add some missing codecs and update some names to match AVCodec.long_name
[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
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
adc5abf7 143@item raw Chinese AVS video @tab @tab X
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144@item raw CRI ADX @tab X @tab X
145@item raw Dirac @tab X @tab X
146@item raw DNxHD @tab X @tab X
147@item raw DTS @tab X @tab X
148@item raw E-AC-3 @tab X @tab X
149@item raw FLAC @tab X @tab X
150@item raw GSM @tab @tab X
151@item raw H.261 @tab X @tab X
152@item raw H.263 @tab X @tab X
153@item raw H.264 @tab X @tab X
154@item raw Ingenient MJPEG @tab @tab X
76ec3939 155@item raw MJPEG @tab X @tab X
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156@item raw MLP @tab @tab X
157@item raw MPEG @tab @tab X
158@item raw MPEG-1 @tab @tab X
159@item raw MPEG-2 @tab @tab X
160@item raw MPEG-4 @tab X @tab X
161@item raw NULL @tab X @tab
81b55ee5 162@item raw video @tab X @tab X
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163@item raw id RoQ @tab X @tab
164@item raw Shorten @tab @tab X
165@item raw VC-1 @tab @tab X
166@item raw PCM A-law @tab X @tab X
167@item raw PCM mu-law @tab X @tab X
168@item raw PCM signed 8 bit @tab X @tab X
169@item raw PCM signed 16 bit big-endian @tab X @tab X
170@item raw PCM signed 16 bit little-endian @tab X @tab X
171@item raw PCM signed 24 bit big-endian @tab X @tab X
172@item raw PCM signed 24 bit little-endian @tab X @tab X
173@item raw PCM signed 32 bit big-endian @tab X @tab X
174@item raw PCM signed 32 bit little-endian @tab X @tab X
175@item raw PCM unsigned 8 bit @tab X @tab X
176@item raw PCM unsigned 16 bit big-endian @tab X @tab X
177@item raw PCM unsigned 16 bit little-endian @tab X @tab X
178@item raw PCM unsigned 24 bit big-endian @tab X @tab X
179@item raw PCM unsigned 24 bit little-endian @tab X @tab X
180@item raw PCM unsigned 32 bit big-endian @tab X @tab X
181@item raw PCM unsigned 32 bit little-endian @tab X @tab X
182@item raw PCM floating-point 32 bit big-endian @tab X @tab X
183@item raw PCM floating-point 32 bit little-endian @tab X @tab X
184@item raw PCM floating-point 64 bit big-endian @tab X @tab X
185@item raw PCM floating-point 64 bit little-endian @tab X @tab X
39271be4 186@item RDT @tab @tab X
913c3e2c 187@item REDCODE R3D @tab @tab X
7eb68edb 188 @tab File format used by RED Digital cameras, contains JPEG 2000 frames and PCM audio.
64c2f20a 189@item RealMedia @tab X @tab X
39271be4 190@item Redirector @tab @tab X
913c3e2c 191@item Renderware TeXture Dictionary @tab @tab X
c6b2dc34 192@item RL2 @tab @tab X
d698c5d3 193 @tab Audio and video format used in some games by Entertainment Software Partners.
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194@item RPL/ARMovie @tab @tab X
195@item RTP @tab @tab X
196@item RTSP @tab @tab X
197@item SDP @tab @tab X
c6b2dc34 198@item Sega FILM/CPK @tab @tab X
d698c5d3 199 @tab Used in many Sega Saturn console games.
913c3e2c 200@item Sierra SOL @tab @tab X
d698c5d3 201 @tab .sol files used in Sierra Online games.
c6b2dc34 202@item Sierra VMD @tab @tab X
d698c5d3 203 @tab Used in Sierra CD-ROM games.
c6b2dc34 204@item Smacker @tab @tab X
d698c5d3 205 @tab Multimedia format used by many games.
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206@item Sony OpenMG (OMA) @tab @tab X
207 @tab Audio format used in Sony Sonic Stage and Sony Vegas.
208@item Sony PlayStation STR @tab @tab X
64c2f20a 209@item SUN AU format @tab X @tab X
c6b2dc34 210@item THP @tab @tab X
d698c5d3 211 @tab Used on the Nintendo GameCube.
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212@item Tiertex Limited SEQ @tab @tab X
213 @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
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214@item True Audio @tab @tab X
215@item VC-1 test bitstream @tab X @tab X
c6b2dc34 216@item WAV @tab X @tab X
39271be4 217@item WavPack @tab @tab X
913c3e2c 218@item Wing Commander III movie @tab @tab X
d698c5d3 219 @tab Multimedia format used in Origin's Wing Commander III computer game.
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220@item Westwood Studios audio @tab @tab X
221 @tab Multimedia format used in Westwood Studios games.
222@item Westwood Studios VQA @tab @tab X
223 @tab Multimedia format used in Westwood Studios games.
39271be4 224@item YUV4MPEG pipe @tab X @tab X
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225@end multitable
226
227@code{X} means that encoding (resp. decoding) is supported.
228
229@section Image Formats
230
231FFmpeg can read and write images for each frame of a video sequence. The
232following image formats are supported:
233
234@multitable @columnfractions .4 .1 .1 .4
b3de4544 235@item Name @tab Encoding @tab Decoding @tab Comments
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236@item .Y.U.V @tab X @tab X
237 @tab one raw file per component
238@item animated GIF @tab X @tab X
239 @tab Only uncompressed GIFs are generated.
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240@item BMP @tab X @tab X
241 @tab Microsoft BMP image
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242@item JPEG @tab X @tab X
243 @tab Progressive JPEG is not supported.
244@item JPEG 2000 @tab @tab E
245 @tab decoding supported through external library libopenjpeg
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246@item JPEG-LS @tab X @tab X
247@item LJPEG @tab X @tab
248 @tab Lossless JPEG
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249@item PAM @tab X @tab X
250 @tab PAM is a PNM extension with alpha support.
