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 Supported File Format @tab Encoding @tab Decoding @tab Comments
44 @item MPEG audio @tab X @tab X
45 @item MPEG-1 systems @tab X @tab X
46 @tab muxed audio and video
47 @item MPEG-2 PS @tab X @tab X
48 @tab also known as @code{VOB} file
49 @item MPEG-2 TS @tab @tab X
50 @tab also known as DVB Transport Stream
51 @item ASF@tab X @tab X
52 @item AVI@tab X @tab X
53 @item WAV@tab X @tab X
54 @item Macromedia Flash@tab X @tab X
55 @item AVM2 (Flash 9) @tab X @tab X
56 @tab Only embedded audio is decoded.
57 @item FLV @tab X @tab X
58 @tab Macromedia Flash video files
59 @item Real Audio and Video @tab X @tab X
60 @item Raw AC3 @tab X @tab X
61 @item Raw MJPEG @tab X @tab X
62 @item Raw MPEG video @tab X @tab X
63 @item Raw PCM8/16 bits, mulaw/Alaw@tab X @tab X
64 @item Raw CRI ADX audio @tab X @tab X
65 @item Raw Shorten audio @tab @tab X
66 @item SUN AU format @tab X @tab X
67 @item NUT @tab X @tab X @tab NUT Open Container Format
68 @item QuickTime @tab X @tab X
69 @item MPEG-4 @tab X @tab X
70 @tab MPEG-4 is a variant of QuickTime.
71 @item Raw MPEG4 video @tab X @tab X
72 @item DV @tab X @tab X
74 @tab 4X Technologies format, used in some games.
75 @item PlayStation STR @tab @tab X
76 @item id RoQ @tab X @tab X
77 @tab Used in Quake III, Jedi Knight 2, other computer games.
78 @item Interplay MVE @tab @tab X
79 @tab Format used in various Interplay computer games.
80 @item WC3 Movie @tab @tab X
81 @tab Multimedia format used in Origin's Wing Commander III computer game.
82 @item Sega FILM/CPK @tab @tab X
83 @tab Used in many Sega Saturn console games.
84 @item Westwood Studios VQA/AUD @tab @tab X
85 @tab Multimedia formats used in Westwood Studios games.
86 @item id Cinematic (.cin) @tab @tab X
87 @tab Used in Quake II.
88 @item FLIC format @tab @tab X
90 @item Sierra VMD @tab @tab X
91 @tab Used in Sierra CD-ROM games.
92 @item Sierra Online @tab @tab X
93 @tab .sol files used in Sierra Online games.
94 @item Matroska @tab X @tab X
95 @item Electronic Arts Multimedia @tab @tab X
96 @tab Used in various EA games; files have extensions like WVE and UV2.
97 @item MAXIS EA XA @tab @tab X
98 @tab Used in Sim City 3000; file extension .xa.
99 @item Nullsoft Video (NSV) format @tab @tab X
100 @item ADTS AAC audio @tab X @tab X
101 @item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro.
102 @item American Laser Games MM @tab @tab X
103 @tab Multimedia format used in games like Mad Dog McCree
104 @item AVS @tab @tab X
105 @tab Multimedia format used by the Creature Shock game.
106 @item Smacker @tab @tab X
107 @tab Multimedia format used by many games.
108 @item GXF @tab X @tab X
109 @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.
110 @item CIN @tab @tab X
111 @tab Multimedia format used by Delphine Software games.
112 @item MXF @tab @tab X
113 @tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
114 @item SEQ @tab @tab X
115 @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
116 @item DXA @tab @tab X
117 @tab This format is used in non-Windows version of Feeble Files game and
118 different game cutscenes repacked for use with ScummVM.
119 @item THP @tab @tab X
120 @tab Used on the Nintendo GameCube.
121 @item C93 @tab @tab X
122 @tab Used in the game Cyberia from Interplay.
123 @item Bethsoft VID @tab @tab X
124 @tab Used in some games from Bethesda Softworks.
125 @item CRYO APC @tab @tab X
126 @tab Audio format used in some games by CRYO Interactive Entertainment.
127 @item Monkey's Audio @tab @tab X
128 @item SIFF @tab @tab X
129 @tab Audio and video format used in some games by Beam Software
130 @item LMLM4 @tab @tab X
131 @tab Used by Linux Media Labs MPEG-4 PCI boards
132 @item PVA @tab @tab X
133 @tab Used by TechnoTrend DVB PCI boards
134 @item MSN TCP Webcam @tab @tab X
135 @tab Used by MSN Messenger Webcam streams.
