quantizer. The value 1 indicates that a very good quality could
811be achieved. The value 31 indicates the worst quality. If q=31 appears
e99c4e10 812too often, it means that the encoder cannot compress enough to meet
4c5f7207 813your bitrate. You must either increase the bitrate, decrease the
e99c4e10 814frame rate or decrease the frame size.
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815
816@item If your computer is not fast enough, you can speed up the
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817compression at the expense of the compression ratio. You can use
818'-me zero' to speed up motion estimation, and '-intra' to disable
4c5f7207 819motion estimation completely (you have only I-frames, which means it
e99c4e10 820is about as good as JPEG compression).
9181577c 821
4c5f7207 822@item To have very low audio bitrates, reduce the sampling frequency
019c8838 823(down to 22050 kHz for MPEG audio, 22050 or 11025 for AC3).
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824
825@item To have a constant quality (but a variable bitrate), use the option
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826'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
827quality).
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828
829@item When converting video files, you can use the '-sameq' option which
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830uses the same quality factor in the encoder as in the decoder.
831It allows almost lossless encoding.
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832
833@end itemize
834
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835
836@chapter external libraries
837
838FFmpeg can be hooked up with a number of external libraries to add support
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839for more formats. None of them are used by default, their use has to be
840explicitly requested by passing the appropriate flags to @file{./configure}.
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841
842@section AMR
843
844AMR comes in two different flavors, WB and NB. FFmpeg can make use of the
845AMR WB (floating-point mode) and the AMR NB (both floating-point and
846fixed-point mode) reference decoders and encoders.
847
848@itemize
849
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850@item For AMR WB floating-point and AMR NB floating point support, go to
851@url{http://www.penguin.cz/~utx/amr} and follow the instructions for building
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852the libraries. Pass @code{--enable-amr-nb} and/or @code{--enable-amr-wb} to
853configure to enable the libraries.
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854
855@item For AMR NB fixed-point download TS26.073 REL-6 V6.0.0 from
856@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.073/26073-600.zip}
857and extract the source to the directory @file{libavcodec/amr}.
ef4e31d4 858You must also add @code{-DMMS_IO} to @code{CFLAGS} in
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859@file{libavcodec/amr/makefile}, i.e.
860``@code{CFLAGS = -Wall -pedantic-errors -I. $(CFLAGS_$(MODE)) -D$(VAD) -DMMS_IO}''.
4f99f932 861Pass @code{--enable-amr-nb-fixed} to configure to enable it.
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862
863@end itemize
864
865
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866@chapter Supported File Formats and Codecs
867
868You can use the @code{-formats} option to have an exhaustive list.
869
870@section File Formats
871
6bf40f39 872FFmpeg supports the following file formats through the @code{libavformat}
0699d2fe 873library:
9181577c 874
3fc9e78f 875@multitable @columnfractions .4 .1 .1 .4
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876@item Supported File Format @tab Encoding @tab Decoding @tab Comments
877@item MPEG audio @tab X @tab X
4c5f7207 878@item MPEG-1 systems @tab X @tab X
9181577c 879@tab muxed audio and video
4c5f7207 880@item MPEG-2 PS @tab X @tab X
9181577c 881@tab also known as @code{VOB} file
4c5f7207 882@item MPEG-2 TS @tab @tab X
9181577c 883@tab also known as DVB Transport Stream
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884@item ASF@tab X @tab X
885@item AVI@tab X @tab X
886@item WAV@tab X @tab X
9181577c 887@item Macromedia Flash@tab X @tab X
4c5f7207 888@tab Only embedded audio is decoded.
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889@item FLV @tab X @tab X
890@tab Macromedia Flash video files
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891@item Real Audio and Video @tab X @tab X
892@item Raw AC3 @tab X @tab X
893@item Raw MJPEG @tab X @tab X
894@item Raw MPEG video @tab X @tab X
895@item Raw PCM8/16 bits, mulaw/Alaw@tab X @tab X
896@item Raw CRI ADX audio @tab X @tab X
897@item Raw Shorten audio @tab @tab X
898@item SUN AU format @tab X @tab X
7fe4c823 899@item NUT @tab X @tab X @tab NUT Open Container Format
115329f1 900@item QuickTime @tab X @tab X
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901@item MPEG-4 @tab X @tab X
902@tab MPEG-4 is a variant of QuickTime.
115329f1 903@item Raw MPEG4 video @tab X @tab X
4fa1c4fa 904@item DV @tab X @tab X
701b603d 905@item 4xm @tab @tab X
4c5f7207 906@tab 4X Technologies format, used in some games.
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907@item Playstation STR @tab @tab X
908@item Id RoQ @tab @tab X
4c5f7207 909@tab Used in Quake III, Jedi Knight 2, other computer games.
4d3b1f8d 910@item Interplay MVE @tab @tab X
4c5f7207 911@tab Format used in various Interplay computer games.
b17e9c99 912@item WC3 Movie @tab @tab X
4c5f7207 913@tab Multimedia format used in Origin's Wing Commander III computer game.
2fdf638b 914@item Sega FILM/CPK @tab @tab X
4c5f7207 915@tab Used in many Sega Saturn console games.
2fdf638b 916@item Westwood Studios VQA/AUD @tab @tab X
4c5f7207 917@tab Multimedia formats used in Westwood Studios games.
4120a53a 918@item Id Cinematic (.cin) @tab @tab X
4c5f7207 919@tab Used in Quake II.
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920@item FLIC format @tab @tab X
921@tab .fli/.flc files
da00f30e 922@item Sierra VMD @tab @tab X
4c5f7207 923@tab Used in Sierra CD-ROM games.
d08d7142 924@item Sierra Online @tab @tab X
4c5f7207 925@tab .sol files used in Sierra Online games.
