Add some missing codecs and update names to match the codec long_name
[libav.git] / doc / general.texi
1 \input texinfo @c -*- texinfo -*-
3 @settitle General Documentation
4 @titlepage
5 @sp 7
6 @center @titlefont{General Documentation}
7 @sp 3
8 @end titlepage
11 @chapter external libraries
13 FFmpeg can be hooked up with a number of external libraries to add support
14 for more formats. None of them are used by default, their use has to be
15 explicitly requested by passing the appropriate flags to @file{./configure}.
17 @section AMR
19 AMR comes in two different flavors, wideband and narrowband. FFmpeg can make
20 use of the AMR wideband (floating-point mode) and the AMR narrowband
21 (floating-point mode) reference decoders and encoders.
23 Go to @url{} and follow the instructions for
24 installing the libraries. Then pass @code{--enable-libamr-nb} and/or
25 @code{--enable-libamr-wb} to configure to enable the libraries.
27 Note that libamr is copyrighted without any sort of license grant. This means
28 that you can use it if you legally obtained it but you are not allowed to
29 redistribute it in any way. @strong{Any FFmpeg binaries with libamr support
30 you create are non-free and unredistributable!}
33 @chapter Supported File Formats and Codecs
35 You can use the @code{-formats} option to have an exhaustive list.
37 @section File Formats
39 FFmpeg supports the following file formats through the @code{libavformat}
40 library:
42 @multitable @columnfractions .4 .1 .1 .4
43 @item Name @tab Encoding @tab Decoding @tab Comments
44 @item 4xm @tab @tab X
45 @tab 4X Technologies format, used in some games.
46 @item Audio IFF (AIFF) @tab X @tab X
47 @item American Laser Games MM @tab @tab X
48 @tab Multimedia format used in games like Mad Dog McCree.
49 @item 3GPP AMR @tab X @tab X
50 @item ASF @tab X @tab X
51 @item AVI @tab X @tab X
52 @item AVISynth @tab @tab X
53 @item AVS @tab @tab X
54 @tab Multimedia format used by the Creature Shock game.
55 @item Beam Software SIFF @tab @tab X
56 @tab Audio and video format used in some games by Beam Software.
57 @item Bethesda Softworks VID @tab @tab X
58 @tab Used in some games from Bethesda Softworks.
59 @item Brute Force & Ignorance @tab @tab X
60 @tab Used in the game Flash Traffic: City of Angels.
61 @item Interplay C93 @tab @tab X
62 @tab Used in the game Cyberia from Interplay.
63 @item Delphine Software International CIN @tab @tab X
64 @tab Multimedia format used by Delphine Software games.
65 @item CRC testing format @tab X @tab
66 @item Creative Voice @tab X @tab X
67 @tab Created for the Sound Blaster Pro.
68 @item CRYO APC @tab @tab X
69 @tab Audio format used in some games by CRYO Interactive Entertainment.
70 @item D-Cinema audio @tab X @tab X
71 @item DV video @tab X @tab X
72 @item DXA @tab @tab X
73 @tab This format is used in the non-Windows version of the Feeble Files
74 game and different game cutscenes repacked for use with ScummVM.
75 @item Electronic Arts cdata @tab @tab X
76 @item Electronic Arts Multimedia @tab @tab X
77 @tab Used in various EA games; files have extensions like WVE and UV2.
78 @item FFM (FFserver live feed) @tab X @tab X
79 @item Flash (SWF) @tab X @tab X
80 @item Flash 9 (AVM2) @tab X @tab X
81 @tab Only embedded audio is decoded.
82 @item FLI/FLC/FLX animation @tab @tab X
83 @tab .fli/.flc files
84 @item FLV @tab X @tab X
85 @tab Macromedia Flash video files
86 @item framecrc testing format @tab X @tab
87 @item FunCom ISS @tab @tab X
88 @tab Audio format used in various games from FunCom like The Longest Journey.
89 @item GIF Animation @tab X @tab
90 @item GXF @tab X @tab X
91 @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley
92 playout servers.
93 @item id Cinematic @tab @tab X
94 @tab Used in Quake II.
95 @item id RoQ @tab X @tab X
96 @tab Used in Quake III, Jedi Knight 2, other computer games.
97 @item IFF @tab @tab X
98 @tab Interchange File Format
99 @item Interplay MVE @tab @tab X
100 @tab Format used in various Interplay computer games.
101 @item LMLM4 @tab @tab X
102 @tab Used by Linux Media Labs MPEG-4 PCI boards
103 @item Matroska @tab X @tab X
104 @item Matroska audio @tab X @tab
105 @item MAXIS XA @tab @tab X
106 @tab Used in Sim City 3000; file extension .xa.
107 @item Monkey's Audio @tab @tab X
108 @item Motion Pixels MVI @tab @tab X
109 @item MOV/QuickTime/MP4 @tab X @tab X
110 @tab 3GP, 3GP2, PSP, iPod variants supported
111 @item MP2 @tab X @tab
112 @item MP3 @tab X @tab
113 @item MPEG audio @tab X @tab X
114 @item MPEG-1 System @tab X @tab X
115 @tab muxed audio and video, VCD format supported
116 @item MPEG-PS (program stream) @tab X @tab X
117 @tab also known as @code{VOB} file, SVCD and DVD format supported
118 @item MPEG-TS (transport stream) @tab X @tab X
119 @tab also known as DVB Transport Stream
120 @item MPEG-4 @tab X @tab X
121 @tab MPEG-4 is a variant of QuickTime.
122 @item MIME multipart JPEG @tab X @tab
123 @item MSN TCP webcam @tab @tab X
124 @tab Used by MSN Messenger webcam streams.
125 @item MTV @tab @tab X
126 @item Musepack @tab @tab X
127 @item Musepack SV8 @tab @tab X
128 @item Material eXchange Format (MXF) @tab X @tab X
129 @tab SMPTE 377M, used by D-Cinema, broadcast industry.
130 @item Material eXchange Format (MXF), D-10 Mapping @tab X @tab X
131 @tab SMPTE 386M, D-10/IMX Mapping.
132 @item NC camera feed @tab @tab X
133 @tab NC (AVIP NC4600) camera streams
134 @item Nullsoft Streaming Video @tab @tab X
135 @item NuppelVideo @tab @tab X
136 @item NUT @tab X @tab X
137 @tab NUT Open Container Format
138 @item Ogg @tab X @tab X
139 @item TechnoTrend PVA @tab @tab X
140 @tab Used by TechnoTrend DVB PCI boards.
