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[libav.git] / doc / general.texi
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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
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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.
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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
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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
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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
b3de4544 43@item Name @tab Encoding @tab Decoding @tab Comments
64c2f20a 44@item 4xm @tab @tab X
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45 @tab 4X Technologies format, used in some games.
46@item ADTS AAC audio @tab X @tab X
39271be4 47@item Audio IFF (AIFF) @tab X @tab X
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48@item American Laser Games MM @tab @tab X
49 @tab Multimedia format used in games like Mad Dog McCree.
39271be4 50@item 3GPP AMR @tab X @tab X
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51@item ASF @tab X @tab X
52@item AVI @tab X @tab X
39271be4 53@item AVISynth @tab @tab X
c6b2dc34 54@item AVS @tab @tab X
d698c5d3 55 @tab Multimedia format used by the Creature Shock game.
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56@item Beam Software SIFF @tab @tab X
57 @tab Audio and video format used in some games by Beam Software.
58@item Bethesda Softworks VID @tab @tab X
d698c5d3 59 @tab Used in some games from Bethesda Softworks.
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60@item Brute Force & Ignorance @tab @tab X
61 @tab Used in the game Flash Traffic: City of Angels.
62@item Interplay C93 @tab @tab X
d698c5d3 63 @tab Used in the game Cyberia from Interplay.
913c3e2c 64@item Delphine Software International CIN @tab @tab X
d698c5d3 65 @tab Multimedia format used by Delphine Software games.
39271be4 66@item CRC testing format @tab X @tab
913c3e2c 67@item Creative Voice @tab X @tab X
d698c5d3 68 @tab Created for the Sound Blaster Pro.
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69@item CRYO APC @tab @tab X
70 @tab Audio format used in some games by CRYO Interactive Entertainment.
39271be4 71@item D-Cinema audio @tab X @tab X
913c3e2c 72@item DV video @tab X @tab X
c6b2dc34 73@item DXA @tab @tab X
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74 @tab This format is used in the non-Windows version of the Feeble Files
75 game and different game cutscenes repacked for use with ScummVM.
39271be4 76@item Electronic Arts cdata @tab @tab X
c6b2dc34 77@item Electronic Arts Multimedia @tab @tab X
d698c5d3 78 @tab Used in various EA games; files have extensions like WVE and UV2.
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79@item FFM (FFserver live feed) @tab X @tab X
80@item Flash (SWF) @tab X @tab X
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81@item Flash 9 (AVM2) @tab X @tab X
82 @tab Only embedded audio is decoded.
83@item FLI/FLC/FLX animation @tab @tab X
d698c5d3 84 @tab .fli/.flc files
c6b2dc34 85@item FLV @tab X @tab X
d698c5d3 86 @tab Macromedia Flash video files
39271be4 87@item framecrc testing format @tab X @tab
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88@item FunCom ISS @tab @tab X
89 @tab Audio format used in various games from FunCom like The Longest Journey.
39271be4 90@item GIF Animation @tab X @tab
c6b2dc34 91@item GXF @tab X @tab X
d698c5d3 92 @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley
64c2f20a 93 playout servers.
76ec3939 94@item id Cinematic @tab @tab X
d698c5d3 95 @tab Used in Quake II.
76ec3939 96@item id RoQ @tab X @tab X
d698c5d3 97 @tab Used in Quake III, Jedi Knight 2, other computer games.
c6b2dc34 98@item IFF @tab @tab X
d698c5d3 99 @tab Interchange File Format
c6b2dc34 100@item Interplay MVE @tab @tab X
d698c5d3 101 @tab Format used in various Interplay computer games.
c6b2dc34 102@item LMLM4 @tab @tab X
d698c5d3 103 @tab Used by Linux Media Labs MPEG-4 PCI boards
64c2f20a 104@item Matroska @tab X @tab X
39271be4 105@item Matroska audio @tab X @tab
913c3e2c 106@item MAXIS XA @tab @tab X
d698c5d3 107 @tab Used in Sim City 3000; file extension .xa.
64c2f20a 108@item Monkey's Audio @tab @tab X
822cc8f7 109@item Motion Pixels MVI @tab @tab X
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110@item MOV/QuickTime/MP4 @tab X @tab X
111 @tab 3GP, 3GP2, PSP, iPod variants supported
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112@item MP2 @tab X @tab
113@item MP3 @tab X @tab
c6b2dc34 114@item MPEG audio @tab X @tab X
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115@item MPEG-1 System @tab X @tab X
116 @tab muxed audio and video, VCD format supported
117@item MPEG-PS (program stream) @tab X @tab X
118 @tab also known as @code{VOB} file, SVCD and DVD format supported
119@item MPEG-TS (transport stream) @tab X @tab X
d698c5d3 120 @tab also known as DVB Transport Stream
c6b2dc34 121@item MPEG-4 @tab X @tab X
d698c5d3 122 @tab MPEG-4 is a variant of QuickTime.
39271be4 123@item MIME multipart JPEG @tab X @tab
bac4c85c 124@item MSN TCP webcam @tab @tab X
d698c5d3 125 @tab Used by MSN Messenger webcam streams.
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126@item MTV @tab @tab X
127@item Musepack @tab @tab X
128@item Musepack SV8 @tab @tab X
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129@item Material eXchange Format (MXF) @tab X @tab X
130 @tab SMPTE 377M, used by D-Cinema, broadcast industry.
131@item NC camera feed @tab @tab X
132 @tab NC (AVIP NC4600) camera streams
133@item Nullsoft Streaming Video @tab @tab X
39271be4 134@item NuppelVideo @tab @tab X
c6b2dc34 135@item NUT @tab X @tab X
d698c5d3 136 @tab NUT Open Container Format
39271be4 137@item Ogg @tab X @tab X
913c3e2c 138@item TechnoTrend PVA @tab @tab X
d698c5d3 139 @tab Used by TechnoTrend DVB PCI boards.
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140@item raw AC-3 @tab X @tab X
141@item raw CRI ADX audio @tab X @tab X
142@item raw MJPEG @tab X @tab X
143@item raw MPEG video @tab X @tab X
144@item raw MPEG-4 video @tab X @tab X
eb6fc557 145@item raw PCM 8/16/32 bits, 32/64-bit floating point, mu-law/A-law @tab X @tab X
76ec3939 146@item raw Shorten audio @tab @tab X
39271be4 147@item RDT @tab @tab X
913c3e2c 148@item REDCODE R3D @tab @tab X
7eb68edb 149 @tab File format used by RED Digital cameras, contains JPEG 2000 frames and PCM audio.