136 @item RL2 @tab @tab X
137 @tab Audio and video format used in some games by Entertainment Software Partners
138 @item IFF @tab @tab X
139 @tab Interchange File Format
140 @item BFI @tab @tab X
141 @tab Brute Force & Ignorance, used in Flash Traffic: City of Angels
142 @item OMA @tab @tab X
143 @tab Audio format used in Sony Sonic Stage and Sony Vegas
146 @code{X} means that encoding (resp. decoding) is supported.
148 @section Image Formats
150 FFmpeg can read and write images for each frame of a video sequence. The
151 following image formats are supported:
153 @multitable @columnfractions .4 .1 .1 .4
154 @item Supported Image Format @tab Encoding @tab Decoding @tab Comments
155 @item PGM, PPM @tab X @tab X
156 @item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
157 @item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
158 @item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
159 @item .Y.U.V @tab X @tab X @tab one raw file per component
160 @item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
161 @item PNG @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
162 @item Targa @tab @tab X @tab Targa (.TGA) image format.
163 @item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
164 @item SGI @tab X @tab X @tab SGI RGB image format
165 @item PTX @tab @tab X @tab V.Flash PTX format
166 @item RAS @tab @tab X @tab Sun Rasterfile
167 @item PCX @tab @tab X @tab PC Paintbrush
170 @code{X} means that encoding (resp. decoding) is supported.
172 @section Video Codecs
174 @multitable @columnfractions .4 .1 .1 .4
175 @item Supported Codec @tab Encoding @tab Decoding @tab Comments
176 @item MPEG-1 video @tab X @tab X
177 @item MPEG-2 video @tab X @tab X
178 @item MPEG-4 @tab X @tab X
179 @item MSMPEG4 V1 @tab X @tab X
180 @item MSMPEG4 V2 @tab X @tab X
181 @item MSMPEG4 V3 @tab X @tab X
182 @item WMV7 @tab X @tab X
183 @item WMV8 @tab X @tab X @tab not completely working
184 @item WMV9 @tab @tab X @tab not completely working
185 @item VC1 @tab @tab X
186 @item H.261 @tab X @tab X
187 @item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0
188 @item H.264 @tab @tab X
189 @item RealVideo 1.0 @tab X @tab X
190 @item RealVideo 2.0 @tab X @tab X
191 @item MJPEG @tab X @tab X
192 @item lossless MJPEG @tab X @tab X
193 @item JPEG-LS @tab X @tab X @tab fourcc: MJLS, lossless and near-lossless is supported
194 @item Apple MJPEG-B @tab @tab X
195 @item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X
196 @item DV @tab X @tab X
197 @item HuffYUV @tab X @tab X
198 @item FFmpeg Video 1 @tab X @tab X @tab experimental lossless codec (fourcc: FFV1)
199 @item FFmpeg Snow @tab X @tab X @tab experimental wavelet codec (fourcc: SNOW)
200 @item Asus v1 @tab X @tab X @tab fourcc: ASV1
201 @item Asus v2 @tab X @tab X @tab fourcc: ASV2
202 @item Creative YUV @tab @tab X @tab fourcc: CYUV
203 @item Sorenson Video 1 @tab X @tab X @tab fourcc: SVQ1
204 @item Sorenson Video 3 @tab @tab X @tab fourcc: SVQ3
205 @item On2 VP3 @tab @tab X @tab still experimental
206 @item On2 VP5 @tab @tab X @tab fourcc: VP50
207 @item On2 VP6 @tab @tab X @tab fourcc: VP60,VP61,VP62
208 @item Theora @tab X @tab X @tab still experimental
209 @item Intel Indeo 3 @tab @tab X
210 @item FLV @tab X @tab X @tab Sorenson H.263 used in Flash
211 @item Flash Screen Video @tab X @tab X @tab fourcc: FSV1
212 @item ATI VCR1 @tab @tab X @tab fourcc: VCR1
213 @item ATI VCR2 @tab @tab X @tab fourcc: VCR2
214 @item Cirrus Logic AccuPak @tab @tab X @tab fourcc: CLJR
215 @item 4X Video @tab @tab X @tab Used in certain computer games.
216 @item Sony PlayStation MDEC @tab @tab X
217 @item id RoQ @tab X @tab X @tab Used in Quake III, Jedi Knight 2, other computer games.
218 @item Xan/WC3 @tab @tab X @tab Used in Wing Commander III .MVE files.
219 @item Interplay Video @tab @tab X @tab Used in Interplay .MVE files.
