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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
c6b2dc34 45 @tab 4X Technologies format, used in some games.
39271be4 46@item Audio IFF (AIFF) @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.
39271be4 49@item 3GPP AMR @tab X @tab X
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50@item ASF @tab X @tab X
51@item AVI @tab X @tab X
39271be4 52@item AVISynth @tab @tab X
c6b2dc34 53@item AVS @tab @tab X
d698c5d3 54 @tab Multimedia format used by the Creature Shock game.
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55@item Beam Software SIFF @tab @tab X
56 @tab Audio and video format used in some games by Beam Software.
57@item Bethesda Softworks VID @tab @tab X
d698c5d3 58 @tab Used in some games from Bethesda Softworks.
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59@item Brute Force & Ignorance @tab @tab X
60 @tab Used in the game Flash Traffic: City of Angels.
61@item Interplay C93 @tab @tab X
d698c5d3 62 @tab Used in the game Cyberia from Interplay.
913c3e2c 63@item Delphine Software International CIN @tab @tab X
d698c5d3 64 @tab Multimedia format used by Delphine Software games.
39271be4 65@item CRC testing format @tab X @tab
913c3e2c 66@item Creative Voice @tab X @tab X
d698c5d3 67 @tab Created for the Sound Blaster Pro.
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68@item CRYO APC @tab @tab X
69 @tab Audio format used in some games by CRYO Interactive Entertainment.
39271be4 70@item D-Cinema audio @tab X @tab X
913c3e2c 71@item DV video @tab X @tab X
c6b2dc34 72@item DXA @tab @tab X
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73 @tab This format is used in the non-Windows version of the Feeble Files
74 game and different game cutscenes repacked for use with ScummVM.
39271be4 75@item Electronic Arts cdata @tab @tab X
c6b2dc34 76@item Electronic Arts Multimedia @tab @tab X
d698c5d3 77 @tab Used in various EA games; files have extensions like WVE and UV2.
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78@item FFM (FFserver live feed) @tab X @tab X
79@item Flash (SWF) @tab X @tab X
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80@item Flash 9 (AVM2) @tab X @tab X
81 @tab Only embedded audio is decoded.
82@item FLI/FLC/FLX animation @tab @tab X
d698c5d3 83 @tab .fli/.flc files
c6b2dc34 84@item FLV @tab X @tab X
d698c5d3 85 @tab Macromedia Flash video files
39271be4 86@item framecrc testing format @tab X @tab
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87@item FunCom ISS @tab @tab X
88 @tab Audio format used in various games from FunCom like The Longest Journey.
39271be4 89@item GIF Animation @tab X @tab
c6b2dc34 90@item GXF @tab X @tab X
d698c5d3 91 @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley
64c2f20a 92 playout servers.
76ec3939 93@item id Cinematic @tab @tab X
d698c5d3 94 @tab Used in Quake II.
76ec3939 95@item id RoQ @tab X @tab X
d698c5d3 96 @tab Used in Quake III, Jedi Knight 2, other computer games.
c6b2dc34 97@item IFF @tab @tab X
d698c5d3 98 @tab Interchange File Format
c6b2dc34 99@item Interplay MVE @tab @tab X
d698c5d3 100 @tab Format used in various Interplay computer games.
c6b2dc34 101@item LMLM4 @tab @tab X
d698c5d3 102 @tab Used by Linux Media Labs MPEG-4 PCI boards
64c2f20a 103@item Matroska @tab X @tab X
39271be4 104@item Matroska audio @tab X @tab
913c3e2c 105@item MAXIS XA @tab @tab X
d698c5d3 106 @tab Used in Sim City 3000; file extension .xa.
64c2f20a 107@item Monkey's Audio @tab @tab X
822cc8f7 108@item Motion Pixels MVI @tab @tab X
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109@item MOV/QuickTime/MP4 @tab X @tab X
110 @tab 3GP, 3GP2, PSP, iPod variants supported
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111@item MP2 @tab X @tab
112@item MP3 @tab X @tab
c6b2dc34 113@item MPEG audio @tab X @tab X
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114@item MPEG-1 System @tab X @tab X
115 @tab muxed audio and video, VCD format supported
116@item MPEG-PS (program stream) @tab X @tab X
117 @tab also known as @code{VOB} file, SVCD and DVD format supported
118@item MPEG-TS (transport stream) @tab X @tab X
d698c5d3 119 @tab also known as DVB Transport Stream
c6b2dc34 120@item MPEG-4 @tab X @tab X
d698c5d3 121 @tab MPEG-4 is a variant of QuickTime.
39271be4 122@item MIME multipart JPEG @tab X @tab
bac4c85c 123@item MSN TCP webcam @tab @tab X
d698c5d3 124 @tab Used by MSN Messenger webcam streams.
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125@item MTV @tab @tab X
126@item Musepack @tab @tab X
127@item Musepack SV8 @tab @tab X
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128@item Material eXchange Format (MXF) @tab X @tab X
129 @tab SMPTE 377M, used by D-Cinema, broadcast industry.
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130@item Material eXchange Format (MXF), D-10 Mapping @tab X @tab X
131 @tab SMPTE 386M, D-10/IMX Mapping.
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132@item NC camera feed @tab @tab X
133 @tab NC (AVIP NC4600) camera streams
134@item Nullsoft Streaming Video @tab @tab X
39271be4 135@item NuppelVideo @tab @tab X
c6b2dc34 136@item NUT @tab X @tab X
d698c5d3 137 @tab NUT Open Container Format
39271be4 138@item Ogg @tab X @tab X
913c3e2c 139@item TechnoTrend PVA @tab @tab X
d698c5d3 140 @tab Used by TechnoTrend DVB PCI boards.