64c2f20a 150@item RealMedia @tab X @tab X
39271be4 151@item Redirector @tab @tab X
913c3e2c 152@item Renderware TeXture Dictionary @tab @tab X
c6b2dc34 153@item RL2 @tab @tab X
d698c5d3 154 @tab Audio and video format used in some games by Entertainment Software Partners.
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155@item RPL/ARMovie @tab @tab X
156@item RTP @tab @tab X
157@item RTSP @tab @tab X
158@item SDP @tab @tab X
c6b2dc34 159@item Sega FILM/CPK @tab @tab X
d698c5d3 160 @tab Used in many Sega Saturn console games.
913c3e2c 161@item Sierra SOL @tab @tab X
d698c5d3 162 @tab .sol files used in Sierra Online games.
c6b2dc34 163@item Sierra VMD @tab @tab X
d698c5d3 164 @tab Used in Sierra CD-ROM games.
c6b2dc34 165@item Smacker @tab @tab X
d698c5d3 166 @tab Multimedia format used by many games.
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167@item Sony OpenMG (OMA) @tab @tab X
168 @tab Audio format used in Sony Sonic Stage and Sony Vegas.
169@item Sony PlayStation STR @tab @tab X
64c2f20a 170@item SUN AU format @tab X @tab X
c6b2dc34 171@item THP @tab @tab X
d698c5d3 172 @tab Used on the Nintendo GameCube.
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173@item Tiertex Limited SEQ @tab @tab X
174 @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
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175@item True Audio @tab @tab X
176@item VC-1 test bitstream @tab X @tab X
c6b2dc34 177@item WAV @tab X @tab X
39271be4 178@item WavPack @tab @tab X
913c3e2c 179@item Wing Commander III movie @tab @tab X
d698c5d3 180 @tab Multimedia format used in Origin's Wing Commander III computer game.
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181@item Westwood Studios audio @tab @tab X
182 @tab Multimedia format used in Westwood Studios games.
183@item Westwood Studios VQA @tab @tab X
184 @tab Multimedia format used in Westwood Studios games.
39271be4 185@item YUV4MPEG pipe @tab X @tab X
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186@end multitable
187
188@code{X} means that encoding (resp. decoding) is supported.
189
190@section Image Formats
191
192FFmpeg can read and write images for each frame of a video sequence. The
193following image formats are supported:
194
195@multitable @columnfractions .4 .1 .1 .4
b3de4544 196@item Name @tab Encoding @tab Decoding @tab Comments
64c2f20a 197@item .Y.U.V @tab X @tab X @tab one raw file per component
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198@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
199@item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
9a77d59a 200@item JPEG 2000 @tab @tab E @tab decoding supported through external library libopenjpeg
d0e1cd3d 201@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
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202@item PCX @tab @tab X @tab PC Paintbrush
203@item PGM, PPM @tab X @tab X
d0e1cd3d 204@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
0a91f4ee 205@item PNG @tab X @tab X @tab 2/4 bpp not supported yet
d0e1cd3d 206@item PTX @tab @tab X @tab V.Flash PTX format
d1928ac1 207@item RAS @tab @tab X @tab Sun Rasterfile
3d172fb5 208@item SGI @tab X @tab X @tab SGI RGB image format
3d172fb5 209@item Targa @tab @tab X @tab Targa (.TGA) image format
64c2f20a 210@item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
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211@end multitable
212
213@code{X} means that encoding (resp. decoding) is supported.
214
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215@code{E} means that support is provided through an external library.
216
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217@section Video Codecs
218
219@multitable @columnfractions .4 .1 .1 .4
b3de4544 220@item Name @tab Encoding @tab Decoding @tab Comments
d66d8b83 221@item 4X Video @tab @tab X
d698c5d3 222 @tab Used in certain computer games.
913c3e2c 223@item American Laser Games MM @tab @tab X
d698c5d3 224 @tab Used in games like Mad Dog McCree.
d66d8b83 225@item AMV @tab @tab X
d698c5d3 226 @tab Used in Chinese MP3 players.
d66d8b83 227@item Apple Animation @tab X @tab X
d698c5d3 228 @tab fourcc: 'rle '
d66d8b83 229@item Apple Graphics @tab @tab X
d698c5d3 230 @tab fourcc: 'smc '
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231@item Apple MJPEG-B @tab @tab X
232@item Apple QuickDraw @tab @tab X
d698c5d3 233 @tab fourcc: qdrw
d66d8b83 234@item Apple Video @tab @tab X
d698c5d3 235 @tab fourcc: rpza
d66d8b83 236@item Asus v1 @tab X @tab X
d698c5d3 237 @tab fourcc: ASV1
d66d8b83 238@item Asus v2 @tab X @tab X
d698c5d3 239 @tab fourcc: ASV2
d66d8b83 240@item ATI VCR1 @tab @tab X
d698c5d3 241 @tab fourcc: VCR1
d66d8b83 242@item ATI VCR2 @tab @tab X
d698c5d3 243 @tab fourcc: VCR2
d66d8b83 244@item Autodesk RLE @tab @tab X
d698c5d3 245 @tab fourcc: AASC
d66d8b83 246@item AVID DNxHD @tab X @tab X
d698c5d3 247 @tab aka SMPTE VC3
bac4c85c 248@item AVS video @tab @tab X
d698c5d3 249 @tab Video encoding used by the Creature Shock game.
d66d8b83 250@item Bethsoft VID @tab @tab X
d698c5d3 251 @tab Used in some games from Bethesda Softworks.
bac4c85c 252@item C93 video @tab @tab X
d698c5d3 253 @tab Codec used in Cyberia game.
d66d8b83 254@item CamStudio @tab @tab X
d698c5d3 255 @tab fourcc: CSCD
bac4c85c 256@item Cin video @tab @tab X
d698c5d3 257 @tab Codec used in Delphine Software games.