220 @item Apple Animation @tab X @tab X @tab fourcc: 'rle '
221 @item Apple Graphics @tab @tab X @tab fourcc: 'smc '
222 @item Apple Video @tab @tab X @tab fourcc: rpza
223 @item Apple QuickDraw @tab @tab X @tab fourcc: qdrw
224 @item Cinepak @tab @tab X
225 @item Microsoft RLE @tab @tab X
226 @item Microsoft Video-1 @tab @tab X
227 @item Westwood VQA @tab @tab X
228 @item id Cinematic Video @tab @tab X @tab Used in Quake II.
229 @item Planar RGB @tab @tab X @tab fourcc: 8BPS
230 @item FLIC video @tab @tab X
231 @item Duck TrueMotion v1 @tab @tab X @tab fourcc: DUCK
232 @item Duck TrueMotion v2 @tab @tab X @tab fourcc: TM20
233 @item VMD Video @tab @tab X @tab Used in Sierra VMD files.
234 @item MSZH @tab @tab X @tab Part of LCL
235 @item ZLIB @tab X @tab X @tab Part of LCL, encoder experimental
236 @item TechSmith Camtasia @tab @tab X @tab fourcc: TSCC
237 @item IBM Ultimotion @tab @tab X @tab fourcc: ULTI
238 @item Miro VideoXL @tab @tab X @tab fourcc: VIXL
239 @item QPEG @tab @tab X @tab fourccs: QPEG, Q1.0, Q1.1
240 @item LOCO @tab @tab X @tab
241 @item Winnov WNV1 @tab @tab X @tab
242 @item Autodesk Animator Studio Codec @tab @tab X @tab fourcc: AASC
243 @item Fraps FPS1 @tab @tab X @tab
244 @item CamStudio @tab @tab X @tab fourcc: CSCD
245 @item American Laser Games Video @tab @tab X @tab Used in games like Mad Dog McCree
246 @item ZMBV @tab X @tab X @tab Encoder works only on PAL8
247 @item AVS Video @tab @tab X @tab Video encoding used by the Creature Shock game.
248 @item Smacker Video @tab @tab X @tab Video encoding used in Smacker.
249 @item RTjpeg @tab @tab X @tab Video encoding used in NuppelVideo files.
250 @item KMVC @tab @tab X @tab Codec used in Worms games.
251 @item VMware Video @tab @tab X @tab Codec used in videos captured by VMware.
252 @item Cin Video @tab @tab X @tab Codec used in Delphine Software games.
253 @item Tiertex Seq Video @tab @tab X @tab Codec used in DOS CD-ROM FlashBack game.
254 @item DXA Video @tab @tab X @tab Codec originally used in Feeble Files game.
255 @item AVID DNxHD @tab X @tab X @tab aka SMPTE VC3
256 @item C93 Video @tab @tab X @tab Codec used in Cyberia game.
257 @item THP @tab @tab X @tab Used on the Nintendo GameCube.
258 @item Bethsoft VID @tab @tab X @tab Used in some games from Bethesda Softworks.
259 @item Renderware TXD @tab @tab X @tab Texture dictionaries used by the Renderware Engine.
260 @item AMV @tab @tab X @tab Used in Chinese MP3 players.
261 @item Mimic @tab @tab X @tab Used in MSN Messenger Webcam streams.
264 @code{X} means that encoding (resp. decoding) is supported.
266 @section Audio Codecs
268 @multitable @columnfractions .4 .1 .1 .1 .7
269 @item Supported Codec @tab Encoding @tab Decoding @tab Comments
270 @item MPEG audio layer 2 @tab IX @tab IX
271 @item MPEG audio layer 1/3 @tab X @tab IX
272 @tab MP3 encoding is supported through the external library LAME.
273 @item AC3 @tab IX @tab IX
274 @tab liba52 is used internally for decoding.
275 @item Vorbis @tab X @tab X
276 @item WMA V1/V2 @tab X @tab X
277 @item AAC @tab X @tab X
278 @tab Supported through the external library libfaac/libfaad.
279 @item Microsoft ADPCM @tab X @tab X
280 @item AMV IMA ADPCM @tab @tab X
281 @tab Used in AMV files
282 @item MS IMA ADPCM @tab X @tab X
283 @item QT IMA ADPCM @tab X @tab X
284 @item 4X IMA ADPCM @tab @tab X
285 @item G.726 ADPCM @tab X @tab X
286 @item Duck DK3 IMA ADPCM @tab @tab X
287 @tab Used in some Sega Saturn console games.
288 @item Duck DK4 IMA ADPCM @tab @tab X
289 @tab Used in some Sega Saturn console games.
290 @item Westwood Studios IMA ADPCM @tab @tab X
291 @tab Used in Westwood Studios games like Command and Conquer.
292 @item SMJPEG IMA ADPCM @tab @tab X
293 @tab Used in certain Loki game ports.