43dedc1e 141@item raw ADTS (AAC) @tab X @tab X
76ec3939 142@item raw AC-3 @tab X @tab X
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143@item raw CRI ADX @tab X @tab X
144@item raw Dirac @tab X @tab X
145@item raw DNxHD @tab X @tab X
146@item raw DTS @tab X @tab X
147@item raw E-AC-3 @tab X @tab X
148@item raw FLAC @tab X @tab X
149@item raw GSM @tab @tab X
150@item raw H.261 @tab X @tab X
151@item raw H.263 @tab X @tab X
152@item raw H.264 @tab X @tab X
153@item raw Ingenient MJPEG @tab @tab X
76ec3939 154@item raw MJPEG @tab X @tab X
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155@item raw MLP @tab @tab X
156@item raw MPEG @tab @tab X
157@item raw MPEG-1 @tab @tab X
158@item raw MPEG-2 @tab @tab X
159@item raw MPEG-4 @tab X @tab X
160@item raw NULL @tab X @tab
81b55ee5 161@item raw video @tab X @tab X
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162@item raw id RoQ @tab X @tab
163@item raw Shorten @tab @tab X
164@item raw VC-1 @tab @tab X
165@item raw PCM A-law @tab X @tab X
166@item raw PCM mu-law @tab X @tab X
167@item raw PCM signed 8 bit @tab X @tab X
168@item raw PCM signed 16 bit big-endian @tab X @tab X
169@item raw PCM signed 16 bit little-endian @tab X @tab X
170@item raw PCM signed 24 bit big-endian @tab X @tab X
171@item raw PCM signed 24 bit little-endian @tab X @tab X
172@item raw PCM signed 32 bit big-endian @tab X @tab X
173@item raw PCM signed 32 bit little-endian @tab X @tab X
174@item raw PCM unsigned 8 bit @tab X @tab X
175@item raw PCM unsigned 16 bit big-endian @tab X @tab X
176@item raw PCM unsigned 16 bit little-endian @tab X @tab X
177@item raw PCM unsigned 24 bit big-endian @tab X @tab X
178@item raw PCM unsigned 24 bit little-endian @tab X @tab X
179@item raw PCM unsigned 32 bit big-endian @tab X @tab X
180@item raw PCM unsigned 32 bit little-endian @tab X @tab X
181@item raw PCM floating-point 32 bit big-endian @tab X @tab X
182@item raw PCM floating-point 32 bit little-endian @tab X @tab X
183@item raw PCM floating-point 64 bit big-endian @tab X @tab X
184@item raw PCM floating-point 64 bit little-endian @tab X @tab X
39271be4 185@item RDT @tab @tab X
913c3e2c 186@item REDCODE R3D @tab @tab X
7eb68edb 187 @tab File format used by RED Digital cameras, contains JPEG 2000 frames and PCM audio.
64c2f20a 188@item RealMedia @tab X @tab X
39271be4 189@item Redirector @tab @tab X
913c3e2c 190@item Renderware TeXture Dictionary @tab @tab X
c6b2dc34 191@item RL2 @tab @tab X
d698c5d3 192 @tab Audio and video format used in some games by Entertainment Software Partners.
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193@item RPL/ARMovie @tab @tab X
194@item RTP @tab @tab X
195@item RTSP @tab @tab X
196@item SDP @tab @tab X
c6b2dc34 197@item Sega FILM/CPK @tab @tab X
d698c5d3 198 @tab Used in many Sega Saturn console games.
913c3e2c 199@item Sierra SOL @tab @tab X
d698c5d3 200 @tab .sol files used in Sierra Online games.
c6b2dc34 201@item Sierra VMD @tab @tab X
d698c5d3 202 @tab Used in Sierra CD-ROM games.
c6b2dc34 203@item Smacker @tab @tab X
d698c5d3 204 @tab Multimedia format used by many games.
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205@item Sony OpenMG (OMA) @tab @tab X
206 @tab Audio format used in Sony Sonic Stage and Sony Vegas.
207@item Sony PlayStation STR @tab @tab X
64c2f20a 208@item SUN AU format @tab X @tab X
c6b2dc34 209@item THP @tab @tab X
d698c5d3 210 @tab Used on the Nintendo GameCube.
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211@item Tiertex Limited SEQ @tab @tab X
212 @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
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213@item True Audio @tab @tab X
214@item VC-1 test bitstream @tab X @tab X
c6b2dc34 215@item WAV @tab X @tab X
39271be4 216@item WavPack @tab @tab X
913c3e2c 217@item Wing Commander III movie @tab @tab X
d698c5d3 218 @tab Multimedia format used in Origin's Wing Commander III computer game.
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219@item Westwood Studios audio @tab @tab X
220 @tab Multimedia format used in Westwood Studios games.
221@item Westwood Studios VQA @tab @tab X
222 @tab Multimedia format used in Westwood Studios games.
39271be4 223@item YUV4MPEG pipe @tab X @tab X
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224@end multitable
225
226@code{X} means that encoding (resp. decoding) is supported.
227
228@section Image Formats
229
230FFmpeg can read and write images for each frame of a video sequence. The
231following image formats are supported:
232
233@multitable @columnfractions .4 .1 .1 .4
b3de4544 234@item Name @tab Encoding @tab Decoding @tab Comments
64c2f20a 235@item .Y.U.V @tab X @tab X @tab one raw file per component
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236@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
237@item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
9a77d59a 238@item JPEG 2000 @tab @tab E @tab decoding supported through external library libopenjpeg
d0e1cd3d 239@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
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240@item PCX @tab @tab X @tab PC Paintbrush
241@item PGM, PPM @tab X @tab X
d0e1cd3d 242@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
0a91f4ee 243@item PNG @tab X @tab X @tab 2/4 bpp not supported yet
d0e1cd3d 244@item PTX @tab @tab X @tab V.Flash PTX format
d1928ac1 245@item RAS @tab @tab X @tab Sun Rasterfile
3d172fb5 246@item SGI @tab X @tab X @tab SGI RGB image format
3d172fb5 247@item Targa @tab @tab X @tab Targa (.TGA) image format
64c2f20a 248@item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
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249@end multitable
250
251@code{X} means that encoding (resp. decoding) is supported.
252
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253@code{E} means that support is provided through an external library.
254
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255@section Video Codecs
256
257@multitable @columnfractions .4 .1 .1 .4
b3de4544 258@item Name @tab Encoding @tab Decoding @tab Comments
d66d8b83 259@item 4X Video @tab @tab X
d698c5d3 260 @tab Used in certain computer games.
913c3e2c 261@item American Laser Games MM @tab @tab X
d698c5d3 262 @tab Used in games like Mad Dog McCree.
d66d8b83 263@item AMV @tab @tab X
d698c5d3 264 @tab Used in Chinese MP3 players.
d66d8b83 265@item Apple Animation @tab X @tab X
d698c5d3 266 @tab fourcc: 'rle '
d66d8b83 267@item Apple Graphics @tab @tab X
d698c5d3 268 @tab fourcc: 'smc '
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269@item Apple MJPEG-B @tab @tab X
270@item Apple QuickDraw @tab @tab X
d698c5d3 271 @tab fourcc: qdrw
d66d8b83 272@item Apple Video @tab @tab X
d698c5d3 273 @tab fourcc: rpza
d66d8b83 274@item Asus v1 @tab X @tab X
d698c5d3 275 @tab fourcc: ASV1
d66d8b83 276@item Asus v2 @tab X @tab X
d698c5d3 277 @tab fourcc: ASV2
d66d8b83 278@item ATI VCR1 @tab @tab X
d698c5d3 279 @tab fourcc: VCR1
d66d8b83 280@item ATI VCR2 @tab @tab X
d698c5d3 281 @tab fourcc: VCR2
d66d8b83 282@item Autodesk RLE @tab @tab X
d698c5d3 283 @tab fourcc: AASC
d66d8b83 284@item AVID DNxHD @tab X @tab X
d698c5d3 285 @tab aka SMPTE VC3
bac4c85c 286@item AVS video @tab @tab X
d698c5d3 287 @tab Video encoding used by the Creature Shock game.
d66d8b83 288@item Bethsoft VID @tab @tab X
d698c5d3 289 @tab Used in some games from Bethesda Softworks.
bac4c85c 290@item C93 video @tab @tab X
d698c5d3 291 @tab Codec used in Cyberia game.
d66d8b83 292@item CamStudio @tab @tab X
d698c5d3 293 @tab fourcc: CSCD
bac4c85c 294@item Cin video @tab @tab X
d698c5d3 295 @tab Codec used in Delphine Software games.