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258@item Cinepak @tab @tab X
259@item Cirrus Logic AccuPak @tab @tab X
d698c5d3 260 @tab fourcc: CLJR
d66d8b83 261@item Creative YUV @tab @tab X
d698c5d3 262 @tab fourcc: CYUV
82ced5a9 263@item Dirac @tab E @tab E
360f980b 264 @tab supported through external libdirac/libschroedinger libraries
d66d8b83 265@item Duck TrueMotion v1 @tab @tab X
d698c5d3 266 @tab fourcc: DUCK
d66d8b83 267@item Duck TrueMotion v2 @tab @tab X
d698c5d3 268 @tab fourcc: TM20
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269@item DV @tab X @tab X
270@item DXA Video @tab @tab X
d698c5d3 271 @tab Codec originally used in Feeble Files game.
d66d8b83 272@item Electronic Arts CMV @tab @tab X
d698c5d3 273 @tab Used in NHL 95 game.
cfc78718 274@item Electronic Arts TGV @tab @tab X
42b30357 275@item Electronic Arts TGQ @tab @tab X
d8964f3a 276@item Electronic Arts TQI @tab @tab X
d66d8b83 277@item FFmpeg Video 1 @tab X @tab X
d698c5d3 278 @tab experimental lossless codec (fourcc: FFV1)
d66d8b83 279@item Flash Screen Video @tab X @tab X
d698c5d3 280 @tab fourcc: FSV1
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281@item FLIC video @tab @tab X
282@item FLV @tab X @tab X
d698c5d3 283 @tab Sorenson H.263 used in Flash
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284@item Fraps FPS1 @tab @tab X
285@item H.261 @tab X @tab X
286@item H.263(+) @tab X @tab X
d698c5d3 287 @tab also known as RealVideo 1.0
82ced5a9 288@item H.264 @tab E @tab X
360f980b 289 @tab encoding supported through external library libx264
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290@item HuffYUV @tab X @tab X
291@item IBM Ultimotion @tab @tab X
d698c5d3 292 @tab fourcc: ULTI
bac4c85c 293@item id Cinematic video @tab @tab X
d698c5d3 294 @tab Used in Quake II.
d66d8b83 295@item id RoQ @tab X @tab X
d698c5d3 296 @tab Used in Quake III, Jedi Knight 2, other computer games.
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297@item Intel Indeo 3 @tab @tab X
298@item Interplay Video @tab @tab X
d698c5d3 299 @tab Used in Interplay .MVE files.
d66d8b83 300@item JPEG-LS @tab X @tab X
d698c5d3 301 @tab fourcc: MJLS, lossless and near-lossless is supported.
d66d8b83 302@item KMVC @tab @tab X
d698c5d3 303 @tab Codec used in Worms games.
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304@item LOCO @tab @tab X
305@item lossless MJPEG @tab X @tab X
306@item Microsoft RLE @tab @tab X
307@item Microsoft Video-1 @tab @tab X
308@item Mimic @tab @tab X
d698c5d3 309 @tab Used in MSN Messenger Webcam streams.
d66d8b83 310@item Miro VideoXL @tab @tab X
d698c5d3 311 @tab fourcc: VIXL
d66d8b83 312@item MJPEG @tab X @tab X
822cc8f7 313@item Motion Pixels Video @tab @tab X
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314@item MPEG-1 @tab X @tab X
315@item MPEG-2 @tab X @tab X
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316@item MPEG-4 @tab X @tab X
317@item MSMPEG4 V1 @tab X @tab X
318@item MSMPEG4 V2 @tab X @tab X
319@item MSMPEG4 V3 @tab X @tab X
d66d8b83 320@item MSZH @tab @tab X
d698c5d3 321 @tab Part of LCL
d66d8b83 322@item On2 VP3 @tab @tab X
d698c5d3 323 @tab still experimental
d66d8b83 324@item On2 VP5 @tab @tab X
d698c5d3 325 @tab fourcc: VP50
d66d8b83 326@item On2 VP6 @tab @tab X
d698c5d3 327 @tab fourcc: VP60,VP61,VP62
d66d8b83 328@item planar RGB @tab @tab X
d698c5d3 329 @tab fourcc: 8BPS
d66d8b83 330@item QPEG @tab @tab X
d698c5d3 331 @tab fourccs: QPEG, Q1.0, Q1.1
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332@item RealVideo 1.0 @tab X @tab X
333@item RealVideo 2.0 @tab X @tab X
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334@item RealVideo 3.0 @tab @tab X
335 @tab still far from ideal
11c0f9ec 336@item RealVideo 4.0 @tab @tab X
d66d8b83 337@item Renderware TXD @tab @tab X
d698c5d3 338 @tab Texture dictionaries used by the Renderware Engine.
d66d8b83 339@item RTjpeg @tab @tab X
d698c5d3 340 @tab Video encoding used in NuppelVideo files.
bac4c85c 341@item Smacker video @tab @tab X
d698c5d3 342 @tab Video encoding used in Smacker.
d66d8b83 343@item Snow @tab X @tab X
d698c5d3 344 @tab experimental wavelet codec (fourcc: SNOW)
831ec935 345@item Sony PlayStation MDEC @tab @tab X
d66d8b83 346@item Sorenson Video 1 @tab X @tab X
d698c5d3 347 @tab fourcc: SVQ1
d66d8b83 348@item Sorenson Video 3 @tab @tab X
d698c5d3 349 @tab fourcc: SVQ3
d66d8b83 350@item Sunplus MJPEG @tab @tab X
d698c5d3 351 @tab fourcc: SP5X
d66d8b83 352@item TechSmith Camtasia @tab @tab X
d698c5d3 353 @tab fourcc: TSCC
82ced5a9 354@item Theora @tab E @tab X
360f980b 355 @tab encoding supported through external library libtheora
d66d8b83 356@item THP @tab @tab X
d698c5d3 357 @tab Used on the Nintendo GameCube.
bac4c85c 358@item Tiertex Seq video @tab @tab X
d698c5d3 359 @tab Codec used in DOS CD-ROM FlashBack game.
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360@item VC-1 @tab @tab X
361@item VMD Video @tab @tab X
d698c5d3 362 @tab Used in Sierra VMD files.
d66d8b83 363@item VMware Video @tab @tab X
d698c5d3 364 @tab Codec used in videos captured by VMware.
d0e1cd3d 365@item Westwood VQA @tab @tab X
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366@item Winnov WNV1 @tab @tab X
367@item WMV7 @tab X @tab X
368@item WMV8 @tab X @tab X
369@item WMV9 @tab @tab X
d698c5d3 370 @tab not completely working
d66d8b83 371@item Xan/WC3 @tab @tab X
d698c5d3 372 @tab Used in Wing Commander III .MVE files.
