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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
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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
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221@item Dirac @tab X @tab X
222 @tab Supported through the 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
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244@item H.264 @tab @tab X
245@item HuffYUV @tab X @tab X
246@item IBM Ultimotion @tab @tab X
d698c5d3 247 @tab fourcc: ULTI
bac4c85c 248@item id Cinematic video @tab @tab X
d698c5d3 249 @tab Used in Quake II.
d66d8b83 250@item id RoQ @tab X @tab X
d698c5d3 251 @tab Used in Quake III, Jedi Knight 2, other computer games.
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252@item Intel Indeo 3 @tab @tab X
253@item Interplay Video @tab @tab X
d698c5d3 254 @tab Used in Interplay .MVE files.
d66d8b83 255@item JPEG-LS @tab X @tab X
d698c5d3 256 @tab fourcc: MJLS, lossless and near-lossless is supported.
d66d8b83 257@item KMVC @tab @tab X
d698c5d3 258 @tab Codec used in Worms games.
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259@item LOCO @tab @tab X
260@item lossless MJPEG @tab X @tab X
261@item Microsoft RLE @tab @tab X
262@item Microsoft Video-1 @tab @tab X
263@item Mimic @tab @tab X
d698c5d3 264 @tab Used in MSN Messenger Webcam streams.
d66d8b83 265@item Miro VideoXL @tab @tab X
d698c5d3 266 @tab fourcc: VIXL
d66d8b83 267@item MJPEG @tab X @tab X
822cc8f7 268@item Motion Pixels Video @tab @tab X
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269@item MPEG-1 @tab X @tab X
270@item MPEG-2 @tab X @tab X
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271@item MPEG-4 @tab X @tab X
272@item MSMPEG4 V1 @tab X @tab X
273@item MSMPEG4 V2 @tab X @tab X
274@item MSMPEG4 V3 @tab X @tab X
d66d8b83 275@item MSZH @tab @tab X
d698c5d3 276 @tab Part of LCL
d66d8b83 277@item On2 VP3 @tab @tab X
d698c5d3 278 @tab still experimental
d66d8b83 279@item On2 VP5 @tab @tab X
d698c5d3 280 @tab fourcc: VP50
d66d8b83 281@item On2 VP6 @tab @tab X
d698c5d3 282 @tab fourcc: VP60,VP61,VP62
d66d8b83 283@item planar RGB @tab @tab X
d698c5d3 284 @tab fourcc: 8BPS
d66d8b83 285@item QPEG @tab @tab X
d698c5d3 286 @tab fourccs: QPEG, Q1.0, Q1.1
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287@item RealVideo 1.0 @tab X @tab X
288@item RealVideo 2.0 @tab X @tab X
d66d8b83 289@item Renderware TXD @tab @tab X
d698c5d3 290 @tab Texture dictionaries used by the Renderware Engine.
d66d8b83 291@item RTjpeg @tab @tab X
d698c5d3 292 @tab Video encoding used in NuppelVideo files.
bac4c85c 293@item Smacker video @tab @tab X
d698c5d3 294 @tab Video encoding used in Smacker.
d66d8b83 295@item Snow @tab X @tab X
d698c5d3 296 @tab experimental wavelet codec (fourcc: SNOW)
831ec935 297@item Sony PlayStation MDEC @tab @tab X
d66d8b83 298@item Sorenson Video 1 @tab X @tab X
d698c5d3 299 @tab fourcc: SVQ1
d66d8b83 300@item Sorenson Video 3 @tab @tab X
d698c5d3 301 @tab fourcc: SVQ3
d66d8b83 302@item Sunplus MJPEG @tab @tab X
d698c5d3 303 @tab fourcc: SP5X
d66d8b83 304@item TechSmith Camtasia @tab @tab X
d698c5d3 305 @tab fourcc: TSCC
d66d8b83 306@item Theora @tab X @tab X
d698c5d3 307 @tab still experimental
d66d8b83 308@item THP @tab @tab X
d698c5d3 309 @tab Used on the Nintendo GameCube.
bac4c85c 310@item Tiertex Seq video @tab @tab X
d698c5d3 311 @tab Codec used in DOS CD-ROM FlashBack game.
