cosmetics: Slightly update MP3 support entry.
[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
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47@item American Laser Games MM @tab @tab X
48 @tab Multimedia format used in games like Mad Dog McCree.
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49@item ASF @tab X @tab X
50@item AVI @tab X @tab X
51@item AVM2 (Flash 9) @tab X @tab X
d698c5d3 52 @tab Only embedded audio is decoded.
c6b2dc34 53@item AVS @tab @tab X
d698c5d3 54 @tab Multimedia format used by the Creature Shock game.
c6b2dc34 55@item Bethsoft VID @tab @tab X
d698c5d3 56 @tab Used in some games from Bethesda Softworks.
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57@item BFI @tab @tab X
58 @tab Brute Force & Ignorance, used in Flash Traffic: City of Angels.
c6b2dc34 59@item C93 @tab @tab X
d698c5d3 60 @tab Used in the game Cyberia from Interplay.
c6b2dc34 61@item CIN @tab @tab X
d698c5d3 62 @tab Multimedia format used by Delphine Software games.
c6b2dc34 63@item Creative VOC @tab X @tab X
d698c5d3 64 @tab Created for the Sound Blaster Pro.
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65@item CRYO APC @tab @tab X
66 @tab Audio format used in some games by CRYO Interactive Entertainment.
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67@item DV @tab X @tab X
68@item DXA @tab @tab X
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69 @tab This format is used in the non-Windows version of the Feeble Files
70 game and different game cutscenes repacked for use with ScummVM.
c6b2dc34 71@item Electronic Arts Multimedia @tab @tab X
d698c5d3 72 @tab Used in various EA games; files have extensions like WVE and UV2.
c6b2dc34 73@item FLIC @tab @tab X
d698c5d3 74 @tab .fli/.flc files
c6b2dc34 75@item FLV @tab X @tab X
d698c5d3 76 @tab Macromedia Flash video files
c6b2dc34 77@item GXF @tab X @tab X
d698c5d3 78 @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley
64c2f20a 79 playout servers.
76ec3939 80@item id Cinematic @tab @tab X
d698c5d3 81 @tab Used in Quake II.
76ec3939 82@item id RoQ @tab X @tab X
d698c5d3 83 @tab Used in Quake III, Jedi Knight 2, other computer games.
c6b2dc34 84@item IFF @tab @tab X
d698c5d3 85 @tab Interchange File Format
c6b2dc34 86@item Interplay MVE @tab @tab X
d698c5d3 87 @tab Format used in various Interplay computer games.
c6b2dc34 88@item LMLM4 @tab @tab X
d698c5d3 89 @tab Used by Linux Media Labs MPEG-4 PCI boards
64c2f20a 90@item Matroska @tab X @tab X
c6b2dc34 91@item MAXIS EA XA @tab @tab X
d698c5d3 92 @tab Used in Sim City 3000; file extension .xa.
64c2f20a 93@item Monkey's Audio @tab @tab X
822cc8f7 94@item Motion Pixels MVI @tab @tab X
64c2f20a 95@item MOV/QuickTime @tab X @tab X
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96@item MPEG audio @tab X @tab X
97@item MPEG-1 systems @tab X @tab X
d698c5d3 98 @tab muxed audio and video
c6b2dc34 99@item MPEG-2 PS @tab X @tab X
d698c5d3 100 @tab also known as @code{VOB} file
c6b2dc34 101@item MPEG-2 TS @tab @tab X
d698c5d3 102 @tab also known as DVB Transport Stream
c6b2dc34 103@item MPEG-4 @tab X @tab X
d698c5d3 104 @tab MPEG-4 is a variant of QuickTime.
bac4c85c 105@item MSN TCP webcam @tab @tab X
d698c5d3 106 @tab Used by MSN Messenger webcam streams.
bb68b69d 107@item MXF @tab X @tab X
d698c5d3 108 @tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
64c2f20a 109@item Nullsoft Video @tab @tab X
c6b2dc34 110@item NUT @tab X @tab X
d698c5d3 111 @tab NUT Open Container Format
c6b2dc34 112@item OMA @tab @tab X
d698c5d3 113 @tab Audio format used in Sony Sonic Stage and Sony Vegas.
64c2f20a 114@item PlayStation STR @tab @tab X
c6b2dc34 115@item PVA @tab @tab X
d698c5d3 116 @tab Used by TechnoTrend DVB PCI boards.
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117@item raw AC-3 @tab X @tab X
118@item raw CRI ADX audio @tab X @tab X
119@item raw MJPEG @tab X @tab X
120@item raw MPEG video @tab X @tab X
121@item raw MPEG-4 video @tab X @tab X
eb6fc557 122@item raw PCM 8/16/32 bits, 32/64-bit floating point, mu-law/A-law @tab X @tab X
76ec3939 123@item raw Shorten audio @tab @tab X
64c2f20a 124@item RealMedia @tab X @tab X
c6b2dc34 125@item RL2 @tab @tab X
d698c5d3 126 @tab Audio and video format used in some games by Entertainment Software Partners.
c6b2dc34 127@item Sega FILM/CPK @tab @tab X
d698c5d3 128 @tab Used in many Sega Saturn console games.
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129@item SEQ @tab @tab X
130 @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
c6b2dc34 131@item Sierra Online @tab @tab X
d698c5d3 132 @tab .sol files used in Sierra Online games.
c6b2dc34 133@item Sierra VMD @tab @tab X
d698c5d3 134 @tab Used in Sierra CD-ROM games.
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135@item SIFF @tab @tab X
136 @tab Audio and video format used in some games by Beam Software.
c6b2dc34 137@item Smacker @tab @tab X
d698c5d3 138 @tab Multimedia format used by many games.
64c2f20a 139@item SUN AU format @tab X @tab X
c6b2dc34 140@item THP @tab @tab X
d698c5d3 141 @tab Used on the Nintendo GameCube.