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296@item Cinepak @tab @tab X
297@item Cirrus Logic AccuPak @tab @tab X
d698c5d3 298 @tab fourcc: CLJR
d66d8b83 299@item Creative YUV @tab @tab X
d698c5d3 300 @tab fourcc: CYUV
82ced5a9 301@item Dirac @tab E @tab E
360f980b 302 @tab supported through external libdirac/libschroedinger libraries
d66d8b83 303@item Duck TrueMotion v1 @tab @tab X
d698c5d3 304 @tab fourcc: DUCK
d66d8b83 305@item Duck TrueMotion v2 @tab @tab X
d698c5d3 306 @tab fourcc: TM20
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307@item DV @tab X @tab X
308@item DXA Video @tab @tab X
d698c5d3 309 @tab Codec originally used in Feeble Files game.
d66d8b83 310@item Electronic Arts CMV @tab @tab X
d698c5d3 311 @tab Used in NHL 95 game.
cfc78718 312@item Electronic Arts TGV @tab @tab X
42b30357 313@item Electronic Arts TGQ @tab @tab X
d8964f3a 314@item Electronic Arts TQI @tab @tab X
d66d8b83 315@item FFmpeg Video 1 @tab X @tab X
d698c5d3 316 @tab experimental lossless codec (fourcc: FFV1)
d66d8b83 317@item Flash Screen Video @tab X @tab X
d698c5d3 318 @tab fourcc: FSV1
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319@item FLIC video @tab @tab X
320@item FLV @tab X @tab X
d698c5d3 321 @tab Sorenson H.263 used in Flash
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322@item Fraps FPS1 @tab @tab X
323@item H.261 @tab X @tab X
324@item H.263(+) @tab X @tab X
d698c5d3 325 @tab also known as RealVideo 1.0
82ced5a9 326@item H.264 @tab E @tab X
360f980b 327 @tab encoding supported through external library libx264
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328@item HuffYUV @tab X @tab X
329@item IBM Ultimotion @tab @tab X
d698c5d3 330 @tab fourcc: ULTI
bac4c85c 331@item id Cinematic video @tab @tab X
d698c5d3 332 @tab Used in Quake II.
d66d8b83 333@item id RoQ @tab X @tab X
d698c5d3 334 @tab Used in Quake III, Jedi Knight 2, other computer games.
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335@item Intel Indeo 3 @tab @tab X
336@item Interplay Video @tab @tab X
d698c5d3 337 @tab Used in Interplay .MVE files.
d66d8b83 338@item JPEG-LS @tab X @tab X
d698c5d3 339 @tab fourcc: MJLS, lossless and near-lossless is supported.
d66d8b83 340@item KMVC @tab @tab X
d698c5d3 341 @tab Codec used in Worms games.
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342@item LOCO @tab @tab X
343@item lossless MJPEG @tab X @tab X
344@item Microsoft RLE @tab @tab X
345@item Microsoft Video-1 @tab @tab X
346@item Mimic @tab @tab X
d698c5d3 347 @tab Used in MSN Messenger Webcam streams.
d66d8b83 348@item Miro VideoXL @tab @tab X
d698c5d3 349 @tab fourcc: VIXL
d66d8b83 350@item MJPEG @tab X @tab X
822cc8f7 351@item Motion Pixels Video @tab @tab X
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352@item MPEG-1 @tab X @tab X
353@item MPEG-2 @tab X @tab X
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354@item MPEG-4 @tab X @tab X
355@item MSMPEG4 V1 @tab X @tab X
356@item MSMPEG4 V2 @tab X @tab X
357@item MSMPEG4 V3 @tab X @tab X
d66d8b83 358@item MSZH @tab @tab X
d698c5d3 359 @tab Part of LCL
d66d8b83 360@item On2 VP3 @tab @tab X
d698c5d3 361 @tab still experimental
d66d8b83 362@item On2 VP5 @tab @tab X
d698c5d3 363 @tab fourcc: VP50
d66d8b83 364@item On2 VP6 @tab @tab X
d698c5d3 365 @tab fourcc: VP60,VP61,VP62
d66d8b83 366@item planar RGB @tab @tab X
d698c5d3 367 @tab fourcc: 8BPS
d66d8b83 368@item QPEG @tab @tab X
d698c5d3 369 @tab fourccs: QPEG, Q1.0, Q1.1
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370@item RealVideo 1.0 @tab X @tab X
371@item RealVideo 2.0 @tab X @tab X
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372@item RealVideo 3.0 @tab @tab X
373 @tab still far from ideal
11c0f9ec 374@item RealVideo 4.0 @tab @tab X
d66d8b83 375@item Renderware TXD @tab @tab X
d698c5d3 376 @tab Texture dictionaries used by the Renderware Engine.
d66d8b83 377@item RTjpeg @tab @tab X
d698c5d3 378 @tab Video encoding used in NuppelVideo files.
bac4c85c 379@item Smacker video @tab @tab X
d698c5d3 380 @tab Video encoding used in Smacker.
d66d8b83 381@item Snow @tab X @tab X
d698c5d3 382 @tab experimental wavelet codec (fourcc: SNOW)
831ec935 383@item Sony PlayStation MDEC @tab @tab X
d66d8b83 384@item Sorenson Video 1 @tab X @tab X
d698c5d3 385 @tab fourcc: SVQ1
d66d8b83 386@item Sorenson Video 3 @tab @tab X
d698c5d3 387 @tab fourcc: SVQ3
d66d8b83 388@item Sunplus MJPEG @tab @tab X
d698c5d3 389 @tab fourcc: SP5X
d66d8b83 390@item TechSmith Camtasia @tab @tab X
d698c5d3 391 @tab fourcc: TSCC
82ced5a9 392@item Theora @tab E @tab X
360f980b 393 @tab encoding supported through external library libtheora
d66d8b83 394@item THP @tab @tab X
d698c5d3 395 @tab Used on the Nintendo GameCube.
bac4c85c 396@item Tiertex Seq video @tab @tab X
d698c5d3 397 @tab Codec used in DOS CD-ROM FlashBack game.
