1\input texinfo @c -*- texinfo -*- 2 3@settitle General Documentation 4@titlepage 5@sp 7 6@center @titlefont{General Documentation} 7@sp 3 8@end titlepage 9 10 11@chapter external libraries 12 13FFmpeg can be hooked up with a number of external libraries to add support 14for more formats. None of them are used by default, their use has to be 15explicitly requested by passing the appropriate flags to @file{./configure}. 16 17@section AMR 18 19AMR comes in two different flavors, wideband and narrowband. FFmpeg can make 20use of the AMR wideband (floating-point mode) and the AMR narrowband 21(floating-point mode) reference decoders and encoders. 22 23Go to @url{http://www.penguin.cz/~utx/amr} and follow the instructions for 24installing the libraries. Then pass @code{--enable-libamr-nb} and/or 25@code{--enable-libamr-wb} to configure to enable the libraries. 26 27Note that libamr is copyrighted without any sort of license grant. This means 28that you can use it if you legally obtained it but you are not allowed to 29redistribute it in any way. @strong{Any FFmpeg binaries with libamr support 30you create are non-free and unredistributable!} 31 32 33@chapter Supported File Formats and Codecs 34 35You can use the @code{-formats} option to have an exhaustive list. 36 37@section File Formats 38 39FFmpeg supports the following file formats through the @code{libavformat} 40library: 41 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 73@item 4xm @tab @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 89@tab .fli/.flc files 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 CDROM 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 118different 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@end multitable 143 144@code{X} means that encoding (resp. decoding) is supported. 145 146@section Image Formats 147 148FFmpeg can read and write images for each frame of a video sequence. The 149following image formats are supported: 150 151@multitable @columnfractions .4 .1 .1 .4 152@item Supported Image Format @tab Encoding @tab Decoding @tab Comments 153@item PGM, PPM @tab X @tab X 154@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support. 155@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0 156@item JPEG @tab X @tab X @tab Progressive JPEG is not supported. 157@item .Y.U.V @tab X @tab X @tab one raw file per component 158@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated. 159@item PNG @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet. 160@item Targa @tab @tab X @tab Targa (.TGA) image format. 161@item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet. 162@item SGI @tab X @tab X @tab SGI RGB image format 163@item PTX @tab @tab X @tab V.Flash PTX format 164@item RAS @tab @tab X @tab Sun Rasterfile 165@item PCX @tab @tab X @tab PC Paintbrush 166@end multitable 167 168@code{X} means that encoding (resp. decoding) is supported. 169 170@section Video Codecs 171 172@multitable @columnfractions .4 .1 .1 .4 173@item Supported Codec @tab Encoding @tab Decoding @tab Comments 174@item MPEG-1 video @tab X @tab X 175@item MPEG-2 video @tab X @tab X 176@item MPEG-4 @tab X @tab X 177@item MSMPEG4 V1 @tab X @tab X 178@item MSMPEG4 V2 @tab X @tab X 179@item MSMPEG4 V3 @tab X @tab X 180@item WMV7 @tab X @tab X 181@item WMV8 @tab X @tab X @tab not completely working 182@item WMV9 @tab @tab X @tab not completely working 183@item VC1 @tab @tab X 184@item H.261 @tab X @tab X 185@item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0 186@item H.264 @tab @tab X 187@item RealVideo 1.0 @tab X @tab X 188@item RealVideo 2.0 @tab X @tab X 189@item MJPEG @tab X @tab X 190@item lossless MJPEG @tab X @tab X 191@item JPEG-LS @tab X @tab X @tab fourcc: MJLS, lossless and near-lossless is supported 192@item Apple MJPEG-B @tab @tab X 193@item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X 194@item DV @tab X @tab X 195@item HuffYUV @tab X @tab X 196@item FFmpeg Video 1 @tab X @tab X @tab experimental lossless codec (fourcc: FFV1) 197@item FFmpeg Snow @tab X @tab X @tab experimental wavelet codec (fourcc: SNOW) 198@item Asus v1 @tab X @tab X @tab fourcc: ASV1 199@item Asus v2 @tab X @tab X @tab fourcc: ASV2 200@item Creative YUV @tab @tab X @tab fourcc: CYUV 201@item Sorenson Video 1 @tab X @tab X @tab fourcc: SVQ1 202@item Sorenson Video 3 @tab @tab X @tab fourcc: SVQ3 203@item On2 VP3 @tab @tab X @tab still experimental 204@item On2 VP5 @tab @tab X @tab fourcc: VP50 205@item On2 VP6 @tab @tab X @tab fourcc: VP60,VP61,VP62 206@item Theora @tab X @tab X @tab still experimental 207@item Intel Indeo 3 @tab @tab X 208@item FLV @tab X @tab X @tab Sorenson H.263 used in Flash 209@item Flash Screen Video @tab X @tab X @tab fourcc: FSV1 210@item ATI VCR1 @tab @tab X @tab fourcc: VCR1 211@item ATI VCR2 @tab @tab X @tab fourcc: VCR2 212@item Cirrus Logic AccuPak @tab @tab X @tab fourcc: CLJR 213@item 4X Video @tab @tab X @tab Used in certain computer games. 