38088adf 926@item Matroska @tab @tab X
ad81a9fe 927@item Electronic Arts Multimedia @tab @tab X
4c5f7207 928@tab Used in various EA games; files have extensions like WVE and UV2.
353147ed 929@item Nullsoft Video (NSV) format @tab @tab X
4accd1fd 930@item ADTS AAC audio @tab X @tab X
ea395e8c 931@item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro.
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932@item American Laser Games MM @tab @tab X
933@tab Multimedia format used in games like Mad Dog McCree
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934@item AVS @tab @tab X
935@tab Multimedia format used by the Creature Shock game.
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936@item Smacker @tab @tab X
937@tab Multimedia format used by many games.
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938@item GXF @tab X @tab X
939@tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.
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940@item CIN @tab @tab X
941@tab Multimedia format used by Delphine Software games.
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942@item MXF @tab @tab X
943@tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
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944@item SEQ @tab @tab X
945@tab Tiertex .seq files used in the DOS CDROM version of the game Flashback.
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946@item DXA @tab @tab X
947@tab This format is used in non-Windows version of Feeble Files game and
948different game cutscenes repacked for use with ScummVM.
efb0c399 949@item THP @tab @tab X
d1e0d21f 950@tab Used on the Nintendo GameCube.
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951@item C93 @tab @tab X
952@tab Used in the game Cyberia from Interplay.
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953@item Bethsoft VID @tab @tab X
954@tab Used in some games from Bethesda Softworks.
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955@item CRYO APC @tab @tab X
956@tab Audio format used in some games by CRYO Interactive Entertainment.
353147ed 957@end multitable
9181577c 958
4c5f7207 959@code{X} means that encoding (resp. decoding) is supported.
9181577c 960
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961@section Image Formats
962
963FFmpeg can read and write images for each frame of a video sequence. The
964following image formats are supported:
965
3fc9e78f 966@multitable @columnfractions .4 .1 .1 .4
0699d2fe 967@item Supported Image Format @tab Encoding @tab Decoding @tab Comments
115329f1 968@item PGM, PPM @tab X @tab X
4c5f7207 969@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
2eb5d024 970@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
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971@item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
972@item .Y.U.V @tab X @tab X @tab one raw file per component
973@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
974@item PNG @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
3689cf16 975@item Targa @tab @tab X @tab Targa (.TGA) image format.
716222db 976@item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
6a91ec51 977@item SGI @tab X @tab X @tab SGI RGB image format
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978@end multitable
979
4c5f7207 980@code{X} means that encoding (resp. decoding) is supported.
0699d2fe 981
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982@section Video Codecs
983
3fc9e78f 984@multitable @columnfractions .4 .1 .1 .4
9181577c 985@item Supported Codec @tab Encoding @tab Decoding @tab Comments
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986@item MPEG-1 video @tab X @tab X
987@item MPEG-2 video @tab X @tab X
2bc5da7b 988@item MPEG-4 @tab X @tab X
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989@item MSMPEG4 V1 @tab X @tab X
990@item MSMPEG4 V2 @tab X @tab X
2bc5da7b 991@item MSMPEG4 V3 @tab X @tab X
9181577c 992@item WMV7 @tab X @tab X
4c5f7207 993@item WMV8 @tab X @tab X @tab not completely working
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994@item WMV9 @tab @tab X @tab not completely working
995@item VC1 @tab @tab X
b06b45c4 996@item H.261 @tab X @tab X
4c5f7207 997@item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0
b06b45c4 998@item H.264 @tab @tab X
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999@item RealVideo 1.0 @tab X @tab X
1000@item RealVideo 2.0 @tab X @tab X
115329f1 1001@item MJPEG @tab X @tab X
4c5f7207 1002@item lossless MJPEG @tab X @tab X
26d6d032 1003@item JPEG-LS @tab X @tab X @tab fourcc: MJLS, lossless and near-lossless is supported
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1004@item Apple MJPEG-B @tab @tab X
1005@item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X
115329f1 1006@item DV @tab X @tab X
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1007@item HuffYUV @tab X @tab X
1008@item FFmpeg Video 1 @tab X @tab X @tab experimental lossless codec (fourcc: FFV1)
1009@item FFmpeg Snow @tab X @tab X @tab experimental wavelet codec (fourcc: SNOW)
701b603d 1010@item Asus v1 @tab X @tab X @tab fourcc: ASV1
4d3b1f8d 1011@item Asus v2 @tab X @tab X @tab fourcc: ASV2
701b603d 1012@item Creative YUV @tab @tab X @tab fourcc: CYUV
d2bfadc0 1013@item Sorenson Video 1 @tab X @tab X @tab fourcc: SVQ1
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1014@item Sorenson Video 3 @tab @tab X @tab fourcc: SVQ3
1015@item On2 VP3 @tab @tab X @tab still experimental
5ce117c3 1016@item On2 VP5 @tab @tab X @tab fourcc: VP50
9110a0e3 1017@item On2 VP6 @tab @tab X @tab fourcc: VP60,VP61,VP62
150d2772 1018@item Theora @tab X @tab X @tab still experimental
cdb2c1ca 1019@item Intel Indeo 3 @tab @tab X
9303d49c 1020@item FLV @tab X @tab X @tab Sorenson H.263 used in Flash
15419468 1021@item Flash Screen Video @tab X @tab X @tab fourcc: FSV1
4d3b1f8d 1022@item ATI VCR1 @tab @tab X @tab fourcc: VCR1
7fe4c823 1023@item ATI VCR2 @tab @tab X @tab fourcc: VCR2
4d3b1f8d 1024@item Cirrus Logic AccuPak @tab @tab X @tab fourcc: CLJR
4c5f7207 1025@item 4X Video @tab @tab X @tab Used in certain computer games.
