1 \input texinfo @c -*- texinfo -*-
2 @documentencoding UTF-8
4 @settitle Developer Documentation
6 @center @titlefont{Developer Documentation}
13 @chapter Developers Guide
15 @section Notes for external developers
17 This document is mostly useful for internal FFmpeg developers.
18 External developers who need to use the API in their application should
19 refer to the API doxygen documentation in the public headers, and
20 check the examples in @file{doc/examples} and in the source code to
21 see how the public API is employed.
23 You can use the FFmpeg libraries in your commercial program, but you
24 are encouraged to @emph{publish any patch you make}. In this case the
25 best way to proceed is to send your patches to the ffmpeg-devel
26 mailing list following the guidelines illustrated in the remainder of
29 For more detailed legal information about the use of FFmpeg in
30 external programs read the @file{LICENSE} file in the source tree and
31 consult @url{https://ffmpeg.org/legal.html}.
35 There are 3 ways by which code gets into FFmpeg.
37 @item Submitting patches to the main developer mailing list.
38 See @ref{Submitting patches} for details.
39 @item Directly committing changes to the main tree.
40 @item Committing changes to a git clone, for example on github.com or
41 gitorious.org. And asking us to merge these changes.
44 Whichever way, changes should be reviewed by the maintainer of the code
45 before they are committed. And they should follow the @ref{Coding Rules}.
46 The developer making the commit and the author are responsible for their changes
47 and should try to fix issues their commit causes.
52 @subsection Code formatting conventions
54 There are the following guidelines regarding the indentation in files:
61 The TAB character is forbidden outside of Makefiles as is any
62 form of trailing whitespace. Commits containing either will be
63 rejected by the git repository.
66 You should try to limit your code lines to 80 characters; however, do so if
67 and only if this improves readability.
70 K&R coding style is used.
72 The presentation is one inspired by 'indent -i4 -kr -nut'.
74 The main priority in FFmpeg is simplicity and small code size in order to
75 minimize the bug count.
78 Use the JavaDoc/Doxygen format (see examples below) so that code documentation
79 can be generated automatically. All nontrivial functions should have a comment
80 above them explaining what the function does, even if it is just one sentence.
81 All structures and their member variables should be documented, too.
83 Avoid Qt-style and similar Doxygen syntax with @code{!} in it, i.e. replace
84 @code{//!} with @code{///} and similar. Also @@ syntax should be employed
85 for markup commands, i.e. use @code{@@param} and not @code{\param}.
99 typedef struct Foobar @{
100 int var1; /**< var1 description */
101 int var2; ///< var2 description
102 /** var3 description */
110 * @@param my_parameter description of my_parameter
111 * @@return return value description
113 int myfunc(int my_parameter)
117 @subsection C language features
119 FFmpeg is programmed in the ISO C90 language with a few additional
120 features from ISO C99, namely:
124 the @samp{inline} keyword;
130 designated struct initializers (@samp{struct s x = @{ .i = 17 @};});
133 compound literals (@samp{x = (struct s) @{ 17, 23 @};}).
136 Implementation defined behavior for signed integers is assumed to match the
137 expected behavior for two's complement. Non representable values in integer
138 casts are binary truncated. Shift right of signed values uses sign extension.
141 These features are supported by all compilers we care about, so we will not
142 accept patches to remove their use unless they absolutely do not impair
143 clarity and performance.
145 All code must compile with recent versions of GCC and a number of other
146 currently supported compilers. To ensure compatibility, please do not use
147 additional C99 features or GCC extensions. Especially watch out for:
151 mixing statements and declarations;
154 @samp{long long} (use @samp{int64_t} instead);
157 @samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
160 GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
163 @subsection Naming conventions
164 All names should be composed with underscores (_), not CamelCase. For example,
165 @samp{avfilter_get_video_buffer} is an acceptable function name and
166 @samp{AVFilterGetVideo} is not. The exception from this are type names, like
167 for example structs and enums; they should always be in CamelCase.
169 There are the following conventions for naming variables and functions:
173 For local variables no prefix is required.
176 For file-scope variables and functions declared as @code{static}, no prefix
180 For variables and functions visible outside of file scope, but only used
181 internally by a library, an @code{ff_} prefix should be used,
182 e.g. @samp{ff_w64_demuxer}.
185 For variables and functions visible outside of file scope, used internally
186 across multiple libraries, use @code{avpriv_} as prefix, for example,
187 @samp{avpriv_report_missing_feature}.