39271be4 373@item YAMAHA SMAF @tab X @tab X
d66d8b83 374@item ZLIB @tab X @tab X
d698c5d3 375 @tab part of LCL, encoder experimental
d66d8b83 376@item ZMBV @tab X @tab X
d698c5d3 377 @tab Encoder works only in PAL8.
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378@end multitable
379
380@code{X} means that encoding (resp. decoding) is supported.
381
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382@code{E} means that support is provided through an external library.
383
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384@section Audio Codecs
385
485ec4f1 386@multitable @columnfractions .4 .1 .1 .4
b3de4544 387@item Name @tab Encoding @tab Decoding @tab Comments
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388@item 4X IMA ADPCM @tab @tab X
389@item 8SVX audio @tab @tab X
82ced5a9 390@item AAC @tab E @tab X
360f980b 391 @tab encoding supported through external library libfaac
16d81b27 392@item AC-3 @tab IX @tab IX
82ced5a9 393@item AMR-NB @tab E @tab E
360f980b 394 @tab supported through external library libamrnb
82ced5a9 395@item AMR-WB @tab E @tab E
360f980b 396 @tab supported through external library libamrwb
16d81b27 397@item AMV IMA ADPCM @tab @tab X
d698c5d3 398 @tab Used in AMV files
833e90dd 399@item Apple lossless audio @tab X @tab X
d698c5d3 400 @tab QuickTime fourcc 'alac'
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401@item Apple MACE 3 @tab @tab X
402@item Apple MACE 6 @tab @tab X
403@item ATRAC 3 @tab @tab X
404@item CD-ROM XA ADPCM @tab @tab X
bac4c85c 405@item Cin audio @tab @tab X
d698c5d3 406 @tab Codec used in Delphine Software International games.
16d81b27 407@item Creative ADPCM @tab @tab X
d698c5d3 408 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
16d81b27 409@item CRI ADX ADPCM @tab X @tab X
d698c5d3 410 @tab Used in Sega Dreamcast games.
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411@item DSP Group TrueSpeech @tab @tab X
412@item DTS Coherent Audio @tab @tab X
413@item Duck DK3 IMA ADPCM @tab @tab X
d698c5d3 414 @tab Used in some Sega Saturn console games.
16d81b27 415@item Duck DK4 IMA ADPCM @tab @tab X
d698c5d3 416 @tab Used in some Sega Saturn console games.
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417@item DV audio @tab @tab X
418@item Electronic Arts ADPCM @tab @tab X
d698c5d3 419 @tab Used in various EA titles.
44723c84 420@item Enhanced AC-3 @tab @tab X
9a584db4 421@item FLAC lossless audio @tab IX @tab X
16d81b27 422@item G.726 ADPCM @tab X @tab X
82ced5a9 423@item GSM @tab E @tab E
3f33271a 424 @tab supported through external library libgsm
82ced5a9 425@item GSM_MS @tab E @tab E
3f33271a 426 @tab supported through external library libgsm
16d81b27 427@item id RoQ DPCM @tab X @tab X
d698c5d3 428 @tab Used in Quake III, Jedi Knight 2, other computer games.
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429@item Intel Music Coder @tab @tab X
430@item Interplay MVE DPCM @tab @tab X
d698c5d3 431 @tab Used in various Interplay computer games.
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432@item ISS IMA ADPCM @tab @tab X
433 @tab Used in FunCom games.
16d81b27 434@item MAXIS EA ADPCM @tab @tab X
d698c5d3 435 @tab Used in Sim City 3000.
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436@item Microsoft ADPCM @tab X @tab X
437@item MLP/TrueHD @tab @tab X
d698c5d3 438 @tab Used in DVD-Audio and Blu-Ray discs.
16d81b27 439@item Monkey's Audio @tab @tab X
d698c5d3 440 @tab Only versions 3.97-3.99 are supported.
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441@item MPEG audio layer 3 @tab E @tab IX
442 @tab encoding supported through external library LAME
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443@item MPEG audio layer 2 @tab IX @tab IX
444@item MS IMA ADPCM @tab X @tab X
445@item Musepack @tab @tab X
d698c5d3 446 @tab SV7 and SV8 are supported.
755ba886 447@item Nellymoser ASAO @tab X @tab X
73b458e3 448@item QCELP / PureVoice @tab @tab X
16d81b27 449@item Qdesign QDM2 @tab @tab X
d698c5d3 450 @tab There are still some distortions.
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451@item QT IMA ADPCM @tab X @tab X
452@item RA144 @tab @tab X
d698c5d3 453 @tab Real 14400 bit/s codec
16d81b27 454@item RA288 @tab @tab X
d698c5d3 455 @tab Real 28800 bit/s codec
575a5bf2 456@item RADnet @tab IX @tab IX
a692130f 457 @tab Real low bitrate AC-3 codec
16d81b27 458@item Real COOK @tab @tab X
d698c5d3 459 @tab All versions except 5.1 are supported.
bac4c85c 460@item Shorten @tab @tab X
16d81b27 461@item Sierra Online DPCM @tab @tab X
d698c5d3 462 @tab Used in Sierra Online game audio files.
bac4c85c 463@item Smacker audio @tab @tab X
16d81b27 464@item SMJPEG IMA ADPCM @tab @tab X
d698c5d3 465 @tab Used in certain Loki game ports.
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466@item Sonic @tab X @tab X
467 @tab experimental codec
468@item Sonic lossless @tab X @tab X
469 @tab experimental codec
82ced5a9 470@item Speex @tab @tab E
360f980b 471 @tab supported through external library libspeex
16d81b27 472@item THP ADPCM @tab @tab X
d698c5d3 473 @tab Used on the Nintendo GameCube.
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474@item True Audio (TTA) @tab @tab X
475@item Vorbis @tab X @tab X
bac4c85c 476@item WavPack @tab @tab X
16d81b27 477@item Westwood Studios IMA ADPCM @tab @tab X
d698c5d3 478 @tab Used in Westwood Studios games like Command and Conquer.
bac4c85c 479@item WMA v1/v2 @tab X @tab X
16d81b27 480@item Xan DPCM @tab @tab X
d698c5d3 481 @tab Used in Origin's Wing Commander IV AVI files.
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482@end multitable
483
484@code{X} means that encoding (resp. decoding) is supported.
485
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486@code{E} means that support is provided through an external library.