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398@item VC-1 @tab @tab X
399@item VMD Video @tab @tab X
d698c5d3 400 @tab Used in Sierra VMD files.
d66d8b83 401@item VMware Video @tab @tab X
d698c5d3 402 @tab Codec used in videos captured by VMware.
d0e1cd3d 403@item Westwood VQA @tab @tab X
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404@item Winnov WNV1 @tab @tab X
405@item WMV7 @tab X @tab X
406@item WMV8 @tab X @tab X
407@item WMV9 @tab @tab X
d698c5d3 408 @tab not completely working
d66d8b83 409@item Xan/WC3 @tab @tab X
d698c5d3 410 @tab Used in Wing Commander III .MVE files.
39271be4 411@item YAMAHA SMAF @tab X @tab X
d66d8b83 412@item ZLIB @tab X @tab X
d698c5d3 413 @tab part of LCL, encoder experimental
d66d8b83 414@item ZMBV @tab X @tab X
d698c5d3 415 @tab Encoder works only in PAL8.
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416@end multitable
417
418@code{X} means that encoding (resp. decoding) is supported.
419
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420@code{E} means that support is provided through an external library.
421
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422@section Audio Codecs
423
485ec4f1 424@multitable @columnfractions .4 .1 .1 .4
b3de4544 425@item Name @tab Encoding @tab Decoding @tab Comments
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426@item 4X IMA ADPCM @tab @tab X
427@item 8SVX audio @tab @tab X
82ced5a9 428@item AAC @tab E @tab X
360f980b 429 @tab encoding supported through external library libfaac
16d81b27 430@item AC-3 @tab IX @tab IX
82ced5a9 431@item AMR-NB @tab E @tab E
360f980b 432 @tab supported through external library libamrnb
82ced5a9 433@item AMR-WB @tab E @tab E
360f980b 434 @tab supported through external library libamrwb
16d81b27 435@item AMV IMA ADPCM @tab @tab X
d698c5d3 436 @tab Used in AMV files
833e90dd 437@item Apple lossless audio @tab X @tab X
d698c5d3 438 @tab QuickTime fourcc 'alac'
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439@item Apple MACE 3 @tab @tab X
440@item Apple MACE 6 @tab @tab X
441@item ATRAC 3 @tab @tab X
442@item CD-ROM XA ADPCM @tab @tab X
bac4c85c 443@item Cin audio @tab @tab X
d698c5d3 444 @tab Codec used in Delphine Software International games.
16d81b27 445@item Creative ADPCM @tab @tab X
d698c5d3 446 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
16d81b27 447@item CRI ADX ADPCM @tab X @tab X
d698c5d3 448 @tab Used in Sega Dreamcast games.
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449@item DSP Group TrueSpeech @tab @tab X
450@item DTS Coherent Audio @tab @tab X
451@item Duck DK3 IMA ADPCM @tab @tab X
d698c5d3 452 @tab Used in some Sega Saturn console games.
16d81b27 453@item Duck DK4 IMA ADPCM @tab @tab X
d698c5d3 454 @tab Used in some Sega Saturn console games.
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455@item DV audio @tab @tab X
456@item Electronic Arts ADPCM @tab @tab X
d698c5d3 457 @tab Used in various EA titles.
44723c84 458@item Enhanced AC-3 @tab @tab X
9a584db4 459@item FLAC lossless audio @tab IX @tab X
16d81b27 460@item G.726 ADPCM @tab X @tab X
82ced5a9 461@item GSM @tab E @tab E
3f33271a 462 @tab supported through external library libgsm
82ced5a9 463@item GSM_MS @tab E @tab E
3f33271a 464 @tab supported through external library libgsm
16d81b27 465@item id RoQ DPCM @tab X @tab X
d698c5d3 466 @tab Used in Quake III, Jedi Knight 2, other computer games.
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467@item Intel Music Coder @tab @tab X
468@item Interplay MVE DPCM @tab @tab X
d698c5d3 469 @tab Used in various Interplay computer games.
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470@item ISS IMA ADPCM @tab @tab X
471 @tab Used in FunCom games.
16d81b27 472@item MAXIS EA ADPCM @tab @tab X
d698c5d3 473 @tab Used in Sim City 3000.
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474@item Microsoft ADPCM @tab X @tab X
475@item MLP/TrueHD @tab @tab X
d698c5d3 476 @tab Used in DVD-Audio and Blu-Ray discs.
16d81b27 477@item Monkey's Audio @tab @tab X
d698c5d3 478 @tab Only versions 3.97-3.99 are supported.
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479@item MPEG audio layer 3 @tab E @tab IX
480 @tab encoding supported through external library LAME
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481@item MPEG audio layer 2 @tab IX @tab IX
482@item MS IMA ADPCM @tab X @tab X
483@item Musepack @tab @tab X
d698c5d3 484 @tab SV7 and SV8 are supported.
755ba886 485@item Nellymoser ASAO @tab X @tab X
73b458e3 486@item QCELP / PureVoice @tab @tab X
16d81b27 487@item Qdesign QDM2 @tab @tab X
d698c5d3 488 @tab There are still some distortions.
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489@item QT IMA ADPCM @tab X @tab X
490@item RA144 @tab @tab X
d698c5d3 491 @tab Real 14400 bit/s codec
16d81b27 492@item RA288 @tab @tab X
d698c5d3 493 @tab Real 28800 bit/s codec
575a5bf2 494@item RADnet @tab IX @tab IX
a692130f 495 @tab Real low bitrate AC-3 codec
16d81b27 496@item Real COOK @tab @tab X
d698c5d3 497 @tab All versions except 5.1 are supported.
bac4c85c 498@item Shorten @tab @tab X
16d81b27 499@item Sierra Online DPCM @tab @tab X
d698c5d3 500 @tab Used in Sierra Online game audio files.
bac4c85c 501@item Smacker audio @tab @tab X
16d81b27 502@item SMJPEG IMA ADPCM @tab @tab X
d698c5d3 503 @tab Used in certain Loki game ports.
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504@item Sonic @tab X @tab X
505 @tab experimental codec
506@item Sonic lossless @tab X @tab X
507 @tab experimental codec
82ced5a9 508@item Speex @tab @tab E
360f980b 509 @tab supported through external library libspeex
16d81b27 510@item THP ADPCM @tab @tab X
d698c5d3 511 @tab Used on the Nintendo GameCube.