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142@item WAV @tab X @tab X
143@item WC3 Movie @tab @tab X
d698c5d3 144 @tab Multimedia format used in Origin's Wing Commander III computer game.
c6b2dc34 145@item Westwood Studios VQA/AUD @tab @tab X
d698c5d3 146 @tab Multimedia formats used in Westwood Studios games.
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147@end multitable
148
149@code{X} means that encoding (resp. decoding) is supported.
150
151@section Image Formats
152
153FFmpeg can read and write images for each frame of a video sequence. The
154following image formats are supported:
155
156@multitable @columnfractions .4 .1 .1 .4
b3de4544 157@item Name @tab Encoding @tab Decoding @tab Comments
64c2f20a 158@item .Y.U.V @tab X @tab X @tab one raw file per component
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159@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
160@item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
d0e1cd3d 161@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
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162@item PCX @tab @tab X @tab PC Paintbrush
163@item PGM, PPM @tab X @tab X
d0e1cd3d 164@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
0a91f4ee 165@item PNG @tab X @tab X @tab 2/4 bpp not supported yet
d0e1cd3d 166@item PTX @tab @tab X @tab V.Flash PTX format
d1928ac1 167@item RAS @tab @tab X @tab Sun Rasterfile
3d172fb5 168@item SGI @tab X @tab X @tab SGI RGB image format
3d172fb5 169@item Targa @tab @tab X @tab Targa (.TGA) image format
64c2f20a 170@item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
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171@end multitable
172
173@code{X} means that encoding (resp. decoding) is supported.
174
175@section Video Codecs
176
177@multitable @columnfractions .4 .1 .1 .4
b3de4544 178@item Name @tab Encoding @tab Decoding @tab Comments
d66d8b83 179@item 4X Video @tab @tab X
d698c5d3 180 @tab Used in certain computer games.
d66d8b83 181@item American Laser Games Video @tab @tab X
d698c5d3 182 @tab Used in games like Mad Dog McCree.
d66d8b83 183@item AMV @tab @tab X
d698c5d3 184 @tab Used in Chinese MP3 players.
d66d8b83 185@item Apple Animation @tab X @tab X
d698c5d3 186 @tab fourcc: 'rle '
d66d8b83 187@item Apple Graphics @tab @tab X
d698c5d3 188 @tab fourcc: 'smc '
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189@item Apple MJPEG-B @tab @tab X
190@item Apple QuickDraw @tab @tab X
d698c5d3 191 @tab fourcc: qdrw
d66d8b83 192@item Apple Video @tab @tab X
d698c5d3 193 @tab fourcc: rpza
d66d8b83 194@item Asus v1 @tab X @tab X
d698c5d3 195 @tab fourcc: ASV1
d66d8b83 196@item Asus v2 @tab X @tab X
d698c5d3 197 @tab fourcc: ASV2
d66d8b83 198@item ATI VCR1 @tab @tab X
d698c5d3 199 @tab fourcc: VCR1
d66d8b83 200@item ATI VCR2 @tab @tab X
d698c5d3 201 @tab fourcc: VCR2
d66d8b83 202@item Autodesk RLE @tab @tab X
d698c5d3 203 @tab fourcc: AASC
d66d8b83 204@item AVID DNxHD @tab X @tab X
d698c5d3 205 @tab aka SMPTE VC3
bac4c85c 206@item AVS video @tab @tab X
d698c5d3 207 @tab Video encoding used by the Creature Shock game.
d66d8b83 208@item Bethsoft VID @tab @tab X
d698c5d3 209 @tab Used in some games from Bethesda Softworks.
bac4c85c 210@item C93 video @tab @tab X
d698c5d3 211 @tab Codec used in Cyberia game.
d66d8b83 212@item CamStudio @tab @tab X
d698c5d3 213 @tab fourcc: CSCD
bac4c85c 214@item Cin video @tab @tab X
d698c5d3 215 @tab Codec used in Delphine Software games.
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216@item Cinepak @tab @tab X
217@item Cirrus Logic AccuPak @tab @tab X
d698c5d3 218 @tab fourcc: CLJR
d66d8b83 219@item Creative YUV @tab @tab X
d698c5d3 220 @tab fourcc: CYUV
82ced5a9 221@item Dirac @tab E @tab E
360f980b 222 @tab supported through external libdirac/libschroedinger libraries
d66d8b83 223@item Duck TrueMotion v1 @tab @tab X
d698c5d3 224 @tab fourcc: DUCK
d66d8b83 225@item Duck TrueMotion v2 @tab @tab X
d698c5d3 226 @tab fourcc: TM20
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227@item DV @tab X @tab X
228@item DXA Video @tab @tab X
d698c5d3 229 @tab Codec originally used in Feeble Files game.
d66d8b83 230@item Electronic Arts CMV @tab @tab X
d698c5d3 231 @tab Used in NHL 95 game.
cfc78718 232@item Electronic Arts TGV @tab @tab X
d66d8b83 233@item FFmpeg Video 1 @tab X @tab X
d698c5d3 234 @tab experimental lossless codec (fourcc: FFV1)
d66d8b83 235@item Flash Screen Video @tab X @tab X
d698c5d3 236 @tab fourcc: FSV1
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237@item FLIC video @tab @tab X
238@item FLV @tab X @tab X
d698c5d3 239 @tab Sorenson H.263 used in Flash
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240@item Fraps FPS1 @tab @tab X
241@item H.261 @tab X @tab X
242@item H.263(+) @tab X @tab X
d698c5d3 243 @tab also known as RealVideo 1.0
82ced5a9 244@item H.264 @tab E @tab X
360f980b 245 @tab encoding supported through external library libx264
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246@item HuffYUV @tab X @tab X
247@item IBM Ultimotion @tab @tab X
d698c5d3 248 @tab fourcc: ULTI
bac4c85c 249@item id Cinematic video @tab @tab X
d698c5d3 250 @tab Used in Quake II.
d66d8b83 251@item id RoQ @tab X @tab X
d698c5d3 252 @tab Used in Quake III, Jedi Knight 2, other computer games.