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251@item PBM @tab X @tab X
252 @tab Portable BitMap image
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253@item PCX @tab @tab X
254 @tab PC Paintbrush
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255@item PGM @tab X @tab X
256 @tab Portable GrayMap image
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257@item PGMYUV @tab X @tab X
258 @tab PGM with U and V components in YUV 4:2:0
259@item PNG @tab X @tab X
260 @tab 2/4 bpp not supported yet
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261@item PPM @tab X @tab X
262 @tab Portable PixelMap image
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263@item PTX @tab @tab X
264 @tab V.Flash PTX format
265@item RAS @tab @tab X
266 @tab Sun Rasterfile
267@item SGI @tab X @tab X
268 @tab SGI RGB image format
21d4af5d 269@item Targa @tab X @tab X
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270 @tab Targa (.TGA) image format
271@item TIFF @tab X @tab X
272 @tab YUV, JPEG and some extension is not supported yet.
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273@end multitable
274
275@code{X} means that encoding (resp. decoding) is supported.
276
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277@code{E} means that support is provided through an external library.
278
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279@section Video Codecs
280
281@multitable @columnfractions .4 .1 .1 .4
b3de4544 282@item Name @tab Encoding @tab Decoding @tab Comments
d66d8b83 283@item 4X Video @tab @tab X
d698c5d3 284 @tab Used in certain computer games.
913c3e2c 285@item American Laser Games MM @tab @tab X
d698c5d3 286 @tab Used in games like Mad Dog McCree.
d66d8b83 287@item AMV @tab @tab X
d698c5d3 288 @tab Used in Chinese MP3 players.
d66d8b83 289@item Apple Animation @tab X @tab X
d698c5d3 290 @tab fourcc: 'rle '
d66d8b83 291@item Apple Graphics @tab @tab X
d698c5d3 292 @tab fourcc: 'smc '
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293@item Apple MJPEG-B @tab @tab X
294@item Apple QuickDraw @tab @tab X
d698c5d3 295 @tab fourcc: qdrw
d66d8b83 296@item Apple Video @tab @tab X
d698c5d3 297 @tab fourcc: rpza
d66d8b83 298@item Asus v1 @tab X @tab X
d698c5d3 299 @tab fourcc: ASV1
d66d8b83 300@item Asus v2 @tab X @tab X
d698c5d3 301 @tab fourcc: ASV2
d66d8b83 302@item ATI VCR1 @tab @tab X
d698c5d3 303 @tab fourcc: VCR1
d66d8b83 304@item ATI VCR2 @tab @tab X
d698c5d3 305 @tab fourcc: VCR2
d66d8b83 306@item Autodesk RLE @tab @tab X
d698c5d3 307 @tab fourcc: AASC
d66d8b83 308@item AVID DNxHD @tab X @tab X
d698c5d3 309 @tab aka SMPTE VC3
bac4c85c 310@item AVS video @tab @tab X
d698c5d3 311 @tab Video encoding used by the Creature Shock game.
d66d8b83 312@item Bethsoft VID @tab @tab X
d698c5d3 313 @tab Used in some games from Bethesda Softworks.
bac4c85c 314@item C93 video @tab @tab X
d698c5d3 315 @tab Codec used in Cyberia game.
d66d8b83 316@item CamStudio @tab @tab X
d698c5d3 317 @tab fourcc: CSCD
bac4c85c 318@item Cin video @tab @tab X
d698c5d3 319 @tab Codec used in Delphine Software games.
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320@item Cinepak @tab @tab X
321@item Cirrus Logic AccuPak @tab @tab X
d698c5d3 322 @tab fourcc: CLJR
d66d8b83 323@item Creative YUV @tab @tab X
d698c5d3 324 @tab fourcc: CYUV
82ced5a9 325@item Dirac @tab E @tab E
360f980b 326 @tab supported through external libdirac/libschroedinger libraries
d66d8b83 327@item Duck TrueMotion v1 @tab @tab X
d698c5d3 328 @tab fourcc: DUCK
d66d8b83 329@item Duck TrueMotion v2 @tab @tab X
d698c5d3 330 @tab fourcc: TM20
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331@item DV @tab X @tab X
332@item DXA Video @tab @tab X
d698c5d3 333 @tab Codec originally used in Feeble Files game.
d66d8b83 334@item Electronic Arts CMV @tab @tab X
d698c5d3 335 @tab Used in NHL 95 game.
cfc78718 336@item Electronic Arts TGV @tab @tab X
42b30357 337@item Electronic Arts TGQ @tab @tab X
d8964f3a 338@item Electronic Arts TQI @tab @tab X
d66d8b83 339@item FFmpeg Video 1 @tab X @tab X
d698c5d3 340 @tab experimental lossless codec (fourcc: FFV1)
d66d8b83 341@item Flash Screen Video @tab X @tab X
d698c5d3 342 @tab fourcc: FSV1
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343@item FLIC video @tab @tab X
344@item FLV @tab X @tab X
d698c5d3 345 @tab Sorenson H.263 used in Flash
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346@item Fraps FPS1 @tab @tab X
347@item H.261 @tab X @tab X
348@item H.263(+) @tab X @tab X
d698c5d3 349 @tab also known as RealVideo 1.0
82ced5a9 350@item H.264 @tab E @tab X
360f980b 351 @tab encoding supported through external library libx264
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352@item HuffYUV @tab X @tab X
353@item IBM Ultimotion @tab @tab X
d698c5d3 354 @tab fourcc: ULTI
bac4c85c 355@item id Cinematic video @tab @tab X
d698c5d3 356 @tab Used in Quake II.
d66d8b83 357@item id RoQ @tab X @tab X
d698c5d3 358 @tab Used in Quake III, Jedi Knight 2, other computer games.
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359@item Intel Indeo 3 @tab @tab X
360@item Interplay Video @tab @tab X
d698c5d3 361 @tab Used in Interplay .MVE files.
d66d8b83 362@item JPEG-LS @tab X @tab X
d698c5d3 363 @tab fourcc: MJLS, lossless and near-lossless is supported.
d66d8b83 364@item KMVC @tab @tab X
d698c5d3 365 @tab Codec used in Worms games.