214@item Sony Playstation MDEC @tab @tab X 215@item Id RoQ @tab X @tab X @tab Used in Quake III, Jedi Knight 2, other computer games. 216@item Xan/WC3 @tab @tab X @tab Used in Wing Commander III .MVE files. 217@item Interplay Video @tab @tab X @tab Used in Interplay .MVE files. 218@item Apple Animation @tab X @tab X @tab fourcc: 'rle ' 219@item Apple Graphics @tab @tab X @tab fourcc: 'smc ' 220@item Apple Video @tab @tab X @tab fourcc: rpza 221@item Apple QuickDraw @tab @tab X @tab fourcc: qdrw 222@item Cinepak @tab @tab X 223@item Microsoft RLE @tab @tab X 224@item Microsoft Video-1 @tab @tab X 225@item Westwood VQA @tab @tab X 226@item Id Cinematic Video @tab @tab X @tab Used in Quake II. 227@item Planar RGB @tab @tab X @tab fourcc: 8BPS 228@item FLIC video @tab @tab X 229@item Duck TrueMotion v1 @tab @tab X @tab fourcc: DUCK 230@item Duck TrueMotion v2 @tab @tab X @tab fourcc: TM20 231@item VMD Video @tab @tab X @tab Used in Sierra VMD files. 232@item MSZH @tab @tab X @tab Part of LCL 233@item ZLIB @tab X @tab X @tab Part of LCL, encoder experimental 234@item TechSmith Camtasia @tab @tab X @tab fourcc: TSCC 235@item IBM Ultimotion @tab @tab X @tab fourcc: ULTI 236@item Miro VideoXL @tab @tab X @tab fourcc: VIXL 237@item QPEG @tab @tab X @tab fourccs: QPEG, Q1.0, Q1.1 238@item LOCO @tab @tab X @tab 239@item Winnov WNV1 @tab @tab X @tab 240@item Autodesk Animator Studio Codec @tab @tab X @tab fourcc: AASC 241@item Fraps FPS1 @tab @tab X @tab 242@item CamStudio @tab @tab X @tab fourcc: CSCD 243@item American Laser Games Video @tab @tab X @tab Used in games like Mad Dog McCree 244@item ZMBV @tab X @tab X @tab Encoder works only on PAL8 245@item AVS Video @tab @tab X @tab Video encoding used by the Creature Shock game. 246@item Smacker Video @tab @tab X @tab Video encoding used in Smacker. 247@item RTjpeg @tab @tab X @tab Video encoding used in NuppelVideo files. 248@item KMVC @tab @tab X @tab Codec used in Worms games. 249@item VMware Video @tab @tab X @tab Codec used in videos captured by VMware. 250@item Cin Video @tab @tab X @tab Codec used in Delphine Software games. 251@item Tiertex Seq Video @tab @tab X @tab Codec used in DOS CDROM FlashBack game. 252@item DXA Video @tab @tab X @tab Codec originally used in Feeble Files game. 253@item AVID DNxHD @tab X @tab X @tab aka SMPTE VC3 254@item C93 Video @tab @tab X @tab Codec used in Cyberia game. 255@item THP @tab @tab X @tab Used on the Nintendo GameCube. 256@item Bethsoft VID @tab @tab X @tab Used in some games from Bethesda Softworks. 257@item Renderware TXD @tab @tab X @tab Texture dictionaries used by the Renderware Engine. 258@item AMV @tab @tab X @tab Used in Chinese MP3 players. 259@item Mimic @tab @tab X @tab Used in MSN Messenger Webcam streams. 260@end multitable 261 262@code{X} means that encoding (resp. decoding) is supported. 263 264@section Audio Codecs 265 266@multitable @columnfractions .4 .1 .1 .1 .7 267@item Supported Codec @tab Encoding @tab Decoding @tab Comments 268@item MPEG audio layer 2 @tab IX @tab IX 269@item MPEG audio layer 1/3 @tab X @tab IX 270@tab MP3 encoding is supported through the external library LAME. 271@item AC3 @tab IX @tab IX 272@tab liba52 is used internally for decoding. 273@item Vorbis @tab X @tab X 274@item WMA V1/V2 @tab X @tab X 275@item AAC @tab X @tab X 276@tab Supported through the external library libfaac/libfaad. 277@item Microsoft ADPCM @tab X @tab X 278@item AMV IMA ADPCM @tab @tab X 279@tab Used in AMV files 280@item MS IMA ADPCM @tab X @tab X 281@item QT IMA ADPCM @tab X @tab X 282@item 4X IMA ADPCM @tab @tab X 283@item G.726 ADPCM @tab X @tab X 284@item Duck DK3 IMA ADPCM @tab @tab X 285@tab Used in some Sega Saturn console games. 286@item Duck DK4 IMA ADPCM @tab @tab X 287@tab Used in some Sega Saturn console games. 288@item Westwood Studios IMA ADPCM @tab @tab X 289@tab Used in Westwood Studios games like Command and Conquer. 290@item SMJPEG IMA ADPCM @tab @tab X 291@tab Used in certain Loki game ports. 292@item CD-ROM XA ADPCM @tab @tab X 293@item CRI ADX ADPCM @tab X @tab X 294@tab Used in Sega Dreamcast games. 295@item Electronic Arts ADPCM @tab @tab X 296@tab Used in various EA titles. 297@item MAXIS EA ADPCM @tab @tab X 298@tab Used in Sim City 3000. 299@item Creative ADPCM @tab @tab X 300@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2 301@item THP ADPCM @tab @tab X 302@tab Used on the Nintendo GameCube. 303@item RA144 @tab @tab X 304@tab Real 14400 bit/s codec 305@item RA288 @tab @tab X 306@tab Real 28800 bit/s codec 307@item RADnet @tab X @tab IX 308@tab Real low bitrate AC3 codec, liba52 is used for decoding. 309@item AMR-NB @tab X @tab X 310@tab Supported through an external library. 