294 @item CD-ROM XA ADPCM @tab @tab X
295 @item CRI ADX ADPCM @tab X @tab X
296 @tab Used in Sega Dreamcast games.
297 @item Electronic Arts ADPCM @tab @tab X
298 @tab Used in various EA titles.
299 @item MAXIS EA ADPCM @tab @tab X
300 @tab Used in Sim City 3000.
301 @item Creative ADPCM @tab @tab X
302 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
303 @item THP ADPCM @tab @tab X
304 @tab Used on the Nintendo GameCube.
305 @item RA144 @tab @tab X
306 @tab Real 14400 bit/s codec
307 @item RA288 @tab @tab X
308 @tab Real 28800 bit/s codec
309 @item RADnet @tab X @tab IX
310 @tab Real low bitrate AC3 codec, liba52 is used for decoding.
311 @item AMR-NB @tab X @tab X
312 @tab Supported through an external library.
313 @item AMR-WB @tab X @tab X
314 @tab Supported through an external library.
315 @item DV audio @tab @tab X
316 @item id RoQ DPCM @tab X @tab X
317 @tab Used in Quake III, Jedi Knight 2, other computer games.
318 @item Interplay MVE DPCM @tab @tab X
319 @tab Used in various Interplay computer games.
320 @item Xan DPCM @tab @tab X
321 @tab Used in Origin's Wing Commander IV AVI files.
322 @item Sierra Online DPCM @tab @tab X
323 @tab Used in Sierra Online game audio files.
324 @item Apple MACE 3 @tab @tab X
325 @item Apple MACE 6 @tab @tab X
326 @item FLAC lossless audio @tab X @tab X
327 @item Shorten lossless audio @tab @tab X
328 @item Apple lossless audio @tab @tab X
329 @tab QuickTime fourcc 'alac'
330 @item FFmpeg Sonic @tab X @tab X
331 @tab experimental lossy/lossless codec
332 @item Qdesign QDM2 @tab @tab X
333 @tab there are still some distortions
334 @item Real COOK @tab @tab X
335 @tab All versions except 5.1 are supported
336 @item DSP Group TrueSpeech @tab @tab X
337 @item True Audio (TTA) @tab @tab X
338 @item Smacker Audio @tab @tab X
339 @item WavPack Audio @tab @tab X
340 @item Cin Audio @tab @tab X
341 @tab Codec used in Delphine Software games.
342 @item Intel Music Coder @tab @tab X
343 @item Musepack @tab @tab X
344 @tab SV7 and SV8 are supported
345 @item DTS Coherent Audio @tab @tab X
346 @item ATRAC 3 @tab @tab X
347 @item Monkey's Audio @tab @tab X @tab Only versions 3.97-3.99 are supported
348 @item Nellymoser ASAO @tab @tab X
349 @item 8SVX Audio @tab @tab X
350 @item MLP/TrueHD @tab @tab X @tab Used in DVD-Audio and Blu-Ray discs.
353 @code{X} means that encoding (resp. decoding) is supported.
355 @code{I} means that an integer-only version is available, too (ensures high
356 performance on systems without hardware floating point support).
358 @chapter Platform Specific information
362 BSD make will not build FFmpeg, you need to install and use GNU Make
367 To get help and instructions for building FFmpeg under Windows, check out
368 the FFmpeg Windows Help Forum at
369 @url{http://arrozcru.no-ip.org/ffmpeg/}.
371 @subsection Native Windows compilation
373 FFmpeg can be built to run natively on Windows using the MinGW tools. Install
374 the current versions of MSYS and MinGW from @url{http://www.mingw.org/}. Also
375 install the coreutils package, and update to the latest MSYS make (note: not
376 mingw32-make). You can find detailed installation
377 instructions in the download section and the FAQ.
379 Within the MSYS shell, configure and make with:
382 ./configure --enable-memalign-hack
387 This will install @file{ffmpeg.exe} along with many other development files
388 to @file{/usr/local}. You may specify another install path using the
389 @code{--prefix} option in @file{configure}.
395 @item Use at least bash 3.1. Older versions are known to fail on the
398 @item In order to compile vhooks, you must have a POSIX-compliant libdl in
399 your MinGW system. Get dlfcn-win32 from
400 @url{http://code.google.com/p/dlfcn-win32}.
402 @item In order to compile FFplay, you must have the MinGW development library
403 of SDL. Get it from @url{http://www.libsdl.org}.
404 Edit the @file{bin/sdl-config} script so that it points to the correct prefix
405 where SDL was installed. Verify that @file{sdl-config} can be launched from
406 the MSYS command line.