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366@item LOCO @tab @tab X
367@item lossless MJPEG @tab X @tab X
368@item Microsoft RLE @tab @tab X
369@item Microsoft Video-1 @tab @tab X
370@item Mimic @tab @tab X
d698c5d3 371 @tab Used in MSN Messenger Webcam streams.
d66d8b83 372@item Miro VideoXL @tab @tab X
d698c5d3 373 @tab fourcc: VIXL
eacf8613 374@item MJPEG (Motion JPEG) @tab X @tab X
822cc8f7 375@item Motion Pixels Video @tab @tab X
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376@item MPEG-1 @tab X @tab X
377@item MPEG-2 @tab X @tab X
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378@item MPEG-4 @tab X @tab X
379@item MSMPEG4 V1 @tab X @tab X
380@item MSMPEG4 V2 @tab X @tab X
381@item MSMPEG4 V3 @tab X @tab X
d66d8b83 382@item MSZH @tab @tab X
d698c5d3 383 @tab Part of LCL
eacf8613 384@item Nintendo Gamecube THP video @tab @tab X
d66d8b83 385@item On2 VP3 @tab @tab X
d698c5d3 386 @tab still experimental
d66d8b83 387@item On2 VP5 @tab @tab X
d698c5d3 388 @tab fourcc: VP50
d66d8b83 389@item On2 VP6 @tab @tab X
d698c5d3 390 @tab fourcc: VP60,VP61,VP62
d66d8b83 391@item planar RGB @tab @tab X
d698c5d3 392 @tab fourcc: 8BPS
d66d8b83 393@item QPEG @tab @tab X
d698c5d3 394 @tab fourccs: QPEG, Q1.0, Q1.1
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395@item RealVideo 1.0 @tab X @tab X
396@item RealVideo 2.0 @tab X @tab X
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397@item RealVideo 3.0 @tab @tab X
398 @tab still far from ideal
11c0f9ec 399@item RealVideo 4.0 @tab @tab X
d66d8b83 400@item Renderware TXD @tab @tab X
d698c5d3 401 @tab Texture dictionaries used by the Renderware Engine.
d66d8b83 402@item RTjpeg @tab @tab X
d698c5d3 403 @tab Video encoding used in NuppelVideo files.
bac4c85c 404@item Smacker video @tab @tab X
d698c5d3 405 @tab Video encoding used in Smacker.
d66d8b83 406@item Snow @tab X @tab X
d698c5d3 407 @tab experimental wavelet codec (fourcc: SNOW)
eacf8613 408@item Sony PlayStation MDEC (Motion DECoder) @tab @tab X
d66d8b83 409@item Sorenson Video 1 @tab X @tab X
d698c5d3 410 @tab fourcc: SVQ1
d66d8b83 411@item Sorenson Video 3 @tab @tab X
d698c5d3 412 @tab fourcc: SVQ3
d66d8b83 413@item Sunplus MJPEG @tab @tab X
d698c5d3 414 @tab fourcc: SP5X
d66d8b83 415@item TechSmith Camtasia @tab @tab X
d698c5d3 416 @tab fourcc: TSCC
82ced5a9 417@item Theora @tab E @tab X
360f980b 418 @tab encoding supported through external library libtheora
bac4c85c 419@item Tiertex Seq video @tab @tab X
d698c5d3 420 @tab Codec used in DOS CD-ROM FlashBack game.
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421@item VC-1 @tab @tab X
422@item VMD Video @tab @tab X
d698c5d3 423 @tab Used in Sierra VMD files.
eacf8613 424@item VMware Screen Codec / VMware Video @tab @tab X
d698c5d3 425 @tab Codec used in videos captured by VMware.
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426@item Westwood Studios VQA (Vector Quantized Animation) video @tab @tab X
427@item Windows Media Video 8 @tab X @tab X
428@item Wing Commander III / Xan @tab @tab X
429 @tab Used in Wing Commander III .MVE files.
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430@item Winnov WNV1 @tab @tab X
431@item WMV7 @tab X @tab X
d66d8b83 432@item WMV9 @tab @tab X
d698c5d3 433 @tab not completely working
39271be4 434@item YAMAHA SMAF @tab X @tab X
d66d8b83 435@item ZLIB @tab X @tab X
d698c5d3 436 @tab part of LCL, encoder experimental
eacf8613 437@item Zip Motion Blocks Video @tab X @tab X
d698c5d3 438 @tab Encoder works only in PAL8.
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439@end multitable
440
441@code{X} means that encoding (resp. decoding) is supported.
442
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443@code{E} means that support is provided through an external library.
444
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445@section Audio Codecs
446
485ec4f1 447@multitable @columnfractions .4 .1 .1 .4
b3de4544 448@item Name @tab Encoding @tab Decoding @tab Comments
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449@item 4X IMA ADPCM @tab @tab X
450@item 8SVX audio @tab @tab X
82ced5a9 451@item AAC @tab E @tab X
360f980b 452 @tab encoding supported through external library libfaac
270fc177 453@item AC-3 @tab X @tab X
82ced5a9 454@item AMR-NB @tab E @tab E
360f980b 455 @tab supported through external library libamrnb
82ced5a9 456@item AMR-WB @tab E @tab E
360f980b 457 @tab supported through external library libamrwb
16d81b27 458@item AMV IMA ADPCM @tab @tab X
d698c5d3 459 @tab Used in AMV files
833e90dd 460@item Apple lossless audio @tab X @tab X
d698c5d3 461 @tab QuickTime fourcc 'alac'
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462@item Apple MACE 3 @tab @tab X
463@item Apple MACE 6 @tab @tab X
464@item ATRAC 3 @tab @tab X
465@item CD-ROM XA ADPCM @tab @tab X
bac4c85c 466@item Cin audio @tab @tab X
d698c5d3 467 @tab Codec used in Delphine Software International games.
16d81b27 468@item Creative ADPCM @tab @tab X
d698c5d3 469 @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
16d81b27 470@item CRI ADX ADPCM @tab X @tab X
d698c5d3 471 @tab Used in Sega Dreamcast games.
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472@item DSP Group TrueSpeech @tab @tab X
473@item DTS Coherent Audio @tab @tab X
474@item Duck DK3 IMA ADPCM @tab @tab X
d698c5d3 475 @tab Used in some Sega Saturn console games.