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253@item Intel Indeo 3 @tab @tab X
254@item Interplay Video @tab @tab X
d698c5d3 255 @tab Used in Interplay .MVE files.
d66d8b83 256@item JPEG-LS @tab X @tab X
d698c5d3 257 @tab fourcc: MJLS, lossless and near-lossless is supported.
d66d8b83 258@item KMVC @tab @tab X
d698c5d3 259 @tab Codec used in Worms games.
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260@item LOCO @tab @tab X
261@item lossless MJPEG @tab X @tab X
262@item Microsoft RLE @tab @tab X
263@item Microsoft Video-1 @tab @tab X
264@item Mimic @tab @tab X
d698c5d3 265 @tab Used in MSN Messenger Webcam streams.
d66d8b83 266@item Miro VideoXL @tab @tab X
d698c5d3 267 @tab fourcc: VIXL
d66d8b83 268@item MJPEG @tab X @tab X
822cc8f7 269@item Motion Pixels Video @tab @tab X
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270@item MPEG-1 @tab X @tab X
271@item MPEG-2 @tab X @tab X
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272@item MPEG-4 @tab X @tab X
273@item MSMPEG4 V1 @tab X @tab X
274@item MSMPEG4 V2 @tab X @tab X
275@item MSMPEG4 V3 @tab X @tab X
d66d8b83 276@item MSZH @tab @tab X
d698c5d3 277 @tab Part of LCL
d66d8b83 278@item On2 VP3 @tab @tab X
d698c5d3 279 @tab still experimental
d66d8b83 280@item On2 VP5 @tab @tab X
d698c5d3 281 @tab fourcc: VP50
d66d8b83 282@item On2 VP6 @tab @tab X
d698c5d3 283 @tab fourcc: VP60,VP61,VP62
d66d8b83 284@item planar RGB @tab @tab X
d698c5d3 285 @tab fourcc: 8BPS
d66d8b83 286@item QPEG @tab @tab X
d698c5d3 287 @tab fourccs: QPEG, Q1.0, Q1.1
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288@item RealVideo 1.0 @tab X @tab X
289@item RealVideo 2.0 @tab X @tab X
d66d8b83 290@item Renderware TXD @tab @tab X
d698c5d3 291 @tab Texture dictionaries used by the Renderware Engine.
d66d8b83 292@item RTjpeg @tab @tab X
d698c5d3 293 @tab Video encoding used in NuppelVideo files.
bac4c85c 294@item Smacker video @tab @tab X
d698c5d3 295 @tab Video encoding used in Smacker.
d66d8b83 296@item Snow @tab X @tab X
d698c5d3 297 @tab experimental wavelet codec (fourcc: SNOW)
831ec935 298@item Sony PlayStation MDEC @tab @tab X
d66d8b83 299@item Sorenson Video 1 @tab X @tab X
d698c5d3 300 @tab fourcc: SVQ1
d66d8b83 301@item Sorenson Video 3 @tab @tab X
d698c5d3 302 @tab fourcc: SVQ3
d66d8b83 303@item Sunplus MJPEG @tab @tab X
d698c5d3 304 @tab fourcc: SP5X
d66d8b83 305@item TechSmith Camtasia @tab @tab X
d698c5d3 306 @tab fourcc: TSCC
82ced5a9 307@item Theora @tab E @tab X
360f980b 308 @tab encoding supported through external library libtheora
d66d8b83 309@item THP @tab @tab X
d698c5d3 310 @tab Used on the Nintendo GameCube.
bac4c85c 311@item Tiertex Seq video @tab @tab X
d698c5d3 312 @tab Codec used in DOS CD-ROM FlashBack game.
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313@item VC-1 @tab @tab X
314@item VMD Video @tab @tab X
d698c5d3 315 @tab Used in Sierra VMD files.
d66d8b83 316@item VMware Video @tab @tab X
d698c5d3 317 @tab Codec used in videos captured by VMware.
d0e1cd3d 318@item Westwood VQA @tab @tab X
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319@item Winnov WNV1 @tab @tab X
320@item WMV7 @tab X @tab X
321@item WMV8 @tab X @tab X
322@item WMV9 @tab @tab X
d698c5d3 323 @tab not completely working
d66d8b83 324@item Xan/WC3 @tab @tab X
d698c5d3 325 @tab Used in Wing Commander III .MVE files.
d66d8b83 326@item ZLIB @tab X @tab X
d698c5d3 327 @tab part of LCL, encoder experimental
d66d8b83 328@item ZMBV @tab X @tab X
d698c5d3 329 @tab Encoder works only in PAL8.
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330@end multitable
331
332@code{X} means that encoding (resp. decoding) is supported.
333
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334@code{E} means that support is provided through an external library.
335
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336@section Audio Codecs
337
338@multitable @columnfractions .4 .1 .1 .1 .7
b3de4544 339@item Name @tab Encoding @tab Decoding @tab Comments
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340@item 4X IMA ADPCM @tab @tab X
341@item 8SVX audio @tab @tab X
82ced5a9 342@item AAC @tab E @tab X
360f980b 343 @tab encoding supported through external library libfaac
16d81b27 344@item AC-3 @tab IX @tab IX
82ced5a9 345@item AMR-NB @tab E @tab E
360f980b 346 @tab supported through external library libamrnb
82ced5a9 347@item AMR-WB @tab E @tab E
360f980b 348 @tab supported through external library libamrwb
16d81b27 349@item AMV IMA ADPCM @tab @tab X
d698c5d3 350 @tab Used in AMV files
833e90dd 351@item Apple lossless audio @tab X @tab X
d698c5d3 352 @tab QuickTime fourcc 'alac'
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353@item Apple MACE 3 @tab @tab X
354@item Apple MACE 6 @tab @tab X
355@item ATRAC 3 @tab @tab X
356@item CD-ROM XA ADPCM @tab @tab X
bac4c85c 357@item Cin audio @tab @tab X
d698c5d3 358 @tab Codec used in Delphine Software International games.