408 @item By using @code{./configure --enable-shared} when configuring FFmpeg,
409 you can build libavutil, libavcodec and libavformat as DLLs.
413 @subsection Microsoft Visual C++ compatibility
415 As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
416 want to use the libav* libraries in your own applications, you can still
417 compile those applications using MSVC++. But the libav* libraries you link
418 to @emph{must} be built with MinGW. However, you will not be able to debug
419 inside the libav* libraries, since MSVC++ does not recognize the debug
420 symbols generated by GCC.
421 We strongly recommend you to move over from MSVC++ to MinGW tools.
423 This description of how to use the FFmpeg libraries with MSVC++ is based on
424 Microsoft Visual C++ 2005 Express Edition. If you have a different version,
425 you might have to modify the procedures slightly.
427 @subsubsection Using static libraries
429 Assuming you have just built and installed FFmpeg in @file{/usr/local}.
433 @item Create a new console application ("File / New / Project") and then
434 select "Win32 Console Application". On the appropriate page of the
435 Application Wizard, uncheck the "Precompiled headers" option.
437 @item Write the source code for your application, or, for testing, just
438 copy the code from an existing sample application into the source file
439 that MSVC++ has already created for you. For example, you can copy
440 @file{output_example.c} from the FFmpeg distribution.
442 @item Open the "Project / Properties" dialog box. In the "Configuration"
443 combo box, select "All Configurations" so that the changes you make will
444 affect both debug and release builds. In the tree view on the left hand
445 side, select "C/C++ / General", then edit the "Additional Include
446 Directories" setting to contain the path where the FFmpeg includes were
447 installed (i.e. @file{c:\msys\1.0\local\include}).
448 Do not add MinGW's include directory here, or the include files will
449 conflict with MSVC's.
451 @item Still in the "Project / Properties" dialog box, select
452 "Linker / General" from the tree view and edit the
453 "Additional Library Directories" setting to contain the @file{lib}
454 directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
455 the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
456 and the directory where MinGW's GCC libs are installed
457 (i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
458 "Linker / Input" from the tree view, and add the files @file{libavformat.a},
459 @file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
460 @file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
461 to the end of "Additional Dependencies".
463 @item Now, select "C/C++ / Code Generation" from the tree view. Select
464 "Debug" in the "Configuration" combo box. Make sure that "Runtime
465 Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
466 the "Configuration" combo box and make sure that "Runtime Library" is
467 set to "Multi-threaded DLL".
469 @item Click "OK" to close the "Project / Properties" dialog box.
471 @item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
472 Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
473 and install it in MSVC++'s include directory
474 (i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
476 @item MSVC++ also does not understand the @code{inline} keyword used by
477 FFmpeg, so you must add this line before @code{#include}ing libav*:
479 #define inline _inline
482 @item Build your application, everything should work.
486 @subsubsection Using shared libraries
488 This is how to create DLL and LIB files that are compatible with MSVC++:
492 @item Add a call to @file{vcvars32.bat} (which sets up the environment
493 variables for the Visual C++ tools) as the first line of @file{msys.bat}.
494 The standard location for @file{vcvars32.bat} is
495 @file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
496 and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
497 If this corresponds to your setup, add the following line as the first line
501 call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
504 Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
505 and run @file{c:\msys\1.0\msys.bat} from there.
507 @item Within the MSYS shell, run @code{lib.exe}. If you get a help message
508 from @file{Microsoft (R) Library Manager}, this means your environment
509 variables are set up correctly, the @file{Microsoft (R) Library Manager}
510 is on the path and will be used by FFmpeg to create
511 MSVC++-compatible import libraries.
513 @item Build FFmpeg with
516 ./configure --enable-shared --enable-memalign-hack
521 Your install path (@file{/usr/local/} by default) should now have the
522 necessary DLL and LIB files under the @file{bin} directory.
526 To use those files with MSVC++, do the same as you would do with
527 the static libraries, as described above. But in Step 4,
528 you should only need to add the directory where the LIB files are installed
529 (i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
530 installed in the @file{bin} directory. And instead of adding @file{libxx.a}
531 files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
532 @file{avutil.lib}. There should be no need for @file{libmingwex.a},
533 @file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
534 statically linked into the DLLs. The @file{bin} directory contains a bunch
535 of DLL files, but the ones that are actually used to run your application
536 are the ones with a major version number in their filenames
537 (i.e. @file{avcodec-51.dll}).
539 @subsection Cross compilation for Windows with Linux
541 You must use the MinGW cross compilation tools available at
542 @url{http://www.mingw.org/}.
544 Then configure FFmpeg with the following options:
546 ./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
548 (you can change the cross-prefix according to the prefix chosen for the
551 Then you can easily test FFmpeg with Wine
552 (@url{http://www.winehq.com/}).