115329f1 1026@item Sony Playstation MDEC @tab @tab X
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1027@item Id RoQ @tab @tab X @tab Used in Quake III, Jedi Knight 2, other computer games.
1028@item Xan/WC3 @tab @tab X @tab Used in Wing Commander III .MVE files.
1029@item Interplay Video @tab @tab X @tab Used in Interplay .MVE files.
070ed1bc 1030@item Apple Animation @tab @tab X @tab fourcc: 'rle '
42cad81a 1031@item Apple Graphics @tab @tab X @tab fourcc: 'smc '
2fdf638b 1032@item Apple Video @tab @tab X @tab fourcc: rpza
d08d7142 1033@item Apple QuickDraw @tab @tab X @tab fourcc: qdrw
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1034@item Cinepak @tab @tab X
1035@item Microsoft RLE @tab @tab X
1036@item Microsoft Video-1 @tab @tab X
4120a53a 1037@item Westwood VQA @tab @tab X
4c5f7207 1038@item Id Cinematic Video @tab @tab X @tab Used in Quake II.
1dc1ed99 1039@item Planar RGB @tab @tab X @tab fourcc: 8BPS
42cad81a 1040@item FLIC video @tab @tab X
9a4117d5 1041@item Duck TrueMotion v1 @tab @tab X @tab fourcc: DUCK
dce76c20 1042@item Duck TrueMotion v2 @tab @tab X @tab fourcc: TM20
4c5f7207 1043@item VMD Video @tab @tab X @tab Used in Sierra VMD files.
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1044@item MSZH @tab @tab X @tab Part of LCL
1045@item ZLIB @tab X @tab X @tab Part of LCL, encoder experimental
9d53d58e 1046@item TechSmith Camtasia @tab @tab X @tab fourcc: TSCC
d0a0bbd2 1047@item IBM Ultimotion @tab @tab X @tab fourcc: ULTI
ab711b3c 1048@item Miro VideoXL @tab @tab X @tab fourcc: VIXL
acfd8f0f 1049@item QPEG @tab @tab X @tab fourccs: QPEG, Q1.0, Q1.1
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1050@item LOCO @tab @tab X @tab
1051@item Winnov WNV1 @tab @tab X @tab
589f8220 1052@item Autodesk Animator Studio Codec @tab @tab X @tab fourcc: AASC
115329f1 1053@item Fraps FPS1 @tab @tab X @tab
2b6c1d80 1054@item CamStudio @tab @tab X @tab fourcc: CSCD
4e114829 1055@item American Laser Games Video @tab @tab X @tab Used in games like Mad Dog McCree
f48d6e1b 1056@item ZMBV @tab X @tab X @tab Encoder works only on PAL8
26376701 1057@item AVS Video @tab @tab X @tab Video encoding used by the Creature Shock game.
348efc18 1058@item Smacker Video @tab @tab X @tab Video encoding used in Smacker.
dfca23e3 1059@item RTjpeg @tab @tab X @tab Video encoding used in NuppelVideo files.
fd7b1991 1060@item KMVC @tab @tab X @tab Codec used in Worms games.
eb57c889 1061@item VMware Video @tab @tab X @tab Codec used in videos captured by VMware.
dc56e0de 1062@item Cin Video @tab @tab X @tab Codec used in Delphine Software games.
29f86228 1063@item Tiertex Seq Video @tab @tab X @tab Codec used in DOS CDROM FlashBack game.
33a0dd37 1064@item DXA Video @tab @tab X @tab Codec originally used in Feeble Files game.
52b6bad2 1065@item AVID DNxHD @tab @tab X @tab aka SMPTE VC3
9a0ddd09 1066@item C93 Video @tab @tab X @tab Codec used in Cyberia game.
8845202e 1067@item THP @tab @tab X @tab Used on the Nintendo GameCube.
1e6c6759 1068@item Bethsoft VID @tab @tab X @tab Used in some games from Bethesda Softworks.
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1069@end multitable
1070
4c5f7207 1071@code{X} means that encoding (resp. decoding) is supported.
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1072
1073@section Audio Codecs
1074
1075@multitable @columnfractions .4 .1 .1 .1 .7
1076@item Supported Codec @tab Encoding @tab Decoding @tab Comments
115329f1 1077@item MPEG audio layer 2 @tab IX @tab IX
9181577c 1078@item MPEG audio layer 1/3 @tab IX @tab IX
4c5f7207 1079@tab MP3 encoding is supported through the external library LAME.
37776c3b 1080@item AC3 @tab IX @tab IX
4c5f7207 1081@tab liba52 is used internally for decoding.
34d7008d 1082@item Vorbis @tab X @tab X
74882049 1083@item WMA V1/V2 @tab X @tab X
f6fa7a6c 1084@item AAC @tab X @tab X
4c5f7207 1085@tab Supported through the external library libfaac/libfaad.
d4c3c5a6 1086@item Microsoft ADPCM @tab X @tab X
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1087@item MS IMA ADPCM @tab X @tab X
1088@item QT IMA ADPCM @tab @tab X
1089@item 4X IMA ADPCM @tab @tab X
d4e437df 1090@item G.726 ADPCM @tab X @tab X
b17e9c99 1091@item Duck DK3 IMA ADPCM @tab @tab X
4c5f7207 1092@tab Used in some Sega Saturn console games.
b17e9c99 1093@item Duck DK4 IMA ADPCM @tab @tab X
4c5f7207 1094@tab Used in some Sega Saturn console games.
2fdf638b 1095@item Westwood Studios IMA ADPCM @tab @tab X
4c5f7207 1096@tab Used in Westwood Studios games like Command and Conquer.