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312@item VC-1 @tab @tab X
313@item VMD Video @tab @tab X
d698c5d3 314 @tab Used in Sierra VMD files.
d66d8b83 315@item VMware Video @tab @tab X
d698c5d3 316 @tab Codec used in videos captured by VMware.
d0e1cd3d 317@item Westwood VQA @tab @tab X
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318@item Winnov WNV1 @tab @tab X
319@item WMV7 @tab X @tab X
320@item WMV8 @tab X @tab X
321@item WMV9 @tab @tab X
d698c5d3 322 @tab not completely working
d66d8b83 323@item Xan/WC3 @tab @tab X
d698c5d3 324 @tab Used in Wing Commander III .MVE files.
d66d8b83 325@item ZLIB @tab X @tab X
d698c5d3 326 @tab part of LCL, encoder experimental
d66d8b83 327@item ZMBV @tab X @tab X
d698c5d3 328 @tab Encoder works only in PAL8.
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329@end multitable
330
331@code{X} means that encoding (resp. decoding) is supported.
332
333@section Audio Codecs
334
335@multitable @columnfractions .4 .1 .1 .1 .7
b3de4544 336@item Name @tab Encoding @tab Decoding @tab Comments
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337@item 4X IMA ADPCM @tab @tab X
338@item 8SVX audio @tab @tab X
339@item AAC @tab X @tab X
7d8f3de4 340 @tab Encoding is supported through the external library libfaac.
16d81b27 341@item AC-3 @tab IX @tab IX
d698c5d3 342 @tab liba52 can be used alternatively for decoding.
16d81b27 343@item AMR-NB @tab X @tab X
d698c5d3 344 @tab Supported through an external library.
16d81b27 345@item AMR-WB @tab X @tab X
d698c5d3 346 @tab Supported through an external library.
16d81b27 347@item AMV IMA ADPCM @tab @tab X
d698c5d3 348 @tab Used in AMV files
833e90dd 349@item Apple lossless audio @tab X @tab X
d698c5d3 350 @tab QuickTime fourcc 'alac'
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351@item Apple MACE 3 @tab @tab X
352@item Apple MACE 6 @tab @tab X
353@item ATRAC 3 @tab @tab X
354@item CD-ROM XA ADPCM @tab @tab X
bac4c85c 355@item Cin audio @tab @tab X
d698c5d3 356 @tab Codec used in Delphine Software International games.
16d81b27 357@item Creative ADPCM @tab @tab X
d698c5d3 358 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
16d81b27 359@item CRI ADX ADPCM @tab X @tab X
d698c5d3 360 @tab Used in Sega Dreamcast games.
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361@item DSP Group TrueSpeech @tab @tab X
362@item DTS Coherent Audio @tab @tab X
363@item Duck DK3 IMA ADPCM @tab @tab X
d698c5d3 364 @tab Used in some Sega Saturn console games.
16d81b27 365@item Duck DK4 IMA ADPCM @tab @tab X
d698c5d3 366 @tab Used in some Sega Saturn console games.
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367@item DV audio @tab @tab X
368@item Electronic Arts ADPCM @tab @tab X
d698c5d3 369 @tab Used in various EA titles.
44723c84 370@item Enhanced AC-3 @tab @tab X
9a584db4 371@item FLAC lossless audio @tab IX @tab X
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372@item G.726 ADPCM @tab X @tab X
373@item id RoQ DPCM @tab X @tab X
d698c5d3 374 @tab Used in Quake III, Jedi Knight 2, other computer games.
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375@item Intel Music Coder @tab @tab X
376@item Interplay MVE DPCM @tab @tab X
d698c5d3 377 @tab Used in various Interplay computer games.
16d81b27 378@item MAXIS EA ADPCM @tab @tab X
d698c5d3 379 @tab Used in Sim City 3000.
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380@item Microsoft ADPCM @tab X @tab X
381@item MLP/TrueHD @tab @tab X
d698c5d3 382 @tab Used in DVD-Audio and Blu-Ray discs.
16d81b27 383@item Monkey's Audio @tab @tab X
d698c5d3 384 @tab Only versions 3.97-3.99 are supported.
16d81b27 385@item MPEG audio layer 1/3 @tab X @tab IX
d698c5d3 386 @tab MP3 encoding is supported through the external library LAME.
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387@item MPEG audio layer 2 @tab IX @tab IX
388@item MS IMA ADPCM @tab X @tab X
389@item Musepack @tab @tab X
d698c5d3 390 @tab SV7 and SV8 are supported.