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512@item True Audio (TTA) @tab @tab X
513@item Vorbis @tab X @tab X
bac4c85c 514@item WavPack @tab @tab X
16d81b27 515@item Westwood Studios IMA ADPCM @tab @tab X
d698c5d3 516 @tab Used in Westwood Studios games like Command and Conquer.
bac4c85c 517@item WMA v1/v2 @tab X @tab X
16d81b27 518@item Xan DPCM @tab @tab X
d698c5d3 519 @tab Used in Origin's Wing Commander IV AVI files.
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520@end multitable
521
522@code{X} means that encoding (resp. decoding) is supported.
523
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524@code{E} means that support is provided through an external library.
525
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526@code{I} means that an integer-only version is available, too (ensures high
527performance on systems without hardware floating point support).
528
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529@section Subtitle Formats
530
485ec4f1 531@multitable @columnfractions .4 .1 .1 .1 .1 .1
9afc2917 532@item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding
913c3e2c 533@item SSA/ASS @tab X @tab X
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534@item DVB @tab X @tab X @tab X @tab X
535@item DVD @tab X @tab X @tab X @tab X
536@item XSUB @tab @tab @tab @tab X
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537@end multitable
538
539@code{X} means that the feature is supported.
540
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541@section Network Protocols
542
543@multitable @columnfractions .4 .1 .1 .1 .1 .1
544@item Name @tab Support
545@item file @tab X
546@item Gopher @tab X
547@item HTTP @tab X
548@item pipe @tab X
549@item RTP @tab X
550@item TCP @tab X
551@item UDP @tab X
552@end multitable
553
554@code{X} means that the protocol is supported.
555
556
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557@chapter Platform Specific information
558
559@section BSD
560
561BSD make will not build FFmpeg, you need to install and use GNU Make
562(@file{gmake}).
563
564@section Windows
565
46a845d0 566To get help and instructions for building FFmpeg under Windows, check out
d0e1cd3d 567the FFmpeg Windows Help Forum at
ab5ce4ae 568@url{http://ffmpeg.arrozcru.org/}.
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569
570@subsection Native Windows compilation
571
c1989552 572FFmpeg can be built to run natively on Windows using the MinGW tools. Install
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573the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
574You can find detailed installation
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575instructions in the download section and the FAQ.
576
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577FFmpeg does not build out-of-the-box with the packages the automated MinGW
578installer provides. It also requires coreutils to be installed and many other
579packages updated to the latest version. The minimum version for some packages
580are listed below:
581
582@itemize
583@item bash 3.1
584@item msys-make 3.81-2 (note: not mingw32-make)
2014b51c 585@item w32api 3.13
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586@item mingw-runtime 3.15
587@end itemize
588
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589You will also need to pass @code{-fno-common} to the compiler to work around
590a GCC bug (see @url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216}).
591
c1989552 592Within the MSYS shell, configure and make with:
d0e1cd3d 593
c1989552 594@example
0f898714 595./configure --enable-memalign-hack --extra-cflags=-fno-common
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596make
597make install
598@end example
d0e1cd3d 599
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600This will install @file{ffmpeg.exe} along with many other development files
601to @file{/usr/local}. You may specify another install path using the
602@code{--prefix} option in @file{configure}.
d0e1cd3d 603
c1989552 604Notes:
d0e1cd3d 605
c1989552 606@itemize
d0e1cd3d 607
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608@item In order to compile vhooks, you must have a POSIX-compliant libdl in
609your MinGW system. Get dlfcn-win32 from
610@url{http://code.google.com/p/dlfcn-win32}.
d0e1cd3d 611
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612@item In order to compile FFplay, you must have the MinGW development library
613of SDL. Get it from @url{http://www.libsdl.org}.
614Edit the @file{bin/sdl-config} script so that it points to the correct prefix
615where SDL was installed. Verify that @file{sdl-config} can be launched from
616the MSYS command line.
d0e1cd3d 617
d0e1cd3d 618@item By using @code{./configure --enable-shared} when configuring FFmpeg,
c1989552 619you can build libavutil, libavcodec and libavformat as DLLs.
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620
621@end itemize
622
c1989552 623@subsection Microsoft Visual C++ compatibility
d0e1cd3d 624
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625As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
626want to use the libav* libraries in your own applications, you can still
627compile those applications using MSVC++. But the libav* libraries you link
628to @emph{must} be built with MinGW. However, you will not be able to debug
629inside the libav* libraries, since MSVC++ does not recognize the debug
630symbols generated by GCC.
631We strongly recommend you to move over from MSVC++ to MinGW tools.
d0e1cd3d 632
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633This description of how to use the FFmpeg libraries with MSVC++ is based on
634Microsoft Visual C++ 2005 Express Edition. If you have a different version,
635you might have to modify the procedures slightly.
d0e1cd3d 636
c1989552 637@subsubsection Using static libraries
d0e1cd3d 638
c1989552 639Assuming you have just built and installed FFmpeg in @file{/usr/local}.
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640
641@enumerate
642
643@item Create a new console application ("File / New / Project") and then
644select "Win32 Console Application". On the appropriate page of the
645Application Wizard, uncheck the "Precompiled headers" option.
646
647@item Write the source code for your application, or, for testing, just
648copy the code from an existing sample application into the source file
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649that MSVC++ has already created for you. For example, you can copy
650@file{output_example.c} from the FFmpeg distribution.
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651
652@item Open the "Project / Properties" dialog box. In the "Configuration"
653combo box, select "All Configurations" so that the changes you make will
654affect both debug and release builds. In the tree view on the left hand
655side, select "C/C++ / General", then edit the "Additional Include
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656Directories" setting to contain the path where the FFmpeg includes were
657installed (i.e. @file{c:\msys\1.0\local\include}).
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658Do not add MinGW's include directory here, or the include files will
659conflict with MSVC's.
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660
661@item Still in the "Project / Properties" dialog box, select
662"Linker / General" from the tree view and edit the
663"Additional Library Directories" setting to contain the @file{lib}
664directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
665the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
666and the directory where MinGW's GCC libs are installed
667(i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
668"Linker / Input" from the tree view, and add the files @file{libavformat.a},
669@file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
670@file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
671to the end of "Additional Dependencies".
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672
673@item Now, select "C/C++ / Code Generation" from the tree view. Select
674"Debug" in the "Configuration" combo box. Make sure that "Runtime
675Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
676the "Configuration" combo box and make sure that "Runtime Library" is
677set to "Multi-threaded DLL".
678
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679@item Click "OK" to close the "Project / Properties" dialog box.
680
681@item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
682Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
683and install it in MSVC++'s include directory
684(i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
685
686@item MSVC++ also does not understand the @code{inline} keyword used by
687FFmpeg, so you must add this line before @code{#include}ing libav*:
688@example
689#define inline _inline
690@end example
691
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692@item Build your application, everything should work.
