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 ADTS AAC audio @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 ASF @tab X @tab X
50 @item AVI @tab X @tab X
51 @item AVM2 (Flash 9) @tab X @tab X
52 @tab Only embedded audio is decoded.
54 @tab Multimedia format used by the Creature Shock game.
55 @item Bethsoft VID @tab @tab X
56 @tab Used in some games from Bethesda Softworks.
58 @tab Brute Force & Ignorance, used in Flash Traffic: City of Angels.
60 @tab Used in the game Cyberia from Interplay.
62 @tab Multimedia format used by Delphine Software games.
63 @item Creative VOC @tab X @tab X
64 @tab Created for the Sound Blaster Pro.
65 @item CRYO APC @tab @tab X
66 @tab Audio format used in some games by CRYO Interactive Entertainment.
67 @item DV @tab X @tab X
69 @tab This format is used in the non-Windows version of the Feeble Files
70 game and different game cutscenes repacked for use with ScummVM.
71 @item Electronic Arts Multimedia @tab @tab X
72 @tab Used in various EA games; files have extensions like WVE and UV2.
73 @item FLIC @tab @tab X
75 @item FLV @tab X @tab X
76 @tab Macromedia Flash video files
77 @item GXF @tab X @tab X
78 @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley
80 @item id Cinematic @tab @tab X
81 @tab Used in Quake II.
82 @item id RoQ @tab X @tab X
83 @tab Used in Quake III, Jedi Knight 2, other computer games.
85 @tab Interchange File Format
86 @item Interplay MVE @tab @tab X
87 @tab Format used in various Interplay computer games.
88 @item LMLM4 @tab @tab X
89 @tab Used by Linux Media Labs MPEG-4 PCI boards
90 @item Matroska @tab X @tab X
91 @item MAXIS EA XA @tab @tab X
92 @tab Used in Sim City 3000; file extension .xa.
93 @item Monkey's Audio @tab @tab X
94 @item Motion Pixels MVI @tab @tab X
95 @item MOV/QuickTime @tab X @tab X
96 @item MPEG audio @tab X @tab X
97 @item MPEG-1 systems @tab X @tab X
98 @tab muxed audio and video
99 @item MPEG-2 PS @tab X @tab X
100 @tab also known as @code{VOB} file
101 @item MPEG-2 TS @tab @tab X
102 @tab also known as DVB Transport Stream
103 @item MPEG-4 @tab X @tab X
104 @tab MPEG-4 is a variant of QuickTime.
105 @item MSN TCP webcam @tab @tab X
106 @tab Used by MSN Messenger webcam streams.
107 @item MXF @tab X @tab X
108 @tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
109 @item Nullsoft Video @tab @tab X
110 @item NUT @tab X @tab X
111 @tab NUT Open Container Format
112 @item OMA @tab @tab X
113 @tab Audio format used in Sony Sonic Stage and Sony Vegas.
114 @item PlayStation STR @tab @tab X
115 @item PVA @tab @tab X
116 @tab Used by TechnoTrend DVB PCI boards.
117 @item raw AC-3 @tab X @tab X
118 @item raw CRI ADX audio @tab X @tab X
119 @item raw MJPEG @tab X @tab X
120 @item raw MPEG video @tab X @tab X
121 @item raw MPEG-4 video @tab X @tab X
122 @item raw PCM 8/16/32 bits, 32/64-bit floating point, mu-law/A-law @tab X @tab X
123 @item raw Shorten audio @tab @tab X
124 @item RealMedia @tab X @tab X
125 @item RL2 @tab @tab X
126 @tab Audio and video format used in some games by Entertainment Software Partners.
127 @item Sega FILM/CPK @tab @tab X
128 @tab Used in many Sega Saturn console games.
129 @item SEQ @tab @tab X
130 @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
131 @item Sierra Online @tab @tab X
132 @tab .sol files used in Sierra Online games.
133 @item Sierra VMD @tab @tab X
134 @tab Used in Sierra CD-ROM games.
135 @item SIFF @tab @tab X
136 @tab Audio and video format used in some games by Beam Software.
137 @item Smacker @tab @tab X
138 @tab Multimedia format used by many games.
139 @item SUN AU format @tab X @tab X
140 @item THP @tab @tab X
141 @tab Used on the Nintendo GameCube.
142 @item WAV @tab X @tab X
143 @item WC3 Movie @tab @tab X
144 @tab Multimedia format used in Origin's Wing Commander III computer game.
145 @item Westwood Studios VQA/AUD @tab @tab X
146 @tab Multimedia formats used in Westwood Studios games.
149 @code{X} means that encoding (resp. decoding) is supported.