755ba886 391@item Nellymoser ASAO @tab X @tab X
16d81b27 392@item Qdesign QDM2 @tab @tab X
d698c5d3 393 @tab There are still some distortions.
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394@item QT IMA ADPCM @tab X @tab X
395@item RA144 @tab @tab X
d698c5d3 396 @tab Real 14400 bit/s codec
16d81b27 397@item RA288 @tab @tab X
d698c5d3 398 @tab Real 28800 bit/s codec
575a5bf2 399@item RADnet @tab IX @tab IX
a692130f 400 @tab Real low bitrate AC-3 codec
16d81b27 401@item Real COOK @tab @tab X
d698c5d3 402 @tab All versions except 5.1 are supported.
bac4c85c 403@item Shorten @tab @tab X
16d81b27 404@item Sierra Online DPCM @tab @tab X
d698c5d3 405 @tab Used in Sierra Online game audio files.
bac4c85c 406@item Smacker audio @tab @tab X
16d81b27 407@item SMJPEG IMA ADPCM @tab @tab X
d698c5d3 408 @tab Used in certain Loki game ports.
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409@item Sonic @tab X @tab X
410 @tab experimental codec
411@item Sonic lossless @tab X @tab X
412 @tab experimental codec
16d81b27 413@item THP ADPCM @tab @tab X
d698c5d3 414 @tab Used on the Nintendo GameCube.
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415@item True Audio (TTA) @tab @tab X
416@item Vorbis @tab X @tab X
bac4c85c 417@item WavPack @tab @tab X
16d81b27 418@item Westwood Studios IMA ADPCM @tab @tab X
d698c5d3 419 @tab Used in Westwood Studios games like Command and Conquer.
bac4c85c 420@item WMA v1/v2 @tab X @tab X
16d81b27 421@item Xan DPCM @tab @tab X
d698c5d3 422 @tab Used in Origin's Wing Commander IV AVI files.
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423@end multitable
424
425@code{X} means that encoding (resp. decoding) is supported.
426
427@code{I} means that an integer-only version is available, too (ensures high
428performance on systems without hardware floating point support).
429
430@chapter Platform Specific information
431
432@section BSD
433
434BSD make will not build FFmpeg, you need to install and use GNU Make
435(@file{gmake}).
436
437@section Windows
438
46a845d0 439To get help and instructions for building FFmpeg under Windows, check out
d0e1cd3d 440the FFmpeg Windows Help Forum at
ab5ce4ae 441@url{http://ffmpeg.arrozcru.org/}.
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442
443@subsection Native Windows compilation
444
c1989552 445FFmpeg can be built to run natively on Windows using the MinGW tools. Install
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446the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
447You can find detailed installation
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448instructions in the download section and the FAQ.
449
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450FFmpeg does not build out-of-the-box with the packages the automated MinGW
451installer provides. It also requires coreutils to be installed and many other
452packages updated to the latest version. The minimum version for some packages
453are listed below:
454
455@itemize
456@item bash 3.1
457@item msys-make 3.81-2 (note: not mingw32-make)
458@item w32api 3.12
459@item mingw-runtime 3.15
460@end itemize
461
c1989552 462Within the MSYS shell, configure and make with:
d0e1cd3d 463
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464@example
465./configure --enable-memalign-hack
466make
467make install
468@end example
d0e1cd3d 469
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470This will install @file{ffmpeg.exe} along with many other development files
471to @file{/usr/local}. You may specify another install path using the
472@code{--prefix} option in @file{configure}.
d0e1cd3d 473
c1989552 474Notes:
d0e1cd3d 475
c1989552 476@itemize
d0e1cd3d 477
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478@item In order to compile vhooks, you must have a POSIX-compliant libdl in
479your MinGW system. Get dlfcn-win32 from
480@url{http://code.google.com/p/dlfcn-win32}.
d0e1cd3d 481
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482@item In order to compile FFplay, you must have the MinGW development library
483of SDL. Get it from @url{http://www.libsdl.org}.
484Edit the @file{bin/sdl-config} script so that it points to the correct prefix
485where SDL was installed. Verify that @file{sdl-config} can be launched from
486the MSYS command line.
d0e1cd3d 487
d0e1cd3d 488@item By using @code{./configure --enable-shared} when configuring FFmpeg,
c1989552 489you can build libavutil, libavcodec and libavformat as DLLs.