7d8379f2 1097@item SMJPEG IMA ADPCM @tab @tab X
4c5f7207 1098@tab Used in certain Loki game ports.
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1099@item CD-ROM XA ADPCM @tab @tab X
1100@item CRI ADX ADPCM @tab X @tab X
4c5f7207 1101@tab Used in Sega Dreamcast games.
7d8379f2 1102@item Electronic Arts ADPCM @tab @tab X
4c5f7207 1103@tab Used in various EA titles.
b3bfb299 1104@item Creative ADPCM @tab @tab X
2433f24f 1105@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
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1106@item THP ADPCM @tab @tab X
1107@tab Used on the Nintendo GameCube.
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1108@item RA144 @tab @tab X
1109@tab Real 14400 bit/s codec
1110@item RA288 @tab @tab X
1111@tab Real 28800 bit/s codec
37776c3b 1112@item RADnet @tab X @tab IX
4c5f7207 1113@tab Real low bitrate AC3 codec, liba52 is used for decoding.
2eb5d024 1114@item AMR-NB @tab X @tab X
4c5f7207 1115@tab Supported through an external library.
d663a1fd 1116@item AMR-WB @tab X @tab X
4c5f7207 1117@tab Supported through an external library.
2eb5d024 1118@item DV audio @tab @tab X
4d3b1f8d 1119@item Id RoQ DPCM @tab @tab X
4c5f7207 1120@tab Used in Quake III, Jedi Knight 2, other computer games.
4d3b1f8d 1121@item Interplay MVE DPCM @tab @tab X
4c5f7207 1122@tab Used in various Interplay computer games.
b17e9c99 1123@item Xan DPCM @tab @tab X
4c5f7207 1124@tab Used in Origin's Wing Commander IV AVI files.
d08d7142 1125@item Sierra Online DPCM @tab @tab X
4c5f7207 1126@tab Used in Sierra Online game audio files.
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1127@item Apple MACE 3 @tab @tab X
1128@item Apple MACE 6 @tab @tab X
bfd9a00f 1129@item FLAC lossless audio @tab X @tab X
13dfd2b9 1130@item Shorten lossless audio @tab @tab X
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1131@item Apple lossless audio @tab @tab X
1132@tab QuickTime fourcc 'alac'
33a4d8b1 1133@item FFmpeg Sonic @tab X @tab X
4c5f7207 1134@tab experimental lossy/lossless codec
d9b1c197
RT
1135@item Qdesign QDM2 @tab @tab X
1136@tab there are still some distortions
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1137@item Real COOK @tab @tab X
1138@tab All versions except 5.1 are supported
e839a994 1139@item DSP Group TrueSpeech @tab @tab X
3dc411c0 1140@item True Audio (TTA) @tab @tab X
348efc18 1141@item Smacker Audio @tab @tab X
730581f3 1142@item WavPack Audio @tab @tab X
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1143@item Cin Audio @tab @tab X
1144@tab Codec used in Delphine Software games.
84ed36da 1145@item Intel Music Coder @tab @tab X
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1146@item Musepack @tab @tab X
1147@tab Only SV7 is supported
01ca9ac3 1148@item DT$ Coherent Audio @tab @tab X
10e26bc7 1149@item ATRAC 3 @tab @tab X
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1150@end multitable
1151
4c5f7207 1152@code{X} means that encoding (resp. decoding) is supported.
9181577c 1153
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1154@code{I} means that an integer-only version is available, too (ensures high
1155performance on systems without hardware floating point support).
9181577c 1156
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1157@chapter Platform Specific information
1158
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1159@section BSD
1160
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1161BSD make will not build FFmpeg, you need to install and use GNU Make
1162(@file{gmake}).
1163
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1164@section Windows
1165
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1166To get help and instructions for using FFmpeg under Windows, check out
1167the FFmpeg Windows Help Forum at
1168@url{http://arrozcru.no-ip.org/ffmpeg/}.
1169
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1170@subsection Native Windows compilation
1171
1172@itemize
1173@item Install the current versions of MSYS and MinGW from
1174@url{http://www.mingw.org/}. You can find detailed installation
1175instructions in the download section and the FAQ.
1176
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1177NOTE: Use at least bash 3.1. Older versions are known to be failing on the
1178configure script.
1179
4c5f7207 1180@item If you want to test the FFplay, also download
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1181the MinGW development library of SDL 1.2.x
1182(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
4c5f7207 1183@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
50f52fcd 1184unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
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1185directory. Edit the @file{sdl-config} script so that it gives the
1186correct SDL directory when invoked.
50f52fcd 1187
e926e391 1188@item Extract the current version of FFmpeg.
115329f1 1189
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1190@item Start the MSYS shell (file @file{msys.bat}).
1191
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1192@item Change to the FFmpeg directory and follow
1193 the instructions of how to compile FFmpeg (file
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1194@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
1195suffices. If you have problems using SDL, verify that
1196@file{sdl-config} can be launched from the MSYS command line.
1197
4c5f7207 1198@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
ce10ff8e 1199@file{make install}. Do not forget to copy @file{SDL.dll} to the place
4c5f7207 1200you launch @file{ffplay} from.
50f52fcd 1201
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1202@end itemize
1203
115329f1 1204Notes:
988a9f9e 1205@itemize
50f52fcd 1206
988a9f9e
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1207@item The target @file{make wininstaller} can be used to create a
1208Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
4c5f7207 1209must be copied to the FFmpeg directory in order to build the
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1210installer.
1211
4c5f7207 1212@item By using @code{./configure --enable-shared} when configuring FFmpeg,
988a9f9e
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1213you can build @file{avcodec.dll} and @file{avformat.dll}. With
1214@code{make install} you install the FFmpeg DLLs and the associated
115329f1 1215headers in @file{Program Files/FFmpeg}.