151 @section Image Formats
153 FFmpeg can read and write images for each frame of a video sequence. The
154 following image formats are supported:
156 @multitable @columnfractions .4 .1 .1 .4
157 @item Name @tab Encoding @tab Decoding @tab Comments
158 @item .Y.U.V @tab X @tab X @tab one raw file per component
159 @item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
160 @item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
161 @item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
162 @item PCX @tab @tab X @tab PC Paintbrush
163 @item PGM, PPM @tab X @tab X
164 @item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
165 @item PNG @tab X @tab X @tab 2/4 bpp not supported yet
166 @item PTX @tab @tab X @tab V.Flash PTX format
167 @item RAS @tab @tab X @tab Sun Rasterfile
168 @item SGI @tab X @tab X @tab SGI RGB image format
169 @item Targa @tab @tab X @tab Targa (.TGA) image format
170 @item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
173 @code{X} means that encoding (resp. decoding) is supported.
175 @section Video Codecs
177 @multitable @columnfractions .4 .1 .1 .4
178 @item Name @tab Encoding @tab Decoding @tab Comments
179 @item 4X Video @tab @tab X
180 @tab Used in certain computer games.
181 @item American Laser Games Video @tab @tab X
182 @tab Used in games like Mad Dog McCree.
183 @item AMV @tab @tab X
184 @tab Used in Chinese MP3 players.
185 @item Apple Animation @tab X @tab X
187 @item Apple Graphics @tab @tab X
189 @item Apple MJPEG-B @tab @tab X
190 @item Apple QuickDraw @tab @tab X
192 @item Apple Video @tab @tab X
194 @item Asus v1 @tab X @tab X
196 @item Asus v2 @tab X @tab X
198 @item ATI VCR1 @tab @tab X
200 @item ATI VCR2 @tab @tab X
202 @item Autodesk RLE @tab @tab X
204 @item AVID DNxHD @tab X @tab X
206 @item AVS video @tab @tab X
207 @tab Video encoding used by the Creature Shock game.
208 @item Bethsoft VID @tab @tab X
209 @tab Used in some games from Bethesda Softworks.
210 @item C93 video @tab @tab X
211 @tab Codec used in Cyberia game.
212 @item CamStudio @tab @tab X
214 @item Cin video @tab @tab X
215 @tab Codec used in Delphine Software games.
216 @item Cinepak @tab @tab X
217 @item Cirrus Logic AccuPak @tab @tab X
219 @item Creative YUV @tab @tab X
221 @item Dirac @tab X @tab X
222 @tab Supported through the external libdirac/libschroedinger libraries.
223 @item Duck TrueMotion v1 @tab @tab X
225 @item Duck TrueMotion v2 @tab @tab X
227 @item DV @tab X @tab X
228 @item DXA Video @tab @tab X
229 @tab Codec originally used in Feeble Files game.
230 @item Electronic Arts CMV @tab @tab X
231 @tab Used in NHL 95 game.
232 @item Electronic Arts TGV @tab @tab X
233 @item FFmpeg Video 1 @tab X @tab X
234 @tab experimental lossless codec (fourcc: FFV1)
235 @item Flash Screen Video @tab X @tab X
237 @item FLIC video @tab @tab X
238 @item FLV @tab X @tab X
239 @tab Sorenson H.263 used in Flash
240 @item Fraps FPS1 @tab @tab X
241 @item H.261 @tab X @tab X
242 @item H.263(+) @tab X @tab X
243 @tab also known as RealVideo 1.0
244 @item H.264 @tab @tab X
245 @item HuffYUV @tab X @tab X
246 @item IBM Ultimotion @tab @tab X
248 @item id Cinematic video @tab @tab X
249 @tab Used in Quake II.
250 @item id RoQ @tab X @tab X
251 @tab Used in Quake III, Jedi Knight 2, other computer games.
252 @item Intel Indeo 3 @tab @tab X
253 @item Interplay Video @tab @tab X
254 @tab Used in Interplay .MVE files.
255 @item JPEG-LS @tab X @tab X
256 @tab fourcc: MJLS, lossless and near-lossless is supported.
257 @item KMVC @tab @tab X
258 @tab Codec used in Worms games.
259 @item LOCO @tab @tab X
260 @item lossless MJPEG @tab X @tab X
261 @item Microsoft RLE @tab @tab X
262 @item Microsoft Video-1 @tab @tab X
263 @item Mimic @tab @tab X
264 @tab Used in MSN Messenger Webcam streams.
