1 Copyright (C) 2001 Fabrice Bellard 2 3 FFmpeg is free software; you can redistribute it and/or 4 modify it under the terms of the GNU Lesser General Public 5 License as published by the Free Software Foundation; either 6 version 2.1 of the License, or (at your option) any later version. 7 8 FFmpeg is distributed in the hope that it will be useful, 9 but WITHOUT ANY WARRANTY; without even the implied warranty of 10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 Lesser General Public License for more details. 12 13 You should have received a copy of the GNU Lesser General Public 14 License along with FFmpeg; if not, write to the Free Software 15 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 16 17 ================================================================================== 18 19 GNU LESSER GENERAL PUBLIC LICENSE 20 Version 2.1, February 1999 21 22 Copyright (C) 1991, 1999 Free Software Foundation, Inc. 23 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 24 Everyone is permitted to copy and distribute verbatim copies 25 of this license document, but changing it is not allowed. 26 27 [This is the first released version of the Lesser GPL. It also counts 28 as the successor of the GNU Library Public License, version 2, hence 29 the version number 2.1.] 30 31 Preamble 32 33 The licenses for most software are designed to take away your 34 freedom to share and change it. By contrast, the GNU General Public 35 Licenses are intended to guarantee your freedom to share and change 36 free software--to make sure the software is free for all its users. 37 38 This license, the Lesser General Public License, applies to some 39 specially designated software packages--typically libraries--of the 40 Free Software Foundation and other authors who decide to use it. You 41 can use it too, but we suggest you first think carefully about whether 42 this license or the ordinary General Public License is the better 43 strategy to use in any particular case, based on the explanations below. 44 45 When we speak of free software, we are referring to freedom of use, 46 not price. Our General Public Licenses are designed to make sure that 47 you have the freedom to distribute copies of free software (and charge 48 for this service if you wish); that you receive source code or can get 49 it if you want it; that you can change the software and use pieces of 50 it in new free programs; and that you are informed that you can do 51 these things. 52 53 To protect your rights, we need to make restrictions that forbid 54 distributors to deny you these rights or to ask you to surrender these 55 rights. These restrictions translate to certain responsibilities for 56 you if you distribute copies of the library or if you modify it. 57 58 For example, if you distribute copies of the library, whether gratis 59 or for a fee, you must give the recipients all the rights that we gave 60 you. You must make sure that they, too, receive or can get the source 61 code. If you link other code with the library, you must provide 62 complete object files to the recipients, so that they can relink them 63 with the library after making changes to the library and recompiling 64 it. And you must show them these terms so they know their rights. 65 66 We protect your rights with a two-step method: (1) we copyright the 67 library, and (2) we offer you this license, which gives you legal 68 permission to copy, distribute and/or modify the library. 69 70 To protect each distributor, we want to make it very clear that 71 there is no warranty for the free library. Also, if the library is 72 modified by someone else and passed on, the recipients should know 73 that what they have is not the original version, so that the original 74 author's reputation will not be affected by problems that might be 75 introduced by others. 76 78 Finally, software patents pose a constant threat to the existence of 79 any free program. We wish to make sure that a company cannot 80 effectively restrict the users of a free program by obtaining a 81 restrictive license from a patent holder. Therefore, we insist that 82 any patent license obtained for a version of the library must be 83 consistent with the full freedom of use specified in this license. 84 85 Most GNU software, including some libraries, is covered by the 86 ordinary GNU General Public License. This license, the GNU Lesser 87 General Public License, applies to certain designated libraries, and 88 is quite different from the ordinary General Public License. We use 89 this license for certain libraries in order to permit linking those 90 libraries into non-free programs. 91 92 When a program is linked with a library, whether statically or using 93 a shared library, the combination of the two is legally speaking a 94 combined work, a derivative of the original library. The ordinary 95 General Public License therefore permits such linking only if the 96 entire combination fits its criteria of freedom. The Lesser General 97 Public License permits more lax criteria for linking other code with 98 the library. 99 100 We call this license the "Lesser" General Public License because it 101 does Less to protect the user's freedom than the ordinary General 102 Public License. It also provides other free software developers Less 103 of an advantage over competing non-free programs. These disadvantages 104 are the reason we use the ordinary General Public License for many 105 libraries. However, the Lesser license provides advantages in certain 106 special circumstances. 