988a9f9e 1216
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1217@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
1218when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
988a9f9e 1219C++ @code{lib} tool to build @code{avcodec.lib} and
4c5f7207 1220@code{avformat.lib}. With these libraries you can link your Visual C++
be0efc0c 1221code directly with the FFmpeg DLLs (see below).
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1222
1223@end itemize
b030b284 1224
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1225@subsection Visual C++ compatibility
1226
1227FFmpeg will not compile under Visual C++ -- and it has too many
1228dependencies on the GCC compiler to make a port viable. However,
1229if you want to use the FFmpeg libraries in your own applications,
1230you can still compile those applications using Visual C++. An
1231important restriction to this is that you have to use the
1232dynamically linked versions of the FFmpeg libraries (i.e. the
1233DLLs), and you have to make sure that Visual-C++-compatible
1234import libraries are created during the FFmpeg build process.
1235
1236This description of how to use the FFmpeg libraries with Visual C++ is
1237based on Visual C++ 2005 Express Edition Beta 2. If you have a different
1238version, you might have to modify the procedures slightly.
1239
1240Here are the step-by-step instructions for building the FFmpeg libraries
1241so they can be used with Visual C++:
1242
1243@enumerate
1244
ce10ff8e 1245@item Install Visual C++ (if you have not done so already).
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1246
1247@item Install MinGW and MSYS as described above.
1248
1249@item Add a call to @file{vcvars32.bat} (which sets up the environment
1250variables for the Visual C++ tools) as the first line of
1251@file{msys.bat}. The standard location for @file{vcvars32.bat} is
1252@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
1253and the standard location for @file{msys.bat} is
1254@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
1255following line as the first line of @file{msys.bat}:
1256
1257@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
1258
1259@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
1260If you get a help message with the command line options of @code{link.exe},
1261this means your environment variables are set up correctly, the
1262Microsoft linker is on the path and will be used by FFmpeg to
1263create Visual-C++-compatible import libraries.
1264
e926e391 1265@item Extract the current version of FFmpeg and change to the FFmpeg directory.
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1266
1267@item Type the command
51d8321d 1268@code{./configure --enable-shared --disable-static --enable-memalign-hack}
ce10ff8e 1269to configure and, if that did not produce any errors,
51d8321d 1270type @code{make} to build FFmpeg.
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1271
1272@item The subdirectories @file{libavformat}, @file{libavcodec}, and
1273@file{libavutil} should now contain the files @file{avformat.dll},
1274@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
1275@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
1276DLLs to your System32 directory (typically @file{C:\Windows\System32}).
1277
1278@end enumerate
1279
1280And here is how to use these libraries with Visual C++:
1281
1282@enumerate
1283
1284@item Create a new console application ("File / New / Project") and then
1285select "Win32 Console Application". On the appropriate page of the
1286Application Wizard, uncheck the "Precompiled headers" option.
1287
1288@item Write the source code for your application, or, for testing, just
1289copy the code from an existing sample application into the source file
1290that Visual C++ has already created for you. (Note that your source
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DB
1291filehas to have a @code{.cpp} extension; otherwise, Visual C++ will not
1292compile the FFmpeg headers correctly because in C mode, it does not
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1293recognize the @code{inline} keyword.) For example, you can copy
1294@file{output_example.c} from the FFmpeg distribution (but you will
1295have to make minor modifications so the code will compile under
1296C++, see below).
1297
1298@item Open the "Project / Properties" dialog box. In the "Configuration"
1299combo box, select "All Configurations" so that the changes you make will
1300affect both debug and release builds. In the tree view on the left hand
1301side, select "C/C++ / General", then edit the "Additional Include
1302Directories" setting to contain the complete paths to the
1303@file{libavformat}, @file{libavcodec}, and @file{libavutil}
1304subdirectories of your FFmpeg directory. Note that the directories have
1305to be separated using semicolons. Now select "Linker / General" from the
1306tree view and edit the "Additional Library Directories" setting to
1307contain the same three directories.
1308
1309@item Still in the "Project / Properties" dialog box, select "Linker / Input"
1310from the tree view, then add the files @file{avformat.lib},
1311@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
1312Dependencies". Note that the names of the libraries have to be separated
1313using spaces.
1314
765c3440 1315@item Now, select "C/C++ / Code Generation" from the tree view. Select
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1316"Debug" in the "Configuration" combo box. Make sure that "Runtime
1317Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
1318the "Configuration" combo box and make sure that "Runtime Library" is
1319set to "Multi-threaded DLL".
1320
1321@item Click "OK" to close the "Project / Properties" dialog box and build
1322the application. Hopefully, it should compile and run cleanly. If you
1323used @file{output_example.c} as your sample application, you will get a
1324few compiler errors, but they are easy to fix. The first type of error
ce10ff8e 1325occurs because Visual C++ does not allow an @code{int} to be converted to
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1326an @code{enum} without a cast. To solve the problem, insert the required
1327casts (this error occurs once for a @code{CodecID} and once for a
1328@code{CodecType}). The second type of error occurs because C++ requires
1329the return value of @code{malloc} to be cast to the exact type of the
1330pointer it is being assigned to. Visual C++ will complain that, for
1331example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
1332an explicit cast. So insert an explicit cast in these places to silence
1333the compiler. The third type of error occurs because the @code{snprintf}
1334library function is called @code{_snprintf} under Visual C++. So just
1335add an underscore to fix the problem. With these changes,
1336@file{output_example.c} should compile under Visual C++, and the
1337resulting executable should produce valid video files.
1338
1339@end enumerate
1340
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1341@subsection Cross compilation for Windows with Linux
1342
1343You must use the MinGW cross compilation tools available at
1344@url{http://www.mingw.org/}.