265 @item Miro VideoXL @tab @tab X
267 @item MJPEG @tab X @tab X
268 @item Motion Pixels Video @tab @tab X
269 @item MPEG-1 @tab X @tab X
270 @item MPEG-2 @tab X @tab X
271 @item MPEG-4 @tab X @tab X
272 @item MSMPEG4 V1 @tab X @tab X
273 @item MSMPEG4 V2 @tab X @tab X
274 @item MSMPEG4 V3 @tab X @tab X
275 @item MSZH @tab @tab X
277 @item On2 VP3 @tab @tab X
278 @tab still experimental
279 @item On2 VP5 @tab @tab X
281 @item On2 VP6 @tab @tab X
282 @tab fourcc: VP60,VP61,VP62
283 @item planar RGB @tab @tab X
285 @item QPEG @tab @tab X
286 @tab fourccs: QPEG, Q1.0, Q1.1
287 @item RealVideo 1.0 @tab X @tab X
288 @item RealVideo 2.0 @tab X @tab X
289 @item Renderware TXD @tab @tab X
290 @tab Texture dictionaries used by the Renderware Engine.
291 @item RTjpeg @tab @tab X
292 @tab Video encoding used in NuppelVideo files.
293 @item Smacker video @tab @tab X
294 @tab Video encoding used in Smacker.
295 @item Snow @tab X @tab X
296 @tab experimental wavelet codec (fourcc: SNOW)
297 @item Sony PlayStation MDEC @tab @tab X
298 @item Sorenson Video 1 @tab X @tab X
300 @item Sorenson Video 3 @tab @tab X
302 @item Sunplus MJPEG @tab @tab X
304 @item TechSmith Camtasia @tab @tab X
306 @item Theora @tab X @tab X
307 @tab still experimental
308 @item THP @tab @tab X
309 @tab Used on the Nintendo GameCube.
310 @item Tiertex Seq video @tab @tab X
311 @tab Codec used in DOS CD-ROM FlashBack game.
312 @item VC-1 @tab @tab X
313 @item VMD Video @tab @tab X
314 @tab Used in Sierra VMD files.
315 @item VMware Video @tab @tab X
316 @tab Codec used in videos captured by VMware.
317 @item Westwood VQA @tab @tab X
318 @item Winnov WNV1 @tab @tab X
319 @item WMV7 @tab X @tab X
320 @item WMV8 @tab X @tab X
321 @item WMV9 @tab @tab X
322 @tab not completely working
323 @item Xan/WC3 @tab @tab X
324 @tab Used in Wing Commander III .MVE files.
325 @item ZLIB @tab X @tab X
326 @tab part of LCL, encoder experimental
327 @item ZMBV @tab X @tab X
328 @tab Encoder works only in PAL8.
331 @code{X} means that encoding (resp. decoding) is supported.
333 @section Audio Codecs
335 @multitable @columnfractions .4 .1 .1 .1 .7
336 @item Name @tab Encoding @tab Decoding @tab Comments
337 @item 4X IMA ADPCM @tab @tab X
338 @item 8SVX audio @tab @tab X
339 @item AAC @tab X @tab X
340 @tab Encoding is supported through the external library libfaac.
341 @item AC-3 @tab IX @tab IX
342 @item AMR-NB @tab X @tab X
343 @tab Supported through an external library.
344 @item AMR-WB @tab X @tab X
345 @tab Supported through an external library.
346 @item AMV IMA ADPCM @tab @tab X
347 @tab Used in AMV files
348 @item Apple lossless audio @tab X @tab X
349 @tab QuickTime fourcc 'alac'
350 @item Apple MACE 3 @tab @tab X
351 @item Apple MACE 6 @tab @tab X
352 @item ATRAC 3 @tab @tab X
353 @item CD-ROM XA ADPCM @tab @tab X
354 @item Cin audio @tab @tab X
355 @tab Codec used in Delphine Software International games.
356 @item Creative ADPCM @tab @tab X
357 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
358 @item CRI ADX ADPCM @tab X @tab X
359 @tab Used in Sega Dreamcast games.
360 @item DSP Group TrueSpeech @tab @tab X
361 @item DTS Coherent Audio @tab @tab X
362 @item Duck DK3 IMA ADPCM @tab @tab X
363 @tab Used in some Sega Saturn console games.
364 @item Duck DK4 IMA ADPCM @tab @tab X
365 @tab Used in some Sega Saturn console games.
366 @item DV audio @tab @tab X
367 @item Electronic Arts ADPCM @tab @tab X
368 @tab Used in various EA titles.
369 @item Enhanced AC-3 @tab @tab X
370 @item FLAC lossless audio @tab IX @tab X
371 @item G.726 ADPCM @tab X @tab X
372 @item id RoQ DPCM @tab X @tab X
373 @tab Used in Quake III, Jedi Knight 2, other computer games.