16d81b27 359@item Creative ADPCM @tab @tab X
d698c5d3 360 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
16d81b27 361@item CRI ADX ADPCM @tab X @tab X
d698c5d3 362 @tab Used in Sega Dreamcast games.
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363@item DSP Group TrueSpeech @tab @tab X
364@item DTS Coherent Audio @tab @tab X
365@item Duck DK3 IMA ADPCM @tab @tab X
d698c5d3 366 @tab Used in some Sega Saturn console games.
16d81b27 367@item Duck DK4 IMA ADPCM @tab @tab X
d698c5d3 368 @tab Used in some Sega Saturn console games.
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369@item DV audio @tab @tab X
370@item Electronic Arts ADPCM @tab @tab X
d698c5d3 371 @tab Used in various EA titles.
44723c84 372@item Enhanced AC-3 @tab @tab X
9a584db4 373@item FLAC lossless audio @tab IX @tab X
16d81b27 374@item G.726 ADPCM @tab X @tab X
82ced5a9 375@item GSM @tab E @tab E
3f33271a 376 @tab supported through external library libgsm
82ced5a9 377@item GSM_MS @tab E @tab E
3f33271a 378 @tab supported through external library libgsm
16d81b27 379@item id RoQ DPCM @tab X @tab X
d698c5d3 380 @tab Used in Quake III, Jedi Knight 2, other computer games.
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381@item Intel Music Coder @tab @tab X
382@item Interplay MVE DPCM @tab @tab X
d698c5d3 383 @tab Used in various Interplay computer games.
16d81b27 384@item MAXIS EA ADPCM @tab @tab X
d698c5d3 385 @tab Used in Sim City 3000.
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386@item Microsoft ADPCM @tab X @tab X
387@item MLP/TrueHD @tab @tab X
d698c5d3 388 @tab Used in DVD-Audio and Blu-Ray discs.
16d81b27 389@item Monkey's Audio @tab @tab X
d698c5d3 390 @tab Only versions 3.97-3.99 are supported.
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391@item MPEG audio layer 3 @tab E @tab IX
392 @tab encoding supported through external library LAME
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393@item MPEG audio layer 2 @tab IX @tab IX
394@item MS IMA ADPCM @tab X @tab X
395@item Musepack @tab @tab X
d698c5d3 396 @tab SV7 and SV8 are supported.
755ba886 397@item Nellymoser ASAO @tab X @tab X
16d81b27 398@item Qdesign QDM2 @tab @tab X
d698c5d3 399 @tab There are still some distortions.
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400@item QT IMA ADPCM @tab X @tab X
401@item RA144 @tab @tab X
d698c5d3 402 @tab Real 14400 bit/s codec
16d81b27 403@item RA288 @tab @tab X
d698c5d3 404 @tab Real 28800 bit/s codec
575a5bf2 405@item RADnet @tab IX @tab IX
a692130f 406 @tab Real low bitrate AC-3 codec
16d81b27 407@item Real COOK @tab @tab X
d698c5d3 408 @tab All versions except 5.1 are supported.
bac4c85c 409@item Shorten @tab @tab X
16d81b27 410@item Sierra Online DPCM @tab @tab X
d698c5d3 411 @tab Used in Sierra Online game audio files.
bac4c85c 412@item Smacker audio @tab @tab X
16d81b27 413@item SMJPEG IMA ADPCM @tab @tab X
d698c5d3 414 @tab Used in certain Loki game ports.
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415@item Sonic @tab X @tab X
416 @tab experimental codec
417@item Sonic lossless @tab X @tab X
418 @tab experimental codec
82ced5a9 419@item Speex @tab @tab E
360f980b 420 @tab supported through external library libspeex
16d81b27 421@item THP ADPCM @tab @tab X
d698c5d3 422 @tab Used on the Nintendo GameCube.
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423@item True Audio (TTA) @tab @tab X
424@item Vorbis @tab X @tab X
bac4c85c 425@item WavPack @tab @tab X
16d81b27 426@item Westwood Studios IMA ADPCM @tab @tab X
d698c5d3 427 @tab Used in Westwood Studios games like Command and Conquer.
bac4c85c 428@item WMA v1/v2 @tab X @tab X
16d81b27 429@item Xan DPCM @tab @tab X
d698c5d3 430 @tab Used in Origin's Wing Commander IV AVI files.
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431@end multitable
432
433@code{X} means that encoding (resp. decoding) is supported.
434
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435@code{E} means that support is provided through an external library.
436
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437@code{I} means that an integer-only version is available, too (ensures high
438performance on systems without hardware floating point support).
439
440@chapter Platform Specific information
441
442@section BSD
443
444BSD make will not build FFmpeg, you need to install and use GNU Make
445(@file{gmake}).
446
447@section Windows
448
46a845d0 449To get help and instructions for building FFmpeg under Windows, check out
d0e1cd3d 450the FFmpeg Windows Help Forum at
ab5ce4ae 451@url{http://ffmpeg.arrozcru.org/}.
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452
453@subsection Native Windows compilation
454
c1989552 455FFmpeg can be built to run natively on Windows using the MinGW tools. Install
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456the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
457You can find detailed installation
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458instructions in the download section and the FAQ.