141 @item raw ADTS (AAC) @tab X @tab X
142 @item raw AC-3 @tab X @tab X
143 @item raw Chinese AVS video @tab @tab X
144 @item raw CRI ADX @tab X @tab X
145 @item raw Dirac @tab X @tab X
146 @item raw DNxHD @tab X @tab X
147 @item raw DTS @tab X @tab X
148 @item raw E-AC-3 @tab X @tab X
149 @item raw FLAC @tab X @tab X
150 @item raw GSM @tab @tab X
151 @item raw H.261 @tab X @tab X
152 @item raw H.263 @tab X @tab X
153 @item raw H.264 @tab X @tab X
154 @item raw Ingenient MJPEG @tab @tab X
155 @item raw MJPEG @tab X @tab X
156 @item raw MLP @tab @tab X
157 @item raw MPEG @tab @tab X
158 @item raw MPEG-1 @tab @tab X
159 @item raw MPEG-2 @tab @tab X
160 @item raw MPEG-4 @tab X @tab X
161 @item raw NULL @tab X @tab
162 @item raw video @tab X @tab X
163 @item raw id RoQ @tab X @tab
164 @item raw Shorten @tab @tab X
165 @item raw VC-1 @tab @tab X
166 @item raw PCM A-law @tab X @tab X
167 @item raw PCM mu-law @tab X @tab X
168 @item raw PCM signed 8 bit @tab X @tab X
169 @item raw PCM signed 16 bit big-endian @tab X @tab X
170 @item raw PCM signed 16 bit little-endian @tab X @tab X
171 @item raw PCM signed 24 bit big-endian @tab X @tab X
172 @item raw PCM signed 24 bit little-endian @tab X @tab X
173 @item raw PCM signed 32 bit big-endian @tab X @tab X
174 @item raw PCM signed 32 bit little-endian @tab X @tab X
175 @item raw PCM unsigned 8 bit @tab X @tab X
176 @item raw PCM unsigned 16 bit big-endian @tab X @tab X
177 @item raw PCM unsigned 16 bit little-endian @tab X @tab X
178 @item raw PCM unsigned 24 bit big-endian @tab X @tab X
179 @item raw PCM unsigned 24 bit little-endian @tab X @tab X
180 @item raw PCM unsigned 32 bit big-endian @tab X @tab X
181 @item raw PCM unsigned 32 bit little-endian @tab X @tab X
182 @item raw PCM floating-point 32 bit big-endian @tab X @tab X
183 @item raw PCM floating-point 32 bit little-endian @tab X @tab X
184 @item raw PCM floating-point 64 bit big-endian @tab X @tab X
185 @item raw PCM floating-point 64 bit little-endian @tab X @tab X
186 @item RDT @tab @tab X
187 @item REDCODE R3D @tab @tab X
188 @tab File format used by RED Digital cameras, contains JPEG 2000 frames and PCM audio.
189 @item RealMedia @tab X @tab X
190 @item Redirector @tab @tab X
191 @item Renderware TeXture Dictionary @tab @tab X
192 @item RL2 @tab @tab X
193 @tab Audio and video format used in some games by Entertainment Software Partners.
194 @item RPL/ARMovie @tab @tab X
195 @item RTP @tab @tab X
196 @item RTSP @tab @tab X
197 @item SDP @tab @tab X
198 @item Sega FILM/CPK @tab @tab X
199 @tab Used in many Sega Saturn console games.
200 @item Sierra SOL @tab @tab X
201 @tab .sol files used in Sierra Online games.
202 @item Sierra VMD @tab @tab X
203 @tab Used in Sierra CD-ROM games.
204 @item Smacker @tab @tab X
205 @tab Multimedia format used by many games.
206 @item Sony OpenMG (OMA) @tab @tab X
207 @tab Audio format used in Sony Sonic Stage and Sony Vegas.
208 @item Sony PlayStation STR @tab @tab X
209 @item SUN AU format @tab X @tab X
210 @item THP @tab @tab X
211 @tab Used on the Nintendo GameCube.
212 @item Tiertex Limited SEQ @tab @tab X
213 @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
214 @item True Audio @tab @tab X
215 @item VC-1 test bitstream @tab X @tab X
216 @item WAV @tab X @tab X
217 @item WavPack @tab @tab X
218 @item Wing Commander III movie @tab @tab X
219 @tab Multimedia format used in Origin's Wing Commander III computer game.
220 @item Westwood Studios audio @tab @tab X
221 @tab Multimedia format used in Westwood Studios games.
222 @item Westwood Studios VQA @tab @tab X
223 @tab Multimedia format used in Westwood Studios games.
224 @item YUV4MPEG pipe @tab X @tab X
225 @end multitable
227 @code{X} means that encoding (resp. decoding) is supported.
229 @section Image Formats
231 FFmpeg can read and write images for each frame of a video sequence. The
232 following image formats are supported:
234 @multitable @columnfractions .4 .1 .1 .4
235 @item Name @tab Encoding @tab Decoding @tab Comments
236 @item .Y.U.V @tab X @tab X
237 @tab one raw file per component
238 @item animated GIF @tab X @tab X
239 @tab Only uncompressed GIFs are generated.
240 @item BMP @tab X @tab X
241 @tab Microsoft BMP image
242 @item JPEG @tab X @tab X
243 @tab Progressive JPEG is not supported.
244 @item JPEG 2000 @tab @tab E
245 @tab decoding supported through external library libopenjpeg
246 @item JPEG-LS @tab X @tab X
247 @item LJPEG @tab X @tab
248 @tab Lossless JPEG
249 @item PAM @tab X @tab X
250 @tab PAM is a PNM extension with alpha support.
251 @item PBM @tab X @tab X
252 @tab Portable BitMap image
253 @item PCX @tab @tab X
254 @tab PC Paintbrush
255 @item PGM @tab X @tab X
256 @tab Portable GrayMap image
257 @item PGMYUV @tab X @tab X
258 @tab PGM with U and V components in YUV 4:2:0
259 @item PNG @tab X @tab X
260 @tab 2/4 bpp not supported yet
261 @item PPM @tab X @tab X
262 @tab Portable PixelMap image
263 @item PTX @tab @tab X
264 @tab V.Flash PTX format
265 @item RAS @tab @tab X
266 @tab Sun Rasterfile
267 @item SGI @tab X @tab X
268 @tab SGI RGB image format
269 @item Targa @tab X @tab X
270 @tab Targa (.TGA) image format
271 @item TIFF @tab X @tab X
272 @tab YUV, JPEG and some extension is not supported yet.
273 @end multitable
275 @code{X} means that encoding (resp. decoding) is supported.
277 @code{E} means that support is provided through an external library.
279 @section Video Codecs
281 @multitable @columnfractions .4 .1 .1 .4
282 @item Name @tab Encoding @tab Decoding @tab Comments
283 @item 4X Movie @tab @tab X
284 @tab Used in certain computer games.