374 @item Intel Music Coder @tab @tab X
375 @item Interplay MVE DPCM @tab @tab X
376 @tab Used in various Interplay computer games.
377 @item MAXIS EA ADPCM @tab @tab X
378 @tab Used in Sim City 3000.
379 @item Microsoft ADPCM @tab X @tab X
380 @item MLP/TrueHD @tab @tab X
381 @tab Used in DVD-Audio and Blu-Ray discs.
382 @item Monkey's Audio @tab @tab X
383 @tab Only versions 3.97-3.99 are supported.
384 @item MPEG audio layer 1/3 @tab X @tab IX
385 @tab MP3 encoding is supported through the external library LAME.
386 @item MPEG audio layer 2 @tab IX @tab IX
387 @item MS IMA ADPCM @tab X @tab X
388 @item Musepack @tab @tab X
389 @tab SV7 and SV8 are supported.
390 @item Nellymoser ASAO @tab X @tab X
391 @item Qdesign QDM2 @tab @tab X
392 @tab There are still some distortions.
393 @item QT IMA ADPCM @tab X @tab X
394 @item RA144 @tab @tab X
395 @tab Real 14400 bit/s codec
396 @item RA288 @tab @tab X
397 @tab Real 28800 bit/s codec
398 @item RADnet @tab IX @tab IX
399 @tab Real low bitrate AC-3 codec
400 @item Real COOK @tab @tab X
401 @tab All versions except 5.1 are supported.
402 @item Shorten @tab @tab X
403 @item Sierra Online DPCM @tab @tab X
404 @tab Used in Sierra Online game audio files.
405 @item Smacker audio @tab @tab X
406 @item SMJPEG IMA ADPCM @tab @tab X
407 @tab Used in certain Loki game ports.
408 @item Sonic @tab X @tab X
409 @tab experimental codec
410 @item Sonic lossless @tab X @tab X
411 @tab experimental codec
412 @item THP ADPCM @tab @tab X
413 @tab Used on the Nintendo GameCube.
414 @item True Audio (TTA) @tab @tab X
415 @item Vorbis @tab X @tab X
416 @item WavPack @tab @tab X
417 @item Westwood Studios IMA ADPCM @tab @tab X
418 @tab Used in Westwood Studios games like Command and Conquer.
419 @item WMA v1/v2 @tab X @tab X
420 @item Xan DPCM @tab @tab X
421 @tab Used in Origin's Wing Commander IV AVI files.
424 @code{X} means that encoding (resp. decoding) is supported.
426 @code{I} means that an integer-only version is available, too (ensures high
427 performance on systems without hardware floating point support).
429 @chapter Platform Specific information
433 BSD make will not build FFmpeg, you need to install and use GNU Make
438 To get help and instructions for building FFmpeg under Windows, check out
439 the FFmpeg Windows Help Forum at
440 @url{http://ffmpeg.arrozcru.org/}.
442 @subsection Native Windows compilation
444 FFmpeg can be built to run natively on Windows using the MinGW tools. Install
445 the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
446 You can find detailed installation
447 instructions in the download section and the FAQ.
449 FFmpeg does not build out-of-the-box with the packages the automated MinGW
450 installer provides. It also requires coreutils to be installed and many other
451 packages updated to the latest version. The minimum version for some packages
456 @item msys-make 3.81-2 (note: not mingw32-make)
458 @item mingw-runtime 3.15
461 Within the MSYS shell, configure and make with:
464 ./configure --enable-memalign-hack
469 This will install @file{ffmpeg.exe} along with many other development files
470 to @file{/usr/local}. You may specify another install path using the
471 @code{--prefix} option in @file{configure}.
477 @item In order to compile vhooks, you must have a POSIX-compliant libdl in
478 your MinGW system. Get dlfcn-win32 from
479 @url{http://code.google.com/p/dlfcn-win32}.
481 @item In order to compile FFplay, you must have the MinGW development library
482 of SDL. Get it from @url{http://www.libsdl.org}.
483 Edit the @file{bin/sdl-config} script so that it points to the correct prefix
484 where SDL was installed. Verify that @file{sdl-config} can be launched from
485 the MSYS command line.
487 @item By using @code{./configure --enable-shared} when configuring FFmpeg,
488 you can build libavutil, libavcodec and libavformat as DLLs.
492 @subsection Microsoft Visual C++ compatibility
494 As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
495 want to use the libav* libraries in your own applications, you can still
496 compile those applications using MSVC++. But the libav* libraries you link
497 to @emph{must} be built with MinGW. However, you will not be able to debug
498 inside the libav* libraries, since MSVC++ does not recognize the debug
499 symbols generated by GCC.