190 Each library has its own prefix for public symbols, in addition to the
191 commonly used @code{av_} (@code{avformat_} for libavformat,
192 @code{avcodec_} for libavcodec, @code{swr_} for libswresample, etc).
193 Check the existing code and choose names accordingly.
194 Note that some symbols without these prefixes are also exported for
195 retro-compatibility reasons. These exceptions are declared in the
196 @code{lib<name>/lib<name>.v} files.
199 Furthermore, name space reserved for the system should not be invaded.
200 Identifiers ending in @code{_t} are reserved by
201 @url{http://pubs.opengroup.org/onlinepubs/007904975/functions/xsh_chap02_02.html#tag_02_02_02, POSIX}.
202 Also avoid names starting with @code{__} or @code{_} followed by an uppercase
203 letter as they are reserved by the C standard. Names starting with @code{_}
204 are reserved at the file level and may not be used for externally visible
205 symbols. If in doubt, just avoid names starting with @code{_} altogether.
207 @subsection Miscellaneous conventions
211 fprintf and printf are forbidden in libavformat and libavcodec,
212 please use av_log() instead.
215 Casts should be used only when necessary. Unneeded parentheses
216 should also be avoided if they don't make the code easier to understand.
219 @subsection Editor configuration
220 In order to configure Vim to follow FFmpeg formatting conventions, paste
221 the following snippet into your @file{.vimrc}:
223 " indentation rules for FFmpeg: 4 spaces, no tabs
229 " Allow tabs in Makefiles.
230 autocmd FileType make,automake set noexpandtab shiftwidth=8 softtabstop=8
231 " Trailing whitespace and tabs are forbidden, so highlight them.
232 highlight ForbiddenWhitespace ctermbg=red guibg=red
233 match ForbiddenWhitespace /\s\+$\|\t/
234 " Do not highlight spaces at the end of line while typing on that line.
235 autocmd InsertEnter * match ForbiddenWhitespace /\t\|\s\+\%#\@@<!$/
238 For Emacs, add these roughly equivalent lines to your @file{.emacs.d/init.el}:
240 (c-add-style "ffmpeg"
243 (indent-tabs-mode . nil)
244 (show-trailing-whitespace . t)
246 (statement-cont . (c-lineup-assignments +)))
249 (setq c-default-style "ffmpeg")
252 @section Development Policy
254 @subsection Patches/Committing
255 @subheading Licenses for patches must be compatible with FFmpeg.
256 Contributions should be licensed under the
257 @uref{http://www.gnu.org/licenses/lgpl-2.1.html, LGPL 2.1},
258 including an "or any later version" clause, or, if you prefer
259 a gift-style license, the
260 @uref{http://opensource.org/licenses/isc-license.txt, ISC} or
261 @uref{http://mit-license.org/, MIT} license.
262 @uref{http://www.gnu.org/licenses/gpl-2.0.html, GPL 2} including
263 an "or any later version" clause is also acceptable, but LGPL is
265 If you add a new file, give it a proper license header. Do not copy and
266 paste it from a random place, use an existing file as template.
268 @subheading You must not commit code which breaks FFmpeg!
269 This means unfinished code which is enabled and breaks compilation,
270 or compiles but does not work/breaks the regression tests. Code which
271 is unfinished but disabled may be permitted under-circumstances, like
272 missing samples or an implementation with a small subset of features.
273 Always check the mailing list for any reviewers with issues and test
274 FATE before you push.
276 @subheading Keep the main commit message short with an extended description below.
277 The commit message should have a short first line in the form of
278 a @samp{topic: short description} as a header, separated by a newline
279 from the body consisting of an explanation of why the change is necessary.
280 If the commit fixes a known bug on the bug tracker, the commit message
281 should include its bug ID. Referring to the issue on the bug tracker does
282 not exempt you from writing an excerpt of the bug in the commit message.
284 @subheading Testing must be adequate but not excessive.
285 If it works for you, others, and passes FATE then it should be OK to commit
286 it, provided it fits the other committing criteria. You should not worry about
287 over-testing things. If your code has problems (portability, triggers
288 compiler bugs, unusual environment etc) they will be reported and eventually
291 @subheading Do not commit unrelated changes together.
292 They should be split them into self-contained pieces. Also do not forget
293 that if part B depends on part A, but A does not depend on B, then A can
294 and should be committed first and separate from B. Keeping changes well
295 split into self-contained parts makes reviewing and understanding them on
296 the commit log mailing list easier. This also helps in case of debugging
298 Also if you have doubts about splitting or not splitting, do not hesitate to
299 ask/discuss it on the developer mailing list.