107 108 For example, on rare occasions, there may be a special need to 109 encourage the widest possible use of a certain library, so that it becomes 110 a de-facto standard. To achieve this, non-free programs must be 111 allowed to use the library. A more frequent case is that a free 112 library does the same job as widely used non-free libraries. In this 113 case, there is little to gain by limiting the free library to free 114 software only, so we use the Lesser General Public License. 115 116 In other cases, permission to use a particular library in non-free 117 programs enables a greater number of people to use a large body of 118 free software. For example, permission to use the GNU C Library in 119 non-free programs enables many more people to use the whole GNU 120 operating system, as well as its variant, the GNU/Linux operating 121 system. 122 123 Although the Lesser General Public License is Less protective of the 124 users' freedom, it does ensure that the user of a program that is 125 linked with the Library has the freedom and the wherewithal to run 126 that program using a modified version of the Library. 127 128 The precise terms and conditions for copying, distribution and 129 modification follow. Pay close attention to the difference between a 130 "work based on the library" and a "work that uses the library". The 131 former contains code derived from the library, whereas the latter must 132 be combined with the library in order to run. 133 135 GNU LESSER GENERAL PUBLIC LICENSE 136 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 137 138 0. This License Agreement applies to any software library or other 139 program which contains a notice placed by the copyright holder or 140 other authorized party saying it may be distributed under the terms of 141 this Lesser General Public License (also called "this License"). 142 Each licensee is addressed as "you". 143 144 A "library" means a collection of software functions and/or data 145 prepared so as to be conveniently linked with application programs 146 (which use some of those functions and data) to form executables. 147 148 The "Library", below, refers to any such software library or work 149 which has been distributed under these terms. A "work based on the 150 Library" means either the Library or any derivative work under 151 copyright law: that is to say, a work containing the Library or a 152 portion of it, either verbatim or with modifications and/or translated 153 straightforwardly into another language. (Hereinafter, translation is 154 included without limitation in the term "modification".) 155 156 "Source code" for a work means the preferred form of the work for 157 making modifications to it. For a library, complete source code means 158 all the source code for all modules it contains, plus any associated 159 interface definition files, plus the scripts used to control compilation 160 and installation of the library. 161 162 Activities other than copying, distribution and modification are not 163 covered by this License; they are outside its scope. The act of 164 running a program using the Library is not restricted, and output from 165 such a program is covered only if its contents constitute a work based 166 on the Library (independent of the use of the Library in a tool for 167 writing it). Whether that is true depends on what the Library does 168 and what the program that uses the Library does. 169 170 1. You may copy and distribute verbatim copies of the Library's 171 complete source code as you receive it, in any medium, provided that 172 you conspicuously and appropriately publish on each copy an 173 appropriate copyright notice and disclaimer of warranty; keep intact 174 all the notices that refer to this License and to the absence of any 175 warranty; and distribute a copy of this License along with the 176 Library. 177 178 You may charge a fee for the physical act of transferring a copy, 179 and you may at your option offer warranty protection in exchange for a 180 fee. 181 183 2. You may modify your copy or copies of the Library or any portion 184 of it, thus forming a work based on the Library, and copy and 185 distribute such modifications or work under the terms of Section 1 186 above, provided that you also meet all of these conditions: 187 188 a) The modified work must itself be a software library. 189 190 b) You must cause the files modified to carry prominent notices 191 stating that you changed the files and the date of any change. 192 193 c) You must cause the whole of the work to be licensed at no 194 charge to all third parties under the terms of this License. 195 196 d) If a facility in the modified Library refers to a function or a 197 table of data to be supplied by an application program that uses 198 the facility, other than as an argument passed when the facility 199 is invoked, then you must make a good faith effort to ensure that, 200 in the event an application does not supply such function or 201 table, the facility still operates, and performs whatever part of 202 its purpose remains meaningful. 203 204 (For example, a function in a library to compute square roots has 205 a purpose that is entirely well-defined independent of the 206 application. Therefore, Subsection 2d requires that any 207 application-supplied function or table used by this function must 208 be optional: if the application does not supply it, the square 209 root function must still compute square roots.) 