500 We strongly recommend you to move over from MSVC++ to MinGW tools.
502 This description of how to use the FFmpeg libraries with MSVC++ is based on
503 Microsoft Visual C++ 2005 Express Edition. If you have a different version,
504 you might have to modify the procedures slightly.
506 @subsubsection Using static libraries
508 Assuming you have just built and installed FFmpeg in @file{/usr/local}.
512 @item Create a new console application ("File / New / Project") and then
513 select "Win32 Console Application". On the appropriate page of the
514 Application Wizard, uncheck the "Precompiled headers" option.
516 @item Write the source code for your application, or, for testing, just
517 copy the code from an existing sample application into the source file
518 that MSVC++ has already created for you. For example, you can copy
519 @file{output_example.c} from the FFmpeg distribution.
521 @item Open the "Project / Properties" dialog box. In the "Configuration"
522 combo box, select "All Configurations" so that the changes you make will
523 affect both debug and release builds. In the tree view on the left hand
524 side, select "C/C++ / General", then edit the "Additional Include
525 Directories" setting to contain the path where the FFmpeg includes were
526 installed (i.e. @file{c:\msys\1.0\local\include}).
527 Do not add MinGW's include directory here, or the include files will
528 conflict with MSVC's.
530 @item Still in the "Project / Properties" dialog box, select
531 "Linker / General" from the tree view and edit the
532 "Additional Library Directories" setting to contain the @file{lib}
533 directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
534 the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
535 and the directory where MinGW's GCC libs are installed
536 (i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
537 "Linker / Input" from the tree view, and add the files @file{libavformat.a},
538 @file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
539 @file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
540 to the end of "Additional Dependencies".
542 @item Now, select "C/C++ / Code Generation" from the tree view. Select
543 "Debug" in the "Configuration" combo box. Make sure that "Runtime
544 Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
545 the "Configuration" combo box and make sure that "Runtime Library" is
546 set to "Multi-threaded DLL".
548 @item Click "OK" to close the "Project / Properties" dialog box.
550 @item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
551 Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
552 and install it in MSVC++'s include directory
553 (i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
555 @item MSVC++ also does not understand the @code{inline} keyword used by
556 FFmpeg, so you must add this line before @code{#include}ing libav*:
558 #define inline _inline
561 @item Build your application, everything should work.
565 @subsubsection Using shared libraries
567 This is how to create DLL and LIB files that are compatible with MSVC++:
571 @item Add a call to @file{vcvars32.bat} (which sets up the environment
572 variables for the Visual C++ tools) as the first line of @file{msys.bat}.
573 The standard location for @file{vcvars32.bat} is
574 @file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
575 and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
576 If this corresponds to your setup, add the following line as the first line
580 call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
583 Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
584 and run @file{c:\msys\1.0\msys.bat} from there.
586 @item Within the MSYS shell, run @code{lib.exe}. If you get a help message
587 from @file{Microsoft (R) Library Manager}, this means your environment
588 variables are set up correctly, the @file{Microsoft (R) Library Manager}
589 is on the path and will be used by FFmpeg to create
590 MSVC++-compatible import libraries.
592 @item Build FFmpeg with
595 ./configure --enable-shared --enable-memalign-hack
600 Your install path (@file{/usr/local/} by default) should now have the
601 necessary DLL and LIB files under the @file{bin} directory.
605 To use those files with MSVC++, do the same as you would do with
606 the static libraries, as described above. But in Step 4,
607 you should only need to add the directory where the LIB files are installed
608 (i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
609 installed in the @file{bin} directory. And instead of adding @file{libxx.a}
610 files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
611 @file{avutil.lib}. There should be no need for @file{libmingwex.a},
612 @file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
613 statically linked into the DLLs. The @file{bin} directory contains a bunch
614 of DLL files, but the ones that are actually used to run your application
615 are the ones with a major version number in their filenames
616 (i.e. @file{avcodec-51.dll}).
618 @subsection Cross compilation for Windows with Linux
620 You must use the MinGW cross compilation tools available at
621 @url{http://www.mingw.org/}.
623 Then configure FFmpeg with the following options:
625 ./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
627 (you can change the cross-prefix according to the prefix chosen for the
630 Then you can easily test FFmpeg with Wine
631 (@url{http://www.winehq.com/}).
633 @subsection Compilation under Cygwin
635 The main issue with Cygwin is that newlib, its C library, does not
636 contain llrint(). However, it is possible to leverage the
637 implementation in MinGW.
639 Just install your Cygwin with all the "Base" packages, plus the
640 following "Devel" ones:
642 binutils, gcc-core, make, subversion, mingw-runtime
645 Do not install binutils-20060709-1 (they are buggy on shared builds);
646 use binutils-20050610-1 instead.