285 @item 8SVX exponential @tab @tab X
286 @item 8SVX fibonacci @tab @tab X
287 @item American Laser Games MM @tab @tab X
288 @tab Used in games like Mad Dog McCree.
289 @item AMV @tab @tab X
290 @tab Used in Chinese MP3 players.
291 @item Apple Animation @tab X @tab X
292 @tab fourcc: 'rle '
293 @item Apple Graphics @tab @tab X
294 @tab fourcc: 'smc '
295 @item Apple MJPEG-B @tab @tab X
296 @item Apple QuickDraw @tab @tab X
297 @tab fourcc: qdrw
298 @item Apple Video @tab @tab X
299 @tab fourcc: rpza
300 @item Asus v1 @tab X @tab X
301 @tab fourcc: ASV1
302 @item Asus v2 @tab X @tab X
303 @tab fourcc: ASV2
304 @item ATI VCR1 @tab @tab X
305 @tab fourcc: VCR1
306 @item ATI VCR2 @tab @tab X
307 @tab fourcc: VCR2
308 @item Autodesk RLE @tab @tab X
309 @tab fourcc: AASC
310 @item AVS (Audio Video Standard) video @tab @tab X
311 @tab Video encoding used by the Creature Shock game.
312 @item Beam Software VB @tab @tab X
313 @item Bethesda VID video @tab @tab X
314 @tab Used in some games from Bethesda Softworks.
315 @item Brute Force & Ignorance @tab @tab X
316 @tab Used in the game Flash Traffic: City of Angels.
317 @item C93 video @tab @tab X
318 @tab Codec used in Cyberia game.
319 @item CamStudio @tab @tab X
320 @tab fourcc: CSCD
321 @item Chinese AVS video @tab @tab X
322 @tab AVS1-P2, JiZhun profile
323 @item Delphine Software International CIN video @tab @tab X
324 @tab Codec used in Delphine Software International games.
325 @item Cinepak @tab @tab X
326 @item Cirrus Logic AccuPak @tab @tab X
327 @tab fourcc: CLJR
328 @item Creative YUV (CYUV) @tab @tab X
329 @item Dirac @tab E @tab E
330 @tab supported through external libdirac/libschroedinger libraries
331 @item DNxHD @tab X @tab X
332 @tab aka SMPTE VC3
333 @item Duck TrueMotion 1.0 @tab @tab X
334 @tab fourcc: DUCK
335 @item Duck TrueMotion 2.0 @tab @tab X
336 @tab fourcc: TM20
337 @item DV (Digital Video) @tab X @tab X
338 @item Feeble Files/ScummVM DXA @tab @tab X
339 @tab Codec originally used in Feeble Files game.
340 @item Electronic Arts CMV video @tab @tab X
341 @tab Used in NHL 95 game.
342 @item Electronic Arts TGV @tab @tab X
343 @item Electronic Arts TGQ @tab @tab X
344 @item Electronic Arts TQI @tab @tab X
345 @item FFmpeg Video 1 @tab X @tab X
346 @tab experimental lossless codec (fourcc: FFV1)
347 @item Flash Screen Video @tab X @tab X
348 @tab fourcc: FSV1
349 @item FLIC video @tab @tab X
350 @item FLV @tab X @tab X
351 @tab Sorenson H.263 used in Flash
352 @item Fraps FPS1 @tab @tab X
353 @item H.261 @tab X @tab X
354 @item H.263(+) @tab X @tab X
355 @tab also known as RealVideo 1.0
356 @item H.264 @tab E @tab X
357 @tab encoding supported through external library libx264
358 @item HuffYUV @tab X @tab X
359 @item IBM Ultimotion @tab @tab X
360 @tab fourcc: ULTI
361 @item id Cinematic video @tab @tab X
362 @tab Used in Quake II.
363 @item id RoQ @tab X @tab X
364 @tab Used in Quake III, Jedi Knight 2, other computer games.
365 @item Intel Indeo 3 @tab @tab X
366 @item Interplay C93 @tab @tab X
367 @tab Used in the game Cyberia from Interplay.
368 @item Interplay Video @tab @tab X
369 @tab Used in Interplay .MVE files.
370 @item JPEG-LS @tab X @tab X
371 @tab fourcc: MJLS, lossless and near-lossless is supported.
372 @item KMVC @tab @tab X
373 @tab Codec used in Worms games.
374 @item LOCO @tab @tab X
375 @item lossless MJPEG @tab X @tab X
376 @item Microsoft RLE @tab @tab X
377 @item Microsoft Video-1 @tab @tab X
378 @item Mimic @tab @tab X
379 @tab Used in MSN Messenger Webcam streams.
380 @item Miro VideoXL @tab @tab X
381 @tab fourcc: VIXL
382 @item MJPEG (Motion JPEG) @tab X @tab X
383 @item Motion Pixels Video @tab @tab X
384 @item MPEG-1 @tab X @tab X
385 @item MPEG-2 @tab X @tab X
386 @item MPEG-4 @tab X @tab X
387 @item MSMPEG4 V1 @tab X @tab X
388 @item MSMPEG4 V2 @tab X @tab X
389 @item MSMPEG4 V3 @tab X @tab X
390 @item MSZH @tab @tab X
391 @tab Part of LCL
392 @item Nintendo Gamecube THP video @tab @tab X
393 @item On2 VP3 @tab @tab X
394 @tab still experimental
395 @item On2 VP5 @tab @tab X
396 @tab fourcc: VP50
397 @item On2 VP6 @tab @tab X
398 @tab fourcc: VP60,VP61,VP62
399 @item planar RGB @tab @tab X
400 @tab fourcc: 8BPS
401 @item QPEG @tab @tab X
402 @tab fourccs: QPEG, Q1.0, Q1.1
403 @item QuickTime 8BPS video @tab @tab X
404 @item RealVideo 1.0 @tab X @tab X
405 @item RealVideo 2.0 @tab X @tab X
406 @item RealVideo 3.0 @tab @tab X
407 @tab still far from ideal
408 @item RealVideo 4.0 @tab @tab X
409 @item Renderware TXD (TeXture Dictionary) @tab @tab X
410 @tab Texture dictionaries used by the Renderware Engine.
411 @item RTjpeg @tab @tab X
412 @tab Video encoding used in NuppelVideo files.
413 @item Sierra VMD video @tab @tab X
414 @tab Used in Sierra VMD files.
415 @item Smacker video @tab @tab X
416 @tab Video encoding used in Smacker.
