1 \input texinfo @c -*- texinfo -*-
3 @settitle General Documentation
6 @center @titlefont{General Documentation}
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}.
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{http://www.penguin.cz/~utx/amr} 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.
39 FFmpeg supports the following file formats through the @code{libavformat}
42 @multitable @columnfractions .4 .1 .1 .4
43 @item Name @tab Encoding @tab Decoding @tab Comments
45 @tab 4X Technologies format, used in some games.
46 @item 8088flex TMV @tab @tab X
47 @item Audio IFF (AIFF) @tab X @tab X
48 @item American Laser Games MM @tab @tab X
49 @tab Multimedia format used in games like Mad Dog McCree.
50 @item 3GPP AMR @tab X @tab X
51 @item ASF @tab X @tab X
52 @item AVI @tab X @tab X
53 @item AVISynth @tab @tab X
55 @tab Multimedia format used by the Creature Shock game.
56 @item Beam Software SIFF @tab @tab X
57 @tab Audio and video format used in some games by Beam Software.
58 @item Bethesda Softworks VID @tab @tab X
59 @tab Used in some games from Bethesda Softworks.
60 @item Brute Force & Ignorance @tab @tab X
61 @tab Used in the game Flash Traffic: City of Angels.
62 @item Interplay C93 @tab @tab X
63 @tab Used in the game Cyberia from Interplay.
64 @item Delphine Software International CIN @tab @tab X
65 @tab Multimedia format used by Delphine Software games.
66 @item CRC testing format @tab X @tab
67 @item Creative Voice @tab X @tab X
68 @tab Created for the Sound Blaster Pro.
69 @item CRYO APC @tab @tab X
70 @tab Audio format used in some games by CRYO Interactive Entertainment.
71 @item D-Cinema audio @tab X @tab X
72 @item DV video @tab X @tab X
74 @tab This format is used in the non-Windows version of the Feeble Files
75 game and different game cutscenes repacked for use with ScummVM.
76 @item Electronic Arts cdata @tab @tab X
77 @item Electronic Arts Multimedia @tab @tab X
78 @tab Used in various EA games; files have extensions like WVE and UV2.
79 @item FFM (FFserver live feed) @tab X @tab X
80 @item Flash (SWF) @tab X @tab X
81 @item Flash 9 (AVM2) @tab X @tab X
82 @tab Only embedded audio is decoded.
83 @item FLI/FLC/FLX animation @tab @tab X
85 @item Flash Video (FLV) @tab @tab X
86 @tab Macromedia Flash video files
87 @item framecrc testing format @tab X @tab
88 @item FunCom ISS @tab @tab X
89 @tab Audio format used in various games from FunCom like The Longest Journey.
90 @item GIF Animation @tab X @tab
91 @item GXF @tab X @tab X
92 @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley
94 @item id Quake II CIN video @tab @tab X
95 @item id RoQ @tab X @tab X
96 @tab Used in Quake III, Jedi Knight 2, other computer games.
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 X
112 @item MP3 @tab X @tab X
113 @item MPEG-1 System @tab X @tab X
114 @tab muxed audio and video, VCD format supported
115 @item MPEG-PS (program stream) @tab X @tab X
116 @tab also known as @code{VOB} file, SVCD and DVD format supported
117 @item MPEG-TS (transport stream) @tab X @tab X
118 @tab also known as DVB Transport Stream
119 @item MPEG-4 @tab X @tab X
120 @tab MPEG-4 is a variant of QuickTime.
121 @item MIME multipart JPEG @tab X @tab
122 @item MSN TCP webcam @tab @tab X
123 @tab Used by MSN Messenger webcam streams.
124 @item MTV @tab @tab X
125 @item Musepack @tab @tab X
126 @item Musepack SV8 @tab @tab X
127 @item Material eXchange Format (MXF) @tab X @tab X
128 @tab SMPTE 377M, used by D-Cinema, broadcast industry.
129 @item Material eXchange Format (MXF), D-10 Mapping @tab X @tab X
130 @tab SMPTE 386M, D-10/IMX Mapping.
131 @item NC camera feed @tab @tab X
132 @tab NC (AVIP NC4600) camera streams
133 @item NTT TwinVQ (VQF) @tab @tab X
134 @tab Nippon Telegraph and Telephone Corporation TwinVQ.
135 @item Nullsoft Streaming Video @tab @tab X
136 @item NuppelVideo @tab @tab X
137 @item NUT @tab X @tab X
138 @tab NUT Open Container Format
139 @item Ogg @tab X @tab X
140 @item TechnoTrend PVA @tab @tab X
141 @tab Used by TechnoTrend DVB PCI boards.
142 @item raw ADTS (AAC) @tab X @tab X
143 @item raw AC-3 @tab X @tab X
144 @item raw Chinese AVS video @tab @tab X
145 @item raw CRI ADX @tab X @tab X
146 @item raw Dirac @tab X @tab X
147 @item raw DNxHD @tab X @tab X
148 @item raw DTS @tab X @tab X
149 @item raw E-AC-3 @tab X @tab X
150 @item raw FLAC @tab X @tab X
151 @item raw GSM @tab @tab X
152 @item raw H.261 @tab X @tab X
153 @item raw H.263 @tab X @tab X
154 @item raw H.264 @tab X @tab X
155 @item raw Ingenient MJPEG @tab @tab X
156 @item raw MJPEG @tab X @tab X
157 @item raw MLP @tab @tab X
158 @item raw MPEG @tab @tab X
159 @item raw MPEG-1 @tab @tab X
160 @item raw MPEG-2 @tab @tab X
161 @item raw MPEG-4 @tab X @tab X
162 @item raw NULL @tab X @tab
163 @item raw video @tab X @tab X
164 @item raw id RoQ @tab X @tab
165 @item raw Shorten @tab @tab X
166 @item raw TrueHD @tab X @tab X
167 @item raw VC-1 @tab @tab X
168 @item raw PCM A-law @tab X @tab X
169 @item raw PCM mu-law @tab X @tab X
170 @item raw PCM signed 8 bit @tab X @tab X
171 @item raw PCM signed 16 bit big-endian @tab X @tab X
172 @item raw PCM signed 16 bit little-endian @tab X @tab X
173 @item raw PCM signed 24 bit big-endian @tab X @tab X
174 @item raw PCM signed 24 bit little-endian @tab X @tab X
175 @item raw PCM signed 32 bit big-endian @tab X @tab X
176 @item raw PCM signed 32 bit little-endian @tab X @tab X
177 @item raw PCM unsigned 8 bit @tab X @tab X
178 @item raw PCM unsigned 16 bit big-endian @tab X @tab X
179 @item raw PCM unsigned 16 bit little-endian @tab X @tab X
180 @item raw PCM unsigned 24 bit big-endian @tab X @tab X
181 @item raw PCM unsigned 24 bit little-endian @tab X @tab X
182 @item raw PCM unsigned 32 bit big-endian @tab X @tab X
183 @item raw PCM unsigned 32 bit little-endian @tab X @tab X
184 @item raw PCM floating-point 32 bit big-endian @tab X @tab X
185 @item raw PCM floating-point 32 bit little-endian @tab X @tab X
186 @item raw PCM floating-point 64 bit big-endian @tab X @tab X
187 @item raw PCM floating-point 64 bit little-endian @tab X @tab X
188 @item RDT @tab @tab X
189 @item REDCODE R3D @tab @tab X
190 @tab File format used by RED Digital cameras, contains JPEG 2000 frames and PCM audio.