301 @subheading Ask before you change the build system (configure, etc).
302 Do not commit changes to the build system (Makefiles, configure script)
303 which change behavior, defaults etc, without asking first. The same
304 applies to compiler warning fixes, trivial looking fixes and to code
305 maintained by other developers. We usually have a reason for doing things
306 the way we do. Send your changes as patches to the ffmpeg-devel mailing
307 list, and if the code maintainers say OK, you may commit. This does not
308 apply to files you wrote and/or maintain.
310 @subheading Cosmetic changes should be kept in separate patches.
311 We refuse source indentation and other cosmetic changes if they are mixed
312 with functional changes, such commits will be rejected and removed. Every
313 developer has his own indentation style, you should not change it. Of course
314 if you (re)write something, you can use your own style, even though we would
315 prefer if the indentation throughout FFmpeg was consistent (Many projects
316 force a given indentation style - we do not.). If you really need to make
317 indentation changes (try to avoid this), separate them strictly from real
320 NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
321 then either do NOT change the indentation of the inner part within (do not
322 move it to the right)! or do so in a separate commit
324 @subheading Commit messages should always be filled out properly.
325 Always fill out the commit log message. Describe in a few lines what you
326 changed and why. You can refer to mailing list postings if you fix a
327 particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
331 area changed: Short 1 line description
333 details describing what and why and giving references.
336 @subheading Credit the author of the patch.
337 Make sure the author of the commit is set correctly. (see git commit --author)
338 If you apply a patch, send an
339 answer to ffmpeg-devel (or wherever you got the patch from) saying that
340 you applied the patch.
342 @subheading Complex patches should refer to discussion surrounding them.
343 When applying patches that have been discussed (at length) on the mailing
344 list, reference the thread in the log message.
346 @subheading Always wait long enough before pushing changes
347 Do NOT commit to code actively maintained by others without permission.
348 Send a patch to ffmpeg-devel. If no one answers within a reasonable
349 time-frame (12h for build failures and security fixes, 3 days small changes,
350 1 week for big patches) then commit your patch if you think it is OK.
351 Also note, the maintainer can simply ask for more time to review!
354 @subheading API/ABI changes should be discussed before they are made.
355 Do not change behavior of the programs (renaming options etc) or public
356 API or ABI without first discussing it on the ffmpeg-devel mailing list.
357 Do not remove widely used functionality or features (redundant code can be removed).
359 @subheading Remember to check if you need to bump versions for libav*.
360 Depending on the change, you may need to change the version integer.
361 Incrementing the first component means no backward compatibility to
362 previous versions (e.g. removal of a function from the public API).
363 Incrementing the second component means backward compatible change
364 (e.g. addition of a function to the public API or extension of an
365 existing data structure).
366 Incrementing the third component means a noteworthy binary compatible
367 change (e.g. encoder bug fix that matters for the decoder). The third
368 component always starts at 100 to distinguish FFmpeg from Libav.
370 @subheading Warnings for correct code may be disabled if there is no other option.
371 Compiler warnings indicate potential bugs or code with bad style. If a type of
372 warning always points to correct and clean code, that warning should
373 be disabled, not the code changed.
374 Thus the remaining warnings can either be bugs or correct code.
375 If it is a bug, the bug has to be fixed. If it is not, the code should
376 be changed to not generate a warning unless that causes a slowdown
377 or obfuscates the code.
379 @subheading Check untrusted input properly.
380 Never write to unallocated memory, never write over the end of arrays,
381 always check values read from some untrusted source before using them
382 as array index or other risky things.
384 @subsection Documentation/Other
385 @subheading Subscribe to the ffmpeg-cvslog mailing list.
386 It is important to do this as the diffs of all commits are sent there and
387 reviewed by all the other developers. Bugs and possible improvements or
388 general questions regarding commits are discussed there. We expect you to
389 react if problems with your code are uncovered.
391 @subheading Keep the documentation up to date.
392 Update the documentation if you change behavior or add features. If you are
393 unsure how best to do this, send a patch to ffmpeg-devel, the documentation
394 maintainer(s) will review and commit your stuff.
396 @subheading Important discussions should be accessible to all.
397 Try to keep important discussions and requests (also) on the public
398 developer mailing list, so that all developers can benefit from them.
400 @subheading Check your entries in MAINTAINERS.