693
694@end enumerate
695
696@subsubsection Using shared libraries
697
698This is how to create DLL and LIB files that are compatible with MSVC++:
699
700@enumerate
701
702@item Add a call to @file{vcvars32.bat} (which sets up the environment
703variables for the Visual C++ tools) as the first line of @file{msys.bat}.
704The standard location for @file{vcvars32.bat} is
705@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
706and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
707If this corresponds to your setup, add the following line as the first line
708of @file{msys.bat}:
709
710@example
711call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
712@end example
713
714Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
715and run @file{c:\msys\1.0\msys.bat} from there.
716
717@item Within the MSYS shell, run @code{lib.exe}. If you get a help message
718from @file{Microsoft (R) Library Manager}, this means your environment
719variables are set up correctly, the @file{Microsoft (R) Library Manager}
720is on the path and will be used by FFmpeg to create
721MSVC++-compatible import libraries.
722
723@item Build FFmpeg with
724
725@example
726./configure --enable-shared --enable-memalign-hack
727make
728make install
729@end example
730
731Your install path (@file{/usr/local/} by default) should now have the
732necessary DLL and LIB files under the @file{bin} directory.
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733
734@end enumerate
735
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736To use those files with MSVC++, do the same as you would do with
737the static libraries, as described above. But in Step 4,
738you should only need to add the directory where the LIB files are installed
739(i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
740installed in the @file{bin} directory. And instead of adding @file{libxx.a}
741files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
742@file{avutil.lib}. There should be no need for @file{libmingwex.a},
743@file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
744statically linked into the DLLs. The @file{bin} directory contains a bunch
745of DLL files, but the ones that are actually used to run your application
746are the ones with a major version number in their filenames
747(i.e. @file{avcodec-51.dll}).
748
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749@subsection Cross compilation for Windows with Linux
750
751You must use the MinGW cross compilation tools available at
752@url{http://www.mingw.org/}.
753
754Then configure FFmpeg with the following options:
755@example
756./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
757@end example
758(you can change the cross-prefix according to the prefix chosen for the
759MinGW tools).
760
761Then you can easily test FFmpeg with Wine
762(@url{http://www.winehq.com/}).
763
764@subsection Compilation under Cygwin
765
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766The main issue with the 1.5.x Cygwin versions is that newlib, its C library,
767does not contain llrint(). You need to upgrade to the unstable 1.7.x versions,
768or leverage the implementation in MinGW (as explained below).
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769
770Just install your Cygwin with all the "Base" packages, plus the
771following "Devel" ones:
772@example
f496ab12 773binutils, gcc-core, make, subversion, mingw-runtime, diffutils
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774@end example
775
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776The experimental gcc4 package is still buggy, hence please
777use the official gcc 3.4.4 or a 4.2.x compiled from source by yourself.
778
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779Install the current binutils-20080624-2 as they work fine (the old
780binutils-20060709-1 proved buggy on shared builds).
d0e1cd3d 781
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782Then create a small library that just contains llrint():
783
784@example
785ar x /usr/lib/mingw/libmingwex.a llrint.o
786ar cq /usr/local/lib/libllrint.a llrint.o
787@end example
788
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789Then run
790
791@example
29c3d42b 792./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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793@end example
794
795to make a static build or
796
797@example
29c3d42b 798./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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799@end example
800
801to build shared libraries.
802
803If you want to build FFmpeg with additional libraries, download Cygwin
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804"Devel" packages for Ogg and Vorbis from any Cygwin packages repository:
805@example
806libogg-devel, libvorbis-devel
807@end example
808
809These library packages are only available from Cygwin Ports
be8497b0 810(@url{http://sourceware.org/cygwinports/}) :
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811
812@example
813yasm, libSDL-devel, libdirac-devel, libfaac-devel, libfaad-devel, libgsm-devel,
814libmp3lame-devel, libschroedinger1.0-devel, speex-devel, libtheora-devel,
815libxvidcore-devel
816@end example
817
818The recommendation for libnut and x264 is to build them from source by
819yourself, as they evolve too quickly for Cygwin Ports to be up to date.
d0e1cd3d 820
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821Cygwin 1.7.x has IPv6 support. You can add IPv6 to Cygwin 1.5.x by means
822of the @code{libgetaddrinfo-devel} package, available at Cygwin Ports.
823
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824@subsection Crosscompilation for Windows under Cygwin
825
826With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
827
828Just install your Cygwin as explained before, plus these additional
829"Devel" packages:
830@example
831gcc-mingw-core, mingw-runtime, mingw-zlib
832@end example
833
834and add some special flags to your configure invocation.
835
836For a static build run
837@example
838./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
839@end example
840
841and for a build with shared libraries
842@example
843./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
844@end example
845
846@section BeOS
847
5f757b85 848BeOS support is broken in mysterious ways.
d0e1cd3d 849
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850@section OS/2
851
852For information about compiling FFmpeg on OS/2 see
853@url{http://www.edm2.com/index.php/FFmpeg}.
854
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855@chapter Developers Guide
856
857@section API
858@itemize @bullet
859@item libavcodec is the library containing the codecs (both encoding and
860decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
861
862@item libavformat is the library containing the file format handling (mux and
863demux code for several formats). Look at @file{ffplay.c} to use it in a
864player. See @file{output_example.c} to use it to generate audio or video
865streams.
866
867@end itemize
868
869@section Integrating libavcodec or libavformat in your program
870
871You can integrate all the source code of the libraries to link them
872statically to avoid any version problem. All you need is to provide a
873'config.mak' and a 'config.h' in the parent directory. See the defines
874generated by ./configure to understand what is needed.
875
876You can use libavcodec or libavformat in your commercial program, but
877@emph{any patch you make must be published}. The best way to proceed is
878to send your patches to the FFmpeg mailing list.
879
880@node Coding Rules
881@section Coding Rules
882
883FFmpeg is programmed in the ISO C90 language with a few additional
884features from ISO C99, namely:
885@itemize @bullet
886@item
887the @samp{inline} keyword;
888@item
889@samp{//} comments;
890@item
891designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
892@item
893compound literals (@samp{x = (struct s) @{ 17, 23 @};})
894@end itemize
895
896These features are supported by all compilers we care about, so we will not
897accept patches to remove their use unless they absolutely do not impair
898clarity and performance.
899
900All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
901compiles with several other compilers, such as the Compaq ccc compiler
902or Sun Studio 9, and we would like to keep it that way unless it would
903be exceedingly involved. To ensure compatibility, please do not use any
904additional C99 features or GCC extensions. Especially watch out for:
905@itemize @bullet
906@item
907mixing statements and declarations;
908@item
909@samp{long long} (use @samp{int64_t} instead);
910@item
911@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
912@item
913GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
914@end itemize
915
916Indent size is 4.