487
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488@code{I} means that an integer-only version is available, too (ensures high
489performance on systems without hardware floating point support).
490
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491@section Subtitle Formats
492
485ec4f1 493@multitable @columnfractions .4 .1 .1 .1 .1 .1
9afc2917 494@item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding
913c3e2c 495@item SSA/ASS @tab X @tab X
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496@item DVB @tab X @tab X @tab X @tab X
497@item DVD @tab X @tab X @tab X @tab X
498@item XSUB @tab @tab @tab @tab X
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499@end multitable
500
501@code{X} means that the feature is supported.
502
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503@chapter Platform Specific information
504
505@section BSD
506
507BSD make will not build FFmpeg, you need to install and use GNU Make
508(@file{gmake}).
509
510@section Windows
511
46a845d0 512To get help and instructions for building FFmpeg under Windows, check out
d0e1cd3d 513the FFmpeg Windows Help Forum at
ab5ce4ae 514@url{http://ffmpeg.arrozcru.org/}.
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515
516@subsection Native Windows compilation
517
c1989552 518FFmpeg can be built to run natively on Windows using the MinGW tools. Install
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519the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
520You can find detailed installation
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521instructions in the download section and the FAQ.
522
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523FFmpeg does not build out-of-the-box with the packages the automated MinGW
524installer provides. It also requires coreutils to be installed and many other
525packages updated to the latest version. The minimum version for some packages
526are listed below:
527
528@itemize
529@item bash 3.1
530@item msys-make 3.81-2 (note: not mingw32-make)
2014b51c 531@item w32api 3.13
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532@item mingw-runtime 3.15
533@end itemize
534
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535You will also need to pass @code{-fno-common} to the compiler to work around
536a GCC bug (see @url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216}).
537
c1989552 538Within the MSYS shell, configure and make with:
d0e1cd3d 539
c1989552 540@example
0f898714 541./configure --enable-memalign-hack --extra-cflags=-fno-common
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542make
543make install
544@end example
d0e1cd3d 545
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546This will install @file{ffmpeg.exe} along with many other development files
547to @file{/usr/local}. You may specify another install path using the
548@code{--prefix} option in @file{configure}.
d0e1cd3d 549
c1989552 550Notes:
d0e1cd3d 551
c1989552 552@itemize
d0e1cd3d 553
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554@item In order to compile vhooks, you must have a POSIX-compliant libdl in
555your MinGW system. Get dlfcn-win32 from
556@url{http://code.google.com/p/dlfcn-win32}.
d0e1cd3d 557
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558@item In order to compile FFplay, you must have the MinGW development library
559of SDL. Get it from @url{http://www.libsdl.org}.
560Edit the @file{bin/sdl-config} script so that it points to the correct prefix
561where SDL was installed. Verify that @file{sdl-config} can be launched from
562the MSYS command line.
d0e1cd3d 563
d0e1cd3d 564@item By using @code{./configure --enable-shared} when configuring FFmpeg,
c1989552 565you can build libavutil, libavcodec and libavformat as DLLs.
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566
567@end itemize
568
c1989552 569@subsection Microsoft Visual C++ compatibility
d0e1cd3d 570
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571As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
572want to use the libav* libraries in your own applications, you can still
573compile those applications using MSVC++. But the libav* libraries you link
574to @emph{must} be built with MinGW. However, you will not be able to debug
575inside the libav* libraries, since MSVC++ does not recognize the debug
576symbols generated by GCC.
577We strongly recommend you to move over from MSVC++ to MinGW tools.
d0e1cd3d 578
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579This description of how to use the FFmpeg libraries with MSVC++ is based on
580Microsoft Visual C++ 2005 Express Edition. If you have a different version,
581you might have to modify the procedures slightly.
d0e1cd3d 582
c1989552 583@subsubsection Using static libraries
d0e1cd3d 584
c1989552 585Assuming you have just built and installed FFmpeg in @file{/usr/local}.
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586
587@enumerate
588
589@item Create a new console application ("File / New / Project") and then
590select "Win32 Console Application". On the appropriate page of the
591Application Wizard, uncheck the "Precompiled headers" option.
592
593@item Write the source code for your application, or, for testing, just
594copy the code from an existing sample application into the source file
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595that MSVC++ has already created for you. For example, you can copy
596@file{output_example.c} from the FFmpeg distribution.
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597
598@item Open the "Project / Properties" dialog box. In the "Configuration"
599combo box, select "All Configurations" so that the changes you make will
600affect both debug and release builds. In the tree view on the left hand
601side, select "C/C++ / General", then edit the "Additional Include
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602Directories" setting to contain the path where the FFmpeg includes were
603installed (i.e. @file{c:\msys\1.0\local\include}).
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604Do not add MinGW's include directory here, or the include files will
605conflict with MSVC's.
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606
607@item Still in the "Project / Properties" dialog box, select
608"Linker / General" from the tree view and edit the
609"Additional Library Directories" setting to contain the @file{lib}
610directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
611the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
612and the directory where MinGW's GCC libs are installed
613(i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
614"Linker / Input" from the tree view, and add the files @file{libavformat.a},
615@file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
616@file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
617to the end of "Additional Dependencies".
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618
619@item Now, select "C/C++ / Code Generation" from the tree view. Select
620"Debug" in the "Configuration" combo box. Make sure that "Runtime
621Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
622the "Configuration" combo box and make sure that "Runtime Library" is
623set to "Multi-threaded DLL".
624
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625@item Click "OK" to close the "Project / Properties" dialog box.
626
627@item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
628Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
629and install it in MSVC++'s include directory
630(i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
631
632@item MSVC++ also does not understand the @code{inline} keyword used by
633FFmpeg, so you must add this line before @code{#include}ing libav*:
634@example
635#define inline _inline
636@end example
637
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638@item Build your application, everything should work.
639
640@end enumerate
641
642@subsubsection Using shared libraries
643
644This is how to create DLL and LIB files that are compatible with MSVC++:
645
646@enumerate
647
648@item Add a call to @file{vcvars32.bat} (which sets up the environment
649variables for the Visual C++ tools) as the first line of @file{msys.bat}.
650The standard location for @file{vcvars32.bat} is
651@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
652and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
653If this corresponds to your setup, add the following line as the first line
654of @file{msys.bat}:
655
656@example
657call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
658@end example
659
660Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
661and run @file{c:\msys\1.0\msys.bat} from there.