554 @subsection Compilation under Cygwin
556 The main issue with Cygwin is that newlib, its C library, does not
557 contain llrint(). However, it is possible to leverage the
558 implementation in MinGW.
560 Just install your Cygwin with all the "Base" packages, plus the
561 following "Devel" ones:
563 binutils, gcc-core, make, subversion, mingw-runtime
566 Do not install binutils-20060709-1 (they are buggy on shared builds);
567 use binutils-20050610-1 instead.
569 Then create a small library that just contains llrint():
572 ar x /usr/lib/mingw/libmingwex.a llrint.o
573 ar cq /usr/local/lib/libllrint.a llrint.o
579 ./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
582 to make a static build or
585 ./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
588 to build shared libraries.
590 If you want to build FFmpeg with additional libraries, download Cygwin
591 "Devel" packages for Ogg and Vorbis from any Cygwin packages repository
592 and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
593 (@url{http://cygwinports.dotsrc.org/}).
595 @subsection Crosscompilation for Windows under Cygwin
597 With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
599 Just install your Cygwin as explained before, plus these additional
602 gcc-mingw-core, mingw-runtime, mingw-zlib
605 and add some special flags to your configure invocation.
607 For a static build run
609 ./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
612 and for a build with shared libraries
614 ./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
619 BeOS support is broken in mysterious ways.
623 For information about compiling FFmpeg on OS/2 see
624 @url{http://www.edm2.com/index.php/FFmpeg}.
626 @chapter Developers Guide
630 @item libavcodec is the library containing the codecs (both encoding and
631 decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
633 @item libavformat is the library containing the file format handling (mux and
634 demux code for several formats). Look at @file{ffplay.c} to use it in a
635 player. See @file{output_example.c} to use it to generate audio or video
640 @section Integrating libavcodec or libavformat in your program
642 You can integrate all the source code of the libraries to link them
643 statically to avoid any version problem. All you need is to provide a
644 'config.mak' and a 'config.h' in the parent directory. See the defines
645 generated by ./configure to understand what is needed.
647 You can use libavcodec or libavformat in your commercial program, but
648 @emph{any patch you make must be published}. The best way to proceed is
649 to send your patches to the FFmpeg mailing list.
652 @section Coding Rules
654 FFmpeg is programmed in the ISO C90 language with a few additional
655 features from ISO C99, namely:
658 the @samp{inline} keyword;
662 designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
664 compound literals (@samp{x = (struct s) @{ 17, 23 @};})
667 These features are supported by all compilers we care about, so we will not
668 accept patches to remove their use unless they absolutely do not impair
669 clarity and performance.
671 All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
672 compiles with several other compilers, such as the Compaq ccc compiler
673 or Sun Studio 9, and we would like to keep it that way unless it would
674 be exceedingly involved. To ensure compatibility, please do not use any
675 additional C99 features or GCC extensions. Especially watch out for:
678 mixing statements and declarations;
680 @samp{long long} (use @samp{int64_t} instead);
682 @samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
684 GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
688 The presentation is the one specified by 'indent -i4 -kr -nut'.
689 The TAB character is forbidden outside of Makefiles as is any
690 form of trailing whitespace. Commits containing either will be
691 rejected by the Subversion repository.
693 The main priority in FFmpeg is simplicity and small code size in order to
694 minimize the bug count.
696 Comments: Use the JavaDoc/Doxygen
697 format (see examples below) so that code documentation
698 can be generated automatically. All nontrivial functions should have a comment
699 above them explaining what the function does, even if it is just one sentence.
700 All structures and their member variables should be documented, too.
713 typedef struct Foobar@{
714 int var1; /**< var1 description */
715 int var2; ///< var2 description
716 /** var3 description */
724 * @@param my_parameter description of my_parameter
725 * @@return return value description
727 int myfunc(int my_parameter)
731 fprintf and printf are forbidden in libavformat and libavcodec,
732 please use av_log() instead.
734 Casts should be used only when necessary. Unneeded parentheses
735 should also be avoided if they don't make the code easier to understand.
737 @section Development Policy
741 Contributions should be licensed under the LGPL 2.1, including an
742 "or any later version" clause, or the MIT license. GPL 2 including
743 an "or any later version" clause is also acceptable, but LGPL is
746 You must not commit code which breaks FFmpeg! (Meaning unfinished but
747 enabled code which breaks compilation or compiles but does not work or
748 breaks the regression tests)
749 You can commit unfinished stuff (for testing etc), but it must be disabled
750 (#ifdef etc) by default so it does not interfere with other developers'
753 You do not have to over-test things. If it works for you, and you think it
754 should work for others, then commit. If your code has problems
755 (portability, triggers compiler bugs, unusual environment etc) they will be
756 reported and eventually fixed.