401 Make sure that no parts of the codebase that you maintain are missing from the
402 @file{MAINTAINERS} file. If something that you want to maintain is missing add it with
404 If at some point you no longer want to maintain some code, then please help in
405 finding a new maintainer and also don't forget to update the @file{MAINTAINERS} file.
407 We think our rules are not too hard. If you have comments, contact us.
409 @section Code of conduct
411 Be friendly and respectful towards others and third parties.
412 Treat others the way you yourself want to be treated.
414 Be considerate. Not everyone shares the same viewpoint and priorities as you do.
415 Different opinions and interpretations help the project.
416 Looking at issues from a different perspective assists development.
418 Do not assume malice for things that can be attributed to incompetence. Even if
419 it is malice, it's rarely good to start with that as initial assumption.
421 Stay friendly even if someone acts contrarily. Everyone has a bad day
423 If you yourself have a bad day or are angry then try to take a break and reply
424 once you are calm and without anger if you have to.
426 Try to help other team members and cooperate if you can.
428 The goal of software development is to create technical excellence, not for any
429 individual to be better and "win" against the others. Large software projects
430 are only possible and successful through teamwork.
432 If someone struggles do not put them down. Give them a helping hand
433 instead and point them in the right direction.
435 Finally, keep in mind the immortal words of Bill and Ted,
436 "Be excellent to each other."
438 @anchor{Submitting patches}
439 @section Submitting patches
441 First, read the @ref{Coding Rules} above if you did not yet, in particular
442 the rules regarding patch submission.
444 When you submit your patch, please use @code{git format-patch} or
445 @code{git send-email}. We cannot read other diffs :-).
447 Also please do not submit a patch which contains several unrelated changes.
448 Split it into separate, self-contained pieces. This does not mean splitting
449 file by file. Instead, make the patch as small as possible while still
450 keeping it as a logical unit that contains an individual change, even
451 if it spans multiple files. This makes reviewing your patches much easier
452 for us and greatly increases your chances of getting your patch applied.
454 Use the patcheck tool of FFmpeg to check your patch.
455 The tool is located in the tools directory.
457 Run the @ref{Regression tests} before submitting a patch in order to verify
458 it does not cause unexpected problems.
460 It also helps quite a bit if you tell us what the patch does (for example
461 'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
464 Also please if you send several patches, send each patch as a separate mail,
465 do not attach several unrelated patches to the same mail.
467 Patches should be posted to the
468 @uref{https://lists.ffmpeg.org/mailman/listinfo/ffmpeg-devel, ffmpeg-devel}
469 mailing list. Use @code{git send-email} when possible since it will properly
470 send patches without requiring extra care. If you cannot, then send patches
471 as base64-encoded attachments, so your patch is not trashed during
472 transmission. Also ensure the correct mime type is used
473 (text/x-diff or text/x-patch or at least text/plain) and that only one
474 patch is inline or attached per mail.
475 You can check @url{https://patchwork.ffmpeg.org}, if your patch does not show up, its mime type
478 Your patch will be reviewed on the mailing list. You will likely be asked
479 to make some changes and are expected to send in an improved version that
480 incorporates the requests from the review. This process may go through
481 several iterations. Once your patch is deemed good enough, some developer
482 will pick it up and commit it to the official FFmpeg tree.
484 Give us a few days to react. But if some time passes without reaction,
485 send a reminder by email. Your patch should eventually be dealt with.
488 @section New codecs or formats checklist
492 Did you use av_cold for codec initialization and close functions?
495 Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
496 AVInputFormat/AVOutputFormat struct?
499 Did you bump the minor version number (and reset the micro version
500 number) in @file{libavcodec/version.h} or @file{libavformat/version.h}?
503 Did you register it in @file{allcodecs.c} or @file{allformats.c}?
506 Did you add the AVCodecID to @file{avcodec.h}?
507 When adding new codec IDs, also add an entry to the codec descriptor
508 list in @file{libavcodec/codec_desc.c}.
511 If it has a FourCC, did you add it to @file{libavformat/riff.c},
512 even if it is only a decoder?
515 Did you add a rule to compile the appropriate files in the Makefile?
516 Remember to do this even if you're just adding a format to a file that is
517 already being compiled by some other rule, like a raw demuxer.
520 Did you add an entry to the table of supported formats or codecs in
521 @file{doc/general.texi}?
524 Did you add an entry in the Changelog?
527 If it depends on a parser or a library, did you add that dependency in
531 Did you @code{git add} the appropriate files before committing?
534 Did you make sure it compiles standalone, i.e. with
535 @code{configure --disable-everything --enable-decoder=foo}
536 (or @code{--enable-demuxer} or whatever your component is)?