459
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460FFmpeg does not build out-of-the-box with the packages the automated MinGW
461installer provides. It also requires coreutils to be installed and many other
462packages updated to the latest version. The minimum version for some packages
463are listed below:
464
465@itemize
466@item bash 3.1
467@item msys-make 3.81-2 (note: not mingw32-make)
468@item w32api 3.12
469@item mingw-runtime 3.15
470@end itemize
471
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472You will also need to pass @code{-fno-common} to the compiler to work around
473a GCC bug (see @url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216}).
474
c1989552 475Within the MSYS shell, configure and make with:
d0e1cd3d 476
c1989552 477@example
0f898714 478./configure --enable-memalign-hack --extra-cflags=-fno-common
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479make
480make install
481@end example
d0e1cd3d 482
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483This will install @file{ffmpeg.exe} along with many other development files
484to @file{/usr/local}. You may specify another install path using the
485@code{--prefix} option in @file{configure}.
d0e1cd3d 486
c1989552 487Notes:
d0e1cd3d 488
c1989552 489@itemize
d0e1cd3d 490
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491@item In order to compile vhooks, you must have a POSIX-compliant libdl in
492your MinGW system. Get dlfcn-win32 from
493@url{http://code.google.com/p/dlfcn-win32}.
d0e1cd3d 494
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495@item In order to compile FFplay, you must have the MinGW development library
496of SDL. Get it from @url{http://www.libsdl.org}.
497Edit the @file{bin/sdl-config} script so that it points to the correct prefix
498where SDL was installed. Verify that @file{sdl-config} can be launched from
499the MSYS command line.
d0e1cd3d 500
d0e1cd3d 501@item By using @code{./configure --enable-shared} when configuring FFmpeg,
c1989552 502you can build libavutil, libavcodec and libavformat as DLLs.
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503
504@end itemize
505
c1989552 506@subsection Microsoft Visual C++ compatibility
d0e1cd3d 507
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508As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
509want to use the libav* libraries in your own applications, you can still
510compile those applications using MSVC++. But the libav* libraries you link
511to @emph{must} be built with MinGW. However, you will not be able to debug
512inside the libav* libraries, since MSVC++ does not recognize the debug
513symbols generated by GCC.
514We strongly recommend you to move over from MSVC++ to MinGW tools.
d0e1cd3d 515
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516This description of how to use the FFmpeg libraries with MSVC++ is based on
517Microsoft Visual C++ 2005 Express Edition. If you have a different version,
518you might have to modify the procedures slightly.
d0e1cd3d 519
c1989552 520@subsubsection Using static libraries
d0e1cd3d 521
c1989552 522Assuming you have just built and installed FFmpeg in @file{/usr/local}.
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523
524@enumerate
525
526@item Create a new console application ("File / New / Project") and then
527select "Win32 Console Application". On the appropriate page of the
528Application Wizard, uncheck the "Precompiled headers" option.
529
530@item Write the source code for your application, or, for testing, just
531copy the code from an existing sample application into the source file
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532that MSVC++ has already created for you. For example, you can copy
533@file{output_example.c} from the FFmpeg distribution.
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534
535@item Open the "Project / Properties" dialog box. In the "Configuration"
536combo box, select "All Configurations" so that the changes you make will
537affect both debug and release builds. In the tree view on the left hand
538side, select "C/C++ / General", then edit the "Additional Include
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539Directories" setting to contain the path where the FFmpeg includes were
540installed (i.e. @file{c:\msys\1.0\local\include}).
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541Do not add MinGW's include directory here, or the include files will
542conflict with MSVC's.
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543
544@item Still in the "Project / Properties" dialog box, select
545"Linker / General" from the tree view and edit the
546"Additional Library Directories" setting to contain the @file{lib}
547directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
548the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
549and the directory where MinGW's GCC libs are installed
550(i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
551"Linker / Input" from the tree view, and add the files @file{libavformat.a},
552@file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
553@file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
554to the end of "Additional Dependencies".
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555
556@item Now, select "C/C++ / Code Generation" from the tree view. Select
557"Debug" in the "Configuration" combo box. Make sure that "Runtime
558Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
559the "Configuration" combo box and make sure that "Runtime Library" is
560set to "Multi-threaded DLL".
561
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562@item Click "OK" to close the "Project / Properties" dialog box.
563
564@item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
565Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
566and install it in MSVC++'s include directory
567(i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
568
569@item MSVC++ also does not understand the @code{inline} keyword used by
570FFmpeg, so you must add this line before @code{#include}ing libav*:
571@example
572#define inline _inline
573@end example
574
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575@item Build your application, everything should work.
576
577@end enumerate
578
579@subsubsection Using shared libraries
580
581This is how to create DLL and LIB files that are compatible with MSVC++:
582
583@enumerate
584
585@item Add a call to @file{vcvars32.bat} (which sets up the environment
586variables for the Visual C++ tools) as the first line of @file{msys.bat}.
587The standard location for @file{vcvars32.bat} is
588@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
589and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
590If this corresponds to your setup, add the following line as the first line
591of @file{msys.bat}:
592
593@example
594call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
595@end example
596
597Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
598and run @file{c:\msys\1.0\msys.bat} from there.
599
600@item Within the MSYS shell, run @code{lib.exe}. If you get a help message
601from @file{Microsoft (R) Library Manager}, this means your environment
602variables are set up correctly, the @file{Microsoft (R) Library Manager}
603is on the path and will be used by FFmpeg to create
604MSVC++-compatible import libraries.
605
606@item Build FFmpeg with
607
608@example
609./configure --enable-shared --enable-memalign-hack
610make
611make install
612@end example
613
614Your install path (@file{/usr/local/} by default) should now have the
615necessary DLL and LIB files under the @file{bin} directory.
