doc/developer.texi
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 \input texinfo @c -*- texinfo -*-
 
 @settitle Developer Documentation
 @titlepage
 @center @titlefont{Developer Documentation}
 @end titlepage
 
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 @top
 
 @contents
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 @chapter Developers Guide
 
 @section API
 @itemize @bullet
 @item libavcodec is the library containing the codecs (both encoding and
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 decoding). Look at @file{doc/examples/decoding_encoding.c} to see how to use
 it.
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 @item libavformat is the library containing the file format handling (mux and
 demux code for several formats). Look at @file{ffplay.c} to use it in a
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 player. See @file{doc/examples/muxing.c} to use it to generate audio or video
 streams.
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 @end itemize
 
 @section Integrating libavcodec or libavformat in your program
 
 You can integrate all the source code of the libraries to link them
 statically to avoid any version problem. All you need is to provide a
 'config.mak' and a 'config.h' in the parent directory. See the defines
 generated by ./configure to understand what is needed.
 
 You can use libavcodec or libavformat in your commercial program, but
 @emph{any patch you make must be published}. The best way to proceed is
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 to send your patches to the FFmpeg mailing list.
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 @section Contributing
 
 There are 3 ways by which code gets into ffmpeg.
 @itemize @bullet
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 @item Submitting Patches to the main developer mailing list
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       see @ref{Submitting patches} for details.
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 @item Directly committing changes to the main tree.
 @item Committing changes to a git clone, for example on github.com or
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       gitorious.org. And asking us to merge these changes.
 @end itemize
 
 Whichever way, changes should be reviewed by the maintainer of the code
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 before they are committed. And they should follow the @ref{Coding Rules}.
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 The developer making the commit and the author are responsible for their changes
 and should try to fix issues their commit causes.
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 @anchor{Coding Rules}
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 @section Coding Rules
 
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 @subsection Code formatting conventions
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 There are the following guidelines regarding the indentation in files:
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 @itemize @bullet
 @item
 Indent size is 4.
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 @item
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 The TAB character is forbidden outside of Makefiles as is any
 form of trailing whitespace. Commits containing either will be
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 rejected by the git repository.
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 @item
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 You should try to limit your code lines to 80 characters; however, do so if
 and only if this improves readability.
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 @end itemize
 The presentation is one inspired by 'indent -i4 -kr -nut'.
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 The main priority in FFmpeg is simplicity and small code size in order to
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 minimize the bug count.
 
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 @subsection Comments
 Use the JavaDoc/Doxygen  format (see examples below) so that code documentation
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 can be generated automatically. All nontrivial functions should have a comment
 above them explaining what the function does, even if it is just one sentence.
 All structures and their member variables should be documented, too.
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 Avoid Qt-style and similar Doxygen syntax with @code{!} in it, i.e. replace
 @code{//!} with @code{///} and similar.  Also @@ syntax should be employed
 for markup commands, i.e. use @code{@@param} and not @code{\param}.
 
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 @example
 /**
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  * @@file
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  * MPEG codec.
  * @@author ...
  */
 
 /**
  * Summary sentence.
  * more text ...
  * ...
  */
 typedef struct Foobar@{
     int var1; /**< var1 description */
     int var2; ///< var2 description
     /** var3 description */
     int var3;
 @} Foobar;
 
 /**
  * Summary sentence.
  * more text ...
  * ...
  * @@param my_parameter description of my_parameter
  * @@return return value description
  */
 int myfunc(int my_parameter)
 ...
 @end example
 
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 @subsection C language features
 
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 FFmpeg is programmed in the ISO C90 language with a few additional
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 features from ISO C99, namely:
 @itemize @bullet
 @item
 the @samp{inline} keyword;
 @item
 @samp{//} comments;
 @item
 designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
 @item
 compound literals (@samp{x = (struct s) @{ 17, 23 @};})
 @end itemize
 
 These features are supported by all compilers we care about, so we will not
 accept patches to remove their use unless they absolutely do not impair
 clarity and performance.
 
 All code must compile with recent versions of GCC and a number of other
 currently supported compilers. To ensure compatibility, please do not use
 additional C99 features or GCC extensions. Especially watch out for:
 @itemize @bullet
 @item
 mixing statements and declarations;
 @item
 @samp{long long} (use @samp{int64_t} instead);
 @item
 @samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
 @item
 GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
 @end itemize
 
 @subsection Naming conventions
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 All names should be composed with underscores (_), not CamelCase. For example,
 @samp{avfilter_get_video_buffer} is an acceptable function name and
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 @samp{AVFilterGetVideo} is not. The exception from this are type names, like
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 for example structs and enums; they should always be in the CamelCase
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 There are the following conventions for naming variables and functions:
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 @itemize @bullet
 @item
 For local variables no prefix is required.
 @item
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 For file-scope variables and functions declared as @code{static}, no prefix
 is required.
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 @item
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 For variables and functions visible outside of file scope, but only used
 internally by a library, an @code{ff_} prefix should be used,
 e.g. @samp{ff_w64_demuxer}.
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 @item
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 For variables and functions visible outside of file scope, used internally
 across multiple libraries, use @code{avpriv_} as prefix, for example,
 @samp{avpriv_aac_parse_header}.
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 @item
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 Each library has its own prefix for public symbols, in addition to the
 commonly used @code{av_} (@code{avformat_} for libavformat,
 @code{avcodec_} for libavcodec, @code{swr_} for libswresample, etc).
 Check the existing code and choose names accordingly.
 Note that some symbols without these prefixes are also exported for
 retro-compatibility reasons. These exceptions are declared in the
 @code{lib<name>/lib<name>.v} files.
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 @end itemize
 