191 @item RealMedia @tab X @tab X
192 @item Redirector @tab @tab X
193 @item Renderware TeXture Dictionary @tab @tab X
194 @item RL2 @tab @tab X
195 @tab Audio and video format used in some games by Entertainment Software Partners.
196 @item RPL/ARMovie @tab @tab X
197 @item RTP @tab @tab X
198 @item RTSP @tab @tab X
199 @item SDP @tab @tab X
200 @item Sega FILM/CPK @tab @tab X
201 @tab Used in many Sega Saturn console games.
202 @item Sierra SOL @tab @tab X
203 @tab .sol files used in Sierra Online games.
204 @item Sierra VMD @tab @tab X
205 @tab Used in Sierra CD-ROM games.
206 @item Smacker @tab @tab X
207 @tab Multimedia format used by many games.
208 @item Sony OpenMG (OMA) @tab @tab X
209 @tab Audio format used in Sony Sonic Stage and Sony Vegas.
210 @item Sony PlayStation STR @tab @tab X
211 @item SUN AU format @tab X @tab X
212 @item THP @tab @tab X
213 @tab Used on the Nintendo GameCube.
214 @item Tiertex Limited SEQ @tab @tab X
215 @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
216 @item True Audio @tab @tab X
217 @item VC-1 test bitstream @tab X @tab X
218 @item WAV @tab X @tab X
219 @item WavPack @tab @tab X
220 @item Wing Commander III movie @tab @tab X
221 @tab Multimedia format used in Origin's Wing Commander III computer game.
222 @item Westwood Studios audio @tab @tab X
223 @tab Multimedia format used in Westwood Studios games.
224 @item Westwood Studios VQA @tab @tab X
225 @tab Multimedia format used in Westwood Studios games.
226 @item YUV4MPEG pipe @tab X @tab X
229 @code{X} means that encoding (resp. decoding) is supported.
231 @section Image Formats
233 FFmpeg can read and write images for each frame of a video sequence. The
234 following image formats are supported:
236 @multitable @columnfractions .4 .1 .1 .4
237 @item Name @tab Encoding @tab Decoding @tab Comments
238 @item .Y.U.V @tab X @tab X
239 @tab one raw file per component
240 @item animated GIF @tab X @tab X
241 @tab Only uncompressed GIFs are generated.
242 @item BMP @tab X @tab X
243 @tab Microsoft BMP image
244 @item JPEG @tab X @tab X
245 @tab Progressive JPEG is not supported.
246 @item JPEG 2000 @tab @tab E
247 @tab decoding supported through external library libopenjpeg
248 @item JPEG-LS @tab X @tab X
249 @item LJPEG @tab X @tab
251 @item PAM @tab X @tab X
252 @tab PAM is a PNM extension with alpha support.
253 @item PBM @tab X @tab X
254 @tab Portable BitMap image
255 @item PCX @tab X @tab X
257 @item PGM @tab X @tab X
258 @tab Portable GrayMap image
259 @item PGMYUV @tab X @tab X
260 @tab PGM with U and V components in YUV 4:2:0
261 @item PNG @tab X @tab X
262 @tab 2/4 bpp not supported yet
263 @item PPM @tab X @tab X
264 @tab Portable PixelMap image
265 @item PTX @tab @tab X
266 @tab V.Flash PTX format
267 @item SGI @tab X @tab X
268 @tab SGI RGB image format
269 @item Sun Rasterfile @tab @tab X
270 @tab Sun RAS image format
271 @item TIFF @tab X @tab X
272 @tab YUV, JPEG and some extension is not supported yet.
273 @item Truevision Targa @tab X @tab X
274 @tab Targa (.TGA) image format
277 @code{X} means that encoding (resp. decoding) is supported.
279 @code{E} means that support is provided through an external library.
281 @section Video Codecs
283 @multitable @columnfractions .4 .1 .1 .4
284 @item Name @tab Encoding @tab Decoding @tab Comments
285 @item 4X Movie @tab @tab X
286 @tab Used in certain computer games.
287 @item 8088flex TMV @tab @tab X
288 @item 8SVX exponential @tab @tab X
289 @item 8SVX fibonacci @tab @tab X
290 @item American Laser Games MM @tab @tab X
291 @tab Used in games like Mad Dog McCree.
292 @item AMV Video @tab @tab X
293 @tab Used in Chinese MP3 players.
294 @item Apple MJPEG-B @tab @tab X
295 @item Apple QuickDraw @tab @tab X
297 @item Asus v1 @tab X @tab X
299 @item Asus v2 @tab X @tab X
301 @item ATI VCR1 @tab @tab X
303 @item ATI VCR2 @tab @tab X
305 @item Autodesk Animator Flic video @tab @tab X
306 @item Autodesk RLE @tab @tab X
308 @item AVS (Audio Video Standard) video @tab @tab X
309 @tab Video encoding used by the Creature Shock game.
310 @item Beam Software VB @tab @tab X
311 @item Bethesda VID video @tab @tab X
312 @tab Used in some games from Bethesda Softworks.
313 @item Brute Force & Ignorance @tab @tab X
314 @tab Used in the game Flash Traffic: City of Angels.
315 @item C93 video @tab @tab X
316 @tab Codec used in Cyberia game.
317 @item CamStudio @tab @tab X
319 @item Chinese AVS video @tab @tab X
320 @tab AVS1-P2, JiZhun profile
321 @item Delphine Software International CIN video @tab @tab X
322 @tab Codec used in Delphine Software International games.