311@item AMR-WB @tab X @tab X 312@tab Supported through an external library. 313@item DV audio @tab @tab X 314@item Id RoQ DPCM @tab X @tab X 315@tab Used in Quake III, Jedi Knight 2, other computer games. 316@item Interplay MVE DPCM @tab @tab X 317@tab Used in various Interplay computer games. 318@item Xan DPCM @tab @tab X 319@tab Used in Origin's Wing Commander IV AVI files. 320@item Sierra Online DPCM @tab @tab X 321@tab Used in Sierra Online game audio files. 322@item Apple MACE 3 @tab @tab X 323@item Apple MACE 6 @tab @tab X 324@item FLAC lossless audio @tab X @tab X 325@item Shorten lossless audio @tab @tab X 326@item Apple lossless audio @tab @tab X 327@tab QuickTime fourcc 'alac' 328@item FFmpeg Sonic @tab X @tab X 329@tab experimental lossy/lossless codec 330@item Qdesign QDM2 @tab @tab X 331@tab there are still some distortions 332@item Real COOK @tab @tab X 333@tab All versions except 5.1 are supported 334@item DSP Group TrueSpeech @tab @tab X 335@item True Audio (TTA) @tab @tab X 336@item Smacker Audio @tab @tab X 337@item WavPack Audio @tab @tab X 338@item Cin Audio @tab @tab X 339@tab Codec used in Delphine Software games. 340@item Intel Music Coder @tab @tab X 341@item Musepack @tab @tab X 342@tab SV7 and SV8 are supported 343@item DT$ Coherent Audio @tab @tab X 344@item ATRAC 3 @tab @tab X 345@item Monkey's Audio @tab @tab X @tab Only versions 3.97-3.99 are supported 346@item Nellymoser ASAO @tab @tab X 347@item 8SVX Audio @tab @tab X 348@end multitable 349 350@code{X} means that encoding (resp. decoding) is supported. 351 352@code{I} means that an integer-only version is available, too (ensures high 353performance on systems without hardware floating point support). 354 355@chapter Platform Specific information 356 357@section BSD 358 359BSD make will not build FFmpeg, you need to install and use GNU Make 360(@file{gmake}). 361 362@section Windows 363 364To get help and instructions for building FFmpeg under Windows, check out 365the FFmpeg Windows Help Forum at 366@url{http://arrozcru.no-ip.org/ffmpeg/}. 367 368@subsection Native Windows compilation 369 370FFmpeg can be built to run natively on Windows using the MinGW tools. Install 371the current versions of MSYS and MinGW from @url{http://www.mingw.org/}. Also 372install the coreutils package, and update to the latest MSYS make (note: not 373mingw32-make). You can find detailed installation 374instructions in the download section and the FAQ. 375 376Within the MSYS shell, configure and make with: 377 378@example 379./configure --enable-memalign-hack 380make 381make install 382@end example 383 384This will install @file{ffmpeg.exe} along with many other development files 385to @file{/usr/local}. You may specify another install path using the 386@code{--prefix} option in @file{configure}. 387 388Notes: 389 390@itemize 391 392@item Use at least bash 3.1. Older versions are known to fail on the 393configure script. 394 395@item In order to compile vhooks, you must have a POSIX-compliant libdl in 396your MinGW system. Get dlfcn-win32 from 397@url{http://code.google.com/p/dlfcn-win32}. 398 399@item In order to compile FFplay, you must have the MinGW development library 400of SDL. Get it from @url{http://www.libsdl.org}. 401Edit the @file{bin/sdl-config} script so that it points to the correct prefix 402where SDL was installed. Verify that @file{sdl-config} can be launched from 403the MSYS command line. 404 405@item By using @code{./configure --enable-shared} when configuring FFmpeg, 406you can build libavutil, libavcodec and libavformat as DLLs. 407 408@end itemize 409 410@subsection Microsoft Visual C++ compatibility 411 412As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you 413want to use the libav* libraries in your own applications, you can still 414compile those applications using MSVC++. But the libav* libraries you link 415to @emph{must} be built with MinGW. However, you will not be able to debug 416inside the libav* libraries, since MSVC++ does not recognize the debug 417symbols generated by GCC. 418We strongly recommend you to move over from MSVC++ to MinGW tools. 419 420This description of how to use the FFmpeg libraries with MSVC++ is based on 421Microsoft Visual C++ 2005 Express Edition. If you have a different version, 422you might have to modify the procedures slightly. 423 424@subsubsection Using static libraries 425 426Assuming you have just built and installed FFmpeg in @file{/usr/local}. 427 428@enumerate 429 430@item Create a new console application ("File / New / Project") and then 431select "Win32 Console Application". On the appropriate page of the 432Application Wizard, uncheck the "Precompiled headers" option. 