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490
491@end itemize
492
c1989552 493@subsection Microsoft Visual C++ compatibility
d0e1cd3d 494
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495As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
496want to use the libav* libraries in your own applications, you can still
497compile those applications using MSVC++. But the libav* libraries you link
498to @emph{must} be built with MinGW. However, you will not be able to debug
499inside the libav* libraries, since MSVC++ does not recognize the debug
500symbols generated by GCC.
501We strongly recommend you to move over from MSVC++ to MinGW tools.
d0e1cd3d 502
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503This description of how to use the FFmpeg libraries with MSVC++ is based on
504Microsoft Visual C++ 2005 Express Edition. If you have a different version,
505you might have to modify the procedures slightly.
d0e1cd3d 506
c1989552 507@subsubsection Using static libraries
d0e1cd3d 508
c1989552 509Assuming you have just built and installed FFmpeg in @file{/usr/local}.
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510
511@enumerate
512
513@item Create a new console application ("File / New / Project") and then
514select "Win32 Console Application". On the appropriate page of the
515Application Wizard, uncheck the "Precompiled headers" option.
516
517@item Write the source code for your application, or, for testing, just
518copy the code from an existing sample application into the source file
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519that MSVC++ has already created for you. For example, you can copy
520@file{output_example.c} from the FFmpeg distribution.
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521
522@item Open the "Project / Properties" dialog box. In the "Configuration"
523combo box, select "All Configurations" so that the changes you make will
524affect both debug and release builds. In the tree view on the left hand
525side, select "C/C++ / General", then edit the "Additional Include
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526Directories" setting to contain the path where the FFmpeg includes were
527installed (i.e. @file{c:\msys\1.0\local\include}).
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528Do not add MinGW's include directory here, or the include files will
529conflict with MSVC's.
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530
531@item Still in the "Project / Properties" dialog box, select
532"Linker / General" from the tree view and edit the
533"Additional Library Directories" setting to contain the @file{lib}
534directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
535the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
536and the directory where MinGW's GCC libs are installed
537(i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
538"Linker / Input" from the tree view, and add the files @file{libavformat.a},
539@file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
540@file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
541to the end of "Additional Dependencies".
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542
543@item Now, select "C/C++ / Code Generation" from the tree view. Select
544"Debug" in the "Configuration" combo box. Make sure that "Runtime
545Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
546the "Configuration" combo box and make sure that "Runtime Library" is
547set to "Multi-threaded DLL".
548
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549@item Click "OK" to close the "Project / Properties" dialog box.
550
551@item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
552Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
553and install it in MSVC++'s include directory
554(i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
555
556@item MSVC++ also does not understand the @code{inline} keyword used by
557FFmpeg, so you must add this line before @code{#include}ing libav*:
558@example
559#define inline _inline
560@end example
561
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562@item Build your application, everything should work.
563
564@end enumerate
565
566@subsubsection Using shared libraries
567
568This is how to create DLL and LIB files that are compatible with MSVC++:
569
570@enumerate
571
572@item Add a call to @file{vcvars32.bat} (which sets up the environment
573variables for the Visual C++ tools) as the first line of @file{msys.bat}.
574The standard location for @file{vcvars32.bat} is
575@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
576and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
577If this corresponds to your setup, add the following line as the first line
578of @file{msys.bat}:
579
580@example
581call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
582@end example
583
584Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
585and run @file{c:\msys\1.0\msys.bat} from there.
586
587@item Within the MSYS shell, run @code{lib.exe}. If you get a help message
588from @file{Microsoft (R) Library Manager}, this means your environment
589variables are set up correctly, the @file{Microsoft (R) Library Manager}
590is on the path and will be used by FFmpeg to create
591MSVC++-compatible import libraries.
592
593@item Build FFmpeg with
594
595@example
596./configure --enable-shared --enable-memalign-hack
597make
598make install
599@end example
600
601Your install path (@file{/usr/local/} by default) should now have the
602necessary DLL and LIB files under the @file{bin} directory.