323 @item Cinepak @tab @tab X
324 @item Cirrus Logic AccuPak @tab @tab X
326 @item Creative YUV (CYUV) @tab @tab X
327 @item Dirac @tab E @tab E
328 @tab supported through external libdirac/libschroedinger libraries
329 @item DNxHD @tab X @tab X
331 @item Duck TrueMotion 1.0 @tab @tab X
333 @item Duck TrueMotion 2.0 @tab @tab X
335 @item DV (Digital Video) @tab X @tab X
336 @item Feeble Files/ScummVM DXA @tab @tab X
337 @tab Codec originally used in Feeble Files game.
338 @item Electronic Arts CMV video @tab @tab X
339 @tab Used in NHL 95 game.
340 @item Electronic Arts TGV video @tab @tab X
341 @item Electronic Arts TGQ video @tab @tab X
342 @item Electronic Arts TQI video @tab @tab X
343 @item Escape 124 @tab @tab X
344 @item FFmpeg codec #1 @tab X @tab X
345 @tab experimental lossless codec (fourcc: FFV1)
346 @item Flash Screen Video v1 @tab X @tab X
348 @item Flash Video (FLV) @tab X @tab X
349 @tab Sorenson H.263 used in Flash
350 @item Fraps @tab @tab X
351 @item H.261 @tab X @tab X
352 @item H.263 / H.263-1996 @tab X @tab X
353 @item H.263+ / H.263-1998 / H.263 version 2 @tab X @tab X
354 @item H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 @tab E @tab X
355 @tab encoding supported through external library libx264
356 @item H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (VDPAU acceleration) @tab E @tab X
357 @item HuffYUV @tab X @tab X
358 @item HuffYUV FFmpeg variant @tab X @tab X
359 @item IBM Ultimotion @tab @tab X
361 @item id Cinematic video @tab @tab X
362 @tab Used in Quake II.
363 @item id RoQ video @tab X @tab X
364 @tab Used in Quake III, Jedi Knight 2, other computer games.
365 @item Intel H.263 @tab @tab X
366 @item Intel Indeo 2 @tab @tab X
367 @item Intel Indeo 3 @tab @tab X
368 @item Interplay C93 @tab @tab X
369 @tab Used in the game Cyberia from Interplay.
370 @item Interplay MVE video @tab @tab X
371 @tab Used in Interplay .MVE files.
372 @item Karl Morton's video codec @tab @tab X
373 @tab Codec used in Worms games.
374 @item LCL (LossLess Codec Library) MSZH @tab @tab X
375 @item LCL (LossLess Codec Library) ZLIB @tab E @tab E
376 @item LOCO @tab @tab X
377 @item lossless MJPEG @tab X @tab X
378 @item Microsoft RLE @tab @tab X
379 @item Microsoft Video 1 @tab @tab X
380 @item Mimic @tab @tab X
381 @tab Used in MSN Messenger Webcam streams.
382 @item Miro VideoXL @tab @tab X
384 @item MJPEG (Motion JPEG) @tab X @tab X
385 @item Motion Pixels video @tab @tab X
386 @item MPEG-1 video @tab X @tab X
387 @item MPEG-1/2 video XvMC (X-Video Motion Compensation) @tab @tab X
388 @item MPEG-1/2 video (VDPAU acceleration) @tab @tab X
389 @item MPEG-2 video @tab X @tab X
390 @item MPEG-4 part 2 @tab X @tab X
391 @ libxvidcore can be used alternatively for encoding.
392 @item MPEG-4 part 2 Microsoft variant version 1 @tab X @tab X
393 @item MPEG-4 part 2 Microsoft variant version 2 @tab X @tab X
394 @item MPEG-4 part 2 Microsoft variant version 3 @tab X @tab X
395 @item Nintendo Gamecube THP video @tab @tab X
396 @item NuppelVideo/RTjpeg @tab @tab X
397 @tab Video encoding used in NuppelVideo files.
398 @item On2 VP3 @tab @tab X
399 @tab still experimental
400 @item On2 VP5 @tab @tab X
402 @item On2 VP6 @tab @tab X
403 @tab fourcc: VP60,VP61,VP62
404 @item planar RGB @tab @tab X
406 @item Q-team QPEG @tab @tab X
407 @tab fourccs: QPEG, Q1.0, Q1.1
408 @item QuickTime 8BPS video @tab @tab X
409 @item QuickTime Animation (RLE) video @tab X @tab X
411 @item QuickTime Graphics (SMC) @tab @tab X
413 @item QuickTime video (RPZA) @tab @tab X
415 @item Raw Video @tab X @tab X
416 @item RealVideo 1.0 @tab X @tab X
417 @item RealVideo 2.0 @tab X @tab X
418 @item RealVideo 3.0 @tab @tab X
419 @tab still far from ideal
420 @item RealVideo 4.0 @tab @tab X
421 @item Renderware TXD (TeXture Dictionary) @tab @tab X
422 @tab Texture dictionaries used by the Renderware Engine.
423 @item RL2 video @tab @tab X
424 @tab used in some games by Entertainment Software Partners
425 @item Sierra VMD video @tab @tab X
426 @tab Used in Sierra VMD files.
427 @item Smacker video @tab @tab X
428 @tab Video encoding used in Smacker.
429 @item SMPTE VC-1 @tab @tab X
430 @item Snow @tab X @tab X
431 @tab experimental wavelet codec (fourcc: SNOW)
432 @item Sony PlayStation MDEC (Motion DECoder) @tab @tab X
433 @item Sorenson Vector Quantizer 1 @tab X @tab X
435 @item Sorenson Vector Quantizer 3 @tab @tab X
437 @item Sunplus JPEG (SP5X) @tab @tab X
439 @item TechSmith Screen Capture Codec @tab @tab X
441 @item Theora @tab E @tab X
442 @tab encoding supported through external library libtheora
443 @item Tiertex Limited SEQ video @tab @tab X
444 @tab Codec used in DOS CD-ROM FlashBack game.
445 @item V210 Quicktime Uncompressed 4:2:2 10-bit @tab X @tab X
446 @item VMware Screen Codec / VMware Video @tab @tab X
447 @tab Codec used in videos captured by VMware.