16d81b27 476@item Duck DK4 IMA ADPCM @tab @tab X
d698c5d3 477 @tab Used in some Sega Saturn console games.
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478@item DV audio @tab @tab X
479@item Electronic Arts ADPCM @tab @tab X
d698c5d3 480 @tab Used in various EA titles.
44723c84 481@item Enhanced AC-3 @tab @tab X
9a584db4 482@item FLAC lossless audio @tab IX @tab X
16d81b27 483@item G.726 ADPCM @tab X @tab X
82ced5a9 484@item GSM @tab E @tab E
3f33271a 485 @tab supported through external library libgsm
82ced5a9 486@item GSM_MS @tab E @tab E
3f33271a 487 @tab supported through external library libgsm
16d81b27 488@item id RoQ DPCM @tab X @tab X
d698c5d3 489 @tab Used in Quake III, Jedi Knight 2, other computer games.
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490@item Intel Music Coder @tab @tab X
491@item Interplay MVE DPCM @tab @tab X
d698c5d3 492 @tab Used in various Interplay computer games.
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493@item ISS IMA ADPCM @tab @tab X
494 @tab Used in FunCom games.
16d81b27 495@item MAXIS EA ADPCM @tab @tab X
d698c5d3 496 @tab Used in Sim City 3000.
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497@item Microsoft ADPCM @tab X @tab X
498@item MLP/TrueHD @tab @tab X
d698c5d3 499 @tab Used in DVD-Audio and Blu-Ray discs.
16d81b27 500@item Monkey's Audio @tab @tab X
d698c5d3 501 @tab Only versions 3.97-3.99 are supported.
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502@item MPEG audio layer 3 @tab E @tab IX
503 @tab encoding supported through external library LAME
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504@item MPEG audio layer 2 @tab IX @tab IX
505@item MS IMA ADPCM @tab X @tab X
506@item Musepack @tab @tab X
d698c5d3 507 @tab SV7 and SV8 are supported.
755ba886 508@item Nellymoser ASAO @tab X @tab X
73b458e3 509@item QCELP / PureVoice @tab @tab X
16d81b27 510@item Qdesign QDM2 @tab @tab X
d698c5d3 511 @tab There are still some distortions.
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512@item QT IMA ADPCM @tab X @tab X
513@item RA144 @tab @tab X
d698c5d3 514 @tab Real 14400 bit/s codec
16d81b27 515@item RA288 @tab @tab X
d698c5d3 516 @tab Real 28800 bit/s codec
575a5bf2 517@item RADnet @tab IX @tab IX
a692130f 518 @tab Real low bitrate AC-3 codec
16d81b27 519@item Real COOK @tab @tab X
d698c5d3 520 @tab All versions except 5.1 are supported.
bac4c85c 521@item Shorten @tab @tab X
16d81b27 522@item Sierra Online DPCM @tab @tab X
d698c5d3 523 @tab Used in Sierra Online game audio files.
bac4c85c 524@item Smacker audio @tab @tab X
16d81b27 525@item SMJPEG IMA ADPCM @tab @tab X
d698c5d3 526 @tab Used in certain Loki game ports.
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527@item Sonic @tab X @tab X
528 @tab experimental codec
529@item Sonic lossless @tab X @tab X
530 @tab experimental codec
82ced5a9 531@item Speex @tab @tab E
360f980b 532 @tab supported through external library libspeex
16d81b27 533@item THP ADPCM @tab @tab X
d698c5d3 534 @tab Used on the Nintendo GameCube.
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535@item True Audio (TTA) @tab @tab X
536@item Vorbis @tab X @tab X
bac4c85c 537@item WavPack @tab @tab X
16d81b27 538@item Westwood Studios IMA ADPCM @tab @tab X
d698c5d3 539 @tab Used in Westwood Studios games like Command and Conquer.
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540@item Westwood Audio (SND1) @tab @tab X
541@item Windows Media Audio 1 @tab X @tab X
542@item Windows Media Audio 2 @tab X @tab X
16d81b27 543@item Xan DPCM @tab @tab X
d698c5d3 544 @tab Used in Origin's Wing Commander IV AVI files.
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545@end multitable
546
547@code{X} means that encoding (resp. decoding) is supported.
548
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549@code{E} means that support is provided through an external library.
550
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551@code{I} means that an integer-only version is available, too (ensures high
552performance on systems without hardware floating point support).
553
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554@section Subtitle Formats
555
485ec4f1 556@multitable @columnfractions .4 .1 .1 .1 .1 .1
9afc2917 557@item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding
913c3e2c 558@item SSA/ASS @tab X @tab X
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559@item DVB @tab X @tab X @tab X @tab X
560@item DVD @tab X @tab X @tab X @tab X
561@item XSUB @tab @tab @tab @tab X
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562@end multitable
563
564@code{X} means that the feature is supported.
565
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566@section Network Protocols
567
568@multitable @columnfractions .4 .1 .1 .1 .1 .1
569@item Name @tab Support
570@item file @tab X
571@item Gopher @tab X
572@item HTTP @tab X
573@item pipe @tab X
574@item RTP @tab X
575@item TCP @tab X
576@item UDP @tab X
577@end multitable
578
579@code{X} means that the protocol is supported.
580
581
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582@chapter Platform Specific information
583
584@section BSD
585
586BSD make will not build FFmpeg, you need to install and use GNU Make
587(@file{gmake}).
588
589@section Windows
590
46a845d0 591To get help and instructions for building FFmpeg under Windows, check out
d0e1cd3d 592the FFmpeg Windows Help Forum at
ab5ce4ae 593@url{http://ffmpeg.arrozcru.org/}.
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594
595@subsection Native Windows compilation
596
c1989552 597FFmpeg can be built to run natively on Windows using the MinGW tools. Install
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598the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
599You can find detailed installation
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600instructions in the download section and the FAQ.
601
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602FFmpeg does not build out-of-the-box with the packages the automated MinGW
603installer provides. It also requires coreutils to be installed and many other
604packages updated to the latest version. The minimum version for some packages
605are listed below:
606
607@itemize
608@item bash 3.1
609@item msys-make 3.81-2 (note: not mingw32-make)
2014b51c 610@item w32api 3.13
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611@item mingw-runtime 3.15
612@end itemize
613
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614You will also need to pass @code{-fno-common} to the compiler to work around
615a GCC bug (see @url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216}).