417 @item SMPTE VC-1 @tab @tab X
418 @item Snow @tab X @tab X
419 @tab experimental wavelet codec (fourcc: SNOW)
420 @item Sony PlayStation MDEC (Motion DECoder) @tab @tab X
421 @item Sorenson Video 1 @tab X @tab X
422 @tab fourcc: SVQ1
423 @item Sorenson Video 3 @tab @tab X
424 @tab fourcc: SVQ3
425 @item Sunplus MJPEG @tab @tab X
426 @tab fourcc: SP5X
427 @item TechSmith Screen Capture Codec @tab @tab X
428 @tab fourcc: TSCC
429 @item Theora @tab E @tab X
430 @tab encoding supported through external library libtheora
431 @item Tiertex Seq video @tab @tab X
432 @tab Codec used in DOS CD-ROM FlashBack game.
433 @item VMware Screen Codec / VMware Video @tab @tab X
434 @tab Codec used in videos captured by VMware.
435 @item Westwood Studios VQA (Vector Quantized Animation) video @tab @tab X
436 @item Windows Media Video 8 @tab X @tab X
437 @item Windows Media Video 9 @tab @tab X
438 @tab not completely working
439 @item Wing Commander III / Xan @tab @tab X
440 @tab Used in Wing Commander III .MVE files.
441 @item Winnov WNV1 @tab @tab X
442 @item WMV7 @tab X @tab X
443 @item YAMAHA SMAF @tab X @tab X
444 @item ZLIB @tab X @tab X
445 @tab part of LCL, encoder experimental
446 @item Zip Motion Blocks Video @tab X @tab X
447 @tab Encoder works only in PAL8.
448 @end multitable
450 @code{X} means that encoding (resp. decoding) is supported.
452 @code{E} means that support is provided through an external library.
454 @section Audio Codecs
456 @multitable @columnfractions .4 .1 .1 .4
457 @item Name @tab Encoding @tab Decoding @tab Comments
458 @item 4X Movie ADPCM @tab @tab X
459 @item 8SVX audio @tab @tab X
460 @item AAC @tab E @tab X
461 @tab encoding supported through external library libfaac
462 @item AC-3 @tab X @tab X
463 @item AMR-NB @tab E @tab E
464 @tab supported through external library libamrnb
465 @item AMR-WB @tab E @tab E
466 @tab supported through external library libamrwb
467 @item Apple lossless audio @tab X @tab X
468 @tab QuickTime fourcc 'alac'
469 @item Apple MACE 3 @tab @tab X
470 @item Apple MACE 6 @tab @tab X
471 @item Atrac 3 @tab @tab X
472 @item CDROM XA ADPCM @tab @tab X
473 @item Delphine Software International CIN audio @tab @tab X
474 @tab Codec used in Delphine Software International games.
475 @item COOK @tab @tab X
476 @tab All versions except 5.1 are supported.
477 @item Creative Technology ADPCM @tab @tab X
478 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
479 @item DCA (DTS Coherent Acoustics) @tab @tab X
480 @item DSP Group TrueSpeech @tab @tab X
481 @item DV audio @tab @tab X
482 @item Electronic Arts ADPCM @tab @tab X
483 @tab Used in various EA titles.
484 @item Electronic Arts Maxis CDROM XS ADPCM @tab @tab X
485 @tab Used in Sim City 3000.
486 @item Electronic Arts R1 ADPCM @tab @tab X
487 @item Electronic Arts R2 ADPCM @tab @tab X
488 @item Electronic Arts R3 ADPCM @tab @tab X
489 @item Electronic Arts XAS ADPCM @tab @tab X
490 @item Enhanced AC-3 @tab @tab X
491 @item FLAC lossless audio @tab IX @tab X
492 @item G.726 ADPCM @tab X @tab X
493 @item GSM @tab E @tab E
494 @tab supported through external library libgsm
495 @item GSM_MS @tab E @tab E
496 @tab supported through external library libgsm
497 @item id RoQ DPCM @tab X @tab X
498 @tab Used in Quake III, Jedi Knight 2, other computer games.
499 @item IMA AMV ADPCM @tab @tab X
500 @tab Used in AMV files
501 @item IMA Electronic Arts EACS ADPCM @tab @tab X
502 @item IMA Electronic Arts SEAD ADPCM @tab @tab X
503 @item IMA Funcom ADPCM @tab @tab X
504 @item IMA QuickTime ADPCM @tab X @tab X
505 @item IMA Loki SDL MJPEG ADPCM @tab @tab X
506 @item IMA WAV ADPCM @tab X @tab X
507 @item IMA Westwood ADPCM @tab @tab X
508 @item Intel Music Coder @tab @tab X
509 @item Interplay DPCM @tab @tab X
510 @tab Used in various Interplay computer games.
511 @item ISS IMA ADPCM @tab @tab X
512 @tab Used in FunCom games.
513 @item IMA Duck DK3 ADPCM @tab @tab X
514 @tab Used in some Sega Saturn console games.
515 @item IMA Duck DK4 ADPCM @tab @tab X
516 @tab Used in some Sega Saturn console games.
517 @item Microsoft ADPCM @tab X @tab X
518 @item MLP/TrueHD @tab @tab X
519 @tab Used in DVD-Audio and Blu-Ray discs.
520 @item Monkey's Audio @tab @tab X
521 @tab Only versions 3.97-3.99 are supported.
522 @item MPEG audio layer 3 @tab E @tab IX
523 @tab encoding supported through external library LAME
524 @item MPEG audio layer 2 @tab IX @tab IX
525 @item MS IMA ADPCM @tab X @tab X
526 @item Musepack @tab @tab X
527 @tab SV7 and SV8 are supported.
528 @item Nellymoser ASAO @tab X @tab X
529 @item Nintendo Gamecube THP ADPCM @tab @tab X
530 @item QCELP / PureVoice @tab @tab X
531 @item Qdesign QDM2 @tab @tab X
532 @tab There are still some distortions.
533 @item QT IMA ADPCM @tab X @tab X
534 @item RA144 @tab @tab X
535 @tab Real 14400 bit/s codec
536 @item RA288 @tab @tab X
537 @tab Real 28800 bit/s codec
538 @item RADnet @tab IX @tab IX
539 @tab Real low bitrate AC-3 codec
540 @item SEGA CRI ADX ADPCM @tab X @tab X
541 @tab Used in Sega Dreamcast games.
542 @item Shockwave Flash ADPCM @tab X @tab X
543 @item Shorten @tab @tab X
544 @item Sierra Online DPCM @tab @tab X
545 @tab Used in Sierra Online game audio files.
546 @item Sierra VMD audio @tab @tab X
547 @tab Used in Sierra VMD files.
548 @item Smacker audio @tab @tab X
549 @item SMJPEG IMA ADPCM @tab @tab X
550 @tab Used in certain Loki game ports.