448 @item Westwood Studios VQA (Vector Quantized Animation) video @tab @tab X
449 @item Windows Media Video 7 @tab X @tab X
450 @item Windows Media Video 8 @tab X @tab X
451 @item Windows Media Video 9 @tab @tab X
452 @tab not completely working
453 @item Wing Commander III / Xan @tab @tab X
454 @tab Used in Wing Commander III .MVE files.
455 @item Winnov WNV1 @tab @tab X
456 @item WMV7 @tab X @tab X
457 @item YAMAHA SMAF @tab X @tab X
458 @item ZLIB @tab X @tab X
459 @tab part of LCL, encoder experimental
460 @item Zip Motion Blocks Video @tab X @tab X
461 @tab Encoder works only in PAL8.
464 @code{X} means that encoding (resp. decoding) is supported.
466 @code{E} means that support is provided through an external library.
468 @section Audio Codecs
470 @multitable @columnfractions .4 .1 .1 .4
471 @item Name @tab Encoding @tab Decoding @tab Comments
472 @item 8SVX audio @tab @tab X
473 @item AAC @tab E @tab X
474 @tab encoding supported through external library libfaac
475 @item AC-3 @tab IX @tab X
476 @item ADPCM 4X Movie @tab @tab X
477 @item ADPCM CDROM XA @tab @tab X
478 @item ADPCM Creative Technology @tab @tab X
479 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
480 @item ADPCM Electronic Arts @tab @tab X
481 @tab Used in various EA titles.
482 @item ADPCM Electronic Arts Maxis CDROM XS @tab @tab X
483 @tab Used in Sim City 3000.
484 @item ADPCM Electronic Arts R1 @tab @tab X
485 @item ADPCM Electronic Arts R2 @tab @tab X
486 @item ADPCM Electronic Arts R3 @tab @tab X
487 @item ADPCM Electronic Arts XAS @tab @tab X
488 @item ADPCM G.726 @tab X @tab X
489 @item ADPCM IMA AMV @tab @tab X
490 @tab Used in AMV files
491 @item ADPCM IMA Electronic Arts EACS @tab @tab X
492 @item ADPCM IMA Electronic Arts SEAD @tab @tab X
493 @item ADPCM IMA Funcom @tab @tab X
494 @item ADPCM IMA QuickTime @tab X @tab X
495 @item ADPCM IMA Loki SDL MJPEG @tab @tab X
496 @item ADPCM IMA WAV @tab X @tab X
497 @item ADPCM IMA Westwood @tab @tab X
498 @item ADPCM ISS IMA @tab @tab X
499 @tab Used in FunCom games.
500 @item ADPCM IMA Duck DK3 @tab @tab X
501 @tab Used in some Sega Saturn console games.
502 @item ADPCM IMA Duck DK4 @tab @tab X
503 @tab Used in some Sega Saturn console games.
504 @item ADPCM Microsoft @tab X @tab X
505 @item ADPCM MS IMA @tab X @tab X
506 @item ADPCM Nintendo Gamecube THP @tab @tab X
507 @item ADPCM QT IMA @tab X @tab X
508 @item ADPCM SEGA CRI ADX @tab X @tab X
509 @tab Used in Sega Dreamcast games.
510 @item ADPCM Shockwave Flash @tab X @tab X
511 @item ADPCM SMJPEG IMA @tab @tab X
512 @tab Used in certain Loki game ports.
513 @item ADPCM Sound Blaster Pro 2-bit @tab @tab X
514 @item ADPCM Sound Blaster Pro 2.6-bit @tab @tab X
515 @item ADPCM Sound Blaster Pro 4-bit @tab @tab X
516 @item ADPCM Westwood Studios IMA @tab @tab X
517 @tab Used in Westwood Studios games like Command and Conquer.
518 @item ADPCM Yamaha @tab X @tab X
519 @item AMR-NB @tab E @tab E
520 @tab supported through external library libamrnb
521 @item AMR-WB @tab E @tab E
522 @tab supported through external library libamrwb
523 @item Apple lossless audio @tab X @tab X
524 @tab QuickTime fourcc 'alac'
525 @item Atrac 3 @tab @tab X
526 @item Delphine Software International CIN audio @tab @tab X
527 @tab Codec used in Delphine Software International games.
528 @item COOK @tab @tab X
529 @tab All versions except 5.1 are supported.
530 @item DCA (DTS Coherent Acoustics) @tab @tab X
531 @item DPCM id RoQ @tab X @tab X
532 @tab Used in Quake III, Jedi Knight 2, other computer games.
533 @item DPCM Interplay @tab @tab X
534 @tab Used in various Interplay computer games.
535 @item DPCM Sierra Online @tab @tab X
536 @tab Used in Sierra Online game audio files.
537 @item DPCM Sol @tab @tab X
538 @item DPCM Xan @tab @tab X
539 @item DSP Group TrueSpeech @tab @tab X
540 @item DV audio @tab @tab X
541 @item Enhanced AC-3 @tab @tab X
542 @item FLAC (Free Lossless Audio Codec) @tab X @tab IX
543 @item G.729 @tab @tab X
544 @item GSM @tab E @tab E
545 @tab supported through external library libgsm
546 @item GSM Microsoft variant @tab E @tab E
547 @tab supported through external library libgsm
548 @item IMC (Intel Music Coder) @tab @tab X
549 @item MACE (Macintosh Audio Compression/Expansion) 3:1 @tab @tab X
550 @item MACE (Macintosh Audio Compression/Expansion) 6:1 @tab @tab X
551 @item MLP (Meridian Lossless Packing) @tab @tab X
552 @tab Used in DVD-Audio discs.
553 @item Monkey's Audio @tab @tab X
554 @tab Only versions 3.97-3.99 are supported.