917The presentation is the one specified by 'indent -i4 -kr -nut'.
918The TAB character is forbidden outside of Makefiles as is any
919form of trailing whitespace. Commits containing either will be
920rejected by the Subversion repository.
921
922The main priority in FFmpeg is simplicity and small code size in order to
923minimize the bug count.
924
925Comments: Use the JavaDoc/Doxygen
926format (see examples below) so that code documentation
927can be generated automatically. All nontrivial functions should have a comment
928above them explaining what the function does, even if it is just one sentence.
929All structures and their member variables should be documented, too.
930@example
931/**
932 * @@file mpeg.c
933 * MPEG codec.
934 * @@author ...
935 */
936
937/**
938 * Summary sentence.
939 * more text ...
940 * ...
941 */
942typedef struct Foobar@{
943 int var1; /**< var1 description */
944 int var2; ///< var2 description
945 /** var3 description */
946 int var3;
947@} Foobar;
948
949/**
950 * Summary sentence.
951 * more text ...
952 * ...
953 * @@param my_parameter description of my_parameter
954 * @@return return value description
955 */
956int myfunc(int my_parameter)
957...
958@end example
959
960fprintf and printf are forbidden in libavformat and libavcodec,
961please use av_log() instead.
962
963Casts should be used only when necessary. Unneeded parentheses
964should also be avoided if they don't make the code easier to understand.
965
966@section Development Policy
967
968@enumerate
969@item
970 Contributions should be licensed under the LGPL 2.1, including an
971 "or any later version" clause, or the MIT license. GPL 2 including
972 an "or any later version" clause is also acceptable, but LGPL is
973 preferred.
974@item
975 You must not commit code which breaks FFmpeg! (Meaning unfinished but
976 enabled code which breaks compilation or compiles but does not work or
977 breaks the regression tests)
978 You can commit unfinished stuff (for testing etc), but it must be disabled
979 (#ifdef etc) by default so it does not interfere with other developers'
980 work.
981@item
982 You do not have to over-test things. If it works for you, and you think it
983 should work for others, then commit. If your code has problems
984 (portability, triggers compiler bugs, unusual environment etc) they will be
985 reported and eventually fixed.
986@item
987 Do not commit unrelated changes together, split them into self-contained
988 pieces. Also do not forget that if part B depends on part A, but A does not
989 depend on B, then A can and should be committed first and separate from B.
990 Keeping changes well split into self-contained parts makes reviewing and
991 understanding them on the commit log mailing list easier. This also helps
992 in case of debugging later on.
993 Also if you have doubts about splitting or not splitting, do not hesitate to
994 ask/discuss it on the developer mailing list.
995@item
996 Do not change behavior of the program (renaming options etc) without
997 first discussing it on the ffmpeg-devel mailing list. Do not remove
998 functionality from the code. Just improve!
999
1000 Note: Redundant code can be removed.
1001@item
1002 Do not commit changes to the build system (Makefiles, configure script)
1003 which change behavior, defaults etc, without asking first. The same
1004 applies to compiler warning fixes, trivial looking fixes and to code
1005 maintained by other developers. We usually have a reason for doing things
1006 the way we do. Send your changes as patches to the ffmpeg-devel mailing
1007 list, and if the code maintainers say OK, you may commit. This does not
1008 apply to files you wrote and/or maintain.
1009@item
1010 We refuse source indentation and other cosmetic changes if they are mixed
1011 with functional changes, such commits will be rejected and removed. Every
1012 developer has his own indentation style, you should not change it. Of course
1013 if you (re)write something, you can use your own style, even though we would
1014 prefer if the indentation throughout FFmpeg was consistent (Many projects
1015 force a given indentation style - we do not.). If you really need to make
1016 indentation changes (try to avoid this), separate them strictly from real
1017 changes.
1018
1019 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1020 then either do NOT change the indentation of the inner part within (do not
1021 move it to the right)! or do so in a separate commit
1022@item
1023 Always fill out the commit log message. Describe in a few lines what you
1024 changed and why. You can refer to mailing list postings if you fix a
1025 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1026@item
1027 If you apply a patch by someone else, include the name and email address in
1028 the log message. Since the ffmpeg-cvslog mailing list is publicly
1029 archived you should add some SPAM protection to the email address. Send an
1030 answer to ffmpeg-devel (or wherever you got the patch from) saying that
1031 you applied the patch.
1032@item
1033 When applying patches that have been discussed (at length) on the mailing
1034 list, reference the thread in the log message.
1035@item
1036 Do NOT commit to code actively maintained by others without permission.
1037 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
1038 timeframe (12h for build failures and security fixes, 3 days small changes,
1039 1 week for big patches) then commit your patch if you think it is OK.
1040 Also note, the maintainer can simply ask for more time to review!
1041@item
1042 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1043 are sent there and reviewed by all the other developers. Bugs and possible
1044 improvements or general questions regarding commits are discussed there. We
1045 expect you to react if problems with your code are uncovered.
1046@item
1047 Update the documentation if you change behavior or add features. If you are
1048 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1049 maintainer(s) will review and commit your stuff.
1050@item
1051 Try to keep important discussions and requests (also) on the public
1052 developer mailing list, so that all developers can benefit from them.
1053@item
1054 Never write to unallocated memory, never write over the end of arrays,
1055 always check values read from some untrusted source before using them
1056 as array index or other risky things.
1057@item
1058 Remember to check if you need to bump versions for the specific libav
1059 parts (libavutil, libavcodec, libavformat) you are changing. You need
b98052d5 1060 to change the version integer.
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DB
1061 Incrementing the first component means no backward compatibility to
1062 previous versions (e.g. removal of a function from the public API).
1063 Incrementing the second component means backward compatible change
b98052d5
PR
1064 (e.g. addition of a function to the public API or extension of an
1065 existing data structure).
d0e1cd3d
DB
1066 Incrementing the third component means a noteworthy binary compatible
1067 change (e.g. encoder bug fix that matters for the decoder).
1068@item
53407b64 1069 Compiler warnings indicate potential bugs or code with bad style. If a type of
9908c1a8
DB
1070 warning always points to correct and clean code, that warning should
1071 be disabled, not the code changed.
1072 Thus the remaining warnings can either be bugs or correct code.
beaa4a91 1073 If it is a bug, the bug has to be fixed. If it is not, the code should
9908c1a8
DB
1074 be changed to not generate a warning unless that causes a slowdown
1075 or obfuscates the code.
d0e1cd3d
DB
1076@item
1077 If you add a new file, give it a proper license header. Do not copy and
1078 paste it from a random place, use an existing file as template.
1079@end enumerate
1080
1081We think our rules are not too hard. If you have comments, contact us.