551 @item Sol DPCM @tab @tab X
552 @item Sonic @tab X @tab X
553 @tab experimental codec
554 @item Sonic lossless @tab X @tab X
555 @tab experimental codec
556 @item Sound Blaster Pro 2-bit ADPCM @tab @tab X
557 @item Sound Blaster Pro 2.6-bit ADPCM @tab @tab X
558 @item Sound Blaster Pro 4-bit ADPCM @tab @tab X
559 @item Speex @tab @tab E
560 @tab supported through external library libspeex
561 @item True Audio (TTA) @tab @tab X
562 @item Vorbis @tab X @tab X
563 @item WavPack @tab @tab X
564 @item Westwood Studios IMA ADPCM @tab @tab X
565 @tab Used in Westwood Studios games like Command and Conquer.
566 @item Westwood Audio (SND1) @tab @tab X
567 @item Windows Media Audio 1 @tab X @tab X
568 @item Windows Media Audio 2 @tab X @tab X
569 @item Xan DPCM @tab @tab X
570 @tab Used in Origin's Wing Commander IV AVI files.
571 @item Yamaha ADPCM @tab X @tab X
572 @end multitable
574 @code{X} means that encoding (resp. decoding) is supported.
576 @code{E} means that support is provided through an external library.
578 @code{I} means that an integer-only version is available, too (ensures high
579 performance on systems without hardware floating point support).
581 @section Subtitle Formats
583 @multitable @columnfractions .4 .1 .1 .1 .1 .1
584 @item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding
585 @item SSA/ASS @tab X @tab X
586 @item DVB @tab X @tab X @tab X @tab X
587 @item DVD @tab X @tab X @tab X @tab X
588 @item XSUB @tab @tab @tab @tab X
589 @end multitable
591 @code{X} means that the feature is supported.
593 @section Network Protocols
595 @multitable @columnfractions .4 .1 .1 .1 .1 .1
596 @item Name @tab Support
597 @item file @tab X
598 @item Gopher @tab X
599 @item HTTP @tab X
600 @item pipe @tab X
601 @item RTP @tab X
602 @item TCP @tab X
603 @item UDP @tab X
604 @end multitable
606 @code{X} means that the protocol is supported.
609 @chapter Platform Specific information
611 @section BSD
613 BSD make will not build FFmpeg, you need to install and use GNU Make
614 (@file{gmake}).
616 @section Windows
618 To get help and instructions for building FFmpeg under Windows, check out
619 the FFmpeg Windows Help Forum at
620 @url{}.
622 @subsection Native Windows compilation
624 FFmpeg can be built to run natively on Windows using the MinGW tools. Install
625 the latest versions of MSYS and MinGW from @url{}.
626 You can find detailed installation
627 instructions in the download section and the FAQ.
629 FFmpeg does not build out-of-the-box with the packages the automated MinGW
630 installer provides. It also requires coreutils to be installed and many other
631 packages updated to the latest version. The minimum version for some packages
632 are listed below:
634 @itemize
635 @item bash 3.1
636 @item msys-make 3.81-2 (note: not mingw32-make)
637 @item w32api 3.13
638 @item mingw-runtime 3.15
639 @end itemize
641 You will also need to pass @code{-fno-common} to the compiler to work around
642 a GCC bug (see @url{}).
644 Within the MSYS shell, configure and make with:
646 @example
647 ./configure --enable-memalign-hack --extra-cflags=-fno-common
648 make
649 make install
650 @end example
652 This will install @file{ffmpeg.exe} along with many other development files
653 to @file{/usr/local}. You may specify another install path using the
654 @code{--prefix} option in @file{configure}.
656 Notes:
658 @itemize
660 @item In order to compile vhooks, you must have a POSIX-compliant libdl in
661 your MinGW system. Get dlfcn-win32 from
662 @url{}.
664 @item In order to compile FFplay, you must have the MinGW development library
665 of SDL. Get it from @url{}.
666 Edit the @file{bin/sdl-config} script so that it points to the correct prefix
667 where SDL was installed. Verify that @file{sdl-config} can be launched from
668 the MSYS command line.
670 @item By using @code{./configure --enable-shared} when configuring FFmpeg,
671 you can build libavutil, libavcodec and libavformat as DLLs.
673 @end itemize
675 @subsection Microsoft Visual C++ compatibility
677 As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
678 want to use the libav* libraries in your own applications, you can still
679 compile those applications using MSVC++. But the libav* libraries you link
680 to @emph{must} be built with MinGW. However, you will not be able to debug
681 inside the libav* libraries, since MSVC++ does not recognize the debug
682 symbols generated by GCC.
683 We strongly recommend you to move over from MSVC++ to MinGW tools.
685 This description of how to use the FFmpeg libraries with MSVC++ is based on
686 Microsoft Visual C++ 2005 Express Edition. If you have a different version,
687 you might have to modify the procedures slightly.
689 @subsubsection Using static libraries
691 Assuming you have just built and installed FFmpeg in @file{/usr/local}.
693 @enumerate
695 @item Create a new console application ("File / New / Project") and then
696 select "Win32 Console Application". On the appropriate page of the
697 Application Wizard, uncheck the "Precompiled headers" option.
699 @item Write the source code for your application, or, for testing, just
700 copy the code from an existing sample application into the source file
701 that MSVC++ has already created for you. For example, you can copy
702 @file{output_example.c} from the FFmpeg distribution.
704 @item Open the "Project / Properties" dialog box. In the "Configuration"
705 combo box, select "All Configurations" so that the changes you make will
706 affect both debug and release builds. In the tree view on the left hand
707 side, select "C/C++ / General", then edit the "Additional Include
708 Directories" setting to contain the path where the FFmpeg includes were
709 installed (i.e. @file{c:\msys\1.0\local\include}).
710 Do not add MinGW's include directory here, or the include files will
711 conflict with MSVC's.
713 @item Still in the "Project / Properties" dialog box, select
714 "Linker / General" from the tree view and edit the
715 "Additional Library Directories" setting to contain the @file{lib}
716 directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
717 the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
718 and the directory where MinGW's GCC libs are installed
719 (i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
720 "Linker / Input" from the tree view, and add the files @file{libavformat.a},
721 @file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
722 @file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
723 to the end of "Additional Dependencies".
725 @item Now, select "C/C++ / Code Generation" from the tree view. Select
726 "Debug" in the "Configuration" combo box. Make sure that "Runtime
727 Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
728 the "Configuration" combo box and make sure that "Runtime Library" is
729 set to "Multi-threaded DLL".
731 @item Click "OK" to close the "Project / Properties" dialog box.