1345
4c5f7207 1346Then configure FFmpeg with the following options:
b030b284 1347@example
6b74787b 1348./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
b030b284 1349@end example
019c8838 1350(you can change the cross-prefix according to the prefix chosen for the
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1351MinGW tools).
1352
4c5f7207 1353Then you can easily test FFmpeg with Wine
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1354(@url{http://www.winehq.com/}).
1355
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1356@subsection Compilation under Cygwin
1357
1358Cygwin works very much like Unix.
1359
1360Just install your Cygwin with all the "Base" packages, plus the
1361following "Devel" ones:
1362@example
1363binutils, gcc-core, make, subversion
1364@end example
1365
1366Do not install binutils-20060709-1 (they are buggy on shared builds);
1367use binutils-20050610-1 instead.
1368
1369Then run
1370
1371@example
1372./configure --enable-static --disable-shared
1373@end example
1374
1375to make a static build or
1376
1377@example
1378./configure --enable-shared --disable-static
1379@end example
1380
1381to build shared libraries.
1382
1383If you want to build FFmpeg with additional libraries, download Cygwin
1384"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
1385and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
1386(@url{http://cygwinports.dotsrc.org/}).
1387
1388@subsection Crosscompilation for Windows under Cygwin
1389
ce10ff8e 1390With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
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1391
1392Just install your Cygwin as explained before, plus these additional
1393"Devel" packages:
1394@example
1395gcc-mingw-core, mingw-runtime, mingw-zlib
1396@end example
1397
1398and add some special flags to your configure invocation.
1399
1400For a static build run
1401@example
6b74787b 1402./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
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1403@end example
1404
1405and for a build with shared libraries
1406@example
6b74787b 1407./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
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1408@end example
1409
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1410@section BeOS
1411
1412The configure script should guess the configuration itself.
1413Networking support is currently not finished.
1414errno issues fixed by Andrew Bachmann.
1415
1416Old stuff:
1417
7dd611c9 1418François Revol - revol at free dot fr - April 2002
47d944d2 1419
115329f1 1420The configure script should guess the configuration itself,
ce10ff8e 1421however I still did not test building on the net_server version of BeOS.
47d944d2 1422
4c5f7207 1423FFserver is broken (needs poll() implementation).
47d944d2 1424
4c5f7207 1425There are still issues with errno codes, which are negative in BeOS, and
115329f1 1426that FFmpeg negates when returning. This ends up turning errors into
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1427valid results, then crashes.
1428(To be fixed)
1429
34d7008d 1430@chapter Developers Guide
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1431
1432@section API
a0b72f90 1433@itemize @bullet
9181577c 1434@item libavcodec is the library containing the codecs (both encoding and
4c5f7207 1435decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
9181577c 1436
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1437@item libavformat is the library containing the file format handling (mux and
1438demux code for several formats). Look at @file{ffplay.c} to use it in a
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1439player. See @file{output_example.c} to use it to generate audio or video
1440streams.
1441
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1442@end itemize
1443
1444@section Integrating libavcodec or libavformat in your program
1445
1446You can integrate all the source code of the libraries to link them
1447statically to avoid any version problem. All you need is to provide a
1448'config.mak' and a 'config.h' in the parent directory. See the defines
1449generated by ./configure to understand what is needed.
1450
1451You can use libavcodec or libavformat in your commercial program, but
1452@emph{any patch you make must be published}. The best way to proceed is
4c5f7207 1453to send your patches to the FFmpeg mailing list.
9181577c 1454
80d1c272 1455@node Coding Rules
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1456@section Coding Rules
1457
4c5f7207 1458FFmpeg is programmed in the ISO C90 language with a few additional
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1459features from ISO C99, namely:
1460@itemize @bullet
1461@item
1462the @samp{inline} keyword;
1463@item
1464@samp{//} comments;
1465@item
1466designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
1467@item
114afa9c 1468compound literals (@samp{x = (struct s) @{ 17, 23 @};})
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1469@end itemize
1470
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1471These features are supported by all compilers we care about, so we will not
1472accept patches to remove their use unless they absolutely do not impair
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1473clarity and performance.
1474
4c5f7207 1475All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
cb6e87c1
FH
1476compiles with several other compilers, such as the Compaq ccc compiler
1477or Sun Studio 9, and we would like to keep it that way unless it would
ce10ff8e 1478be exceedingly involved. To ensure compatibility, please do not use any
4c5f7207 1479additional C99 features or GCC extensions. Especially watch out for:
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FH
1480@itemize @bullet
1481@item
1482mixing statements and declarations;
1483@item
1484@samp{long long} (use @samp{int64_t} instead);
1485@item
1486@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
1487@item
019c8838 1488GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
cb6e87c1 1489@end itemize
9181577c 1490
53862e0f 1491Indent size is 4.
b86e38a0 1492The presentation is the one specified by 'indent -i4 -kr -nut'.
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1493The TAB character is forbidden outside of Makefiles as is any
1494form of trailing whitespace. Commits containing either will be
1c1b5a40 1495rejected by the Subversion repository.
9181577c 1496
4c5f7207 1497Main priority in FFmpeg is simplicity and small code size (=less
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1498bugs).
1499
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1500Comments: Use the JavaDoc/Doxygen
1501format (see examples below) so that code documentation
1502can be generated automatically. All nontrivial functions should have a comment
ce10ff8e 1503above them explaining what the function does, even if it is just one sentence.
4c5f7207 1504All structures and their member variables should be documented, too.
f4888b83
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1505@example
1506/**
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1507 * @@file mpeg.c
1508 * MPEG codec.
1509 * @@author ...
1510 */
f4888b83
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1511
1512/**
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1513 * Summary sentence.
1514 * more text ...
1515 * ...