433 434@item Write the source code for your application, or, for testing, just 435copy the code from an existing sample application into the source file 436that MSVC++ has already created for you. For example, you can copy 437@file{output_example.c} from the FFmpeg distribution. 438 439@item Open the "Project / Properties" dialog box. In the "Configuration" 440combo box, select "All Configurations" so that the changes you make will 441affect both debug and release builds. In the tree view on the left hand 442side, select "C/C++ / General", then edit the "Additional Include 443Directories" setting to contain the path where the FFmpeg includes were 444installed (i.e. @file{c:\msys\1.0\local\include}). 445 446@item Still in the "Project / Properties" dialog box, select 447"Linker / General" from the tree view and edit the 448"Additional Library Directories" setting to contain the @file{lib} 449directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}), 450the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}), 451and the directory where MinGW's GCC libs are installed 452(i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select 453"Linker / Input" from the tree view, and add the files @file{libavformat.a}, 454@file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a}, 455@file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a}) 456to the end of "Additional Dependencies". 457 458@item Now, select "C/C++ / Code Generation" from the tree view. Select 459"Debug" in the "Configuration" combo box. Make sure that "Runtime 460Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in 461the "Configuration" combo box and make sure that "Runtime Library" is 462set to "Multi-threaded DLL". 463 464@item Click "OK" to close the "Project / Properties" dialog box. 465 466@item MSVC++ lacks some C99 header files that are fundamental for FFmpeg. 467Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list} 468and install it in MSVC++'s include directory 469(i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}). 470 471@item MSVC++ also does not understand the @code{inline} keyword used by 472FFmpeg, so you must add this line before @code{#include}ing libav*: 473@example 474#define inline _inline 475@end example 476 477@item If you used @file{output_example.c} as your sample application, 478you will have to edit the @code{#include}s to point to the files which 479are under the @file{ffmpeg} directory (i.e. @code{<ffmpeg/avformat.h>}). 480 481@item Build your application, everything should work. 482 483@end enumerate 484 485@subsubsection Using shared libraries 486 487This is how to create DLL and LIB files that are compatible with MSVC++: 488 489@enumerate 490 491@item Add a call to @file{vcvars32.bat} (which sets up the environment 492variables for the Visual C++ tools) as the first line of @file{msys.bat}. 493The standard location for @file{vcvars32.bat} is 494@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat}, 495and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}. 496If this corresponds to your setup, add the following line as the first line 497of @file{msys.bat}: 498 499@example 500call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat" 501@end example 502 503Alternatively, you may start the @file{Visual Studio 2005 Command Prompt}, 504and run @file{c:\msys\1.0\msys.bat} from there. 505 506@item Within the MSYS shell, run @code{lib.exe}. If you get a help message 507from @file{Microsoft (R) Library Manager}, this means your environment 508variables are set up correctly, the @file{Microsoft (R) Library Manager} 509is on the path and will be used by FFmpeg to create 510MSVC++-compatible import libraries. 511 512@item Build FFmpeg with 513 514@example 515./configure --enable-shared --enable-memalign-hack 516make 517make install 518@end example 519 520Your install path (@file{/usr/local/} by default) should now have the 521necessary DLL and LIB files under the @file{bin} directory. 522 523@end enumerate 524 525To use those files with MSVC++, do the same as you would do with 526the static libraries, as described above. But in Step 4, 527you should only need to add the directory where the LIB files are installed 528(i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are 529installed in the @file{bin} directory. And instead of adding @file{libxx.a} 530files, you should add @file{avcodec.lib}, @file{avformat.lib}, and 531@file{avutil.lib}. There should be no need for @file{libmingwex.a}, 532@file{libgcc.a}, and @file{wsock32.lib}, nor any other external library 533statically linked into the DLLs. The @file{bin} directory contains a bunch 534of DLL files, but the ones that are actually used to run your application 535are the ones with a major version number in their filenames 536(i.e. @file{avcodec-51.dll}). 