210 211 These requirements apply to the modified work as a whole. If 212 identifiable sections of that work are not derived from the Library, 213 and can be reasonably considered independent and separate works in 214 themselves, then this License, and its terms, do not apply to those 215 sections when you distribute them as separate works. But when you 216 distribute the same sections as part of a whole which is a work based 217 on the Library, the distribution of the whole must be on the terms of 218 this License, whose permissions for other licensees extend to the 219 entire whole, and thus to each and every part regardless of who wrote 220 it. 221 222 Thus, it is not the intent of this section to claim rights or contest 223 your rights to work written entirely by you; rather, the intent is to 224 exercise the right to control the distribution of derivative or 225 collective works based on the Library. 226 227 In addition, mere aggregation of another work not based on the Library 228 with the Library (or with a work based on the Library) on a volume of 229 a storage or distribution medium does not bring the other work under 230 the scope of this License. 231 232 3. You may opt to apply the terms of the ordinary GNU General Public 233 License instead of this License to a given copy of the Library. To do 234 this, you must alter all the notices that refer to this License, so 235 that they refer to the ordinary GNU General Public License, version 2, 236 instead of to this License. (If a newer version than version 2 of the 237 ordinary GNU General Public License has appeared, then you can specify 238 that version instead if you wish.) Do not make any other change in 239 these notices. 240 242 Once this change is made in a given copy, it is irreversible for 243 that copy, so the ordinary GNU General Public License applies to all 244 subsequent copies and derivative works made from that copy. 245 246 This option is useful when you wish to copy part of the code of 247 the Library into a program that is not a library. 248 249 4. You may copy and distribute the Library (or a portion or 250 derivative of it, under Section 2) in object code or executable form 251 under the terms of Sections 1 and 2 above provided that you accompany 252 it with the complete corresponding machine-readable source code, which 253 must be distributed under the terms of Sections 1 and 2 above on a 254 medium customarily used for software interchange. 255 256 If distribution of object code is made by offering access to copy 257 from a designated place, then offering equivalent access to copy the 258 source code from the same place satisfies the requirement to 259 distribute the source code, even though third parties are not 260 compelled to copy the source along with the object code. 261 262 5. A program that contains no derivative of any portion of the 263 Library, but is designed to work with the Library by being compiled or 264 linked with it, is called a "work that uses the Library". Such a 265 work, in isolation, is not a derivative work of the Library, and 266 therefore falls outside the scope of this License. 267 268 However, linking a "work that uses the Library" with the Library 269 creates an executable that is a derivative of the Library (because it 270 contains portions of the Library), rather than a "work that uses the 271 library". The executable is therefore covered by this License. 272 Section 6 states terms for distribution of such executables. 273 274 When a "work that uses the Library" uses material from a header file 275 that is part of the Library, the object code for the work may be a 276 derivative work of the Library even though the source code is not. 277 Whether this is true is especially significant if the work can be 278 linked without the Library, or if the work is itself a library. The 279 threshold for this to be true is not precisely defined by law. 280 281 If such an object file uses only numerical parameters, data 282 structure layouts and accessors, and small macros and small inline 283 functions (ten lines or less in length), then the use of the object 284 file is unrestricted, regardless of whether it is legally a derivative 285 work. (Executables containing this object code plus portions of the 286 Library will still fall under Section 6.) 287 288 Otherwise, if the work is a derivative of the Library, you may 289 distribute the object code for the work under the terms of Section 6. 290 Any executables containing that work also fall under Section 6, 291 whether or not they are linked directly with the Library itself. 292 294 6. As an exception to the Sections above, you may also combine or 295 link a "work that uses the Library" with the Library to produce a 296 work containing portions of the Library, and distribute that work 297 under terms of your choice, provided that the terms permit 298 modification of the work for the customer's own use and reverse 299 engineering for debugging such modifications. 300 301 You must give prominent notice with each copy of the work that the 302 Library is used in it and that the Library and its use are covered by 303 this License. You must supply a copy of this License. If the work 304 during execution displays copyright notices, you must include the 305 copyright notice for the Library among them, as well as a reference 306 directing the user to the copy of this License. Also, you must do one 307 of these things: 308 309 a) Accompany the work with the complete corresponding 310 machine-readable source code for the Library including whatever 311 changes were used in the work (which must be distributed under 312 Sections 1 and 2 above); and, if the work is an executable linked 313 with the Library, with the complete machine-readable "work that 314 uses the Library", as object code and/or source code, so that the 315 user can modify the Library and then relink to produce a modified 316 executable containing the modified Library. (It is understood 317 that the user who changes the contents of definitions files in the 318 Library will not necessarily be able to recompile the application 319 to use the modified definitions.) 