540 @section patch submission checklist
544 Does @code{make fate} pass with the patch applied?
547 Was the patch generated with git format-patch or send-email?
550 Did you sign off your patch? (git commit -s)
551 See @url{http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=blob_plain;f=Documentation/SubmittingPatches} for the meaning
555 Did you provide a clear git commit log message?
558 Is the patch against latest FFmpeg git master branch?
561 Are you subscribed to ffmpeg-devel?
562 (the list is subscribers only due to spam)
565 Have you checked that the changes are minimal, so that the same cannot be
566 achieved with a smaller patch and/or simpler final code?
569 If the change is to speed critical code, did you benchmark it?
572 If you did any benchmarks, did you provide them in the mail?
575 Have you checked that the patch does not introduce buffer overflows or
576 other security issues?
579 Did you test your decoder or demuxer against damaged data? If no, see
580 tools/trasher, the noise bitstream filter, and
581 @uref{http://caca.zoy.org/wiki/zzuf, zzuf}. Your decoder or demuxer
582 should not crash, end in a (near) infinite loop, or allocate ridiculous
583 amounts of memory when fed damaged data.
586 Did you test your decoder or demuxer against sample files?
587 Samples may be obtained at @url{https://samples.ffmpeg.org}.
590 Does the patch not mix functional and cosmetic changes?
593 Did you add tabs or trailing whitespace to the code? Both are forbidden.
596 Is the patch attached to the email you send?
599 Is the mime type of the patch correct? It should be text/x-diff or
600 text/x-patch or at least text/plain and not application/octet-stream.
603 If the patch fixes a bug, did you provide a verbose analysis of the bug?
606 If the patch fixes a bug, did you provide enough information, including
607 a sample, so the bug can be reproduced and the fix can be verified?
608 Note please do not attach samples >100k to mails but rather provide a
609 URL, you can upload to ftp://upload.ffmpeg.org.
612 Did you provide a verbose summary about what the patch does change?
615 Did you provide a verbose explanation why it changes things like it does?
618 Did you provide a verbose summary of the user visible advantages and
619 disadvantages if the patch is applied?
622 Did you provide an example so we can verify the new feature added by the
626 If you added a new file, did you insert a license header? It should be
627 taken from FFmpeg, not randomly copied and pasted from somewhere else.
630 You should maintain alphabetical order in alphabetically ordered lists as
631 long as doing so does not break API/ABI compatibility.
634 Lines with similar content should be aligned vertically when doing so
635 improves readability.
638 Consider adding a regression test for your code.
641 If you added YASM code please check that things still work with --disable-yasm.
644 Make sure you check the return values of function and return appropriate
645 error codes. Especially memory allocation functions like @code{av_malloc()}
646 are notoriously left unchecked, which is a serious problem.
649 Test your code with valgrind and or Address Sanitizer to ensure it's free
650 of leaks, out of array accesses, etc.
653 @section Patch review process
655 All patches posted to ffmpeg-devel will be reviewed, unless they contain a
656 clear note that the patch is not for the git master branch.
657 Reviews and comments will be posted as replies to the patch on the
658 mailing list. The patch submitter then has to take care of every comment,
659 that can be by resubmitting a changed patch or by discussion. Resubmitted
660 patches will themselves be reviewed like any other patch. If at some point
661 a patch passes review with no comments then it is approved, that can for
662 simple and small patches happen immediately while large patches will generally
663 have to be changed and reviewed many times before they are approved.
664 After a patch is approved it will be committed to the repository.
666 We will review all submitted patches, but sometimes we are quite busy so
667 especially for large patches this can take several weeks.
669 If you feel that the review process is too slow and you are willing to try to
670 take over maintainership of the area of code you change then just clone
671 git master and maintain the area of code there. We will merge each area from
672 where its best maintained.
674 When resubmitting patches, please do not make any significant changes
675 not related to the comments received during review. Such patches will
676 be rejected. Instead, submit significant changes or new features as
679 Everyone is welcome to review patches. Also if you are waiting for your patch
680 to be reviewed, please consider helping to review other patches, that is a great
681 way to get everyone's patches reviewed sooner.
683 @anchor{Regression tests}
684 @section Regression tests
686 Before submitting a patch (or committing to the repository), you should at least
687 test that you did not break anything.