537 538@subsection Cross compilation for Windows with Linux 539 540You must use the MinGW cross compilation tools available at 541@url{http://www.mingw.org/}. 542 543Then configure FFmpeg with the following options: 544@example 545./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc- 546@end example 547(you can change the cross-prefix according to the prefix chosen for the 548MinGW tools). 549 550Then you can easily test FFmpeg with Wine 551(@url{http://www.winehq.com/}). 552 553@subsection Compilation under Cygwin 554 555The main issue with Cygwin is that newlib, its C library, does not 556contain llrint(). However, it is possible to leverage the 557implementation in MinGW. 558 559Just install your Cygwin with all the "Base" packages, plus the 560following "Devel" ones: 561@example 562binutils, gcc-core, make, subversion, mingw-runtime 563@end example 564 565Do not install binutils-20060709-1 (they are buggy on shared builds); 566use binutils-20050610-1 instead. 567 568Then create a small library that just contains llrint(): 569 570@example 571ar x /usr/lib/mingw/libmingwex.a llrint.o 572ar cq /usr/local/lib/libllrint.a llrint.o 573@end example 574 575Then run 576 577@example 578./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint' 579@end example 580 581to make a static build or 582 583@example 584./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint' 585@end example 586 587to build shared libraries. 588 589If you want to build FFmpeg with additional libraries, download Cygwin 590"Devel" packages for Ogg and Vorbis from any Cygwin packages repository 591and/or SDL, xvid, faac, faad2 packages from Cygwin Ports, 592(@url{http://cygwinports.dotsrc.org/}). 593 594@subsection Crosscompilation for Windows under Cygwin 595 596With Cygwin you can create Windows binaries that do not need the cygwin1.dll. 597 598Just install your Cygwin as explained before, plus these additional 599"Devel" packages: 600@example 601gcc-mingw-core, mingw-runtime, mingw-zlib 602@end example 603 604and add some special flags to your configure invocation. 605 606For a static build run 607@example 608./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin 609@end example 610 611and for a build with shared libraries 612@example 613./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin 614@end example 615 616@section BeOS 617 618BeOS support is broken in mysterious ways. 619 620@section OS/2 621 622For information about compiling FFmpeg on OS/2 see 623@url{http://www.edm2.com/index.php/FFmpeg}. 624 625@chapter Developers Guide 626 627@section API 628@itemize @bullet 629@item libavcodec is the library containing the codecs (both encoding and 630decoding). Look at @file{libavcodec/apiexample.c} to see how to use it. 631 632@item libavformat is the library containing the file format handling (mux and 633demux code for several formats). Look at @file{ffplay.c} to use it in a 634player. See @file{output_example.c} to use it to generate audio or video 635streams. 636 637@end itemize 638 639@section Integrating libavcodec or libavformat in your program 640 641You can integrate all the source code of the libraries to link them 642statically to avoid any version problem. All you need is to provide a 643'config.mak' and a 'config.h' in the parent directory. See the defines 644generated by ./configure to understand what is needed. 645 646You can use libavcodec or libavformat in your commercial program, but 647@emph{any patch you make must be published}. The best way to proceed is 648to send your patches to the FFmpeg mailing list. 649 650@node Coding Rules 651@section Coding Rules 652 653FFmpeg is programmed in the ISO C90 language with a few additional 654features from ISO C99, namely: 655@itemize @bullet 656@item 657the @samp{inline} keyword; 658@item 659@samp{//} comments; 660@item 661designated struct initializers (@samp{struct s x = @{ .i = 17 @};}) 662@item 663compound literals (@samp{x = (struct s) @{ 17, 23 @};}) 664@end itemize 665 666These features are supported by all compilers we care about, so we will not 667accept patches to remove their use unless they absolutely do not impair 668clarity and performance. 669 670All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also 671compiles with several other compilers, such as the Compaq ccc compiler 672or Sun Studio 9, and we would like to keep it that way unless it would 673be exceedingly involved. To ensure compatibility, please do not use any 674additional C99 features or GCC extensions. Especially watch out for: 675@itemize @bullet 676@item 677mixing statements and declarations; 678@item 679@samp{long long} (use @samp{int64_t} instead); 680@item 681@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar; 682@item 683GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}). 684@end itemize 685 686Indent size is 4. 