320 321 b) Use a suitable shared library mechanism for linking with the 322 Library. A suitable mechanism is one that (1) uses at run time a 323 copy of the library already present on the user's computer system, 324 rather than copying library functions into the executable, and (2) 325 will operate properly with a modified version of the library, if 326 the user installs one, as long as the modified version is 327 interface-compatible with the version that the work was made with. 328 329 c) Accompany the work with a written offer, valid for at 330 least three years, to give the same user the materials 331 specified in Subsection 6a, above, for a charge no more 332 than the cost of performing this distribution. 333 334 d) If distribution of the work is made by offering access to copy 335 from a designated place, offer equivalent access to copy the above 336 specified materials from the same place. 337 338 e) Verify that the user has already received a copy of these 339 materials or that you have already sent this user a copy. 340 341 For an executable, the required form of the "work that uses the 342 Library" must include any data and utility programs needed for 343 reproducing the executable from it. However, as a special exception, 344 the materials to be distributed need not include anything that is 345 normally distributed (in either source or binary form) with the major 346 components (compiler, kernel, and so on) of the operating system on 347 which the executable runs, unless that component itself accompanies 348 the executable. 349 350 It may happen that this requirement contradicts the license 351 restrictions of other proprietary libraries that do not normally 352 accompany the operating system. Such a contradiction means you cannot 353 use both them and the Library together in an executable that you 354 distribute. 355 357 7. You may place library facilities that are a work based on the 358 Library side-by-side in a single library together with other library 359 facilities not covered by this License, and distribute such a combined 360 library, provided that the separate distribution of the work based on 361 the Library and of the other library facilities is otherwise 362 permitted, and provided that you do these two things: 363 364 a) Accompany the combined library with a copy of the same work 365 based on the Library, uncombined with any other library 366 facilities. This must be distributed under the terms of the 367 Sections above. 368 369 b) Give prominent notice with the combined library of the fact 370 that part of it is a work based on the Library, and explaining 371 where to find the accompanying uncombined form of the same work. 372 373 8. You may not copy, modify, sublicense, link with, or distribute 374 the Library except as expressly provided under this License. Any 375 attempt otherwise to copy, modify, sublicense, link with, or 376 distribute the Library is void, and will automatically terminate your 377 rights under this License. However, parties who have received copies, 378 or rights, from you under this License will not have their licenses 379 terminated so long as such parties remain in full compliance. 380 381 9. You are not required to accept this License, since you have not 382 signed it. However, nothing else grants you permission to modify or 383 distribute the Library or its derivative works. These actions are 384 prohibited by law if you do not accept this License. Therefore, by 385 modifying or distributing the Library (or any work based on the 386 Library), you indicate your acceptance of this License to do so, and 387 all its terms and conditions for copying, distributing or modifying 388 the Library or works based on it. 389 390 10. Each time you redistribute the Library (or any work based on the 391 Library), the recipient automatically receives a license from the 392 original licensor to copy, distribute, link with or modify the Library 393 subject to these terms and conditions. You may not impose any further 394 restrictions on the recipients' exercise of the rights granted herein. 395 You are not responsible for enforcing compliance by third parties with 396 this License. 397 399 11. If, as a consequence of a court judgment or allegation of patent 400 infringement or for any other reason (not limited to patent issues), 401 conditions are imposed on you (whether by court order, agreement or 402 otherwise) that contradict the conditions of this License, they do not 403 excuse you from the conditions of this License. If you cannot 404 distribute so as to satisfy simultaneously your obligations under this 405 License and any other pertinent obligations, then as a consequence you 406 may not distribute the Library at all. For example, if a patent 407 license would not permit royalty-free redistribution of the Library by 408 all those who receive copies directly or indirectly through you, then 409 the only way you could satisfy both it and this License would be to 410 refrain entirely from distribution of the Library. 411 412 If any portion of this section is held invalid or unenforceable under any 413 particular circumstance, the balance of the section is intended to apply, 414 and the section as a whole is intended to apply in other circumstances. 