662
663@item Within the MSYS shell, run @code{lib.exe}. If you get a help message
664from @file{Microsoft (R) Library Manager}, this means your environment
665variables are set up correctly, the @file{Microsoft (R) Library Manager}
666is on the path and will be used by FFmpeg to create
667MSVC++-compatible import libraries.
668
669@item Build FFmpeg with
670
671@example
672./configure --enable-shared --enable-memalign-hack
673make
674make install
675@end example
676
677Your install path (@file{/usr/local/} by default) should now have the
678necessary DLL and LIB files under the @file{bin} directory.
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679
680@end enumerate
681
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682To use those files with MSVC++, do the same as you would do with
683the static libraries, as described above. But in Step 4,
684you should only need to add the directory where the LIB files are installed
685(i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
686installed in the @file{bin} directory. And instead of adding @file{libxx.a}
687files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
688@file{avutil.lib}. There should be no need for @file{libmingwex.a},
689@file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
690statically linked into the DLLs. The @file{bin} directory contains a bunch
691of DLL files, but the ones that are actually used to run your application
692are the ones with a major version number in their filenames
693(i.e. @file{avcodec-51.dll}).
694
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695@subsection Cross compilation for Windows with Linux
696
697You must use the MinGW cross compilation tools available at
698@url{http://www.mingw.org/}.
699
700Then configure FFmpeg with the following options:
701@example
702./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
703@end example
704(you can change the cross-prefix according to the prefix chosen for the
705MinGW tools).
706
707Then you can easily test FFmpeg with Wine
708(@url{http://www.winehq.com/}).
709
710@subsection Compilation under Cygwin
711
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712The main issue with the 1.5.x Cygwin versions is that newlib, its C library,
713does not contain llrint(). You need to upgrade to the unstable 1.7.x versions,
714or leverage the implementation in MinGW (as explained below).
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715
716Just install your Cygwin with all the "Base" packages, plus the
717following "Devel" ones:
718@example
f496ab12 719binutils, gcc-core, make, subversion, mingw-runtime, diffutils
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720@end example
721
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722The experimental gcc4 package is still buggy, hence please
723use the official gcc 3.4.4 or a 4.2.x compiled from source by yourself.
724
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725Install the current binutils-20080624-2 as they work fine (the old
726binutils-20060709-1 proved buggy on shared builds).
d0e1cd3d 727
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728Then create a small library that just contains llrint():
729
730@example
731ar x /usr/lib/mingw/libmingwex.a llrint.o
732ar cq /usr/local/lib/libllrint.a llrint.o
733@end example
734
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735Then run
736
737@example
29c3d42b 738./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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739@end example
740
741to make a static build or
742
743@example
29c3d42b 744./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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745@end example
746
747to build shared libraries.
748
749If you want to build FFmpeg with additional libraries, download Cygwin
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750"Devel" packages for Ogg and Vorbis from any Cygwin packages repository:
751@example
752libogg-devel, libvorbis-devel
753@end example
754
755These library packages are only available from Cygwin Ports
be8497b0 756(@url{http://sourceware.org/cygwinports/}) :
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757
758@example
759yasm, libSDL-devel, libdirac-devel, libfaac-devel, libfaad-devel, libgsm-devel,
760libmp3lame-devel, libschroedinger1.0-devel, speex-devel, libtheora-devel,
761libxvidcore-devel
762@end example
763
764The recommendation for libnut and x264 is to build them from source by
765yourself, as they evolve too quickly for Cygwin Ports to be up to date.
d0e1cd3d 766
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767Cygwin 1.7.x has IPv6 support. You can add IPv6 to Cygwin 1.5.x by means
768of the @code{libgetaddrinfo-devel} package, available at Cygwin Ports.
769
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770@subsection Crosscompilation for Windows under Cygwin
771
772With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
773
774Just install your Cygwin as explained before, plus these additional
775"Devel" packages:
776@example
777gcc-mingw-core, mingw-runtime, mingw-zlib
778@end example
779
780and add some special flags to your configure invocation.
781
782For a static build run
783@example
784./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
785@end example
786
787and for a build with shared libraries
788@example
789./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
790@end example
791
792@section BeOS
793
5f757b85 794BeOS support is broken in mysterious ways.
d0e1cd3d 795
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796@section OS/2
797
798For information about compiling FFmpeg on OS/2 see
799@url{http://www.edm2.com/index.php/FFmpeg}.
800
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801@chapter Developers Guide
802
803@section API
804@itemize @bullet
805@item libavcodec is the library containing the codecs (both encoding and
806decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
807
808@item libavformat is the library containing the file format handling (mux and
809demux code for several formats). Look at @file{ffplay.c} to use it in a
810player. See @file{output_example.c} to use it to generate audio or video
811streams.
812
813@end itemize
814
815@section Integrating libavcodec or libavformat in your program
816
817You can integrate all the source code of the libraries to link them
818statically to avoid any version problem. All you need is to provide a
819'config.mak' and a 'config.h' in the parent directory. See the defines
820generated by ./configure to understand what is needed.
821
822You can use libavcodec or libavformat in your commercial program, but
823@emph{any patch you make must be published}. The best way to proceed is
824to send your patches to the FFmpeg mailing list.
825
826@node Coding Rules
827@section Coding Rules
828
829FFmpeg is programmed in the ISO C90 language with a few additional
830features from ISO C99, namely:
831@itemize @bullet
832@item
833the @samp{inline} keyword;
834@item
835@samp{//} comments;
836@item
837designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
838@item
839compound literals (@samp{x = (struct s) @{ 17, 23 @};})
840@end itemize
841
842These features are supported by all compilers we care about, so we will not
843accept patches to remove their use unless they absolutely do not impair
844clarity and performance.
845
846All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
847compiles with several other compilers, such as the Compaq ccc compiler
848or Sun Studio 9, and we would like to keep it that way unless it would
849be exceedingly involved. To ensure compatibility, please do not use any
850additional C99 features or GCC extensions. Especially watch out for:
851@itemize @bullet
852@item
853mixing statements and declarations;
854@item
855@samp{long long} (use @samp{int64_t} instead);
856@item
857@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
858@item
859GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
860@end itemize
861
862Indent size is 4.
863The presentation is the one specified by 'indent -i4 -kr -nut'.
864The TAB character is forbidden outside of Makefiles as is any
865form of trailing whitespace. Commits containing either will be
866rejected by the Subversion repository.