616
c1989552 617Within the MSYS shell, configure and make with:
d0e1cd3d 618
c1989552 619@example
0f898714 620./configure --enable-memalign-hack --extra-cflags=-fno-common
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621make
622make install
623@end example
d0e1cd3d 624
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625This will install @file{ffmpeg.exe} along with many other development files
626to @file{/usr/local}. You may specify another install path using the
627@code{--prefix} option in @file{configure}.
d0e1cd3d 628
c1989552 629Notes:
d0e1cd3d 630
c1989552 631@itemize
d0e1cd3d 632
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633@item In order to compile vhooks, you must have a POSIX-compliant libdl in
634your MinGW system. Get dlfcn-win32 from
635@url{http://code.google.com/p/dlfcn-win32}.
d0e1cd3d 636
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637@item In order to compile FFplay, you must have the MinGW development library
638of SDL. Get it from @url{http://www.libsdl.org}.
639Edit the @file{bin/sdl-config} script so that it points to the correct prefix
640where SDL was installed. Verify that @file{sdl-config} can be launched from
641the MSYS command line.
d0e1cd3d 642
d0e1cd3d 643@item By using @code{./configure --enable-shared} when configuring FFmpeg,
c1989552 644you can build libavutil, libavcodec and libavformat as DLLs.
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645
646@end itemize
647
c1989552 648@subsection Microsoft Visual C++ compatibility
d0e1cd3d 649
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650As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
651want to use the libav* libraries in your own applications, you can still
652compile those applications using MSVC++. But the libav* libraries you link
653to @emph{must} be built with MinGW. However, you will not be able to debug
654inside the libav* libraries, since MSVC++ does not recognize the debug
655symbols generated by GCC.
656We strongly recommend you to move over from MSVC++ to MinGW tools.
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658This description of how to use the FFmpeg libraries with MSVC++ is based on
659Microsoft Visual C++ 2005 Express Edition. If you have a different version,
660you might have to modify the procedures slightly.
d0e1cd3d 661
c1989552 662@subsubsection Using static libraries
d0e1cd3d 663
c1989552 664Assuming you have just built and installed FFmpeg in @file{/usr/local}.
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665
666@enumerate
667
668@item Create a new console application ("File / New / Project") and then
669select "Win32 Console Application". On the appropriate page of the
670Application Wizard, uncheck the "Precompiled headers" option.
671
672@item Write the source code for your application, or, for testing, just
673copy the code from an existing sample application into the source file
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674that MSVC++ has already created for you. For example, you can copy
675@file{output_example.c} from the FFmpeg distribution.
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676
677@item Open the "Project / Properties" dialog box. In the "Configuration"
678combo box, select "All Configurations" so that the changes you make will
679affect both debug and release builds. In the tree view on the left hand
680side, select "C/C++ / General", then edit the "Additional Include
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681Directories" setting to contain the path where the FFmpeg includes were
682installed (i.e. @file{c:\msys\1.0\local\include}).
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683Do not add MinGW's include directory here, or the include files will
684conflict with MSVC's.
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685
686@item Still in the "Project / Properties" dialog box, select
687"Linker / General" from the tree view and edit the
688"Additional Library Directories" setting to contain the @file{lib}
689directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
690the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
691and the directory where MinGW's GCC libs are installed
692(i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
693"Linker / Input" from the tree view, and add the files @file{libavformat.a},
694@file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
695@file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
696to the end of "Additional Dependencies".
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697
698@item Now, select "C/C++ / Code Generation" from the tree view. Select
699"Debug" in the "Configuration" combo box. Make sure that "Runtime
700Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
701the "Configuration" combo box and make sure that "Runtime Library" is
702set to "Multi-threaded DLL".
703
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704@item Click "OK" to close the "Project / Properties" dialog box.
705
706@item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
707Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
708and install it in MSVC++'s include directory
709(i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
710
711@item MSVC++ also does not understand the @code{inline} keyword used by
712FFmpeg, so you must add this line before @code{#include}ing libav*:
713@example
714#define inline _inline
715@end example
716
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717@item Build your application, everything should work.
718
719@end enumerate
720
721@subsubsection Using shared libraries
722
723This is how to create DLL and LIB files that are compatible with MSVC++:
724
725@enumerate
726
727@item Add a call to @file{vcvars32.bat} (which sets up the environment
728variables for the Visual C++ tools) as the first line of @file{msys.bat}.
729The standard location for @file{vcvars32.bat} is
730@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
731and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
732If this corresponds to your setup, add the following line as the first line
733of @file{msys.bat}:
734
735@example
736call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
737@end example
738
739Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
740and run @file{c:\msys\1.0\msys.bat} from there.
741
742@item Within the MSYS shell, run @code{lib.exe}. If you get a help message
743from @file{Microsoft (R) Library Manager}, this means your environment
744variables are set up correctly, the @file{Microsoft (R) Library Manager}
745is on the path and will be used by FFmpeg to create
746MSVC++-compatible import libraries.
747
748@item Build FFmpeg with
749
750@example
751./configure --enable-shared --enable-memalign-hack
752make
753make install
754@end example
755
756Your install path (@file{/usr/local/} by default) should now have the
757necessary DLL and LIB files under the @file{bin} directory.
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758
759@end enumerate
760
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761To use those files with MSVC++, do the same as you would do with
762the static libraries, as described above. But in Step 4,
763you should only need to add the directory where the LIB files are installed
764(i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
765installed in the @file{bin} directory. And instead of adding @file{libxx.a}
766files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
767@file{avutil.lib}. There should be no need for @file{libmingwex.a},
768@file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
769statically linked into the DLLs. The @file{bin} directory contains a bunch
770of DLL files, but the ones that are actually used to run your application
771are the ones with a major version number in their filenames
772(i.e. @file{avcodec-51.dll}).
773
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774@subsection Cross compilation for Windows with Linux
775
776You must use the MinGW cross compilation tools available at
777@url{http://www.mingw.org/}.