1516 */
114afa9c 1517typedef struct Foobar@{
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1518 int var1; /**< var1 description */
1519 int var2; ///< var2 description
1520 /** var3 description */
1521 int var3;
114afa9c 1522@} Foobar;
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1523
1524/**
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1525 * Summary sentence.
1526 * more text ...
1527 * ...
1528 * @@param my_parameter description of my_parameter
1529 * @@return return value description
1530 */
f4888b83
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1531int myfunc(int my_parameter)
1532...
1533@end example
9181577c 1534
115329f1 1535fprintf and printf are forbidden in libavformat and libavcodec,
36d9b4e8
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1536please use av_log() instead.
1537
1c1b5a40 1538@section Development Policy
7a57b90c
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1539
1540@enumerate
115329f1 1541@item
7a57b90c 1542 You must not commit code which breaks FFmpeg! (Meaning unfinished but
4c5f7207 1543 enabled code which breaks compilation or compiles but does not work or
7a57b90c
MN
1544 breaks the regression tests)
1545 You can commit unfinished stuff (for testing etc), but it must be disabled
1546 (#ifdef etc) by default so it does not interfere with other developers'
1547 work.
115329f1 1548@item
ce10ff8e 1549 You do not have to over-test things. If it works for you, and you think it
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DB
1550 should work for others, then commit. If your code has problems
1551 (portability, triggers compiler bugs, unusual environment etc) they will be
7a57b90c 1552 reported and eventually fixed.
115329f1 1553@item
7a57b90c 1554 Do not commit unrelated changes together, split them into self-contained
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DB
1555 pieces. Also do not forget that if part B depends on part A, but A does not
1556 depend on B, then A can and should be committed first and separate from B.
1557 Keeping changes well split into self-contained parts makes reviewing and
1558 understanding them on the commit log mailing list easier. This also helps
1559 in case of debugging later on.
1560 Also if you have doubts about splitting or not splitting, do not hesitate to
442d1598 1561 ask/discuss it on the developer mailing list.
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1562@item
1563 Do not change behavior of the program (renaming options etc) without
019c8838 1564 first discussing it on the ffmpeg-devel mailing list. Do not remove
7a57b90c 1565 functionality from the code. Just improve!
115329f1 1566
4c5f7207 1567 Note: Redundant code can be removed.
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1568@item
1569 Do not commit changes to the build system (Makefiles, configure script)
019c8838 1570 which change behavior, defaults etc, without asking first. The same
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1571 applies to compiler warning fixes, trivial looking fixes and to code
1572 maintained by other developers. We usually have a reason for doing things
019c8838 1573 the way we do. Send your changes as patches to the ffmpeg-devel mailing
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1574 list, and if the code maintainers say OK, you may commit. This does not
1575 apply to files you wrote and/or maintain.
1576@item
1577 We refuse source indentation and other cosmetic changes if they are mixed
1578 with functional changes, such commits will be rejected and removed. Every
1579 developer has his own indentation style, you should not change it. Of course
1580 if you (re)write something, you can use your own style, even though we would
4c5f7207 1581 prefer if the indentation throughout FFmpeg was consistent (Many projects
ce10ff8e 1582 force a given indentation style - we do not.). If you really need to make
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1583 indentation changes (try to avoid this), separate them strictly from real
1584 changes.
1585
114afa9c 1586 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
ce10ff8e 1587 then either do NOT change the indentation of the inner part within (do not
019c8838 1588 move it to the right)! or do so in a separate commit
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1589@item
1590 Always fill out the commit log message. Describe in a few lines what you
1591 changed and why. You can refer to mailing list postings if you fix a
1592 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1593@item
1594 If you apply a patch by someone else, include the name and email address in
1c1b5a40 1595 the log message. Since the ffmpeg-cvslog mailing list is publicly
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1596 archived you should add some SPAM protection to the email address. Send an
1597 answer to ffmpeg-devel (or wherever you got the patch from) saying that
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1598 you applied the patch.
1599@item
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1600 When applying patches that have been discussed (at length) on the mailing
1601 list, reference the thread in the log message.
1602@item
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1603 Do NOT commit to code actively maintained by others without permission.
1604 Send a patch to ffmpeg-devel instead. If noone answers within a reasonable
1605 timeframe (12h for build failures and security fixes, 3 days small changes,
ce10ff8e 1606 1 week for big patches) then commit your patch if you think it is OK.
5ab0f204 1607 Also note, the maintainer can simply ask for more time to review!
7a57b90c 1608@item
1c1b5a40 1609 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
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1610 are sent there and reviewed by all the other developers. Bugs and possible
1611 improvements or general questions regarding commits are discussed there. We
1612 expect you to react if problems with your code are uncovered.
1613@item
1614 Update the documentation if you change behavior or add features. If you are
019c8838 1615 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
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1616 maintainer(s) will review and commit your stuff.
1617@item
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1618 Try to keep important discussions and requests (also) on the public
1619 developer mailing list, so that all developers can benefit from them.
1620@item
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1621 Never write to unallocated memory, never write over the end of arrays,
1622 always check values read from some untrusted source before using them
1623 as array index or other risky things.
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1624@item
1625 Remember to check if you need to bump versions for the specific libav
f0efbde7 1626 parts (libavutil, libavcodec, libavformat) you are changing. You need
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1627 to change the version integer and the version string.
1628 Incrementing the first component means no backward compatibility to
a940b428 1629 previous versions (e.g. removal of a function from the public API).
76bec1d8 1630 Incrementing the second component means backward compatible change
a940b428 1631 (e.g. addition of a function to the public API).