867
868The main priority in FFmpeg is simplicity and small code size in order to
869minimize the bug count.
870
871Comments: Use the JavaDoc/Doxygen
872format (see examples below) so that code documentation
873can be generated automatically. All nontrivial functions should have a comment
874above them explaining what the function does, even if it is just one sentence.
875All structures and their member variables should be documented, too.
876@example
877/**
878 * @@file mpeg.c
879 * MPEG codec.
880 * @@author ...
881 */
882
883/**
884 * Summary sentence.
885 * more text ...
886 * ...
887 */
888typedef struct Foobar@{
889 int var1; /**< var1 description */
890 int var2; ///< var2 description
891 /** var3 description */
892 int var3;
893@} Foobar;
894
895/**
896 * Summary sentence.
897 * more text ...
898 * ...
899 * @@param my_parameter description of my_parameter
900 * @@return return value description
901 */
902int myfunc(int my_parameter)
903...
904@end example
905
906fprintf and printf are forbidden in libavformat and libavcodec,
907please use av_log() instead.
908
909Casts should be used only when necessary. Unneeded parentheses
910should also be avoided if they don't make the code easier to understand.
911
912@section Development Policy
913
914@enumerate
915@item
916 Contributions should be licensed under the LGPL 2.1, including an
917 "or any later version" clause, or the MIT license. GPL 2 including
918 an "or any later version" clause is also acceptable, but LGPL is
919 preferred.
920@item
921 You must not commit code which breaks FFmpeg! (Meaning unfinished but
922 enabled code which breaks compilation or compiles but does not work or
923 breaks the regression tests)
924 You can commit unfinished stuff (for testing etc), but it must be disabled
925 (#ifdef etc) by default so it does not interfere with other developers'
926 work.
927@item
928 You do not have to over-test things. If it works for you, and you think it
929 should work for others, then commit. If your code has problems
930 (portability, triggers compiler bugs, unusual environment etc) they will be
931 reported and eventually fixed.
932@item
933 Do not commit unrelated changes together, split them into self-contained
934 pieces. Also do not forget that if part B depends on part A, but A does not
935 depend on B, then A can and should be committed first and separate from B.
936 Keeping changes well split into self-contained parts makes reviewing and
937 understanding them on the commit log mailing list easier. This also helps
938 in case of debugging later on.
939 Also if you have doubts about splitting or not splitting, do not hesitate to
940 ask/discuss it on the developer mailing list.
941@item
942 Do not change behavior of the program (renaming options etc) without
943 first discussing it on the ffmpeg-devel mailing list. Do not remove
944 functionality from the code. Just improve!
945
946 Note: Redundant code can be removed.
947@item
948 Do not commit changes to the build system (Makefiles, configure script)
949 which change behavior, defaults etc, without asking first. The same
950 applies to compiler warning fixes, trivial looking fixes and to code
951 maintained by other developers. We usually have a reason for doing things
952 the way we do. Send your changes as patches to the ffmpeg-devel mailing
953 list, and if the code maintainers say OK, you may commit. This does not
954 apply to files you wrote and/or maintain.
955@item
956 We refuse source indentation and other cosmetic changes if they are mixed
957 with functional changes, such commits will be rejected and removed. Every
958 developer has his own indentation style, you should not change it. Of course
959 if you (re)write something, you can use your own style, even though we would
960 prefer if the indentation throughout FFmpeg was consistent (Many projects
961 force a given indentation style - we do not.). If you really need to make
962 indentation changes (try to avoid this), separate them strictly from real
963 changes.
964
965 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
966 then either do NOT change the indentation of the inner part within (do not
967 move it to the right)! or do so in a separate commit
968@item
969 Always fill out the commit log message. Describe in a few lines what you
970 changed and why. You can refer to mailing list postings if you fix a
971 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
972@item
973 If you apply a patch by someone else, include the name and email address in
974 the log message. Since the ffmpeg-cvslog mailing list is publicly
975 archived you should add some SPAM protection to the email address. Send an
976 answer to ffmpeg-devel (or wherever you got the patch from) saying that
977 you applied the patch.
978@item
979 When applying patches that have been discussed (at length) on the mailing
980 list, reference the thread in the log message.
981@item
982 Do NOT commit to code actively maintained by others without permission.
983 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
984 timeframe (12h for build failures and security fixes, 3 days small changes,
985 1 week for big patches) then commit your patch if you think it is OK.
986 Also note, the maintainer can simply ask for more time to review!
987@item
988 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
989 are sent there and reviewed by all the other developers. Bugs and possible
990 improvements or general questions regarding commits are discussed there. We
991 expect you to react if problems with your code are uncovered.
992@item
993 Update the documentation if you change behavior or add features. If you are
994 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
995 maintainer(s) will review and commit your stuff.
996@item
997 Try to keep important discussions and requests (also) on the public
998 developer mailing list, so that all developers can benefit from them.
999@item
1000 Never write to unallocated memory, never write over the end of arrays,
1001 always check values read from some untrusted source before using them
1002 as array index or other risky things.
1003@item
1004 Remember to check if you need to bump versions for the specific libav
1005 parts (libavutil, libavcodec, libavformat) you are changing. You need
b98052d5 1006 to change the version integer.
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1007 Incrementing the first component means no backward compatibility to
1008 previous versions (e.g. removal of a function from the public API).
1009 Incrementing the second component means backward compatible change
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1010 (e.g. addition of a function to the public API or extension of an
1011 existing data structure).
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1012 Incrementing the third component means a noteworthy binary compatible
1013 change (e.g. encoder bug fix that matters for the decoder).
1014@item
53407b64 1015 Compiler warnings indicate potential bugs or code with bad style. If a type of
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1016 warning always points to correct and clean code, that warning should
1017 be disabled, not the code changed.
1018 Thus the remaining warnings can either be bugs or correct code.
beaa4a91 1019 If it is a bug, the bug has to be fixed. If it is not, the code should
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1020 be changed to not generate a warning unless that causes a slowdown
1021 or obfuscates the code.
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1022@item
1023 If you add a new file, give it a proper license header. Do not copy and
1024 paste it from a random place, use an existing file as template.
1025@end enumerate
1026
1027We think our rules are not too hard. If you have comments, contact us.
1028
1029Note, these rules are mostly borrowed from the MPlayer project.
1030
1031@section Submitting patches
1032
1033First, (@pxref{Coding Rules}) above if you did not yet.