689 Running 'make fate' accomplishes this, please see @url{fate.html} for details.
691 [Of course, some patches may change the results of the regression tests. In
692 this case, the reference results of the regression tests shall be modified
695 @subsection Adding files to the fate-suite dataset
697 When there is no muxer or encoder available to generate test media for a
698 specific test then the media has to be included in the fate-suite.
699 First please make sure that the sample file is as small as possible to test the
700 respective decoder or demuxer sufficiently. Large files increase network
701 bandwidth and disk space requirements.
702 Once you have a working fate test and fate sample, provide in the commit
703 message or introductory message for the patch series that you post to
704 the ffmpeg-devel mailing list, a direct link to download the sample media.
706 @subsection Visualizing Test Coverage
708 The FFmpeg build system allows visualizing the test coverage in an easy
709 manner with the coverage tools @code{gcov}/@code{lcov}. This involves
714 Configure to compile with instrumentation enabled:
715 @code{configure --toolchain=gcov}.
718 Run your test case, either manually or via FATE. This can be either
719 the full FATE regression suite, or any arbitrary invocation of any
720 front-end tool provided by FFmpeg, in any combination.
723 Run @code{make lcov} to generate coverage data in HTML format.
726 View @code{lcov/index.html} in your preferred HTML viewer.
729 You can use the command @code{make lcov-reset} to reset the coverage
730 measurements. You will need to rerun @code{make lcov} after running a
733 @subsection Using Valgrind
735 The configure script provides a shortcut for using valgrind to spot bugs
736 related to memory handling. Just add the option
737 @code{--toolchain=valgrind-memcheck} or @code{--toolchain=valgrind-massif}
738 to your configure line, and reasonable defaults will be set for running
739 FATE under the supervision of either the @strong{memcheck} or the
740 @strong{massif} tool of the valgrind suite.
742 In case you need finer control over how valgrind is invoked, use the
743 @code{--target-exec='valgrind <your_custom_valgrind_options>} option in
744 your configure line instead.
746 @anchor{Release process}
747 @section Release process
749 FFmpeg maintains a set of @strong{release branches}, which are the
750 recommended deliverable for system integrators and distributors (such as
751 Linux distributions, etc.). At regular times, a @strong{release
752 manager} prepares, tests and publishes tarballs on the
753 @url{https://ffmpeg.org} website.
755 There are two kinds of releases:
759 @strong{Major releases} always include the latest and greatest
760 features and functionality.
763 @strong{Point releases} are cut from @strong{release} branches,
764 which are named @code{release/X}, with @code{X} being the release
768 Note that we promise to our users that shared libraries from any FFmpeg
769 release never break programs that have been @strong{compiled} against
770 previous versions of @strong{the same release series} in any case!
772 However, from time to time, we do make API changes that require adaptations
773 in applications. Such changes are only allowed in (new) major releases and
774 require further steps such as bumping library version numbers and/or
775 adjustments to the symbol versioning file. Please discuss such changes
776 on the @strong{ffmpeg-devel} mailing list in time to allow forward planning.
778 @anchor{Criteria for Point Releases}
779 @subsection Criteria for Point Releases
781 Changes that match the following criteria are valid candidates for
782 inclusion into a point release:
786 Fixes a security issue, preferably identified by a @strong{CVE
787 number} issued by @url{http://cve.mitre.org/}.
790 Fixes a documented bug in @url{https://trac.ffmpeg.org}.
793 Improves the included documentation.
796 Retains both source code and binary compatibility with previous
797 point releases of the same release branch.
800 The order for checking the rules is (1 OR 2 OR 3) AND 4.
803 @subsection Release Checklist
805 The release process involves the following steps:
809 Ensure that the @file{RELEASE} file contains the version number for
810 the upcoming release.
813 Add the release at @url{https://trac.ffmpeg.org/admin/ticket/versions}.
816 Announce the intent to do a release to the mailing list.
819 Make sure all relevant security fixes have been backported. See
820 @url{https://ffmpeg.org/security.html}.
823 Ensure that the FATE regression suite still passes in the release
824 branch on at least @strong{i386} and @strong{amd64}
825 (cf. @ref{Regression tests}).
828 Prepare the release tarballs in @code{bz2} and @code{gz} formats, and
829 supplementing files that contain @code{gpg} signatures
832 Publish the tarballs at @url{https://ffmpeg.org/releases}. Create and
833 push an annotated tag in the form @code{nX}, with @code{X}
834 containing the version number.
837 Propose and send a patch to the @strong{ffmpeg-devel} mailing list
838 with a news entry for the website.
841 Publish the news entry.
844 Send an announcement to the mailing list.