555 @item MP1 (MPEG audio layer 1) @tab @tab IX
556 @item MP2 (MPEG audio layer 2) @tab IX @tab IX
557 @item MP3 (MPEG audio layer 3) @tab E @tab IX
558 @tab encoding supported through external library LAME, ADU MP3 and MP3onMP4 also supported
559 @item Musepack SV7 @tab @tab X
560 @item Musepack SV8 @tab @tab X
561 @item Nellymoser Asao @tab X @tab X
562 @item PCM A-law @tab X @tab X
563 @item PCM mu-law @tab X @tab X
564 @item PCM 16-bit little-endian planar @tab @tab X
565 @item PCM 32-bit floating point big-endian @tab X @tab X
566 @item PCM 32-bit floating point little-endian @tab X @tab X
567 @item PCM 64-bit floating point big-endian @tab X @tab X
568 @item PCM 64-bit floating point little-endian @tab X @tab X
569 @item PCM D-Cinema audio signed 24-bit @tab X @tab X
570 @item PCM signed 8-bit @tab X @tab X
571 @item PCM signed 16-bit big-endian @tab X @tab X
572 @item PCM signed 16-bit little-endian @tab X @tab X
573 @item PCM signed 24-bit big-endian @tab X @tab X
574 @item PCM signed 24-bit little-endian @tab X @tab X
575 @item PCM signed 32-bit big-endian @tab X @tab X
576 @item PCM signed 32-bit little-endian @tab X @tab X
577 @item PCM unsigned 8-bit @tab X @tab X
578 @item PCM unsigned 16-bit big-endian @tab X @tab X
579 @item PCM unsigned 16-bit little-endian @tab X @tab X
580 @item PCM unsigned 24-bit big-endian @tab X @tab X
581 @item PCM unsigned 24-bit little-endian @tab X @tab X
582 @item PCM unsigned 32-bit big-endian @tab X @tab X
583 @item PCM unsigned 32-bit little-endian @tab X @tab X
584 @item PCM Zork @tab X @tab X
585 @item QCELP / PureVoice @tab @tab X
586 @item QDesign Music Codec 2 @tab @tab X
587 @tab There are still some distortions.
588 @item RealAudio 1.0 (14.4K) @tab @tab X
589 @tab Real 14400 bit/s codec
590 @item RealAudio 2.0 (28.8K) @tab @tab X
591 @tab Real 28800 bit/s codec
592 @item RealAudio 3.0 (dnet) @tab IX @tab X
593 @tab Real low bitrate AC-3 codec
594 @item Shorten @tab @tab X
595 @item Sierra VMD audio @tab @tab X
596 @tab Used in Sierra VMD files.
597 @item Smacker audio @tab @tab X
598 @item Sonic @tab X @tab X
599 @tab experimental codec
600 @item Sonic lossless @tab X @tab X
601 @tab experimental codec
602 @item Speex @tab @tab E
603 @tab supported through external library libspeex
604 @item True Audio (TTA) @tab @tab X
605 @item TrueHD @tab @tab X
606 @tab Used in HD-DVD and Blu-Ray discs.
607 @item Vorbis @tab E @tab X
608 @ A native but very primitive encoder exists.
609 @item WavPack @tab @tab X
610 @item Westwood Audio (SND1) @tab @tab X
611 @item Windows Media Audio 1 @tab X @tab X
612 @item Windows Media Audio 2 @tab X @tab X
613 @tab Used in Origin's Wing Commander IV AVI files.
616 @code{X} means that encoding (resp. decoding) is supported.
618 @code{E} means that support is provided through an external library.
620 @code{I} means that an integer-only version is available, too (ensures high
621 performance on systems without hardware floating point support).
623 @section Subtitle Formats
625 @multitable @columnfractions .4 .1 .1 .1 .1
626 @item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding
627 @item SSA/ASS @tab X @tab X
628 @item DVB @tab X @tab X @tab X @tab X
629 @item DVD @tab X @tab X @tab X @tab X
630 @item XSUB @tab @tab @tab @tab X
633 @code{X} means that the feature is supported.
635 @section Network Protocols
637 @multitable @columnfractions .4 .1
638 @item Name @tab Support
648 @code{X} means that the protocol is supported.
651 @section Input/Output Devices
653 @multitable @columnfractions .4 .1 .1
654 @item Name @tab Input @tab Output
655 @item ALSA @tab X @tab X
656 @item BEOS audio @tab X @tab X
657 @item BKTR @tab X @tab
658 @item DV1394 @tab X @tab
659 @item JACK @tab X @tab
660 @item LIBDC1394 @tab X @tab
661 @item OSS @tab X @tab X
662 @item Video4Linux @tab X @tab
663 @item Video4Linux2 @tab X @tab
664 @item VfW capture @tab X @tab
665 @item X11 grabbing @tab X @tab
668 @code{X} means that input/output is supported.
671 @chapter Platform Specific information
675 BSD make will not build FFmpeg, you need to install and use GNU Make
680 To get help and instructions for building FFmpeg under Windows, check out
681 the FFmpeg Windows Help Forum at
682 @url{http://ffmpeg.arrozcru.org/}.
684 @subsection Native Windows compilation
686 FFmpeg can be built to run natively on Windows using the MinGW tools. Install
687 the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
688 You can find detailed installation
689 instructions in the download section and the FAQ.
691 FFmpeg does not build out-of-the-box with the packages the automated MinGW
692 installer provides. It also requires coreutils to be installed and many other
693 packages updated to the latest version. The minimum version for some packages
698 @item msys-make 3.81-2 (note: not mingw32-make)
700 @item mingw-runtime 3.15
703 FFmpeg automatically passes @code{-fno-common} to the compiler to work around
704 a GCC bug (see @url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216}).
706 Within the MSYS shell, configure and make with:
709 ./configure --enable-memalign-hack --extra-cflags=-fno-common
714 This will install @file{ffmpeg.exe} along with many other development files
715 to @file{/usr/local}. You may specify another install path using the
716 @code{--prefix} option in @file{configure}.
722 @item In order to compile FFplay, you must have the MinGW development library
723 of SDL. Get it from @url{http://www.libsdl.org}.
724 Edit the @file{bin/sdl-config} script so that it points to the correct prefix
725 where SDL was installed. Verify that @file{sdl-config} can be launched from
726 the MSYS command line.
728 @item By using @code{./configure --enable-shared} when configuring FFmpeg,
729 you can build libavutil, libavcodec and libavformat as DLLs.
733 @subsection Microsoft Visual C++ compatibility
735 As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
736 want to use the libav* libraries in your own applications, you can still
737 compile those applications using MSVC++. But the libav* libraries you link
738 to @emph{must} be built with MinGW. However, you will not be able to debug
739 inside the libav* libraries, since MSVC++ does not recognize the debug
740 symbols generated by GCC.
741 We strongly recommend you to move over from MSVC++ to MinGW tools.
743 This description of how to use the FFmpeg libraries with MSVC++ is based on
744 Microsoft Visual C++ 2005 Express Edition. If you have a different version,
745 you might have to modify the procedures slightly.
747 @subsubsection Using static libraries
749 Assuming you have just built and installed FFmpeg in @file{/usr/local}.
753 @item Create a new console application ("File / New / Project") and then
754 select "Win32 Console Application". On the appropriate page of the
755 Application Wizard, uncheck the "Precompiled headers" option.
757 @item Write the source code for your application, or, for testing, just
758 copy the code from an existing sample application into the source file
759 that MSVC++ has already created for you. For example, you can copy
760 @file{libavformat/output-example.c} from the FFmpeg distribution.