778
779Then configure FFmpeg with the following options:
780@example
781./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
782@end example
783(you can change the cross-prefix according to the prefix chosen for the
784MinGW tools).
785
786Then you can easily test FFmpeg with Wine
787(@url{http://www.winehq.com/}).
788
789@subsection Compilation under Cygwin
790
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791The main issue with the 1.5.x Cygwin versions is that newlib, its C library,
792does not contain llrint(). You need to upgrade to the unstable 1.7.x versions,
793or leverage the implementation in MinGW (as explained below).
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794
795Just install your Cygwin with all the "Base" packages, plus the
796following "Devel" ones:
797@example
f496ab12 798binutils, gcc-core, make, subversion, mingw-runtime, diffutils
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799@end example
800
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801The experimental gcc4 package is still buggy, hence please
802use the official gcc 3.4.4 or a 4.2.x compiled from source by yourself.
803
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804Install the current binutils-20080624-2 as they work fine (the old
805binutils-20060709-1 proved buggy on shared builds).
d0e1cd3d 806
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807Then create a small library that just contains llrint():
808
809@example
810ar x /usr/lib/mingw/libmingwex.a llrint.o
811ar cq /usr/local/lib/libllrint.a llrint.o
812@end example
813
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814Then run
815
816@example
29c3d42b 817./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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818@end example
819
820to make a static build or
821
822@example
29c3d42b 823./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
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824@end example
825
826to build shared libraries.
827
828If you want to build FFmpeg with additional libraries, download Cygwin
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829"Devel" packages for Ogg and Vorbis from any Cygwin packages repository:
830@example
831libogg-devel, libvorbis-devel
832@end example
833
834These library packages are only available from Cygwin Ports
be8497b0 835(@url{http://sourceware.org/cygwinports/}) :
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836
837@example
838yasm, libSDL-devel, libdirac-devel, libfaac-devel, libfaad-devel, libgsm-devel,
839libmp3lame-devel, libschroedinger1.0-devel, speex-devel, libtheora-devel,
840libxvidcore-devel
841@end example
842
843The recommendation for libnut and x264 is to build them from source by
844yourself, as they evolve too quickly for Cygwin Ports to be up to date.
d0e1cd3d 845
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846Cygwin 1.7.x has IPv6 support. You can add IPv6 to Cygwin 1.5.x by means
847of the @code{libgetaddrinfo-devel} package, available at Cygwin Ports.
848
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849@subsection Crosscompilation for Windows under Cygwin
850
851With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
852
853Just install your Cygwin as explained before, plus these additional
854"Devel" packages:
855@example
856gcc-mingw-core, mingw-runtime, mingw-zlib
857@end example
858
859and add some special flags to your configure invocation.
860
861For a static build run
862@example
863./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
864@end example
865
866and for a build with shared libraries
867@example
868./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
869@end example
870
871@section BeOS
872
5f757b85 873BeOS support is broken in mysterious ways.
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875@section OS/2
876
877For information about compiling FFmpeg on OS/2 see
878@url{http://www.edm2.com/index.php/FFmpeg}.
879
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880@chapter Developers Guide
881
882@section API
883@itemize @bullet
884@item libavcodec is the library containing the codecs (both encoding and
885decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
886
887@item libavformat is the library containing the file format handling (mux and
888demux code for several formats). Look at @file{ffplay.c} to use it in a
889player. See @file{output_example.c} to use it to generate audio or video
890streams.
891
892@end itemize
893
894@section Integrating libavcodec or libavformat in your program
895
896You can integrate all the source code of the libraries to link them
897statically to avoid any version problem. All you need is to provide a
898'config.mak' and a 'config.h' in the parent directory. See the defines
899generated by ./configure to understand what is needed.
900
901You can use libavcodec or libavformat in your commercial program, but
902@emph{any patch you make must be published}. The best way to proceed is
903to send your patches to the FFmpeg mailing list.
904
905@node Coding Rules
906@section Coding Rules
907
908FFmpeg is programmed in the ISO C90 language with a few additional
909features from ISO C99, namely:
910@itemize @bullet
911@item
912the @samp{inline} keyword;
913@item
914@samp{//} comments;
915@item
916designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
917@item
918compound literals (@samp{x = (struct s) @{ 17, 23 @};})
919@end itemize
920
921These features are supported by all compilers we care about, so we will not
922accept patches to remove their use unless they absolutely do not impair
923clarity and performance.
924
925All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
926compiles with several other compilers, such as the Compaq ccc compiler
927or Sun Studio 9, and we would like to keep it that way unless it would
928be exceedingly involved. To ensure compatibility, please do not use any
929additional C99 features or GCC extensions. Especially watch out for:
930@itemize @bullet
931@item
932mixing statements and declarations;
933@item
934@samp{long long} (use @samp{int64_t} instead);
935@item
936@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
937@item
938GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
939@end itemize
940
941Indent size is 4.
942The presentation is the one specified by 'indent -i4 -kr -nut'.
943The TAB character is forbidden outside of Makefiles as is any
944form of trailing whitespace. Commits containing either will be
945rejected by the Subversion repository.
946
947The main priority in FFmpeg is simplicity and small code size in order to
948minimize the bug count.
949
950Comments: Use the JavaDoc/Doxygen
951format (see examples below) so that code documentation
952can be generated automatically. All nontrivial functions should have a comment
953above them explaining what the function does, even if it is just one sentence.
954All structures and their member variables should be documented, too.
955@example
956/**
957 * @@file mpeg.c
958 * MPEG codec.
959 * @@author ...
960 */
961
962/**
963 * Summary sentence.
964 * more text ...
965 * ...
966 */
967typedef struct Foobar@{
968 int var1; /**< var1 description */
969 int var2; ///< var2 description
970 /** var3 description */
971 int var3;
972@} Foobar;
973
974/**
975 * Summary sentence.
976 * more text ...
977 * ...
978 * @@param my_parameter description of my_parameter
979 * @@return return value description
980 */
981int myfunc(int my_parameter)
982...
983@end example
984
985fprintf and printf are forbidden in libavformat and libavcodec,
986please use av_log() instead.