648 Then create a small library that just contains llrint():
651 ar x /usr/lib/mingw/libmingwex.a llrint.o
652 ar cq /usr/local/lib/libllrint.a llrint.o
658 ./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
661 to make a static build or
664 ./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
667 to build shared libraries.
669 If you want to build FFmpeg with additional libraries, download Cygwin
670 "Devel" packages for Ogg and Vorbis from any Cygwin packages repository
671 and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
672 (@url{http://cygwinports.dotsrc.org/}).
674 @subsection Crosscompilation for Windows under Cygwin
676 With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
678 Just install your Cygwin as explained before, plus these additional
681 gcc-mingw-core, mingw-runtime, mingw-zlib
684 and add some special flags to your configure invocation.
686 For a static build run
688 ./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
691 and for a build with shared libraries
693 ./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
698 BeOS support is broken in mysterious ways.
702 For information about compiling FFmpeg on OS/2 see
703 @url{http://www.edm2.com/index.php/FFmpeg}.
705 @chapter Developers Guide
709 @item libavcodec is the library containing the codecs (both encoding and
710 decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
712 @item libavformat is the library containing the file format handling (mux and
713 demux code for several formats). Look at @file{ffplay.c} to use it in a
714 player. See @file{output_example.c} to use it to generate audio or video
719 @section Integrating libavcodec or libavformat in your program
721 You can integrate all the source code of the libraries to link them
722 statically to avoid any version problem. All you need is to provide a
723 'config.mak' and a 'config.h' in the parent directory. See the defines
724 generated by ./configure to understand what is needed.
726 You can use libavcodec or libavformat in your commercial program, but
727 @emph{any patch you make must be published}. The best way to proceed is
728 to send your patches to the FFmpeg mailing list.
731 @section Coding Rules
733 FFmpeg is programmed in the ISO C90 language with a few additional
734 features from ISO C99, namely:
737 the @samp{inline} keyword;
741 designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
743 compound literals (@samp{x = (struct s) @{ 17, 23 @};})
746 These features are supported by all compilers we care about, so we will not
747 accept patches to remove their use unless they absolutely do not impair
748 clarity and performance.
750 All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
751 compiles with several other compilers, such as the Compaq ccc compiler
752 or Sun Studio 9, and we would like to keep it that way unless it would
753 be exceedingly involved. To ensure compatibility, please do not use any
754 additional C99 features or GCC extensions. Especially watch out for:
757 mixing statements and declarations;
759 @samp{long long} (use @samp{int64_t} instead);
761 @samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
763 GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
767 The presentation is the one specified by 'indent -i4 -kr -nut'.
768 The TAB character is forbidden outside of Makefiles as is any
769 form of trailing whitespace. Commits containing either will be
770 rejected by the Subversion repository.
772 The main priority in FFmpeg is simplicity and small code size in order to
773 minimize the bug count.
775 Comments: Use the JavaDoc/Doxygen
776 format (see examples below) so that code documentation
777 can be generated automatically. All nontrivial functions should have a comment
778 above them explaining what the function does, even if it is just one sentence.
779 All structures and their member variables should be documented, too.
792 typedef struct Foobar@{
793 int var1; /**< var1 description */
794 int var2; ///< var2 description
795 /** var3 description */
803 * @@param my_parameter description of my_parameter
804 * @@return return value description
806 int myfunc(int my_parameter)
810 fprintf and printf are forbidden in libavformat and libavcodec,
811 please use av_log() instead.
813 Casts should be used only when necessary. Unneeded parentheses
814 should also be avoided if they don't make the code easier to understand.
816 @section Development Policy
820 Contributions should be licensed under the LGPL 2.1, including an
821 "or any later version" clause, or the MIT license. GPL 2 including
822 an "or any later version" clause is also acceptable, but LGPL is
825 You must not commit code which breaks FFmpeg! (Meaning unfinished but
826 enabled code which breaks compilation or compiles but does not work or
827 breaks the regression tests)
828 You can commit unfinished stuff (for testing etc), but it must be disabled
829 (#ifdef etc) by default so it does not interfere with other developers'
832 You do not have to over-test things. If it works for you, and you think it
833 should work for others, then commit. If your code has problems
834 (portability, triggers compiler bugs, unusual environment etc) they will be
835 reported and eventually fixed.
837 Do not commit unrelated changes together, split them into self-contained
838 pieces. Also do not forget that if part B depends on part A, but A does not
839 depend on B, then A can and should be committed first and separate from B.
840 Keeping changes well split into self-contained parts makes reviewing and
841 understanding them on the commit log mailing list easier. This also helps
842 in case of debugging later on.