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603
604@end enumerate
605
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606To use those files with MSVC++, do the same as you would do with
607the static libraries, as described above. But in Step 4,
608you should only need to add the directory where the LIB files are installed
609(i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
610installed in the @file{bin} directory. And instead of adding @file{libxx.a}
611files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
612@file{avutil.lib}. There should be no need for @file{libmingwex.a},
613@file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
614statically linked into the DLLs. The @file{bin} directory contains a bunch
615of DLL files, but the ones that are actually used to run your application
616are the ones with a major version number in their filenames
617(i.e. @file{avcodec-51.dll}).
618
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619@subsection Cross compilation for Windows with Linux
620
621You must use the MinGW cross compilation tools available at
622@url{http://www.mingw.org/}.
623
624Then configure FFmpeg with the following options:
625@example
626./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
627@end example
628(you can change the cross-prefix according to the prefix chosen for the
629MinGW tools).
630
631Then you can easily test FFmpeg with Wine
632(@url{http://www.winehq.com/}).
633
634@subsection Compilation under Cygwin
635
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636The main issue with Cygwin is that newlib, its C library, does not
637contain llrint(). However, it is possible to leverage the
638implementation in MinGW.
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639
640Just install your Cygwin with all the "Base" packages, plus the
641following "Devel" ones:
642@example
29c3d42b 643binutils, gcc-core, make, subversion, mingw-runtime
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644@end example
645
646Do not install binutils-20060709-1 (they are buggy on shared builds);
647use binutils-20050610-1 instead.
648
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649Then create a small library that just contains llrint():
650
651@example
652ar x /usr/lib/mingw/libmingwex.a llrint.o
653ar cq /usr/local/lib/libllrint.a llrint.o
654@end example
655
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656Then run
657
658@example
29c3d42b 659./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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660@end example
661
662to make a static build or
663
664@example
29c3d42b 665./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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666@end example
667
668to build shared libraries.
669
670If you want to build FFmpeg with additional libraries, download Cygwin
671"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
672and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
673(@url{http://cygwinports.dotsrc.org/}).
674
675@subsection Crosscompilation for Windows under Cygwin
676
677With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
678
679Just install your Cygwin as explained before, plus these additional
680"Devel" packages:
681@example
682gcc-mingw-core, mingw-runtime, mingw-zlib
683@end example
684
685and add some special flags to your configure invocation.
686
687For a static build run
688@example
689./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
690@end example
691
692and for a build with shared libraries
693@example
694./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
695@end example
696
697@section BeOS
698
5f757b85 699BeOS support is broken in mysterious ways.
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701@section OS/2
702
703For information about compiling FFmpeg on OS/2 see
704@url{http://www.edm2.com/index.php/FFmpeg}.
705
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706@chapter Developers Guide
707
708@section API
709@itemize @bullet
710@item libavcodec is the library containing the codecs (both encoding and
711decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
712
713@item libavformat is the library containing the file format handling (mux and
714demux code for several formats). Look at @file{ffplay.c} to use it in a
715player. See @file{output_example.c} to use it to generate audio or video
716streams.
717
718@end itemize
719
720@section Integrating libavcodec or libavformat in your program
721
722You can integrate all the source code of the libraries to link them
723statically to avoid any version problem. All you need is to provide a
724'config.mak' and a 'config.h' in the parent directory. See the defines
725generated by ./configure to understand what is needed.
726
727You can use libavcodec or libavformat in your commercial program, but
728@emph{any patch you make must be published}. The best way to proceed is
729to send your patches to the FFmpeg mailing list.
730
731@node Coding Rules
732@section Coding Rules
733
734FFmpeg is programmed in the ISO C90 language with a few additional
735features from ISO C99, namely:
736@itemize @bullet
737@item
738the @samp{inline} keyword;
739@item
740@samp{//} comments;
741@item
742designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
743@item
744compound literals (@samp{x = (struct s) @{ 17, 23 @};})
745@end itemize
746
747These features are supported by all compilers we care about, so we will not
748accept patches to remove their use unless they absolutely do not impair
749clarity and performance.
750
751All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
752compiles with several other compilers, such as the Compaq ccc compiler
753or Sun Studio 9, and we would like to keep it that way unless it would
754be exceedingly involved. To ensure compatibility, please do not use any
755additional C99 features or GCC extensions. Especially watch out for:
756@itemize @bullet
757@item
758mixing statements and declarations;
759@item
760@samp{long long} (use @samp{int64_t} instead);
761@item
762@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
763@item
764GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
765@end itemize
766
767Indent size is 4.