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616
617@end enumerate
618
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619To use those files with MSVC++, do the same as you would do with
620the static libraries, as described above. But in Step 4,
621you should only need to add the directory where the LIB files are installed
622(i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
623installed in the @file{bin} directory. And instead of adding @file{libxx.a}
624files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
625@file{avutil.lib}. There should be no need for @file{libmingwex.a},
626@file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
627statically linked into the DLLs. The @file{bin} directory contains a bunch
628of DLL files, but the ones that are actually used to run your application
629are the ones with a major version number in their filenames
630(i.e. @file{avcodec-51.dll}).
631
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632@subsection Cross compilation for Windows with Linux
633
634You must use the MinGW cross compilation tools available at
635@url{http://www.mingw.org/}.
636
637Then configure FFmpeg with the following options:
638@example
639./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
640@end example
641(you can change the cross-prefix according to the prefix chosen for the
642MinGW tools).
643
644Then you can easily test FFmpeg with Wine
645(@url{http://www.winehq.com/}).
646
647@subsection Compilation under Cygwin
648
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649The main issue with Cygwin is that newlib, its C library, does not
650contain llrint(). However, it is possible to leverage the
651implementation in MinGW.
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652
653Just install your Cygwin with all the "Base" packages, plus the
654following "Devel" ones:
655@example
29c3d42b 656binutils, gcc-core, make, subversion, mingw-runtime
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657@end example
658
659Do not install binutils-20060709-1 (they are buggy on shared builds);
660use binutils-20050610-1 instead.
661
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662Then create a small library that just contains llrint():
663
664@example
665ar x /usr/lib/mingw/libmingwex.a llrint.o
666ar cq /usr/local/lib/libllrint.a llrint.o
667@end example
668
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669Then run
670
671@example
29c3d42b 672./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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673@end example
674
675to make a static build or
676
677@example
29c3d42b 678./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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679@end example
680
681to build shared libraries.
682
683If you want to build FFmpeg with additional libraries, download Cygwin
684"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
685and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
686(@url{http://cygwinports.dotsrc.org/}).
687
688@subsection Crosscompilation for Windows under Cygwin
689
690With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
691
692Just install your Cygwin as explained before, plus these additional
693"Devel" packages:
694@example
695gcc-mingw-core, mingw-runtime, mingw-zlib
696@end example
697
698and add some special flags to your configure invocation.
699
700For a static build run
701@example
702./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
703@end example
704
705and for a build with shared libraries
706@example
707./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
708@end example
709
710@section BeOS
711
5f757b85 712BeOS support is broken in mysterious ways.
d0e1cd3d 713
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714@section OS/2
715
716For information about compiling FFmpeg on OS/2 see
717@url{http://www.edm2.com/index.php/FFmpeg}.
718
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719@chapter Developers Guide
720
721@section API
722@itemize @bullet
723@item libavcodec is the library containing the codecs (both encoding and
724decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
725
726@item libavformat is the library containing the file format handling (mux and
727demux code for several formats). Look at @file{ffplay.c} to use it in a
728player. See @file{output_example.c} to use it to generate audio or video
729streams.
730
731@end itemize
732
733@section Integrating libavcodec or libavformat in your program
734
735You can integrate all the source code of the libraries to link them
736statically to avoid any version problem. All you need is to provide a
737'config.mak' and a 'config.h' in the parent directory. See the defines
738generated by ./configure to understand what is needed.
739
740You can use libavcodec or libavformat in your commercial program, but
741@emph{any patch you make must be published}. The best way to proceed is
742to send your patches to the FFmpeg mailing list.
743
744@node Coding Rules
745@section Coding Rules
746
747FFmpeg is programmed in the ISO C90 language with a few additional
748features from ISO C99, namely:
749@itemize @bullet
750@item
751the @samp{inline} keyword;
752@item
753@samp{//} comments;
754@item
755designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
756@item
757compound literals (@samp{x = (struct s) @{ 17, 23 @};})
758@end itemize
759
760These features are supported by all compilers we care about, so we will not
761accept patches to remove their use unless they absolutely do not impair
762clarity and performance.
763
764All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
765compiles with several other compilers, such as the Compaq ccc compiler
766or Sun Studio 9, and we would like to keep it that way unless it would
767be exceedingly involved. To ensure compatibility, please do not use any
768additional C99 features or GCC extensions. Especially watch out for:
769@itemize @bullet
770@item
771mixing statements and declarations;
772@item
773@samp{long long} (use @samp{int64_t} instead);
774@item
775@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
776@item
777GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
778@end itemize
779
780Indent size is 4.
781The presentation is the one specified by 'indent -i4 -kr -nut'.
782The TAB character is forbidden outside of Makefiles as is any
783form of trailing whitespace. Commits containing either will be
784rejected by the Subversion repository.
785
786The main priority in FFmpeg is simplicity and small code size in order to
787minimize the bug count.
788
789Comments: Use the JavaDoc/Doxygen
790format (see examples below) so that code documentation
791can be generated automatically. All nontrivial functions should have a comment
792above them explaining what the function does, even if it is just one sentence.
793All structures and their member variables should be documented, too.
794@example
795/**
796 * @@file mpeg.c
797 * MPEG codec.
798 * @@author ...
799 */
800
801/**
802 * Summary sentence.
803 * more text ...
804 * ...
805 */
806typedef struct Foobar@{
807 int var1; /**< var1 description */
808 int var2; ///< var2 description
809 /** var3 description */
810 int var3;
811@} Foobar;
812
813/**
814 * Summary sentence.
815 * more text ...
816 * ...
817 * @@param my_parameter description of my_parameter
818 * @@return return value description
819 */
820int myfunc(int my_parameter)
821...
822@end example
823
824fprintf and printf are forbidden in libavformat and libavcodec,
825please use av_log() instead.
826
827Casts should be used only when necessary. Unneeded parentheses
828should also be avoided if they don't make the code easier to understand.