687The presentation is the one specified by 'indent -i4 -kr -nut'. 688The TAB character is forbidden outside of Makefiles as is any 689form of trailing whitespace. Commits containing either will be 690rejected by the Subversion repository. 691 692The main priority in FFmpeg is simplicity and small code size in order to 693minimize the bug count. 694 695Comments: Use the JavaDoc/Doxygen 696format (see examples below) so that code documentation 697can be generated automatically. All nontrivial functions should have a comment 698above them explaining what the function does, even if it is just one sentence. 699All structures and their member variables should be documented, too. 700@example 701/** 702 * @@file mpeg.c 703 * MPEG codec. 704 * @@author ... 705 */ 706 707/** 708 * Summary sentence. 709 * more text ... 710 * ... 711 */ 712typedef struct Foobar@{ 713 int var1; /**< var1 description */ 714 int var2; ///< var2 description 715 /** var3 description */ 716 int var3; 717@} Foobar; 718 719/** 720 * Summary sentence. 721 * more text ... 722 * ... 723 * @@param my_parameter description of my_parameter 724 * @@return return value description 725 */ 726int myfunc(int my_parameter) 727... 728@end example 729 730fprintf and printf are forbidden in libavformat and libavcodec, 731please use av_log() instead. 732 733Casts should be used only when necessary. Unneeded parentheses 734should also be avoided if they don't make the code easier to understand. 735 736@section Development Policy 737 738@enumerate 739@item 740 Contributions should be licensed under the LGPL 2.1, including an 741 "or any later version" clause, or the MIT license. GPL 2 including 742 an "or any later version" clause is also acceptable, but LGPL is 743 preferred. 744@item 745 You must not commit code which breaks FFmpeg! (Meaning unfinished but 746 enabled code which breaks compilation or compiles but does not work or 747 breaks the regression tests) 748 You can commit unfinished stuff (for testing etc), but it must be disabled 749 (#ifdef etc) by default so it does not interfere with other developers' 750 work. 751@item 752 You do not have to over-test things. If it works for you, and you think it 753 should work for others, then commit. If your code has problems 754 (portability, triggers compiler bugs, unusual environment etc) they will be 755 reported and eventually fixed. 756@item 757 Do not commit unrelated changes together, split them into self-contained 758 pieces. Also do not forget that if part B depends on part A, but A does not 759 depend on B, then A can and should be committed first and separate from B. 760 Keeping changes well split into self-contained parts makes reviewing and 761 understanding them on the commit log mailing list easier. This also helps 762 in case of debugging later on. 763 Also if you have doubts about splitting or not splitting, do not hesitate to 764 ask/discuss it on the developer mailing list. 765@item 766 Do not change behavior of the program (renaming options etc) without 767 first discussing it on the ffmpeg-devel mailing list. Do not remove 768 functionality from the code. Just improve! 769 770 Note: Redundant code can be removed. 771@item 772 Do not commit changes to the build system (Makefiles, configure script) 773 which change behavior, defaults etc, without asking first. The same 774 applies to compiler warning fixes, trivial looking fixes and to code 775 maintained by other developers. We usually have a reason for doing things 776 the way we do. Send your changes as patches to the ffmpeg-devel mailing 777 list, and if the code maintainers say OK, you may commit. This does not 778 apply to files you wrote and/or maintain. 779@item 780 We refuse source indentation and other cosmetic changes if they are mixed 781 with functional changes, such commits will be rejected and removed. Every 782 developer has his own indentation style, you should not change it. Of course 783 if you (re)write something, you can use your own style, even though we would 784 prefer if the indentation throughout FFmpeg was consistent (Many projects 785 force a given indentation style - we do not.). If you really need to make 786 indentation changes (try to avoid this), separate them strictly from real 787 changes. 788 789 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code, 790 then either do NOT change the indentation of the inner part within (do not 791 move it to the right)! or do so in a separate commit 792@item 793 Always fill out the commit log message. Describe in a few lines what you 794 changed and why. You can refer to mailing list postings if you fix a 795 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable. 796@item 797 If you apply a patch by someone else, include the name and email address in 798 the log message. Since the ffmpeg-cvslog mailing list is publicly 799 archived you should add some SPAM protection to the email address. Send an 800 answer to ffmpeg-devel (or wherever you got the patch from) saying that 801 you applied the patch. 