762 @item Open the "Project / Properties" dialog box. In the "Configuration"
763 combo box, select "All Configurations" so that the changes you make will
764 affect both debug and release builds. In the tree view on the left hand
765 side, select "C/C++ / General", then edit the "Additional Include
766 Directories" setting to contain the path where the FFmpeg includes were
767 installed (i.e. @file{c:\msys\1.0\local\include}).
768 Do not add MinGW's include directory here, or the include files will
769 conflict with MSVC's.
771 @item Still in the "Project / Properties" dialog box, select
772 "Linker / General" from the tree view and edit the
773 "Additional Library Directories" setting to contain the @file{lib}
774 directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
775 the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
776 and the directory where MinGW's GCC libs are installed
777 (i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
778 "Linker / Input" from the tree view, and add the files @file{libavformat.a},
779 @file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
780 @file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
781 to the end of "Additional Dependencies".
783 @item Now, select "C/C++ / Code Generation" from the tree view. Select
784 "Debug" in the "Configuration" combo box. Make sure that "Runtime
785 Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
786 the "Configuration" combo box and make sure that "Runtime Library" is
787 set to "Multi-threaded DLL".
789 @item Click "OK" to close the "Project / Properties" dialog box.
791 @item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
792 Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
793 and install it in MSVC++'s include directory
794 (i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
796 @item MSVC++ also does not understand the @code{inline} keyword used by
797 FFmpeg, so you must add this line before @code{#include}ing libav*:
799 #define inline _inline
802 @item Build your application, everything should work.
806 @subsubsection Using shared libraries
808 This is how to create DLL and LIB files that are compatible with MSVC++:
812 @item Add a call to @file{vcvars32.bat} (which sets up the environment
813 variables for the Visual C++ tools) as the first line of @file{msys.bat}.
814 The standard location for @file{vcvars32.bat} is
815 @file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
816 and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
817 If this corresponds to your setup, add the following line as the first line
821 call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
824 Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
825 and run @file{c:\msys\1.0\msys.bat} from there.
827 @item Within the MSYS shell, run @code{lib.exe}. If you get a help message
828 from @file{Microsoft (R) Library Manager}, this means your environment
829 variables are set up correctly, the @file{Microsoft (R) Library Manager}
830 is on the path and will be used by FFmpeg to create
831 MSVC++-compatible import libraries.
833 @item Build FFmpeg with
836 ./configure --enable-shared --enable-memalign-hack
841 Your install path (@file{/usr/local/} by default) should now have the
842 necessary DLL and LIB files under the @file{bin} directory.
846 To use those files with MSVC++, do the same as you would do with
847 the static libraries, as described above. But in Step 4,
848 you should only need to add the directory where the LIB files are installed
849 (i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
850 installed in the @file{bin} directory. And instead of adding @file{libxx.a}
851 files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
852 @file{avutil.lib}. There should be no need for @file{libmingwex.a},
853 @file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
854 statically linked into the DLLs. The @file{bin} directory contains a bunch
855 of DLL files, but the ones that are actually used to run your application
856 are the ones with a major version number in their filenames
857 (i.e. @file{avcodec-51.dll}).
859 @subsection Cross compilation for Windows with Linux
861 You must use the MinGW cross compilation tools available at
862 @url{http://www.mingw.org/}.
864 Then configure FFmpeg with the following options:
866 ./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
868 (you can change the cross-prefix according to the prefix chosen for the
871 Then you can easily test FFmpeg with Wine
872 (@url{http://www.winehq.com/}).
874 @subsection Compilation under Cygwin
876 The main issue with the 1.5.x Cygwin versions is that newlib, its C library,
877 does not contain llrint(). You need to upgrade to the unstable 1.7.x versions,
878 or leverage the implementation in MinGW (as explained below).
880 Just install your Cygwin with all the "Base" packages, plus the
881 following "Devel" ones:
883 binutils, gcc-core, make, subversion, mingw-runtime, diffutils
886 The experimental gcc4 package is still buggy, hence please
887 use the official gcc 3.4.4 or a 4.2.x compiled from source by yourself.
889 Install the current binutils-20080624-2 as they work fine (the old
890 binutils-20060709-1 proved buggy on shared builds).
892 Then create a small library that just contains llrint():
895 ar x /usr/lib/mingw/libmingwex.a llrint.o
896 ar cq /usr/local/lib/libllrint.a llrint.o
902 ./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
905 to make a static build or
908 ./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
911 to build shared libraries.
913 If you want to build FFmpeg with additional libraries, download Cygwin
914 "Devel" packages for Ogg and Vorbis from any Cygwin packages repository:
916 libogg-devel, libvorbis-devel
919 These library packages are only available from Cygwin Ports
920 (@url{http://sourceware.org/cygwinports/}) :
923 yasm, libSDL-devel, libdirac-devel, libfaac-devel, libfaad-devel, libgsm-devel,
924 libmp3lame-devel, libschroedinger1.0-devel, speex-devel, libtheora-devel,
928 The recommendation for libnut and x264 is to build them from source by
929 yourself, as they evolve too quickly for Cygwin Ports to be up to date.
931 Cygwin 1.7.x has IPv6 support. You can add IPv6 to Cygwin 1.5.x by means
932 of the @code{libgetaddrinfo-devel} package, available at Cygwin Ports.
934 @subsection Crosscompilation for Windows under Cygwin
936 With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
938 Just install your Cygwin as explained before, plus these additional
941 gcc-mingw-core, mingw-runtime, mingw-zlib
944 and add some special flags to your configure invocation.
946 For a static build run
948 ./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
951 and for a build with shared libraries
953 ./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
958 BeOS support is broken in mysterious ways.
962 For information about compiling FFmpeg on OS/2 see
963 @url{http://www.edm2.com/index.php/FFmpeg}.
965 @chapter Developers Guide
969 @item libavcodec is the library containing the codecs (both encoding and
970 decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
972 @item libavformat is the library containing the file format handling (mux and
973 demux code for several formats). Look at @file{ffplay.c} to use it in a
974 player. See @file{libavformat/output-example.c} to use it to generate
975 audio or video streams.