768The presentation is the one specified by 'indent -i4 -kr -nut'.
769The TAB character is forbidden outside of Makefiles as is any
770form of trailing whitespace. Commits containing either will be
771rejected by the Subversion repository.
772
773The main priority in FFmpeg is simplicity and small code size in order to
774minimize the bug count.
775
776Comments: Use the JavaDoc/Doxygen
777format (see examples below) so that code documentation
778can be generated automatically. All nontrivial functions should have a comment
779above them explaining what the function does, even if it is just one sentence.
780All structures and their member variables should be documented, too.
781@example
782/**
783 * @@file mpeg.c
784 * MPEG codec.
785 * @@author ...
786 */
787
788/**
789 * Summary sentence.
790 * more text ...
791 * ...
792 */
793typedef struct Foobar@{
794 int var1; /**< var1 description */
795 int var2; ///< var2 description
796 /** var3 description */
797 int var3;
798@} Foobar;
799
800/**
801 * Summary sentence.
802 * more text ...
803 * ...
804 * @@param my_parameter description of my_parameter
805 * @@return return value description
806 */
807int myfunc(int my_parameter)
808...
809@end example
810
811fprintf and printf are forbidden in libavformat and libavcodec,
812please use av_log() instead.
813
814Casts should be used only when necessary. Unneeded parentheses
815should also be avoided if they don't make the code easier to understand.
816
817@section Development Policy
818
819@enumerate
820@item
821 Contributions should be licensed under the LGPL 2.1, including an
822 "or any later version" clause, or the MIT license. GPL 2 including
823 an "or any later version" clause is also acceptable, but LGPL is
824 preferred.
825@item
826 You must not commit code which breaks FFmpeg! (Meaning unfinished but
827 enabled code which breaks compilation or compiles but does not work or
828 breaks the regression tests)
829 You can commit unfinished stuff (for testing etc), but it must be disabled
830 (#ifdef etc) by default so it does not interfere with other developers'
831 work.
832@item
833 You do not have to over-test things. If it works for you, and you think it
834 should work for others, then commit. If your code has problems
835 (portability, triggers compiler bugs, unusual environment etc) they will be
836 reported and eventually fixed.
837@item
838 Do not commit unrelated changes together, split them into self-contained
839 pieces. Also do not forget that if part B depends on part A, but A does not
840 depend on B, then A can and should be committed first and separate from B.
841 Keeping changes well split into self-contained parts makes reviewing and
842 understanding them on the commit log mailing list easier. This also helps
843 in case of debugging later on.
844 Also if you have doubts about splitting or not splitting, do not hesitate to
845 ask/discuss it on the developer mailing list.
846@item
847 Do not change behavior of the program (renaming options etc) without
848 first discussing it on the ffmpeg-devel mailing list. Do not remove
849 functionality from the code. Just improve!
850
851 Note: Redundant code can be removed.
852@item
853 Do not commit changes to the build system (Makefiles, configure script)
854 which change behavior, defaults etc, without asking first. The same
855 applies to compiler warning fixes, trivial looking fixes and to code
856 maintained by other developers. We usually have a reason for doing things
857 the way we do. Send your changes as patches to the ffmpeg-devel mailing
858 list, and if the code maintainers say OK, you may commit. This does not
859 apply to files you wrote and/or maintain.
860@item
861 We refuse source indentation and other cosmetic changes if they are mixed
862 with functional changes, such commits will be rejected and removed. Every
863 developer has his own indentation style, you should not change it. Of course
864 if you (re)write something, you can use your own style, even though we would
865 prefer if the indentation throughout FFmpeg was consistent (Many projects
866 force a given indentation style - we do not.). If you really need to make
867 indentation changes (try to avoid this), separate them strictly from real
868 changes.
869
870 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
871 then either do NOT change the indentation of the inner part within (do not
872 move it to the right)! or do so in a separate commit
873@item
874 Always fill out the commit log message. Describe in a few lines what you
875 changed and why. You can refer to mailing list postings if you fix a
876 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
877@item
878 If you apply a patch by someone else, include the name and email address in
879 the log message. Since the ffmpeg-cvslog mailing list is publicly
880 archived you should add some SPAM protection to the email address. Send an
881 answer to ffmpeg-devel (or wherever you got the patch from) saying that
882 you applied the patch.