987
988Casts should be used only when necessary. Unneeded parentheses
989should also be avoided if they don't make the code easier to understand.
990
991@section Development Policy
992
993@enumerate
994@item
995 Contributions should be licensed under the LGPL 2.1, including an
996 "or any later version" clause, or the MIT license. GPL 2 including
997 an "or any later version" clause is also acceptable, but LGPL is
998 preferred.
999@item
1000 You must not commit code which breaks FFmpeg! (Meaning unfinished but
1001 enabled code which breaks compilation or compiles but does not work or
1002 breaks the regression tests)
1003 You can commit unfinished stuff (for testing etc), but it must be disabled
1004 (#ifdef etc) by default so it does not interfere with other developers'
1005 work.
1006@item
1007 You do not have to over-test things. If it works for you, and you think it
1008 should work for others, then commit. If your code has problems
1009 (portability, triggers compiler bugs, unusual environment etc) they will be
1010 reported and eventually fixed.
1011@item
1012 Do not commit unrelated changes together, split them into self-contained
1013 pieces. Also do not forget that if part B depends on part A, but A does not
1014 depend on B, then A can and should be committed first and separate from B.
1015 Keeping changes well split into self-contained parts makes reviewing and
1016 understanding them on the commit log mailing list easier. This also helps
1017 in case of debugging later on.
1018 Also if you have doubts about splitting or not splitting, do not hesitate to
1019 ask/discuss it on the developer mailing list.
1020@item
1021 Do not change behavior of the program (renaming options etc) without
1022 first discussing it on the ffmpeg-devel mailing list. Do not remove
1023 functionality from the code. Just improve!
1024
1025 Note: Redundant code can be removed.
1026@item
1027 Do not commit changes to the build system (Makefiles, configure script)
1028 which change behavior, defaults etc, without asking first. The same
1029 applies to compiler warning fixes, trivial looking fixes and to code
1030 maintained by other developers. We usually have a reason for doing things
1031 the way we do. Send your changes as patches to the ffmpeg-devel mailing
1032 list, and if the code maintainers say OK, you may commit. This does not
1033 apply to files you wrote and/or maintain.
1034@item
1035 We refuse source indentation and other cosmetic changes if they are mixed
1036 with functional changes, such commits will be rejected and removed. Every
1037 developer has his own indentation style, you should not change it. Of course
1038 if you (re)write something, you can use your own style, even though we would
1039 prefer if the indentation throughout FFmpeg was consistent (Many projects
1040 force a given indentation style - we do not.). If you really need to make
1041 indentation changes (try to avoid this), separate them strictly from real
1042 changes.
1043
1044 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1045 then either do NOT change the indentation of the inner part within (do not
1046 move it to the right)! or do so in a separate commit
1047@item
1048 Always fill out the commit log message. Describe in a few lines what you
1049 changed and why. You can refer to mailing list postings if you fix a
1050 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1051@item
1052 If you apply a patch by someone else, include the name and email address in
1053 the log message. Since the ffmpeg-cvslog mailing list is publicly
1054 archived you should add some SPAM protection to the email address. Send an
1055 answer to ffmpeg-devel (or wherever you got the patch from) saying that
1056 you applied the patch.
1057@item
1058 When applying patches that have been discussed (at length) on the mailing
1059 list, reference the thread in the log message.
1060@item
1061 Do NOT commit to code actively maintained by others without permission.
1062 Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
1063 timeframe (12h for build failures and security fixes, 3 days small changes,
1064 1 week for big patches) then commit your patch if you think it is OK.
1065 Also note, the maintainer can simply ask for more time to review!
1066@item
1067 Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1068 are sent there and reviewed by all the other developers. Bugs and possible
1069 improvements or general questions regarding commits are discussed there. We
1070 expect you to react if problems with your code are uncovered.
1071@item
1072 Update the documentation if you change behavior or add features. If you are
1073 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1074 maintainer(s) will review and commit your stuff.
1075@item
1076 Try to keep important discussions and requests (also) on the public
1077 developer mailing list, so that all developers can benefit from them.
1078@item
1079 Never write to unallocated memory, never write over the end of arrays,
1080 always check values read from some untrusted source before using them
1081 as array index or other risky things.
1082@item
1083 Remember to check if you need to bump versions for the specific libav
1084 parts (libavutil, libavcodec, libavformat) you are changing. You need
b98052d5 1085 to change the version integer.
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1086 Incrementing the first component means no backward compatibility to
1087 previous versions (e.g. removal of a function from the public API).
1088 Incrementing the second component means backward compatible change
b98052d5
PR
1089 (e.g. addition of a function to the public API or extension of an
1090 existing data structure).
d0e1cd3d
DB
1091 Incrementing the third component means a noteworthy binary compatible
1092 change (e.g. encoder bug fix that matters for the decoder).
1093@item
53407b64 1094 Compiler warnings indicate potential bugs or code with bad style. If a type of
9908c1a8
DB
1095 warning always points to correct and clean code, that warning should
1096 be disabled, not the code changed.
1097 Thus the remaining warnings can either be bugs or correct code.
beaa4a91 1098 If it is a bug, the bug has to be fixed. If it is not, the code should
9908c1a8
DB
1099 be changed to not generate a warning unless that causes a slowdown
1100 or obfuscates the code.
d0e1cd3d
DB
1101@item
1102 If you add a new file, give it a proper license header. Do not copy and
1103 paste it from a random place, use an existing file as template.
1104@end enumerate
1105
1106We think our rules are not too hard. If you have comments, contact us.
1107
1108Note, these rules are mostly borrowed from the MPlayer project.
1109
1110@section Submitting patches
1111
1112First, (@pxref{Coding Rules}) above if you did not yet.
1113
1114When you submit your patch, try to send a unified diff (diff '-up'
1115option). We cannot read other diffs :-)
1116
1117Also please do not submit a patch which contains several unrelated changes.
1118Split it into separate, self-contained pieces. This does not mean splitting
1119file by file. Instead, make the patch as small as possible while still
1120keeping it as a logical unit that contains an individual change, even
1121if it spans multiple files. This makes reviewing your patches much easier
1122for us and greatly increases your chances of getting your patch applied.