802@item 803 When applying patches that have been discussed (at length) on the mailing 804 list, reference the thread in the log message. 805@item 806 Do NOT commit to code actively maintained by others without permission. 807 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable 808 timeframe (12h for build failures and security fixes, 3 days small changes, 809 1 week for big patches) then commit your patch if you think it is OK. 810 Also note, the maintainer can simply ask for more time to review! 811@item 812 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits 813 are sent there and reviewed by all the other developers. Bugs and possible 814 improvements or general questions regarding commits are discussed there. We 815 expect you to react if problems with your code are uncovered. 816@item 817 Update the documentation if you change behavior or add features. If you are 818 unsure how best to do this, send a patch to ffmpeg-devel, the documentation 819 maintainer(s) will review and commit your stuff. 820@item 821 Try to keep important discussions and requests (also) on the public 822 developer mailing list, so that all developers can benefit from them. 823@item 824 Never write to unallocated memory, never write over the end of arrays, 825 always check values read from some untrusted source before using them 826 as array index or other risky things. 827@item 828 Remember to check if you need to bump versions for the specific libav 829 parts (libavutil, libavcodec, libavformat) you are changing. You need 830 to change the version integer and the version string. 831 Incrementing the first component means no backward compatibility to 832 previous versions (e.g. removal of a function from the public API). 833 Incrementing the second component means backward compatible change 834 (e.g. addition of a function to the public API). 835 Incrementing the third component means a noteworthy binary compatible 836 change (e.g. encoder bug fix that matters for the decoder). 837@item 838 If you add a new codec, remember to update the changelog, add it to 839 the supported codecs table in the documentation and bump the second 840 component of the @file{libavcodec} version number appropriately. If 841 it has a fourcc, add it to @file{libavformat/avienc.c}, even if it 842 is only a decoder. 843@item 844 Compiler warnings indicate potential bugs or code with bad style. If a type of 845 warning always points to correct and clean code, that warning should 846 be disabled, not the code changed. 847 Thus the remaining warnings can either be bugs or correct code. 848 If it is a bug, the bug has to be fixed. If it is not, the code should 849 be changed to not generate a warning unless that causes a slowdown 850 or obfuscates the code. 851@item 852 If you add a new file, give it a proper license header. Do not copy and 853 paste it from a random place, use an existing file as template. 854@end enumerate 855 856We think our rules are not too hard. If you have comments, contact us. 857 858Note, these rules are mostly borrowed from the MPlayer project. 859 860@section Submitting patches 861 862First, (@pxref{Coding Rules}) above if you did not yet. 863 864When you submit your patch, try to send a unified diff (diff '-up' 865option). We cannot read other diffs :-) 866 867Also please do not submit a patch which contains several unrelated changes. 868Split it into separate, self-contained pieces. This does not mean splitting 869file by file. Instead, make the patch as small as possible while still 870keeping it as a logical unit that contains an individual change, even 871if it spans multiple files. This makes reviewing your patches much easier 872for us and greatly increases your chances of getting your patch applied. 873 874Run the regression tests before submitting a patch so that you can 875verify that there are no big problems. 876 877Patches should be posted as base64 encoded attachments (or any other 878encoding which ensures that the patch will not be trashed during 879transmission) to the ffmpeg-devel mailing list, see 880@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel} 881 882It also helps quite a bit if you tell us what the patch does (for example 883'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant 884and has no lrint()') 885 886Also please if you send several patches, send each patch as a separate mail, 887do not attach several unrelated patches to the same mail. 888 889@section patch submission checklist 890 891@enumerate 892@item 893 Do the regression tests pass with the patch applied? 