758 Do not commit unrelated changes together, split them into self-contained
759 pieces. Also do not forget that if part B depends on part A, but A does not
760 depend on B, then A can and should be committed first and separate from B.
761 Keeping changes well split into self-contained parts makes reviewing and
762 understanding them on the commit log mailing list easier. This also helps
763 in case of debugging later on.
764 Also if you have doubts about splitting or not splitting, do not hesitate to
765 ask/discuss it on the developer mailing list.
767 Do not change behavior of the program (renaming options etc) without
768 first discussing it on the ffmpeg-devel mailing list. Do not remove
769 functionality from the code. Just improve!
771 Note: Redundant code can be removed.
773 Do not commit changes to the build system (Makefiles, configure script)
774 which change behavior, defaults etc, without asking first. The same
775 applies to compiler warning fixes, trivial looking fixes and to code
776 maintained by other developers. We usually have a reason for doing things
777 the way we do. Send your changes as patches to the ffmpeg-devel mailing
778 list, and if the code maintainers say OK, you may commit. This does not
779 apply to files you wrote and/or maintain.
781 We refuse source indentation and other cosmetic changes if they are mixed
782 with functional changes, such commits will be rejected and removed. Every
783 developer has his own indentation style, you should not change it. Of course
784 if you (re)write something, you can use your own style, even though we would
785 prefer if the indentation throughout FFmpeg was consistent (Many projects
786 force a given indentation style - we do not.). If you really need to make
787 indentation changes (try to avoid this), separate them strictly from real
790 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
791 then either do NOT change the indentation of the inner part within (do not
792 move it to the right)! or do so in a separate commit
794 Always fill out the commit log message. Describe in a few lines what you
795 changed and why. You can refer to mailing list postings if you fix a
796 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
798 If you apply a patch by someone else, include the name and email address in
799 the log message. Since the ffmpeg-cvslog mailing list is publicly
800 archived you should add some SPAM protection to the email address. Send an
801 answer to ffmpeg-devel (or wherever you got the patch from) saying that
802 you applied the patch.
804 When applying patches that have been discussed (at length) on the mailing
805 list, reference the thread in the log message.
807 Do NOT commit to code actively maintained by others without permission.
808 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
809 timeframe (12h for build failures and security fixes, 3 days small changes,
810 1 week for big patches) then commit your patch if you think it is OK.
811 Also note, the maintainer can simply ask for more time to review!
813 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
814 are sent there and reviewed by all the other developers. Bugs and possible
815 improvements or general questions regarding commits are discussed there. We
816 expect you to react if problems with your code are uncovered.
818 Update the documentation if you change behavior or add features. If you are
819 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
820 maintainer(s) will review and commit your stuff.
822 Try to keep important discussions and requests (also) on the public
823 developer mailing list, so that all developers can benefit from them.
825 Never write to unallocated memory, never write over the end of arrays,
826 always check values read from some untrusted source before using them
827 as array index or other risky things.
829 Remember to check if you need to bump versions for the specific libav
830 parts (libavutil, libavcodec, libavformat) you are changing. You need
831 to change the version integer and the version string.
832 Incrementing the first component means no backward compatibility to
833 previous versions (e.g. removal of a function from the public API).
834 Incrementing the second component means backward compatible change
835 (e.g. addition of a function to the public API).
836 Incrementing the third component means a noteworthy binary compatible
837 change (e.g. encoder bug fix that matters for the decoder).
839 If you add a new codec, remember to update the changelog, add it to
840 the supported codecs table in the documentation and bump the second
841 component of the @file{libavcodec} version number appropriately. If
842 it has a fourcc, add it to @file{libavformat/riff.c}, even if it
845 Compiler warnings indicate potential bugs or code with bad style. If a type of
846 warning always points to correct and clean code, that warning should
847 be disabled, not the code changed.
848 Thus the remaining warnings can either be bugs or correct code.
849 If it is a bug, the bug has to be fixed. If it is not, the code should
850 be changed to not generate a warning unless that causes a slowdown
851 or obfuscates the code.
853 If you add a new file, give it a proper license header. Do not copy and
854 paste it from a random place, use an existing file as template.