415 416 It is not the purpose of this section to induce you to infringe any 417 patents or other property right claims or to contest validity of any 418 such claims; this section has the sole purpose of protecting the 419 integrity of the free software distribution system which is 420 implemented by public license practices. Many people have made 421 generous contributions to the wide range of software distributed 422 through that system in reliance on consistent application of that 423 system; it is up to the author/donor to decide if he or she is willing 424 to distribute software through any other system and a licensee cannot 425 impose that choice. 426 427 This section is intended to make thoroughly clear what is believed to 428 be a consequence of the rest of this License. 429 430 12. If the distribution and/or use of the Library is restricted in 431 certain countries either by patents or by copyrighted interfaces, the 432 original copyright holder who places the Library under this License may add 433 an explicit geographical distribution limitation excluding those countries, 434 so that distribution is permitted only in or among countries not thus 435 excluded. In such case, this License incorporates the limitation as if 436 written in the body of this License. 437 438 13. The Free Software Foundation may publish revised and/or new 439 versions of the Lesser General Public License from time to time. 440 Such new versions will be similar in spirit to the present version, 441 but may differ in detail to address new problems or concerns. 442 443 Each version is given a distinguishing version number. If the Library 444 specifies a version number of this License which applies to it and 445 "any later version", you have the option of following the terms and 446 conditions either of that version or of any later version published by 447 the Free Software Foundation. If the Library does not specify a 448 license version number, you may choose any version ever published by 449 the Free Software Foundation. 450 452 14. If you wish to incorporate parts of the Library into other free 453 programs whose distribution conditions are incompatible with these, 454 write to the author to ask for permission. For software which is 455 copyrighted by the Free Software Foundation, write to the Free 456 Software Foundation; we sometimes make exceptions for this. Our 457 decision will be guided by the two goals of preserving the free status 458 of all derivatives of our free software and of promoting the sharing 459 and reuse of software generally. 460 461 NO WARRANTY 462 463 15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO 464 WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW. 465 EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR 466 OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY 467 KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE 468 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 469 PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE 470 LIBRARY IS WITH YOU. SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME 471 THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 472 473 16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN 474 WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY 475 AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU 476 FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR 477 CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE 478 LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING 479 RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A 480 FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF 481 SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 482 DAMAGES. 483 484 END OF TERMS AND CONDITIONS 485 487 How to Apply These Terms to Your New Libraries 488 489 If you develop a new library, and you want it to be of the greatest 490 possible use to the public, we recommend making it free software that 491 everyone can redistribute and change. You can do so by permitting 492 redistribution under these terms (or, alternatively, under the terms of the 493 ordinary General Public License). 494 495 To apply these terms, attach the following notices to the library. It is 496 safest to attach them to the start of each source file to most effectively 497 convey the exclusion of warranty; and each file should have at least the 498 "copyright" line and a pointer to where the full notice is found. 499 500 <one line to give the library's name and a brief idea of what it does.> 501 Copyright (C) <year> <name of author> 502 503 This library is free software; you can redistribute it and/or 504 modify it under the terms of the GNU Lesser General Public 505 License as published by the Free Software Foundation; either 506 version 2.1 of the License, or (at your option) any later version. 507 508 This library is distributed in the hope that it will be useful, 509 but WITHOUT ANY WARRANTY; without even the implied warranty of 510 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 511 Lesser General Public License for more details. 512 513 You should have received a copy of the GNU Lesser General Public 514 License along with this library; if not, write to the Free Software 515 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 516 517 Also add information on how to contact you by electronic and paper mail. 518 519 You should also get your employer (if you work as a programmer) or your 520 school, if any, to sign a "copyright disclaimer" for the library, if 521 necessary. Here is a sample; alter the names: 522 523 Yoyodyne, Inc., hereby disclaims all copyright interest in the 524 library `Frob' (a library for tweaking knobs) written by James Random Hacker. 525 526 <signature of Ty Coon>, 1 April 1990 527 Ty Coon, President of Vice 528 529 That's all there is to it! 530