733 @item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
734 Get msinttypes from @url{}
735 and install it in MSVC++'s include directory
736 (i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
738 @item MSVC++ also does not understand the @code{inline} keyword used by
739 FFmpeg, so you must add this line before @code{#include}ing libav*:
740 @example
741 #define inline _inline
742 @end example
744 @item Build your application, everything should work.
746 @end enumerate
748 @subsubsection Using shared libraries
750 This is how to create DLL and LIB files that are compatible with MSVC++:
752 @enumerate
754 @item Add a call to @file{vcvars32.bat} (which sets up the environment
755 variables for the Visual C++ tools) as the first line of @file{msys.bat}.
756 The standard location for @file{vcvars32.bat} is
757 @file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
758 and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
759 If this corresponds to your setup, add the following line as the first line
760 of @file{msys.bat}:
762 @example
763 call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
764 @end example
766 Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
767 and run @file{c:\msys\1.0\msys.bat} from there.
769 @item Within the MSYS shell, run @code{lib.exe}. If you get a help message
770 from @file{Microsoft (R) Library Manager}, this means your environment
771 variables are set up correctly, the @file{Microsoft (R) Library Manager}
772 is on the path and will be used by FFmpeg to create
773 MSVC++-compatible import libraries.
775 @item Build FFmpeg with
777 @example
778 ./configure --enable-shared --enable-memalign-hack
779 make
780 make install
781 @end example
783 Your install path (@file{/usr/local/} by default) should now have the
784 necessary DLL and LIB files under the @file{bin} directory.
786 @end enumerate
788 To use those files with MSVC++, do the same as you would do with
789 the static libraries, as described above. But in Step 4,
790 you should only need to add the directory where the LIB files are installed
791 (i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
792 installed in the @file{bin} directory. And instead of adding @file{libxx.a}
793 files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
794 @file{avutil.lib}. There should be no need for @file{libmingwex.a},
795 @file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
796 statically linked into the DLLs. The @file{bin} directory contains a bunch
797 of DLL files, but the ones that are actually used to run your application
798 are the ones with a major version number in their filenames
799 (i.e. @file{avcodec-51.dll}).
801 @subsection Cross compilation for Windows with Linux
803 You must use the MinGW cross compilation tools available at
804 @url{}.
806 Then configure FFmpeg with the following options:
807 @example
808 ./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
809 @end example
810 (you can change the cross-prefix according to the prefix chosen for the
811 MinGW tools).
813 Then you can easily test FFmpeg with Wine
814 (@url{}).
816 @subsection Compilation under Cygwin
818 The main issue with the 1.5.x Cygwin versions is that newlib, its C library,
819 does not contain llrint(). You need to upgrade to the unstable 1.7.x versions,
820 or leverage the implementation in MinGW (as explained below).
822 Just install your Cygwin with all the "Base" packages, plus the
823 following "Devel" ones:
824 @example
825 binutils, gcc-core, make, subversion, mingw-runtime, diffutils
826 @end example
828 The experimental gcc4 package is still buggy, hence please
829 use the official gcc 3.4.4 or a 4.2.x compiled from source by yourself.
831 Install the current binutils-20080624-2 as they work fine (the old
832 binutils-20060709-1 proved buggy on shared builds).
834 Then create a small library that just contains llrint():
836 @example
837 ar x /usr/lib/mingw/libmingwex.a llrint.o
838 ar cq /usr/local/lib/libllrint.a llrint.o
839 @end example
841 Then run
843 @example
844 ./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
845 @end example
847 to make a static build or
849 @example
850 ./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
851 @end example
853 to build shared libraries.
855 If you want to build FFmpeg with additional libraries, download Cygwin
856 "Devel" packages for Ogg and Vorbis from any Cygwin packages repository:
857 @example
858 libogg-devel, libvorbis-devel
859 @end example
861 These library packages are only available from Cygwin Ports
862 (@url{}) :
864 @example
865 yasm, libSDL-devel, libdirac-devel, libfaac-devel, libfaad-devel, libgsm-devel,
866 libmp3lame-devel, libschroedinger1.0-devel, speex-devel, libtheora-devel,
867 libxvidcore-devel
868 @end example
870 The recommendation for libnut and x264 is to build them from source by
871 yourself, as they evolve too quickly for Cygwin Ports to be up to date.
873 Cygwin 1.7.x has IPv6 support. You can add IPv6 to Cygwin 1.5.x by means
874 of the @code{libgetaddrinfo-devel} package, available at Cygwin Ports.
876 @subsection Crosscompilation for Windows under Cygwin
878 With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
880 Just install your Cygwin as explained before, plus these additional
881 "Devel" packages:
882 @example
883 gcc-mingw-core, mingw-runtime, mingw-zlib
884 @end example
886 and add some special flags to your configure invocation.
888 For a static build run
889 @example
890 ./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
891 @end example
893 and for a build with shared libraries
894 @example
895 ./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
896 @end example
898 @section BeOS
900 BeOS support is broken in mysterious ways.
902 @section OS/2
904 For information about compiling FFmpeg on OS/2 see
905 @url{}.
907 @chapter Developers Guide
909 @section API
910 @itemize @bullet
911 @item libavcodec is the library containing the codecs (both encoding and
912 decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
914 @item libavformat is the library containing the file format handling (mux and
915 demux code for several formats). Look at @file{ffplay.c} to use it in a
916 player. See @file{output_example.c} to use it to generate audio or video
917 streams.
919 @end itemize
921 @section Integrating libavcodec or libavformat in your program
923 You can integrate all the source code of the libraries to link them
924 statically to avoid any version problem. All you need is to provide a
925 'config.mak' and a 'config.h' in the parent directory. See the defines
926 generated by ./configure to understand what is needed.
928 You can use libavcodec or libavformat in your commercial program, but
929 @emph{any patch you make must be published}. The best way to proceed is
930 to send your patches to the FFmpeg mailing list.
932 @node Coding Rules
933 @section Coding Rules
935 FFmpeg is programmed in the ISO C90 language with a few additional
936 features from ISO C99, namely:
937 @itemize @bullet
938 @item
939 the @samp{inline} keyword;
940 @item
941 @samp{//} comments;
942 @item
943 designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
944 @item
945 compound literals (@samp{x = (struct s) @{ 17, 23 @};})
946 @end itemize
948 These features are supported by all compilers we care about, so we will not
949 accept patches to remove their use unless they absolutely do not impair
950 clarity and performance.