1034
1035When you submit your patch, try to send a unified diff (diff '-up'
1036option). We cannot read other diffs :-)
1037
1038Also please do not submit a patch which contains several unrelated changes.
1039Split it into separate, self-contained pieces. This does not mean splitting
1040file by file. Instead, make the patch as small as possible while still
1041keeping it as a logical unit that contains an individual change, even
1042if it spans multiple files. This makes reviewing your patches much easier
1043for us and greatly increases your chances of getting your patch applied.
1044
1045Run the regression tests before submitting a patch so that you can
1046verify that there are no big problems.
1047
1048Patches should be posted as base64 encoded attachments (or any other
1049encoding which ensures that the patch will not be trashed during
1050transmission) to the ffmpeg-devel mailing list, see
1051@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1052
1053It also helps quite a bit if you tell us what the patch does (for example
1054'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1055and has no lrint()')
1056
1057Also please if you send several patches, send each patch as a separate mail,
1058do not attach several unrelated patches to the same mail.
1059
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1060@section New codecs or formats checklist
1061
1062@enumerate
1063@item
1064 Did you use av_cold for codec initialization and close functions?
1065@item
1066 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
1067 AVInputFormat/AVOutputFormat struct?
1068@item
1069 Did you bump the minor version number in @file{avcodec.h} or
1070 @file{avformat.h}?
1071@item
1072 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
1073@item
1074 Did you add the CodecID to @file{avcodec.h}?
1075@item
1076 If it has a fourcc, did you add it to @file{libavformat/riff.c},
1077 even if it is only a decoder?
1078@item
1079 Did you add a rule to compile the appropriate files in the Makefile?
1080 Remember to do this even if you're just adding a format to a file that is
1081 already being compiled by some other rule, like a raw demuxer.
1082@item
1083 Did you add an entry to the table of supported formats or codecs in the
1084 documentation?
1085@item
1086 Did you add an entry in the Changelog?
1087@item
1088 If it depends on a parser or a library, did you add that dependency in
1089 configure?
1090@item
1091 Did you "svn add" the appropriate files before commiting?
1092@end enumerate
1093
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1094@section patch submission checklist
1095
1096@enumerate
1097@item
1098 Do the regression tests pass with the patch applied?
1099@item
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1100 Does @code{make checkheaders} pass with the patch applied?
1101@item
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1102 Is the patch a unified diff?
1103@item
1104 Is the patch against latest FFmpeg SVN?
1105@item
1106 Are you subscribed to ffmpeg-dev?
1107 (the list is subscribers only due to spam)
1108@item
1109 Have you checked that the changes are minimal, so that the same cannot be
1110 achieved with a smaller patch and/or simpler final code?
1111@item
1112 If the change is to speed critical code, did you benchmark it?
1113@item
1114 If you did any benchmarks, did you provide them in the mail?
1115@item
1116 Have you checked that the patch does not introduce buffer overflows or
1117 other security issues?
1118@item
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1119 Did you test your decoder or demuxer against damaged data? If no, see
1120 tools/trasher and the noise bitstream filter. Your decoder or demuxer
1121 should not crash or end in a (near) infinite loop when fed damaged data.
b885e0db 1122@item
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1123 Is the patch created from the root of the source tree, so it can be
1124 applied with @code{patch -p0}?
1125@item
1126 Does the patch not mix functional and cosmetic changes?
1127@item
1128 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1129@item
1130 Is the patch attached to the email you send?
1131@item
1132 Is the mime type of the patch correct? It should be text/x-diff or
1133 text/x-patch or at least text/plain and not application/octet-stream.
1134@item
1135 If the patch fixes a bug, did you provide a verbose analysis of the bug?
1136@item
1137 If the patch fixes a bug, did you provide enough information, including
1138 a sample, so the bug can be reproduced and the fix can be verified?
1139 Note please do not attach samples >100k to mails but rather provide a
0fa5f24c 1140 URL, you can upload to ftp://upload.ffmpeg.org
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1141@item
1142 Did you provide a verbose summary about what the patch does change?
1143@item
1144 Did you provide a verbose explanation why it changes things like it does?
1145@item
1146 Did you provide a verbose summary of the user visible advantages and
1147 disadvantages if the patch is applied?
1148@item
1149 Did you provide an example so we can verify the new feature added by the
1150 patch easily?
1151@item
1152 If you added a new file, did you insert a license header? It should be
1153 taken from FFmpeg, not randomly copied and pasted from somewhere else.
1154@item
1155 You should maintain alphabetical order in alphabetically ordered lists as
1156 long as doing so does not break API/ABI compatibility.
1157@item
1158 Lines with similar content should be aligned vertically when doing so
1159 improves readability.
1160@item
1161 Did you provide a suggestion for a clear commit log message?
1162@end enumerate
1163
1164@section Patch review process
1165
1166All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1167clear note that the patch is not for SVN.
1168Reviews and comments will be posted as replies to the patch on the
1169mailing list. The patch submitter then has to take care of every comment,
1170that can be by resubmitting a changed patch or by discussion. Resubmitted
1171patches will themselves be reviewed like any other patch. If at some point
1172a patch passes review with no comments then it is approved, that can for
1173simple and small patches happen immediately while large patches will generally
1174have to be changed and reviewed many times before they are approved.
1175After a patch is approved it will be committed to the repository.
1176
1177We will review all submitted patches, but sometimes we are quite busy so
1178especially for large patches this can take several weeks.
1179
1180When resubmitting patches, please do not make any significant changes
1181not related to the comments received during review. Such patches will
1182be rejected. Instead, submit significant changes or new features as
1183separate patches.
1184
1185@section Regression tests
1186
1187Before submitting a patch (or committing to the repository), you should at least
1188test that you did not break anything.
1189
1190The regression tests build a synthetic video stream and a synthetic
1191audio stream. These are then encoded and decoded with all codecs or
1192formats. The CRC (or MD5) of each generated file is recorded in a
1193result file. A 'diff' is launched to compare the reference results and
1194the result file.
1195
1196The regression tests then go on to test the FFserver code with a
1197limited set of streams. It is important that this step runs correctly
1198as well.
1199
1200Run 'make test' to test all the codecs and formats.
1201
1202Run 'make fulltest' to test all the codecs, formats and FFserver.
1203
1204[Of course, some patches may change the results of the regression tests. In
1205this case, the reference results of the regression tests shall be modified
1206accordingly].
1207
1208@bye