979 @section Integrating libavcodec or libavformat in your program
981 You can integrate all the source code of the libraries to link them
982 statically to avoid any version problem. All you need is to provide a
983 'config.mak' and a 'config.h' in the parent directory. See the defines
984 generated by ./configure to understand what is needed.
986 You can use libavcodec or libavformat in your commercial program, but
987 @emph{any patch you make must be published}. The best way to proceed is
988 to send your patches to the FFmpeg mailing list.
991 @section Coding Rules
993 FFmpeg is programmed in the ISO C90 language with a few additional
994 features from ISO C99, namely:
997 the @samp{inline} keyword;
1001 designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
1003 compound literals (@samp{x = (struct s) @{ 17, 23 @};})
1006 These features are supported by all compilers we care about, so we will not
1007 accept patches to remove their use unless they absolutely do not impair
1008 clarity and performance.
1010 All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
1011 compiles with several other compilers, such as the Compaq ccc compiler
1012 or Sun Studio 9, and we would like to keep it that way unless it would
1013 be exceedingly involved. To ensure compatibility, please do not use any
1014 additional C99 features or GCC extensions. Especially watch out for:
1017 mixing statements and declarations;
1019 @samp{long long} (use @samp{int64_t} instead);
1021 @samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
1023 GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
1027 The presentation is the one specified by 'indent -i4 -kr -nut'.
1028 The TAB character is forbidden outside of Makefiles as is any
1029 form of trailing whitespace. Commits containing either will be
1030 rejected by the Subversion repository.
1032 The main priority in FFmpeg is simplicity and small code size in order to
1033 minimize the bug count.
1035 Comments: Use the JavaDoc/Doxygen
1036 format (see examples below) so that code documentation
1037 can be generated automatically. All nontrivial functions should have a comment
1038 above them explaining what the function does, even if it is just one sentence.
1039 All structures and their member variables should be documented, too.
1052 typedef struct Foobar@{
1053 int var1; /**< var1 description */
1054 int var2; ///< var2 description
1055 /** var3 description */
1063 * @@param my_parameter description of my_parameter
1064 * @@return return value description
1066 int myfunc(int my_parameter)
1070 fprintf and printf are forbidden in libavformat and libavcodec,
1071 please use av_log() instead.
1073 Casts should be used only when necessary. Unneeded parentheses
1074 should also be avoided if they don't make the code easier to understand.
1076 @section Development Policy
1080 Contributions should be licensed under the LGPL 2.1, including an
1081 "or any later version" clause, or the MIT license. GPL 2 including
1082 an "or any later version" clause is also acceptable, but LGPL is
1085 You must not commit code which breaks FFmpeg! (Meaning unfinished but
1086 enabled code which breaks compilation or compiles but does not work or
1087 breaks the regression tests)
1088 You can commit unfinished stuff (for testing etc), but it must be disabled
1089 (#ifdef etc) by default so it does not interfere with other developers'
1092 You do not have to over-test things. If it works for you, and you think it
1093 should work for others, then commit. If your code has problems
1094 (portability, triggers compiler bugs, unusual environment etc) they will be
1095 reported and eventually fixed.
1097 Do not commit unrelated changes together, split them into self-contained
1098 pieces. Also do not forget that if part B depends on part A, but A does not
1099 depend on B, then A can and should be committed first and separate from B.
1100 Keeping changes well split into self-contained parts makes reviewing and
1101 understanding them on the commit log mailing list easier. This also helps
1102 in case of debugging later on.
1103 Also if you have doubts about splitting or not splitting, do not hesitate to
1104 ask/discuss it on the developer mailing list.
1106 Do not change behavior of the program (renaming options etc) without
1107 first discussing it on the ffmpeg-devel mailing list. Do not remove
1108 functionality from the code. Just improve!
1110 Note: Redundant code can be removed.
1112 Do not commit changes to the build system (Makefiles, configure script)
1113 which change behavior, defaults etc, without asking first. The same
1114 applies to compiler warning fixes, trivial looking fixes and to code
1115 maintained by other developers. We usually have a reason for doing things
1116 the way we do. Send your changes as patches to the ffmpeg-devel mailing
1117 list, and if the code maintainers say OK, you may commit. This does not
1118 apply to files you wrote and/or maintain.
1120 We refuse source indentation and other cosmetic changes if they are mixed
1121 with functional changes, such commits will be rejected and removed. Every
1122 developer has his own indentation style, you should not change it. Of course
1123 if you (re)write something, you can use your own style, even though we would
1124 prefer if the indentation throughout FFmpeg was consistent (Many projects
1125 force a given indentation style - we do not.). If you really need to make
1126 indentation changes (try to avoid this), separate them strictly from real
1129 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1130 then either do NOT change the indentation of the inner part within (do not
1131 move it to the right)! or do so in a separate commit
1133 Always fill out the commit log message. Describe in a few lines what you
1134 changed and why. You can refer to mailing list postings if you fix a
1135 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1137 If you apply a patch by someone else, include the name and email address in
1138 the log message. Since the ffmpeg-cvslog mailing list is publicly
1139 archived you should add some SPAM protection to the email address. Send an
1140 answer to ffmpeg-devel (or wherever you got the patch from) saying that
1141 you applied the patch.
1143 When applying patches that have been discussed (at length) on the mailing
1144 list, reference the thread in the log message.
1146 Do NOT commit to code actively maintained by others without permission.
1147 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
1148 timeframe (12h for build failures and security fixes, 3 days small changes,
1149 1 week for big patches) then commit your patch if you think it is OK.
1150 Also note, the maintainer can simply ask for more time to review!
1152 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1153 are sent there and reviewed by all the other developers. Bugs and possible
1154 improvements or general questions regarding commits are discussed there. We
1155 expect you to react if problems with your code are uncovered.
1157 Update the documentation if you change behavior or add features. If you are
1158 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1159 maintainer(s) will review and commit your stuff.
1161 Try to keep important discussions and requests (also) on the public
1162 developer mailing list, so that all developers can benefit from them.
1164 Never write to unallocated memory, never write over the end of arrays,
1165 always check values read from some untrusted source before using them
1166 as array index or other risky things.
1168 Remember to check if you need to bump versions for the specific libav
1169 parts (libavutil, libavcodec, libavformat) you are changing. You need
1170 to change the version integer.
1171 Incrementing the first component means no backward compatibility to
1172 previous versions (e.g. removal of a function from the public API).
1173 Incrementing the second component means backward compatible change
1174 (e.g. addition of a function to the public API or extension of an
1175 existing data structure).