843 Also if you have doubts about splitting or not splitting, do not hesitate to
844 ask/discuss it on the developer mailing list.
846 Do not change behavior of the program (renaming options etc) without
847 first discussing it on the ffmpeg-devel mailing list. Do not remove
848 functionality from the code. Just improve!
850 Note: Redundant code can be removed.
852 Do not commit changes to the build system (Makefiles, configure script)
853 which change behavior, defaults etc, without asking first. The same
854 applies to compiler warning fixes, trivial looking fixes and to code
855 maintained by other developers. We usually have a reason for doing things
856 the way we do. Send your changes as patches to the ffmpeg-devel mailing
857 list, and if the code maintainers say OK, you may commit. This does not
858 apply to files you wrote and/or maintain.
860 We refuse source indentation and other cosmetic changes if they are mixed
861 with functional changes, such commits will be rejected and removed. Every
862 developer has his own indentation style, you should not change it. Of course
863 if you (re)write something, you can use your own style, even though we would
864 prefer if the indentation throughout FFmpeg was consistent (Many projects
865 force a given indentation style - we do not.). If you really need to make
866 indentation changes (try to avoid this), separate them strictly from real
869 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
870 then either do NOT change the indentation of the inner part within (do not
871 move it to the right)! or do so in a separate commit
873 Always fill out the commit log message. Describe in a few lines what you
874 changed and why. You can refer to mailing list postings if you fix a
875 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
877 If you apply a patch by someone else, include the name and email address in
878 the log message. Since the ffmpeg-cvslog mailing list is publicly
879 archived you should add some SPAM protection to the email address. Send an
880 answer to ffmpeg-devel (or wherever you got the patch from) saying that
881 you applied the patch.
883 When applying patches that have been discussed (at length) on the mailing
884 list, reference the thread in the log message.
886 Do NOT commit to code actively maintained by others without permission.
887 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
888 timeframe (12h for build failures and security fixes, 3 days small changes,
889 1 week for big patches) then commit your patch if you think it is OK.
890 Also note, the maintainer can simply ask for more time to review!
892 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
893 are sent there and reviewed by all the other developers. Bugs and possible
894 improvements or general questions regarding commits are discussed there. We
895 expect you to react if problems with your code are uncovered.
897 Update the documentation if you change behavior or add features. If you are
898 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
899 maintainer(s) will review and commit your stuff.
901 Try to keep important discussions and requests (also) on the public
902 developer mailing list, so that all developers can benefit from them.
904 Never write to unallocated memory, never write over the end of arrays,
905 always check values read from some untrusted source before using them
906 as array index or other risky things.
908 Remember to check if you need to bump versions for the specific libav
909 parts (libavutil, libavcodec, libavformat) you are changing. You need
910 to change the version integer.
911 Incrementing the first component means no backward compatibility to
912 previous versions (e.g. removal of a function from the public API).
913 Incrementing the second component means backward compatible change
914 (e.g. addition of a function to the public API or extension of an
915 existing data structure).
916 Incrementing the third component means a noteworthy binary compatible
917 change (e.g. encoder bug fix that matters for the decoder).
919 Compiler warnings indicate potential bugs or code with bad style. If a type of
920 warning always points to correct and clean code, that warning should
921 be disabled, not the code changed.
922 Thus the remaining warnings can either be bugs or correct code.
923 If it is a bug, the bug has to be fixed. If it is not, the code should
924 be changed to not generate a warning unless that causes a slowdown
925 or obfuscates the code.
927 If you add a new file, give it a proper license header. Do not copy and
928 paste it from a random place, use an existing file as template.
931 We think our rules are not too hard. If you have comments, contact us.
933 Note, these rules are mostly borrowed from the MPlayer project.
935 @section Submitting patches
937 First, (@pxref{Coding Rules}) above if you did not yet.
939 When you submit your patch, try to send a unified diff (diff '-up'
940 option). We cannot read other diffs :-)
942 Also please do not submit a patch which contains several unrelated changes.
943 Split it into separate, self-contained pieces. This does not mean splitting
944 file by file. Instead, make the patch as small as possible while still
945 keeping it as a logical unit that contains an individual change, even
946 if it spans multiple files. This makes reviewing your patches much easier
947 for us and greatly increases your chances of getting your patch applied.
949 Run the regression tests before submitting a patch so that you can
950 verify that there are no big problems.
952 Patches should be posted as base64 encoded attachments (or any other
953 encoding which ensures that the patch will not be trashed during
954 transmission) to the ffmpeg-devel mailing list, see
955 @url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
957 It also helps quite a bit if you tell us what the patch does (for example
958 'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
961 Also please if you send several patches, send each patch as a separate mail,
962 do not attach several unrelated patches to the same mail.