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1632 Incrementing the third component means a noteworthy binary compatible
1633 change (e.g. encoder bug fix that matters for the decoder).
ebd32fd7 1634@item
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1635 If you add a new codec, remember to update the changelog, add it to
1636 the supported codecs table in the documentation and bump the second
1637 component of the @file{libavcodec} version number appropriately. If
1638 it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
1639 is only a decoder.
65d0bea8 1640@item
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1641 Do not change code to hide warnings without ensuring that the underlying
1642 logic is correct and thus the warning was inappropriate.
114afa9c 1643@end enumerate
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1644
1645We think our rules are not too hard. If you have comments, contact us.
1646
1647Note, these rules are mostly borrowed from the MPlayer project.
1648
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1649@section Submitting patches
1650
ce10ff8e 1651First, (@pxref{Coding Rules}) above if you did not yet.
80d1c272 1652
6a6810b1 1653When you submit your patch, try to send a unified diff (diff '-up'
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1654option). I cannot read other diffs :-)
1655
6e5c1877 1656Also please do not submit patches which contain several unrelated changes.
115329f1 1657Split them into individual self-contained patches; this makes reviewing
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1658them much easier.
1659
9181577c 1660Run the regression tests before submitting a patch so that you can
6bf40f39 1661verify that there are no big problems.
9181577c 1662
9181577c 1663Patches should be posted as base64 encoded attachments (or any other
ce10ff8e 1664encoding which ensures that the patch will not be trashed during
115329f1 1665transmission) to the ffmpeg-devel mailing list, see
2b165e29 1666@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
9181577c 1667
54fcf429 1668It also helps quite a bit if you tell us what the patch does (for example
4c5f7207 1669'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
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1670and has no lrint()')
1671
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1672Also please if you send several patches, send each patch as separate mail,
1673do not attach several unrelated patches to the same mail.
a15bcf70 1674
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1675@section patch submission checklist
1676
1677@enumerate
1678@item
1679 Do the regression tests pass with the patch applied?
1680@item
1681 Is the patch a unified diff?
1682@item
4a7a0908 1683 Is the patch against latest FFmpeg SVN?
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1684@item
1685 Are you subscribed to ffmpeg-dev?
1686 (the list is subscribers only due to spam)
1687@item
1688 Have you checked that the changes are minimal, so that the same cannot be
442d1598 1689 achieved with a smaller patch and/or simpler final code?
dd597cd7 1690@item
4a7a0908 1691 If the change is to speed critical code, did you benchmark it?
dd597cd7 1692@item
442d1598 1693 Have you checked that the patch does not introduce buffer overflows or
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1694 other security issues?
1695@item
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1696 Is the patch created from the root of the source tree, so it can be
1697 applied with @code{patch -p0}?
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1698@item
1699 Does the patch not mix functional and cosmetic changes?
1700@item
1701 Is the patch attached to the email you send?
1702@item
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1703 Is the mime type of the patch correct? It should be text/x-diff or
1704 text/x-patch or at least text/plain and not application/octet-stream.
dd597cd7 1705@item
4a7a0908 1706 If the patch fixes a bug, did you provide a verbose analysis of the bug?
dd597cd7 1707@item
4a7a0908 1708 If the patch fixes a bug, did you provide enough information, including
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1709 a sample, so the bug can be reproduced and the fix can be verified?
1710@item
1711 Did you provide a verbose summary about what the patch does change?
1712@item
1713 Did you provide a verbose explanation why it changes things like it does?
1714@item
442d1598 1715 Did you provide a verbose summary of the user visible advantages and
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1716 disadvantages if the patch is applied?
1717@item
1718 Did you provide an example so we can verify the new feature added by the
1719 patch easily?
1720@item
1721 If you did any benchmarks, did you provide them in the mail?
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1722@item
1723 If you added a new file, did you insert a license header? It should be
6baa2943 1724 taken from FFmpeg, not randomly copied and pasted from somewhere else.
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1725@end enumerate
1726
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1727@section Patch review process
1728
1729All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1730clear note that the patch is not for SVN.
1731Reviews and comments will be posted as replies to the patch on the
ce10ff8e 1732mailing list. The patch submitter then has to take care of every comment,
442d1598 1733that can be by resubmitting a changed patch or by discussion. Resubmitted
ce10ff8e 1734patches will themselves be reviewed like any other patch. If at some point
f5f11d71 1735a patch passes review with no comments then it is approved, that can for
ce10ff8e 1736simple and small patches happen immediately while large patches will generally
f5f11d71 1737have to be changed and reviewed many times before they are approved.
ce10ff8e 1738After a patch is approved it will be committed to the repository.
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1739
1740We will review all submitted patches, but sometimes we are quite busy so
1741especially for large patches this can take several weeks.
1742
1743When resubmitting patches, please do not make any significant changes
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1744not related to the comments received during review. Such patches will
1745be rejected. Instead, submit significant changes or new features as
1746separate patches.
cf7f2b16 1747
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1748@section Regression tests
1749
1c1b5a40 1750Before submitting a patch (or committing to the repository), you should at least
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1751test that you did not break anything.
1752
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1753The regression tests build a synthetic video stream and a synthetic
1754audio stream. These are then encoded and decoded with all codecs or
9181577c 1755formats. The CRC (or MD5) of each generated file is recorded in a
4c5f7207 1756result file. A 'diff' is launched to compare the reference results and
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1757the result file.
1758
4c5f7207 1759The regression tests then go on to test the FFserver code with a
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1760limited set of streams. It is important that this step runs correctly
1761as well.
1762
36d9b4e8 1763Run 'make test' to test all the codecs and formats.
9181577c 1764
4c5f7207 1765Run 'make fulltest' to test all the codecs, formats and FFserver.
9181577c 1766
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1767[Of course, some patches may change the results of the regression tests. In
1768this case, the reference results of the regression tests shall be modified
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1769accordingly].
1770
1771@bye