1176 Incrementing the third component means a noteworthy binary compatible
1177 change (e.g. encoder bug fix that matters for the decoder).
1179 Compiler warnings indicate potential bugs or code with bad style. If a type of
1180 warning always points to correct and clean code, that warning should
1181 be disabled, not the code changed.
1182 Thus the remaining warnings can either be bugs or correct code.
1183 If it is a bug, the bug has to be fixed. If it is not, the code should
1184 be changed to not generate a warning unless that causes a slowdown
1185 or obfuscates the code.
1187 If you add a new file, give it a proper license header. Do not copy and
1188 paste it from a random place, use an existing file as template.
1191 We think our rules are not too hard. If you have comments, contact us.
1193 Note, these rules are mostly borrowed from the MPlayer project.
1195 @section Submitting patches
1197 First, (@pxref{Coding Rules}) above if you did not yet.
1199 When you submit your patch, try to send a unified diff (diff '-up'
1200 option). We cannot read other diffs :-)
1202 Also please do not submit a patch which contains several unrelated changes.
1203 Split it into separate, self-contained pieces. This does not mean splitting
1204 file by file. Instead, make the patch as small as possible while still
1205 keeping it as a logical unit that contains an individual change, even
1206 if it spans multiple files. This makes reviewing your patches much easier
1207 for us and greatly increases your chances of getting your patch applied.
1209 Run the regression tests before submitting a patch so that you can
1210 verify that there are no big problems.
1212 Patches should be posted as base64 encoded attachments (or any other
1213 encoding which ensures that the patch will not be trashed during
1214 transmission) to the ffmpeg-devel mailing list, see
1215 @url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1217 It also helps quite a bit if you tell us what the patch does (for example
1218 'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1219 and has no lrint()')
1221 Also please if you send several patches, send each patch as a separate mail,
1222 do not attach several unrelated patches to the same mail.
1224 @section New codecs or formats checklist
1228 Did you use av_cold for codec initialization and close functions?
1230 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
1231 AVInputFormat/AVOutputFormat struct?
1233 Did you bump the minor version number in @file{avcodec.h} or
1236 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
1238 Did you add the CodecID to @file{avcodec.h}?
1240 If it has a fourcc, did you add it to @file{libavformat/riff.c},
1241 even if it is only a decoder?
1243 Did you add a rule to compile the appropriate files in the Makefile?
1244 Remember to do this even if you're just adding a format to a file that is
1245 already being compiled by some other rule, like a raw demuxer.
1247 Did you add an entry to the table of supported formats or codecs in the
1250 Did you add an entry in the Changelog?
1252 If it depends on a parser or a library, did you add that dependency in
1255 Did you "svn add" the appropriate files before commiting?
1258 @section patch submission checklist
1262 Do the regression tests pass with the patch applied?
1264 Does @code{make checkheaders} pass with the patch applied?
1266 Is the patch a unified diff?
1268 Is the patch against latest FFmpeg SVN?
1270 Are you subscribed to ffmpeg-dev?
1271 (the list is subscribers only due to spam)
1273 Have you checked that the changes are minimal, so that the same cannot be
1274 achieved with a smaller patch and/or simpler final code?
1276 If the change is to speed critical code, did you benchmark it?
1278 If you did any benchmarks, did you provide them in the mail?
1280 Have you checked that the patch does not introduce buffer overflows or
1281 other security issues?
1283 Did you test your decoder or demuxer against damaged data? If no, see
1284 tools/trasher and the noise bitstream filter. Your decoder or demuxer
1285 should not crash or end in a (near) infinite loop when fed damaged data.
1287 Is the patch created from the root of the source tree, so it can be
1288 applied with @code{patch -p0}?
1290 Does the patch not mix functional and cosmetic changes?
1292 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1294 Is the patch attached to the email you send?
1296 Is the mime type of the patch correct? It should be text/x-diff or
1297 text/x-patch or at least text/plain and not application/octet-stream.
1299 If the patch fixes a bug, did you provide a verbose analysis of the bug?
1301 If the patch fixes a bug, did you provide enough information, including
1302 a sample, so the bug can be reproduced and the fix can be verified?
1303 Note please do not attach samples >100k to mails but rather provide a
1304 URL, you can upload to ftp://upload.ffmpeg.org
1306 Did you provide a verbose summary about what the patch does change?
1308 Did you provide a verbose explanation why it changes things like it does?
1310 Did you provide a verbose summary of the user visible advantages and
1311 disadvantages if the patch is applied?
1313 Did you provide an example so we can verify the new feature added by the
1316 If you added a new file, did you insert a license header? It should be
1317 taken from FFmpeg, not randomly copied and pasted from somewhere else.
1319 You should maintain alphabetical order in alphabetically ordered lists as
1320 long as doing so does not break API/ABI compatibility.
1322 Lines with similar content should be aligned vertically when doing so
1323 improves readability.
1325 Did you provide a suggestion for a clear commit log message?
1328 @section Patch review process
1330 All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1331 clear note that the patch is not for SVN.
1332 Reviews and comments will be posted as replies to the patch on the
1333 mailing list. The patch submitter then has to take care of every comment,
1334 that can be by resubmitting a changed patch or by discussion. Resubmitted
1335 patches will themselves be reviewed like any other patch. If at some point
1336 a patch passes review with no comments then it is approved, that can for
1337 simple and small patches happen immediately while large patches will generally
1338 have to be changed and reviewed many times before they are approved.
1339 After a patch is approved it will be committed to the repository.
1341 We will review all submitted patches, but sometimes we are quite busy so
1342 especially for large patches this can take several weeks.
1344 When resubmitting patches, please do not make any significant changes
1345 not related to the comments received during review. Such patches will
1346 be rejected. Instead, submit significant changes or new features as
1349 @section Regression tests
1351 Before submitting a patch (or committing to the repository), you should at least
1352 test that you did not break anything.
1354 The regression tests build a synthetic video stream and a synthetic
1355 audio stream. These are then encoded and decoded with all codecs or
1356 formats. The CRC (or MD5) of each generated file is recorded in a
1357 result file. A 'diff' is launched to compare the reference results and
1360 The regression tests then go on to test the FFserver code with a
1361 limited set of streams. It is important that this step runs correctly
1364 Run 'make test' to test all the codecs and formats.
1366 Run 'make fulltest' to test all the codecs, formats and FFserver.
1368 [Of course, some patches may change the results of the regression tests. In
1369 this case, the reference results of the regression tests shall be modified