894@item 895 Is the patch a unified diff? 896@item 897 Is the patch against latest FFmpeg SVN? 898@item 899 Are you subscribed to ffmpeg-dev? 900 (the list is subscribers only due to spam) 901@item 902 Have you checked that the changes are minimal, so that the same cannot be 903 achieved with a smaller patch and/or simpler final code? 904@item 905 If the change is to speed critical code, did you benchmark it? 906@item 907 If you did any benchmarks, did you provide them in the mail? 908@item 909 Have you checked that the patch does not introduce buffer overflows or 910 other security issues? 911@item 912 If you add a new demuxer or decoder, have you checked that it does not 913 crash with damaged input (see tools/trasher)? 914@item 915 Is the patch created from the root of the source tree, so it can be 916 applied with @code{patch -p0}? 917@item 918 Does the patch not mix functional and cosmetic changes? 919@item 920 Did you add tabs or trailing whitespace to the code? Both are forbidden. 921@item 922 Is the patch attached to the email you send? 923@item 924 Is the mime type of the patch correct? It should be text/x-diff or 925 text/x-patch or at least text/plain and not application/octet-stream. 926@item 927 If the patch fixes a bug, did you provide a verbose analysis of the bug? 928@item 929 If the patch fixes a bug, did you provide enough information, including 930 a sample, so the bug can be reproduced and the fix can be verified? 931 Note please do not attach samples >100k to mails but rather provide a 932 URL, you can upload to ftp://upload.mplayerhq.hu 933@item 934 Did you provide a verbose summary about what the patch does change? 935@item 936 Did you provide a verbose explanation why it changes things like it does? 937@item 938 Did you provide a verbose summary of the user visible advantages and 939 disadvantages if the patch is applied? 940@item 941 Did you provide an example so we can verify the new feature added by the 942 patch easily? 943@item 944 If you added a new file, did you insert a license header? It should be 945 taken from FFmpeg, not randomly copied and pasted from somewhere else. 946@item 947 You should maintain alphabetical order in alphabetically ordered lists as 948 long as doing so does not break API/ABI compatibility. 949@item 950 Lines with similar content should be aligned vertically when doing so 951 improves readability. 952@item 953 Did you provide a suggestion for a clear commit log message? 954@item 955 Did you test your decoder or demuxer against damaged data? If no, see 956 tools/trasher and the noise bitstream filter. Your decoder or demuxer 957 should not crash or end in a (near) infinite loop when fed damaged data. 958@end enumerate 959 960@section Patch review process 961 962All patches posted to ffmpeg-devel will be reviewed, unless they contain a 963clear note that the patch is not for SVN. 964Reviews and comments will be posted as replies to the patch on the 965mailing list. The patch submitter then has to take care of every comment, 966that can be by resubmitting a changed patch or by discussion. Resubmitted 967patches will themselves be reviewed like any other patch. If at some point 968a patch passes review with no comments then it is approved, that can for 969simple and small patches happen immediately while large patches will generally 970have to be changed and reviewed many times before they are approved. 971After a patch is approved it will be committed to the repository. 972 973We will review all submitted patches, but sometimes we are quite busy so 974especially for large patches this can take several weeks. 975 976When resubmitting patches, please do not make any significant changes 977not related to the comments received during review. Such patches will 978be rejected. Instead, submit significant changes or new features as 979separate patches. 980 981@section Regression tests 982 983Before submitting a patch (or committing to the repository), you should at least 984test that you did not break anything. 985 986The regression tests build a synthetic video stream and a synthetic 987audio stream. These are then encoded and decoded with all codecs or 988formats. The CRC (or MD5) of each generated file is recorded in a 989result file. A 'diff' is launched to compare the reference results and 990the result file. 991 992The regression tests then go on to test the FFserver code with a 993limited set of streams. It is important that this step runs correctly 994as well. 995 996Run 'make test' to test all the codecs and formats. 997 998Run 'make fulltest' to test all the codecs, formats and FFserver. 999 1000[Of course, some patches may change the results of the regression tests. In 1001this case, the reference results of the regression tests shall be modified 1002accordingly]. 1003 1004@bye 1005