1082
1083Note, these rules are mostly borrowed from the MPlayer project.
1084
1085@section Submitting patches
1086
1087First, (@pxref{Coding Rules}) above if you did not yet.
1088
1089When you submit your patch, try to send a unified diff (diff '-up'
1090option). We cannot read other diffs :-)
1091
1092Also please do not submit a patch which contains several unrelated changes.
1093Split it into separate, self-contained pieces. This does not mean splitting
1094file by file. Instead, make the patch as small as possible while still
1095keeping it as a logical unit that contains an individual change, even
1096if it spans multiple files. This makes reviewing your patches much easier
1097for us and greatly increases your chances of getting your patch applied.
1098
1099Run the regression tests before submitting a patch so that you can
1100verify that there are no big problems.
1101
1102Patches should be posted as base64 encoded attachments (or any other
1103encoding which ensures that the patch will not be trashed during
1104transmission) to the ffmpeg-devel mailing list, see
1105@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1106
1107It also helps quite a bit if you tell us what the patch does (for example
1108'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1109and has no lrint()')
1110
1111Also please if you send several patches, send each patch as a separate mail,
1112do not attach several unrelated patches to the same mail.
1113
28ce1839
RP
1114@section New codecs or formats checklist
1115
1116@enumerate
1117@item
1118 Did you use av_cold for codec initialization and close functions?
1119@item
1120 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
1121 AVInputFormat/AVOutputFormat struct?
1122@item
1123 Did you bump the minor version number in @file{avcodec.h} or
1124 @file{avformat.h}?
1125@item
1126 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
1127@item
1128 Did you add the CodecID to @file{avcodec.h}?
1129@item
1130 If it has a fourcc, did you add it to @file{libavformat/riff.c},
1131 even if it is only a decoder?
1132@item
1133 Did you add a rule to compile the appropriate files in the Makefile?
1134 Remember to do this even if you're just adding a format to a file that is
1135 already being compiled by some other rule, like a raw demuxer.
1136@item
1137 Did you add an entry to the table of supported formats or codecs in the
1138 documentation?
1139@item
1140 Did you add an entry in the Changelog?
1141@item
1142 If it depends on a parser or a library, did you add that dependency in
1143 configure?
1144@item
1145 Did you "svn add" the appropriate files before commiting?
1146@end enumerate
1147
d0e1cd3d
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1148@section patch submission checklist
1149
1150@enumerate
1151@item
1152 Do the regression tests pass with the patch applied?
1153@item
2cdba8bf
DB
1154 Does @code{make checkheaders} pass with the patch applied?
1155@item
d0e1cd3d
DB
1156 Is the patch a unified diff?
1157@item
1158 Is the patch against latest FFmpeg SVN?
1159@item
1160 Are you subscribed to ffmpeg-dev?
1161 (the list is subscribers only due to spam)
1162@item
1163 Have you checked that the changes are minimal, so that the same cannot be
1164 achieved with a smaller patch and/or simpler final code?
1165@item
1166 If the change is to speed critical code, did you benchmark it?
1167@item
1168 If you did any benchmarks, did you provide them in the mail?
1169@item
1170 Have you checked that the patch does not introduce buffer overflows or
1171 other security issues?
1172@item
63d247ea
DB
1173 Did you test your decoder or demuxer against damaged data? If no, see
1174 tools/trasher and the noise bitstream filter. Your decoder or demuxer
1175 should not crash or end in a (near) infinite loop when fed damaged data.
b885e0db 1176@item
d0e1cd3d
DB
1177 Is the patch created from the root of the source tree, so it can be
1178 applied with @code{patch -p0}?
1179@item
1180 Does the patch not mix functional and cosmetic changes?
1181@item
1182 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1183@item
1184 Is the patch attached to the email you send?
1185@item
1186 Is the mime type of the patch correct? It should be text/x-diff or
1187 text/x-patch or at least text/plain and not application/octet-stream.
1188@item
1189 If the patch fixes a bug, did you provide a verbose analysis of the bug?
1190@item
1191 If the patch fixes a bug, did you provide enough information, including
1192 a sample, so the bug can be reproduced and the fix can be verified?
1193 Note please do not attach samples >100k to mails but rather provide a
0fa5f24c 1194 URL, you can upload to ftp://upload.ffmpeg.org
d0e1cd3d
DB
1195@item
1196 Did you provide a verbose summary about what the patch does change?
1197@item
1198 Did you provide a verbose explanation why it changes things like it does?
1199@item
1200 Did you provide a verbose summary of the user visible advantages and
1201 disadvantages if the patch is applied?
1202@item
1203 Did you provide an example so we can verify the new feature added by the
1204 patch easily?
1205@item
1206 If you added a new file, did you insert a license header? It should be
1207 taken from FFmpeg, not randomly copied and pasted from somewhere else.
1208@item
1209 You should maintain alphabetical order in alphabetically ordered lists as
1210 long as doing so does not break API/ABI compatibility.
1211@item
1212 Lines with similar content should be aligned vertically when doing so
1213 improves readability.
1214@item
1215 Did you provide a suggestion for a clear commit log message?
1216@end enumerate
1217
1218@section Patch review process
1219
1220All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1221clear note that the patch is not for SVN.
1222Reviews and comments will be posted as replies to the patch on the
1223mailing list. The patch submitter then has to take care of every comment,
1224that can be by resubmitting a changed patch or by discussion. Resubmitted
1225patches will themselves be reviewed like any other patch. If at some point
1226a patch passes review with no comments then it is approved, that can for
1227simple and small patches happen immediately while large patches will generally
1228have to be changed and reviewed many times before they are approved.
1229After a patch is approved it will be committed to the repository.
1230
1231We will review all submitted patches, but sometimes we are quite busy so
1232especially for large patches this can take several weeks.
1233
1234When resubmitting patches, please do not make any significant changes
1235not related to the comments received during review. Such patches will
1236be rejected. Instead, submit significant changes or new features as
1237separate patches.
1238
1239@section Regression tests
1240
1241Before submitting a patch (or committing to the repository), you should at least
1242test that you did not break anything.
1243
1244The regression tests build a synthetic video stream and a synthetic
1245audio stream. These are then encoded and decoded with all codecs or
1246formats. The CRC (or MD5) of each generated file is recorded in a
1247result file. A 'diff' is launched to compare the reference results and
1248the result file.
1249
1250The regression tests then go on to test the FFserver code with a
1251limited set of streams. It is important that this step runs correctly
1252as well.
1253
1254Run 'make test' to test all the codecs and formats.
1255
1256Run 'make fulltest' to test all the codecs, formats and FFserver.
1257
1258[Of course, some patches may change the results of the regression tests. In
1259this case, the reference results of the regression tests shall be modified
1260accordingly].
1261
1262@bye