952 All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
953 compiles with several other compilers, such as the Compaq ccc compiler
954 or Sun Studio 9, and we would like to keep it that way unless it would
955 be exceedingly involved. To ensure compatibility, please do not use any
956 additional C99 features or GCC extensions. Especially watch out for:
957 @itemize @bullet
958 @item
959 mixing statements and declarations;
960 @item
961 @samp{long long} (use @samp{int64_t} instead);
962 @item
963 @samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
964 @item
965 GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
966 @end itemize
968 Indent size is 4.
969 The presentation is the one specified by 'indent -i4 -kr -nut'.
970 The TAB character is forbidden outside of Makefiles as is any
971 form of trailing whitespace. Commits containing either will be
972 rejected by the Subversion repository.
974 The main priority in FFmpeg is simplicity and small code size in order to
975 minimize the bug count.
977 Comments: Use the JavaDoc/Doxygen
978 format (see examples below) so that code documentation
979 can be generated automatically. All nontrivial functions should have a comment
980 above them explaining what the function does, even if it is just one sentence.
981 All structures and their member variables should be documented, too.
982 @example
983 /**
984 * @@file mpeg.c
985 * MPEG codec.
986 * @@author ...
987 */
989 /**
990 * Summary sentence.
991 * more text ...
992 * ...
993 */
994 typedef struct Foobar@{
995 int var1; /**< var1 description */
996 int var2; ///< var2 description
997 /** var3 description */
998 int var3;
999 @} Foobar;
1001 /**
1002 * Summary sentence.
1003 * more text ...
1004 * ...
1005 * @@param my_parameter description of my_parameter
1006 * @@return return value description
1007 */
1008 int myfunc(int my_parameter)
1009 ...
1010 @end example
1012 fprintf and printf are forbidden in libavformat and libavcodec,
1013 please use av_log() instead.
1015 Casts should be used only when necessary. Unneeded parentheses
1016 should also be avoided if they don't make the code easier to understand.
1018 @section Development Policy
1020 @enumerate
1021 @item
1022 Contributions should be licensed under the LGPL 2.1, including an
1023 "or any later version" clause, or the MIT license. GPL 2 including
1024 an "or any later version" clause is also acceptable, but LGPL is
1025 preferred.
1026 @item
1027 You must not commit code which breaks FFmpeg! (Meaning unfinished but
1028 enabled code which breaks compilation or compiles but does not work or
1029 breaks the regression tests)
1030 You can commit unfinished stuff (for testing etc), but it must be disabled
1031 (#ifdef etc) by default so it does not interfere with other developers'
1032 work.
1033 @item
1034 You do not have to over-test things. If it works for you, and you think it
1035 should work for others, then commit. If your code has problems
1036 (portability, triggers compiler bugs, unusual environment etc) they will be
1037 reported and eventually fixed.
1038 @item
1039 Do not commit unrelated changes together, split them into self-contained
1040 pieces. Also do not forget that if part B depends on part A, but A does not
1041 depend on B, then A can and should be committed first and separate from B.
1042 Keeping changes well split into self-contained parts makes reviewing and
1043 understanding them on the commit log mailing list easier. This also helps
1044 in case of debugging later on.
1045 Also if you have doubts about splitting or not splitting, do not hesitate to
1046 ask/discuss it on the developer mailing list.
1047 @item
1048 Do not change behavior of the program (renaming options etc) without
1049 first discussing it on the ffmpeg-devel mailing list. Do not remove
1050 functionality from the code. Just improve!
1052 Note: Redundant code can be removed.
1053 @item
1054 Do not commit changes to the build system (Makefiles, configure script)
1055 which change behavior, defaults etc, without asking first. The same
1056 applies to compiler warning fixes, trivial looking fixes and to code
1057 maintained by other developers. We usually have a reason for doing things
1058 the way we do. Send your changes as patches to the ffmpeg-devel mailing
1059 list, and if the code maintainers say OK, you may commit. This does not
1060 apply to files you wrote and/or maintain.
1061 @item
1062 We refuse source indentation and other cosmetic changes if they are mixed
1063 with functional changes, such commits will be rejected and removed. Every
1064 developer has his own indentation style, you should not change it. Of course
1065 if you (re)write something, you can use your own style, even though we would
1066 prefer if the indentation throughout FFmpeg was consistent (Many projects
1067 force a given indentation style - we do not.). If you really need to make
1068 indentation changes (try to avoid this), separate them strictly from real
1069 changes.
1071 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1072 then either do NOT change the indentation of the inner part within (do not
1073 move it to the right)! or do so in a separate commit
1074 @item
1075 Always fill out the commit log message. Describe in a few lines what you
1076 changed and why. You can refer to mailing list postings if you fix a
1077 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1078 @item
1079 If you apply a patch by someone else, include the name and email address in
1080 the log message. Since the ffmpeg-cvslog mailing list is publicly
1081 archived you should add some SPAM protection to the email address. Send an
1082 answer to ffmpeg-devel (or wherever you got the patch from) saying that
1083 you applied the patch.
1084 @item
1085 When applying patches that have been discussed (at length) on the mailing
1086 list, reference the thread in the log message.
1087 @item
1088 Do NOT commit to code actively maintained by others without permission.
1089 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
1090 timeframe (12h for build failures and security fixes, 3 days small changes,
1091 1 week for big patches) then commit your patch if you think it is OK.
1092 Also note, the maintainer can simply ask for more time to review!
1093 @item
1094 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1095 are sent there and reviewed by all the other developers. Bugs and possible
1096 improvements or general questions regarding commits are discussed there. We
1097 expect you to react if problems with your code are uncovered.
1098 @item
1099 Update the documentation if you change behavior or add features. If you are
1100 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1101 maintainer(s) will review and commit your stuff.
1102 @item
1103 Try to keep important discussions and requests (also) on the public
1104 developer mailing list, so that all developers can benefit from them.
1105 @item
1106 Never write to unallocated memory, never write over the end of arrays,
1107 always check values read from some untrusted source before using them
1108 as array index or other risky things.
1109 @item
1110 Remember to check if you need to bump versions for the specific libav
1111 parts (libavutil, libavcodec, libavformat) you are changing. You need
1112 to change the version integer.
1113 Incrementing the first component means no backward compatibility to
1114 previous versions (e.g. removal of a function from the public API).
1115 Incrementing the second component means backward compatible change
1116 (e.g. addition of a function to the public API or extension of an
1117 existing data structure).
1118 Incrementing the third component means a noteworthy binary compatible
1119 change (e.g. encoder bug fix that matters for the decoder).
1120 @item
1121 Compiler warnings indicate potential bugs or code with bad style. If a type of
1122 warning always points to correct and clean code, that warning should
1123 be disabled, not the code changed.
1124 Thus the remaining warnings can either be bugs or correct code.
1125 If it is a bug, the bug has to be fixed. If it is not, the code should
1126 be changed to not generate a warning unless that causes a slowdown
1127 or obfuscates the code.
1128 @item
1129 If you add a new file, give it a proper license header. Do not copy and
1130 paste it from a random place, use an existing file as template.