964 @section New codecs or formats checklist
968 Did you use av_cold for codec initialization and close functions?
970 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
971 AVInputFormat/AVOutputFormat struct?
973 Did you bump the minor version number in @file{avcodec.h} or
976 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
978 Did you add the CodecID to @file{avcodec.h}?
980 If it has a fourcc, did you add it to @file{libavformat/riff.c},
981 even if it is only a decoder?
983 Did you add a rule to compile the appropriate files in the Makefile?
984 Remember to do this even if you're just adding a format to a file that is
985 already being compiled by some other rule, like a raw demuxer.
987 Did you add an entry to the table of supported formats or codecs in the
990 Did you add an entry in the Changelog?
992 If it depends on a parser or a library, did you add that dependency in
995 Did you "svn add" the appropriate files before commiting?
998 @section patch submission checklist
1002 Do the regression tests pass with the patch applied?
1004 Is the patch a unified diff?
1006 Is the patch against latest FFmpeg SVN?
1008 Are you subscribed to ffmpeg-dev?
1009 (the list is subscribers only due to spam)
1011 Have you checked that the changes are minimal, so that the same cannot be
1012 achieved with a smaller patch and/or simpler final code?
1014 If the change is to speed critical code, did you benchmark it?
1016 If you did any benchmarks, did you provide them in the mail?
1018 Have you checked that the patch does not introduce buffer overflows or
1019 other security issues?
1021 If you add a new demuxer or decoder, have you checked that it does not
1022 crash with damaged input (see tools/trasher)?
1024 Is the patch created from the root of the source tree, so it can be
1025 applied with @code{patch -p0}?
1027 Does the patch not mix functional and cosmetic changes?
1029 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1031 Is the patch attached to the email you send?
1033 Is the mime type of the patch correct? It should be text/x-diff or
1034 text/x-patch or at least text/plain and not application/octet-stream.
1036 If the patch fixes a bug, did you provide a verbose analysis of the bug?
1038 If the patch fixes a bug, did you provide enough information, including
1039 a sample, so the bug can be reproduced and the fix can be verified?
1040 Note please do not attach samples >100k to mails but rather provide a
1041 URL, you can upload to ftp://upload.mplayerhq.hu
1043 Did you provide a verbose summary about what the patch does change?
1045 Did you provide a verbose explanation why it changes things like it does?
1047 Did you provide a verbose summary of the user visible advantages and
1048 disadvantages if the patch is applied?
1050 Did you provide an example so we can verify the new feature added by the
1053 If you added a new file, did you insert a license header? It should be
1054 taken from FFmpeg, not randomly copied and pasted from somewhere else.
1056 You should maintain alphabetical order in alphabetically ordered lists as
1057 long as doing so does not break API/ABI compatibility.
1059 Lines with similar content should be aligned vertically when doing so
1060 improves readability.
1062 Did you provide a suggestion for a clear commit log message?
1064 Did you test your decoder or demuxer against damaged data? If no, see
1065 tools/trasher and the noise bitstream filter. Your decoder or demuxer
1066 should not crash or end in a (near) infinite loop when fed damaged data.
1069 @section Patch review process
1071 All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1072 clear note that the patch is not for SVN.
1073 Reviews and comments will be posted as replies to the patch on the
1074 mailing list. The patch submitter then has to take care of every comment,
1075 that can be by resubmitting a changed patch or by discussion. Resubmitted
1076 patches will themselves be reviewed like any other patch. If at some point
1077 a patch passes review with no comments then it is approved, that can for
1078 simple and small patches happen immediately while large patches will generally
1079 have to be changed and reviewed many times before they are approved.
1080 After a patch is approved it will be committed to the repository.
1082 We will review all submitted patches, but sometimes we are quite busy so
1083 especially for large patches this can take several weeks.
1085 When resubmitting patches, please do not make any significant changes
1086 not related to the comments received during review. Such patches will
1087 be rejected. Instead, submit significant changes or new features as
1090 @section Regression tests
1092 Before submitting a patch (or committing to the repository), you should at least
1093 test that you did not break anything.
1095 The regression tests build a synthetic video stream and a synthetic
1096 audio stream. These are then encoded and decoded with all codecs or
1097 formats. The CRC (or MD5) of each generated file is recorded in a
1098 result file. A 'diff' is launched to compare the reference results and
1101 The regression tests then go on to test the FFserver code with a
1102 limited set of streams. It is important that this step runs correctly
1105 Run 'make test' to test all the codecs and formats.
1107 Run 'make fulltest' to test all the codecs, formats and FFserver.
1109 [Of course, some patches may change the results of the regression tests. In
1110 this case, the reference results of the regression tests shall be modified