857 We think our rules are not too hard. If you have comments, contact us.
859 Note, these rules are mostly borrowed from the MPlayer project.
861 @section Submitting patches
863 First, (@pxref{Coding Rules}) above if you did not yet.
865 When you submit your patch, try to send a unified diff (diff '-up'
866 option). We cannot read other diffs :-)
868 Also please do not submit a patch which contains several unrelated changes.
869 Split it into separate, self-contained pieces. This does not mean splitting
870 file by file. Instead, make the patch as small as possible while still
871 keeping it as a logical unit that contains an individual change, even
872 if it spans multiple files. This makes reviewing your patches much easier
873 for us and greatly increases your chances of getting your patch applied.
875 Run the regression tests before submitting a patch so that you can
876 verify that there are no big problems.
878 Patches should be posted as base64 encoded attachments (or any other
879 encoding which ensures that the patch will not be trashed during
880 transmission) to the ffmpeg-devel mailing list, see
881 @url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
883 It also helps quite a bit if you tell us what the patch does (for example
884 'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
887 Also please if you send several patches, send each patch as a separate mail,
888 do not attach several unrelated patches to the same mail.
890 @section patch submission checklist
894 Do the regression tests pass with the patch applied?
896 Is the patch a unified diff?
898 Is the patch against latest FFmpeg SVN?
900 Are you subscribed to ffmpeg-dev?
901 (the list is subscribers only due to spam)
903 Have you checked that the changes are minimal, so that the same cannot be
904 achieved with a smaller patch and/or simpler final code?
906 If the change is to speed critical code, did you benchmark it?
908 If you did any benchmarks, did you provide them in the mail?
910 Have you checked that the patch does not introduce buffer overflows or
911 other security issues?
913 If you add a new demuxer or decoder, have you checked that it does not
914 crash with damaged input (see tools/trasher)?
916 Is the patch created from the root of the source tree, so it can be
917 applied with @code{patch -p0}?
919 Does the patch not mix functional and cosmetic changes?
921 Did you add tabs or trailing whitespace to the code? Both are forbidden.
923 Is the patch attached to the email you send?
925 Is the mime type of the patch correct? It should be text/x-diff or
926 text/x-patch or at least text/plain and not application/octet-stream.
928 If the patch fixes a bug, did you provide a verbose analysis of the bug?
930 If the patch fixes a bug, did you provide enough information, including
931 a sample, so the bug can be reproduced and the fix can be verified?
932 Note please do not attach samples >100k to mails but rather provide a
933 URL, you can upload to ftp://upload.mplayerhq.hu
935 Did you provide a verbose summary about what the patch does change?
937 Did you provide a verbose explanation why it changes things like it does?
939 Did you provide a verbose summary of the user visible advantages and
940 disadvantages if the patch is applied?
942 Did you provide an example so we can verify the new feature added by the
945 If you added a new file, did you insert a license header? It should be
946 taken from FFmpeg, not randomly copied and pasted from somewhere else.
948 You should maintain alphabetical order in alphabetically ordered lists as
949 long as doing so does not break API/ABI compatibility.
951 Lines with similar content should be aligned vertically when doing so
952 improves readability.
954 Did you provide a suggestion for a clear commit log message?
956 Did you test your decoder or demuxer against damaged data? If no, see
957 tools/trasher and the noise bitstream filter. Your decoder or demuxer
958 should not crash or end in a (near) infinite loop when fed damaged data.
961 @section Patch review process
963 All patches posted to ffmpeg-devel will be reviewed, unless they contain a
964 clear note that the patch is not for SVN.
965 Reviews and comments will be posted as replies to the patch on the
966 mailing list. The patch submitter then has to take care of every comment,
967 that can be by resubmitting a changed patch or by discussion. Resubmitted
968 patches will themselves be reviewed like any other patch. If at some point
969 a patch passes review with no comments then it is approved, that can for
970 simple and small patches happen immediately while large patches will generally
971 have to be changed and reviewed many times before they are approved.
972 After a patch is approved it will be committed to the repository.
974 We will review all submitted patches, but sometimes we are quite busy so
975 especially for large patches this can take several weeks.
977 When resubmitting patches, please do not make any significant changes
978 not related to the comments received during review. Such patches will
979 be rejected. Instead, submit significant changes or new features as
982 @section Regression tests
984 Before submitting a patch (or committing to the repository), you should at least
985 test that you did not break anything.
987 The regression tests build a synthetic video stream and a synthetic
988 audio stream. These are then encoded and decoded with all codecs or
989 formats. The CRC (or MD5) of each generated file is recorded in a
990 result file. A 'diff' is launched to compare the reference results and
993 The regression tests then go on to test the FFserver code with a
994 limited set of streams. It is important that this step runs correctly
997 Run 'make test' to test all the codecs and formats.
999 Run 'make fulltest' to test all the codecs, formats and FFserver.
1001 [Of course, some patches may change the results of the regression tests. In
1002 this case, the reference results of the regression tests shall be modified