829
830@section Development Policy
831
832@enumerate
833@item
834 Contributions should be licensed under the LGPL 2.1, including an
835 "or any later version" clause, or the MIT license. GPL 2 including
836 an "or any later version" clause is also acceptable, but LGPL is
837 preferred.
838@item
839 You must not commit code which breaks FFmpeg! (Meaning unfinished but
840 enabled code which breaks compilation or compiles but does not work or
841 breaks the regression tests)
842 You can commit unfinished stuff (for testing etc), but it must be disabled
843 (#ifdef etc) by default so it does not interfere with other developers'
844 work.
845@item
846 You do not have to over-test things. If it works for you, and you think it
847 should work for others, then commit. If your code has problems
848 (portability, triggers compiler bugs, unusual environment etc) they will be
849 reported and eventually fixed.
850@item
851 Do not commit unrelated changes together, split them into self-contained
852 pieces. Also do not forget that if part B depends on part A, but A does not
853 depend on B, then A can and should be committed first and separate from B.
854 Keeping changes well split into self-contained parts makes reviewing and
855 understanding them on the commit log mailing list easier. This also helps
856 in case of debugging later on.
857 Also if you have doubts about splitting or not splitting, do not hesitate to
858 ask/discuss it on the developer mailing list.
859@item
860 Do not change behavior of the program (renaming options etc) without
861 first discussing it on the ffmpeg-devel mailing list. Do not remove
862 functionality from the code. Just improve!
863
864 Note: Redundant code can be removed.
865@item
866 Do not commit changes to the build system (Makefiles, configure script)
867 which change behavior, defaults etc, without asking first. The same
868 applies to compiler warning fixes, trivial looking fixes and to code
869 maintained by other developers. We usually have a reason for doing things
870 the way we do. Send your changes as patches to the ffmpeg-devel mailing
871 list, and if the code maintainers say OK, you may commit. This does not
872 apply to files you wrote and/or maintain.
873@item
874 We refuse source indentation and other cosmetic changes if they are mixed
875 with functional changes, such commits will be rejected and removed. Every
876 developer has his own indentation style, you should not change it. Of course
877 if you (re)write something, you can use your own style, even though we would
878 prefer if the indentation throughout FFmpeg was consistent (Many projects
879 force a given indentation style - we do not.). If you really need to make
880 indentation changes (try to avoid this), separate them strictly from real
881 changes.
882
883 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
884 then either do NOT change the indentation of the inner part within (do not
885 move it to the right)! or do so in a separate commit
886@item
887 Always fill out the commit log message. Describe in a few lines what you
888 changed and why. You can refer to mailing list postings if you fix a
889 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
890@item
891 If you apply a patch by someone else, include the name and email address in
892 the log message. Since the ffmpeg-cvslog mailing list is publicly
893 archived you should add some SPAM protection to the email address. Send an
894 answer to ffmpeg-devel (or wherever you got the patch from) saying that
895 you applied the patch.
896@item
897 When applying patches that have been discussed (at length) on the mailing
898 list, reference the thread in the log message.
899@item
900 Do NOT commit to code actively maintained by others without permission.
901 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
902 timeframe (12h for build failures and security fixes, 3 days small changes,
903 1 week for big patches) then commit your patch if you think it is OK.
904 Also note, the maintainer can simply ask for more time to review!
905@item
906 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
907 are sent there and reviewed by all the other developers. Bugs and possible
908 improvements or general questions regarding commits are discussed there. We
909 expect you to react if problems with your code are uncovered.
910@item
911 Update the documentation if you change behavior or add features. If you are
912 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
913 maintainer(s) will review and commit your stuff.
914@item
915 Try to keep important discussions and requests (also) on the public
916 developer mailing list, so that all developers can benefit from them.
917@item
918 Never write to unallocated memory, never write over the end of arrays,
919 always check values read from some untrusted source before using them
920 as array index or other risky things.
921@item
922 Remember to check if you need to bump versions for the specific libav
923 parts (libavutil, libavcodec, libavformat) you are changing. You need
b98052d5 924 to change the version integer.
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925 Incrementing the first component means no backward compatibility to
926 previous versions (e.g. removal of a function from the public API).
927 Incrementing the second component means backward compatible change
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928 (e.g. addition of a function to the public API or extension of an
929 existing data structure).
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930 Incrementing the third component means a noteworthy binary compatible
931 change (e.g. encoder bug fix that matters for the decoder).
932@item
53407b64 933 Compiler warnings indicate potential bugs or code with bad style. If a type of
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934 warning always points to correct and clean code, that warning should
935 be disabled, not the code changed.
936 Thus the remaining warnings can either be bugs or correct code.
beaa4a91 937 If it is a bug, the bug has to be fixed. If it is not, the code should
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938 be changed to not generate a warning unless that causes a slowdown
939 or obfuscates the code.
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940@item
941 If you add a new file, give it a proper license header. Do not copy and
942 paste it from a random place, use an existing file as template.
943@end enumerate
944
945We think our rules are not too hard. If you have comments, contact us.
946
947Note, these rules are mostly borrowed from the MPlayer project.
948
949@section Submitting patches
950
951First, (@pxref{Coding Rules}) above if you did not yet.
952
953When you submit your patch, try to send a unified diff (diff '-up'
954option). We cannot read other diffs :-)
955
956Also please do not submit a patch which contains several unrelated changes.
957Split it into separate, self-contained pieces. This does not mean splitting
958file by file. Instead, make the patch as small as possible while still
959keeping it as a logical unit that contains an individual change, even
960if it spans multiple files. This makes reviewing your patches much easier
961for us and greatly increases your chances of getting your patch applied.
962
963Run the regression tests before submitting a patch so that you can
964verify that there are no big problems.