883@item
884 When applying patches that have been discussed (at length) on the mailing
885 list, reference the thread in the log message.
886@item
887 Do NOT commit to code actively maintained by others without permission.
888 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
889 timeframe (12h for build failures and security fixes, 3 days small changes,
890 1 week for big patches) then commit your patch if you think it is OK.
891 Also note, the maintainer can simply ask for more time to review!
892@item
893 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
894 are sent there and reviewed by all the other developers. Bugs and possible
895 improvements or general questions regarding commits are discussed there. We
896 expect you to react if problems with your code are uncovered.
897@item
898 Update the documentation if you change behavior or add features. If you are
899 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
900 maintainer(s) will review and commit your stuff.
901@item
902 Try to keep important discussions and requests (also) on the public
903 developer mailing list, so that all developers can benefit from them.
904@item
905 Never write to unallocated memory, never write over the end of arrays,
906 always check values read from some untrusted source before using them
907 as array index or other risky things.
908@item
909 Remember to check if you need to bump versions for the specific libav
910 parts (libavutil, libavcodec, libavformat) you are changing. You need
b98052d5 911 to change the version integer.
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912 Incrementing the first component means no backward compatibility to
913 previous versions (e.g. removal of a function from the public API).
914 Incrementing the second component means backward compatible change
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915 (e.g. addition of a function to the public API or extension of an
916 existing data structure).
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917 Incrementing the third component means a noteworthy binary compatible
918 change (e.g. encoder bug fix that matters for the decoder).
919@item
53407b64 920 Compiler warnings indicate potential bugs or code with bad style. If a type of
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921 warning always points to correct and clean code, that warning should
922 be disabled, not the code changed.
923 Thus the remaining warnings can either be bugs or correct code.
beaa4a91 924 If it is a bug, the bug has to be fixed. If it is not, the code should
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925 be changed to not generate a warning unless that causes a slowdown
926 or obfuscates the code.
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927@item
928 If you add a new file, give it a proper license header. Do not copy and
929 paste it from a random place, use an existing file as template.
930@end enumerate
931
932We think our rules are not too hard. If you have comments, contact us.
933
934Note, these rules are mostly borrowed from the MPlayer project.
935
936@section Submitting patches
937
938First, (@pxref{Coding Rules}) above if you did not yet.
939
940When you submit your patch, try to send a unified diff (diff '-up'
941option). We cannot read other diffs :-)
942
943Also please do not submit a patch which contains several unrelated changes.
944Split it into separate, self-contained pieces. This does not mean splitting
945file by file. Instead, make the patch as small as possible while still
946keeping it as a logical unit that contains an individual change, even
947if it spans multiple files. This makes reviewing your patches much easier
948for us and greatly increases your chances of getting your patch applied.
949
950Run the regression tests before submitting a patch so that you can
951verify that there are no big problems.
952
953Patches should be posted as base64 encoded attachments (or any other
954encoding which ensures that the patch will not be trashed during
955transmission) to the ffmpeg-devel mailing list, see
956@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
957
958It also helps quite a bit if you tell us what the patch does (for example
959'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
960and has no lrint()')
961
962Also please if you send several patches, send each patch as a separate mail,
963do not attach several unrelated patches to the same mail.
964
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965@section New codecs or formats checklist
966
967@enumerate
968@item
969 Did you use av_cold for codec initialization and close functions?
970@item
971 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
972 AVInputFormat/AVOutputFormat struct?
973@item
974 Did you bump the minor version number in @file{avcodec.h} or
975 @file{avformat.h}?
976@item
977 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
978@item
979 Did you add the CodecID to @file{avcodec.h}?
980@item
981 If it has a fourcc, did you add it to @file{libavformat/riff.c},
982 even if it is only a decoder?
983@item
984 Did you add a rule to compile the appropriate files in the Makefile?
985 Remember to do this even if you're just adding a format to a file that is
986 already being compiled by some other rule, like a raw demuxer.
987@item
988 Did you add an entry to the table of supported formats or codecs in the
989 documentation?
990@item
991 Did you add an entry in the Changelog?
992@item
993 If it depends on a parser or a library, did you add that dependency in
994 configure?