1123
1124Run the regression tests before submitting a patch so that you can
1125verify that there are no big problems.
1126
1127Patches should be posted as base64 encoded attachments (or any other
1128encoding which ensures that the patch will not be trashed during
1129transmission) to the ffmpeg-devel mailing list, see
1130@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1131
1132It also helps quite a bit if you tell us what the patch does (for example
1133'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1134and has no lrint()')
1135
1136Also please if you send several patches, send each patch as a separate mail,
1137do not attach several unrelated patches to the same mail.
1138
28ce1839
RP
1139@section New codecs or formats checklist
1140
1141@enumerate
1142@item
1143 Did you use av_cold for codec initialization and close functions?
1144@item
1145 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
1146 AVInputFormat/AVOutputFormat struct?
1147@item
1148 Did you bump the minor version number in @file{avcodec.h} or
1149 @file{avformat.h}?
1150@item
1151 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
1152@item
1153 Did you add the CodecID to @file{avcodec.h}?
1154@item
1155 If it has a fourcc, did you add it to @file{libavformat/riff.c},
1156 even if it is only a decoder?
1157@item
1158 Did you add a rule to compile the appropriate files in the Makefile?
1159 Remember to do this even if you're just adding a format to a file that is
1160 already being compiled by some other rule, like a raw demuxer.
1161@item
1162 Did you add an entry to the table of supported formats or codecs in the
1163 documentation?
1164@item
1165 Did you add an entry in the Changelog?
1166@item
1167 If it depends on a parser or a library, did you add that dependency in
1168 configure?
1169@item
1170 Did you "svn add" the appropriate files before commiting?
1171@end enumerate
1172
d0e1cd3d
DB
1173@section patch submission checklist
1174
1175@enumerate
1176@item
1177 Do the regression tests pass with the patch applied?
1178@item
2cdba8bf
DB
1179 Does @code{make checkheaders} pass with the patch applied?
1180@item
d0e1cd3d
DB
1181 Is the patch a unified diff?
1182@item
1183 Is the patch against latest FFmpeg SVN?
1184@item
1185 Are you subscribed to ffmpeg-dev?
1186 (the list is subscribers only due to spam)
1187@item
1188 Have you checked that the changes are minimal, so that the same cannot be
1189 achieved with a smaller patch and/or simpler final code?
1190@item
1191 If the change is to speed critical code, did you benchmark it?
1192@item
1193 If you did any benchmarks, did you provide them in the mail?
1194@item
1195 Have you checked that the patch does not introduce buffer overflows or
1196 other security issues?
1197@item
63d247ea
DB
1198 Did you test your decoder or demuxer against damaged data? If no, see
1199 tools/trasher and the noise bitstream filter. Your decoder or demuxer
1200 should not crash or end in a (near) infinite loop when fed damaged data.
b885e0db 1201@item
d0e1cd3d
DB
1202 Is the patch created from the root of the source tree, so it can be
1203 applied with @code{patch -p0}?
1204@item
1205 Does the patch not mix functional and cosmetic changes?
1206@item
1207 Did you add tabs or trailing whitespace to the code? Both are forbidden.
1208@item
1209 Is the patch attached to the email you send?
1210@item
1211 Is the mime type of the patch correct? It should be text/x-diff or
1212 text/x-patch or at least text/plain and not application/octet-stream.
1213@item
1214 If the patch fixes a bug, did you provide a verbose analysis of the bug?
1215@item
1216 If the patch fixes a bug, did you provide enough information, including
1217 a sample, so the bug can be reproduced and the fix can be verified?
1218 Note please do not attach samples >100k to mails but rather provide a
0fa5f24c 1219 URL, you can upload to ftp://upload.ffmpeg.org
d0e1cd3d
DB
1220@item
1221 Did you provide a verbose summary about what the patch does change?
1222@item
1223 Did you provide a verbose explanation why it changes things like it does?
1224@item
1225 Did you provide a verbose summary of the user visible advantages and
1226 disadvantages if the patch is applied?
1227@item
1228 Did you provide an example so we can verify the new feature added by the
1229 patch easily?
1230@item
1231 If you added a new file, did you insert a license header? It should be
1232 taken from FFmpeg, not randomly copied and pasted from somewhere else.
1233@item
1234 You should maintain alphabetical order in alphabetically ordered lists as
1235 long as doing so does not break API/ABI compatibility.
1236@item
1237 Lines with similar content should be aligned vertically when doing so
1238 improves readability.
1239@item
1240 Did you provide a suggestion for a clear commit log message?
1241@end enumerate
1242
1243@section Patch review process
1244
1245All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1246clear note that the patch is not for SVN.
1247Reviews and comments will be posted as replies to the patch on the
1248mailing list. The patch submitter then has to take care of every comment,
1249that can be by resubmitting a changed patch or by discussion. Resubmitted
1250patches will themselves be reviewed like any other patch. If at some point
1251a patch passes review with no comments then it is approved, that can for
1252simple and small patches happen immediately while large patches will generally
1253have to be changed and reviewed many times before they are approved.
1254After a patch is approved it will be committed to the repository.
1255
1256We will review all submitted patches, but sometimes we are quite busy so
1257especially for large patches this can take several weeks.
1258
1259When resubmitting patches, please do not make any significant changes
1260not related to the comments received during review. Such patches will
1261be rejected. Instead, submit significant changes or new features as
1262separate patches.
1263
1264@section Regression tests
1265
1266Before submitting a patch (or committing to the repository), you should at least
1267test that you did not break anything.
1268
1269The regression tests build a synthetic video stream and a synthetic
1270audio stream. These are then encoded and decoded with all codecs or
1271formats. The CRC (or MD5) of each generated file is recorded in a
1272result file. A 'diff' is launched to compare the reference results and
1273the result file.
1274
1275The regression tests then go on to test the FFserver code with a
1276limited set of streams. It is important that this step runs correctly
1277as well.
1278
1279Run 'make test' to test all the codecs and formats.
1280
1281Run 'make fulltest' to test all the codecs, formats and FFserver.
1282
1283[Of course, some patches may change the results of the regression tests. In
1284this case, the reference results of the regression tests shall be modified
1285accordingly].
1286
1287@bye