965
966Patches should be posted as base64 encoded attachments (or any other
967encoding which ensures that the patch will not be trashed during
968transmission) to the ffmpeg-devel mailing list, see
969@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
970
971It also helps quite a bit if you tell us what the patch does (for example
972'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
973and has no lrint()')
974
975Also please if you send several patches, send each patch as a separate mail,
976do not attach several unrelated patches to the same mail.
977
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978@section New codecs or formats checklist
979
980@enumerate
981@item
982 Did you use av_cold for codec initialization and close functions?
983@item
984 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
985 AVInputFormat/AVOutputFormat struct?
986@item
987 Did you bump the minor version number in @file{avcodec.h} or
988 @file{avformat.h}?
989@item
990 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
991@item
992 Did you add the CodecID to @file{avcodec.h}?
993@item
994 If it has a fourcc, did you add it to @file{libavformat/riff.c},
995 even if it is only a decoder?
996@item
997 Did you add a rule to compile the appropriate files in the Makefile?
998 Remember to do this even if you're just adding a format to a file that is
999 already being compiled by some other rule, like a raw demuxer.
1000@item
1001 Did you add an entry to the table of supported formats or codecs in the
1002 documentation?
1003@item
1004 Did you add an entry in the Changelog?
1005@item
1006 If it depends on a parser or a library, did you add that dependency in
1007 configure?
1008@item
1009 Did you "svn add" the appropriate files before commiting?
1010@end enumerate
1011
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1012@section patch submission checklist
1013
1014@enumerate
1015@item
1016 Do the regression tests pass with the patch applied?
1017@item
1018 Is the patch a unified diff?
1019@item
1020 Is the patch against latest FFmpeg SVN?
1021@item
1022 Are you subscribed to ffmpeg-dev?
1023 (the list is subscribers only due to spam)
1024@item
1025 Have you checked that the changes are minimal, so that the same cannot be
1026 achieved with a smaller patch and/or simpler final code?
1027@item
1028 If the change is to speed critical code, did you benchmark it?
1029@item
1030 If you did any benchmarks, did you provide them in the mail?
1031@item
1032 Have you checked that the patch does not introduce buffer overflows or
1033 other security issues?
1034@item
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1035 If you add a new demuxer or decoder, have you checked that it does not
1036 crash with damaged input (see tools/trasher)?
1037@item
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1038 Is the patch created from the root of the source tree, so it can be
1039 applied with @code{patch -p0}?
1040@item
1041 Does the patch not mix functional and cosmetic changes?
1042@item
1043 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1044@item
1045 Is the patch attached to the email you send?
1046@item
1047 Is the mime type of the patch correct? It should be text/x-diff or
1048 text/x-patch or at least text/plain and not application/octet-stream.
1049@item
1050 If the patch fixes a bug, did you provide a verbose analysis of the bug?
1051@item
1052 If the patch fixes a bug, did you provide enough information, including
1053 a sample, so the bug can be reproduced and the fix can be verified?
1054 Note please do not attach samples >100k to mails but rather provide a
1055 URL, you can upload to ftp://upload.mplayerhq.hu
1056@item
1057 Did you provide a verbose summary about what the patch does change?
1058@item
1059 Did you provide a verbose explanation why it changes things like it does?
1060@item
1061 Did you provide a verbose summary of the user visible advantages and
1062 disadvantages if the patch is applied?
1063@item
1064 Did you provide an example so we can verify the new feature added by the
1065 patch easily?
1066@item
1067 If you added a new file, did you insert a license header? It should be
1068 taken from FFmpeg, not randomly copied and pasted from somewhere else.
1069@item
1070 You should maintain alphabetical order in alphabetically ordered lists as
1071 long as doing so does not break API/ABI compatibility.
1072@item
1073 Lines with similar content should be aligned vertically when doing so
1074 improves readability.
1075@item
1076 Did you provide a suggestion for a clear commit log message?
27250d20
MN
1077@item
1078 Did you test your decoder or demuxer against damaged data? If no, see
1079 tools/trasher and the noise bitstream filter. Your decoder or demuxer
fe74278f 1080 should not crash or end in a (near) infinite loop when fed damaged data.
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DB
1081@end enumerate
1082
1083@section Patch review process
1084
1085All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1086clear note that the patch is not for SVN.
1087Reviews and comments will be posted as replies to the patch on the
1088mailing list. The patch submitter then has to take care of every comment,
1089that can be by resubmitting a changed patch or by discussion. Resubmitted
1090patches will themselves be reviewed like any other patch. If at some point
1091a patch passes review with no comments then it is approved, that can for
1092simple and small patches happen immediately while large patches will generally
1093have to be changed and reviewed many times before they are approved.
1094After a patch is approved it will be committed to the repository.
1095
1096We will review all submitted patches, but sometimes we are quite busy so
1097especially for large patches this can take several weeks.
1098
1099When resubmitting patches, please do not make any significant changes
1100not related to the comments received during review. Such patches will
1101be rejected. Instead, submit significant changes or new features as
1102separate patches.
1103
1104@section Regression tests
1105
1106Before submitting a patch (or committing to the repository), you should at least
1107test that you did not break anything.
1108
1109The regression tests build a synthetic video stream and a synthetic
1110audio stream. These are then encoded and decoded with all codecs or
1111formats. The CRC (or MD5) of each generated file is recorded in a
1112result file. A 'diff' is launched to compare the reference results and
1113the result file.
1114
1115The regression tests then go on to test the FFserver code with a
1116limited set of streams. It is important that this step runs correctly
1117as well.
1118
1119Run 'make test' to test all the codecs and formats.
1120
1121Run 'make fulltest' to test all the codecs, formats and FFserver.
1122
1123[Of course, some patches may change the results of the regression tests. In
1124this case, the reference results of the regression tests shall be modified
1125accordingly].
1126
1127@bye