995@item
996 Did you "svn add" the appropriate files before commiting?
997@end enumerate
998
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999@section patch submission checklist
1000
1001@enumerate
1002@item
1003 Do the regression tests pass with the patch applied?
1004@item
1005 Is the patch a unified diff?
1006@item
1007 Is the patch against latest FFmpeg SVN?
1008@item
1009 Are you subscribed to ffmpeg-dev?
1010 (the list is subscribers only due to spam)
1011@item
1012 Have you checked that the changes are minimal, so that the same cannot be
1013 achieved with a smaller patch and/or simpler final code?
1014@item
1015 If the change is to speed critical code, did you benchmark it?
1016@item
1017 If you did any benchmarks, did you provide them in the mail?
1018@item
1019 Have you checked that the patch does not introduce buffer overflows or
1020 other security issues?
1021@item
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1022 If you add a new demuxer or decoder, have you checked that it does not
1023 crash with damaged input (see tools/trasher)?
1024@item
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1025 Is the patch created from the root of the source tree, so it can be
1026 applied with @code{patch -p0}?
1027@item
1028 Does the patch not mix functional and cosmetic changes?
1029@item
1030 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1031@item
1032 Is the patch attached to the email you send?
1033@item
1034 Is the mime type of the patch correct? It should be text/x-diff or
1035 text/x-patch or at least text/plain and not application/octet-stream.
1036@item
1037 If the patch fixes a bug, did you provide a verbose analysis of the bug?
1038@item
1039 If the patch fixes a bug, did you provide enough information, including
1040 a sample, so the bug can be reproduced and the fix can be verified?
1041 Note please do not attach samples >100k to mails but rather provide a
1042 URL, you can upload to ftp://upload.mplayerhq.hu
1043@item
1044 Did you provide a verbose summary about what the patch does change?
1045@item
1046 Did you provide a verbose explanation why it changes things like it does?
1047@item
1048 Did you provide a verbose summary of the user visible advantages and
1049 disadvantages if the patch is applied?
1050@item
1051 Did you provide an example so we can verify the new feature added by the
1052 patch easily?
1053@item
1054 If you added a new file, did you insert a license header? It should be
1055 taken from FFmpeg, not randomly copied and pasted from somewhere else.
1056@item
1057 You should maintain alphabetical order in alphabetically ordered lists as
1058 long as doing so does not break API/ABI compatibility.
1059@item
1060 Lines with similar content should be aligned vertically when doing so
1061 improves readability.
1062@item
1063 Did you provide a suggestion for a clear commit log message?
27250d20
MN
1064@item
1065 Did you test your decoder or demuxer against damaged data? If no, see
1066 tools/trasher and the noise bitstream filter. Your decoder or demuxer
fe74278f 1067 should not crash or end in a (near) infinite loop when fed damaged data.
d0e1cd3d
DB
1068@end enumerate
1069
1070@section Patch review process
1071
1072All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1073clear note that the patch is not for SVN.
1074Reviews and comments will be posted as replies to the patch on the
1075mailing list. The patch submitter then has to take care of every comment,
1076that can be by resubmitting a changed patch or by discussion. Resubmitted
1077patches will themselves be reviewed like any other patch. If at some point
1078a patch passes review with no comments then it is approved, that can for
1079simple and small patches happen immediately while large patches will generally
1080have to be changed and reviewed many times before they are approved.
1081After a patch is approved it will be committed to the repository.
1082
1083We will review all submitted patches, but sometimes we are quite busy so
1084especially for large patches this can take several weeks.
1085
1086When resubmitting patches, please do not make any significant changes
1087not related to the comments received during review. Such patches will
1088be rejected. Instead, submit significant changes or new features as
1089separate patches.
1090
1091@section Regression tests
1092
1093Before submitting a patch (or committing to the repository), you should at least
1094test that you did not break anything.
1095
1096The regression tests build a synthetic video stream and a synthetic
1097audio stream. These are then encoded and decoded with all codecs or
1098formats. The CRC (or MD5) of each generated file is recorded in a
1099result file. A 'diff' is launched to compare the reference results and
1100the result file.
1101
1102The regression tests then go on to test the FFserver code with a
1103limited set of streams. It is important that this step runs correctly
1104as well.
1105
1106Run 'make test' to test all the codecs and formats.
1107
1108Run 'make fulltest' to test all the codecs, formats and FFserver.
1109
1110[Of course, some patches may change the results of the regression tests. In
1111this case, the reference results of the regression tests shall be modified
1112accordingly].
1113
1114@bye