1131 @end enumerate
1133 We think our rules are not too hard. If you have comments, contact us.
1135 Note, these rules are mostly borrowed from the MPlayer project.
1137 @section Submitting patches
1139 First, (@pxref{Coding Rules}) above if you did not yet.
1141 When you submit your patch, try to send a unified diff (diff '-up'
1142 option). We cannot read other diffs :-)
1144 Also please do not submit a patch which contains several unrelated changes.
1145 Split it into separate, self-contained pieces. This does not mean splitting
1146 file by file. Instead, make the patch as small as possible while still
1147 keeping it as a logical unit that contains an individual change, even
1148 if it spans multiple files. This makes reviewing your patches much easier
1149 for us and greatly increases your chances of getting your patch applied.
1151 Run the regression tests before submitting a patch so that you can
1152 verify that there are no big problems.
1154 Patches should be posted as base64 encoded attachments (or any other
1155 encoding which ensures that the patch will not be trashed during
1156 transmission) to the ffmpeg-devel mailing list, see
1157 @url{}
1159 It also helps quite a bit if you tell us what the patch does (for example
1160 'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1161 and has no lrint()')
1163 Also please if you send several patches, send each patch as a separate mail,
1164 do not attach several unrelated patches to the same mail.
1166 @section New codecs or formats checklist
1168 @enumerate
1169 @item
1170 Did you use av_cold for codec initialization and close functions?
1171 @item
1172 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
1173 AVInputFormat/AVOutputFormat struct?
1174 @item
1175 Did you bump the minor version number in @file{avcodec.h} or
1176 @file{avformat.h}?
1177 @item
1178 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
1179 @item
1180 Did you add the CodecID to @file{avcodec.h}?
1181 @item
1182 If it has a fourcc, did you add it to @file{libavformat/riff.c},
1183 even if it is only a decoder?
1184 @item
1185 Did you add a rule to compile the appropriate files in the Makefile?
1186 Remember to do this even if you're just adding a format to a file that is
1187 already being compiled by some other rule, like a raw demuxer.
1188 @item
1189 Did you add an entry to the table of supported formats or codecs in the
1190 documentation?
1191 @item
1192 Did you add an entry in the Changelog?
1193 @item
1194 If it depends on a parser or a library, did you add that dependency in
1195 configure?
1196 @item
1197 Did you "svn add" the appropriate files before commiting?
1198 @end enumerate
1200 @section patch submission checklist
1202 @enumerate
1203 @item
1204 Do the regression tests pass with the patch applied?
1205 @item
1206 Does @code{make checkheaders} pass with the patch applied?
1207 @item
1208 Is the patch a unified diff?
1209 @item
1210 Is the patch against latest FFmpeg SVN?
1211 @item
1212 Are you subscribed to ffmpeg-dev?
1213 (the list is subscribers only due to spam)
1214 @item
1215 Have you checked that the changes are minimal, so that the same cannot be
1216 achieved with a smaller patch and/or simpler final code?
1217 @item
1218 If the change is to speed critical code, did you benchmark it?
1219 @item
1220 If you did any benchmarks, did you provide them in the mail?
1221 @item
1222 Have you checked that the patch does not introduce buffer overflows or
1223 other security issues?
1224 @item
1225 Did you test your decoder or demuxer against damaged data? If no, see
1226 tools/trasher and the noise bitstream filter. Your decoder or demuxer
1227 should not crash or end in a (near) infinite loop when fed damaged data.
1228 @item
1229 Is the patch created from the root of the source tree, so it can be
1230 applied with @code{patch -p0}?
1231 @item
1232 Does the patch not mix functional and cosmetic changes?
1233 @item
1234 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1235 @item
1236 Is the patch attached to the email you send?
1237 @item
1238 Is the mime type of the patch correct? It should be text/x-diff or
1239 text/x-patch or at least text/plain and not application/octet-stream.
1240 @item
1241 If the patch fixes a bug, did you provide a verbose analysis of the bug?
1242 @item
1243 If the patch fixes a bug, did you provide enough information, including
1244 a sample, so the bug can be reproduced and the fix can be verified?
1245 Note please do not attach samples >100k to mails but rather provide a
1246 URL, you can upload to
1247 @item
1248 Did you provide a verbose summary about what the patch does change?
1249 @item
1250 Did you provide a verbose explanation why it changes things like it does?
1251 @item
1252 Did you provide a verbose summary of the user visible advantages and
1253 disadvantages if the patch is applied?
1254 @item
1255 Did you provide an example so we can verify the new feature added by the
1256 patch easily?
1257 @item
1258 If you added a new file, did you insert a license header? It should be
1259 taken from FFmpeg, not randomly copied and pasted from somewhere else.
1260 @item
1261 You should maintain alphabetical order in alphabetically ordered lists as
1262 long as doing so does not break API/ABI compatibility.
1263 @item
1264 Lines with similar content should be aligned vertically when doing so
1265 improves readability.
1266 @item
1267 Did you provide a suggestion for a clear commit log message?
1268 @end enumerate
1270 @section Patch review process
1272 All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1273 clear note that the patch is not for SVN.
1274 Reviews and comments will be posted as replies to the patch on the
1275 mailing list. The patch submitter then has to take care of every comment,
1276 that can be by resubmitting a changed patch or by discussion. Resubmitted
1277 patches will themselves be reviewed like any other patch. If at some point
1278 a patch passes review with no comments then it is approved, that can for
1279 simple and small patches happen immediately while large patches will generally
1280 have to be changed and reviewed many times before they are approved.
1281 After a patch is approved it will be committed to the repository.
1283 We will review all submitted patches, but sometimes we are quite busy so
1284 especially for large patches this can take several weeks.
1286 When resubmitting patches, please do not make any significant changes
1287 not related to the comments received during review. Such patches will
1288 be rejected. Instead, submit significant changes or new features as
1289 separate patches.
1291 @section Regression tests
1293 Before submitting a patch (or committing to the repository), you should at least
1294 test that you did not break anything.
1296 The regression tests build a synthetic video stream and a synthetic
1297 audio stream. These are then encoded and decoded with all codecs or
1298 formats. The CRC (or MD5) of each generated file is recorded in a
1299 result file. A 'diff' is launched to compare the reference results and
1300 the result file.
1302 The regression tests then go on to test the FFserver code with a
1303 limited set of streams. It is important that this step runs correctly
1304 as well.
1306 Run 'make test' to test all the codecs and formats.
1308 Run 'make fulltest' to test all the codecs, formats and FFserver.
1310 [Of course, some patches may change the results of the regression tests. In
1311 this case, the reference results of the regression tests shall be modified
1312 accordingly].
1314 @bye