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 Furthermore, name space reserved for the system should not be invaded.
 Identifiers ending in @code{_t} are reserved by
 @url{http://pubs.opengroup.org/onlinepubs/007904975/functions/xsh_chap02_02.html#tag_02_02_02, POSIX}.
 Also avoid names starting with @code{__} or @code{_} followed by an uppercase
 letter as they are reserved by the C standard. Names starting with @code{_}
 are reserved at the file level and may not be used for externally visible
 symbols. If in doubt, just avoid names starting with @code{_} altogether.
 
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 @subsection Miscellaneous conventions
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 @itemize @bullet
 @item
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 fprintf and printf are forbidden in libavformat and libavcodec,
 please use av_log() instead.
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 @item
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 Casts should be used only when necessary. Unneeded parentheses
 should also be avoided if they don't make the code easier to understand.
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 @end itemize
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 @subsection Editor configuration
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 In order to configure Vim to follow FFmpeg formatting conventions, paste
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 the following snippet into your @file{.vimrc}:
 @example
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 " indentation rules for FFmpeg: 4 spaces, no tabs
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 set expandtab
 set shiftwidth=4
 set softtabstop=4
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 set cindent
 set cinoptions=(0
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 " Allow tabs in Makefiles.
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 autocmd FileType make,automake set noexpandtab shiftwidth=8 softtabstop=8
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 " Trailing whitespace and tabs are forbidden, so highlight them.
 highlight ForbiddenWhitespace ctermbg=red guibg=red
 match ForbiddenWhitespace /\s\+$\|\t/
 " Do not highlight spaces at the end of line while typing on that line.
 autocmd InsertEnter * match ForbiddenWhitespace /\t\|\s\+\%#\@@<!$/
 @end example
 
 For Emacs, add these roughly equivalent lines to your @file{.emacs.d/init.el}:
 @example
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 (c-add-style "ffmpeg"
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              '("k&r"
                (c-basic-offset . 4)
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                (indent-tabs-mode . nil)
                (show-trailing-whitespace . t)
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                (c-offsets-alist
                 (statement-cont . (c-lineup-assignments +)))
                )
              )
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 (setq c-default-style "ffmpeg")
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 @end example
 
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 @section Development Policy
 
 @enumerate
 @item
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    Contributions should be licensed under the
    @uref{http://www.gnu.org/licenses/lgpl-2.1.html, LGPL 2.1},
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    including an "or any later version" clause, or, if you prefer
    a gift-style license, the
    @uref{http://www.isc.org/software/license/, ISC} or
    @uref{http://mit-license.org/, MIT} license.
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    @uref{http://www.gnu.org/licenses/gpl-2.0.html, GPL 2} including
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    an "or any later version" clause is also acceptable, but LGPL is
    preferred.
 @item
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    You must not commit code which breaks FFmpeg! (Meaning unfinished but
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    enabled code which breaks compilation or compiles but does not work or
    breaks the regression tests)
    You can commit unfinished stuff (for testing etc), but it must be disabled
    (#ifdef etc) by default so it does not interfere with other developers'
    work.
 @item
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    The commit message should have a short first line in the form of
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    a @samp{topic: short description} as a header, separated by a newline
    from the body consisting of an explanation of why the change is necessary.
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    If the commit fixes a known bug on the bug tracker, the commit message
    should include its bug ID. Referring to the issue on the bug tracker does
    not exempt you from writing an excerpt of the bug in the commit message.
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 @item
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    You do not have to over-test things. If it works for you, and you think it
    should work for others, then commit. If your code has problems
    (portability, triggers compiler bugs, unusual environment etc) they will be
    reported and eventually fixed.
 @item
    Do not commit unrelated changes together, split them into self-contained
    pieces. Also do not forget that if part B depends on part A, but A does not
    depend on B, then A can and should be committed first and separate from B.
    Keeping changes well split into self-contained parts makes reviewing and
    understanding them on the commit log mailing list easier. This also helps
    in case of debugging later on.
    Also if you have doubts about splitting or not splitting, do not hesitate to
    ask/discuss it on the developer mailing list.
 @item
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    Do not change behavior of the programs (renaming options etc) or public
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    API or ABI without first discussing it on the ffmpeg-devel mailing list.
    Do not remove functionality from the code. Just improve!
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    Note: Redundant code can be removed.
 @item
    Do not commit changes to the build system (Makefiles, configure script)
    which change behavior, defaults etc, without asking first. The same
    applies to compiler warning fixes, trivial looking fixes and to code
    maintained by other developers. We usually have a reason for doing things
    the way we do. Send your changes as patches to the ffmpeg-devel mailing
    list, and if the code maintainers say OK, you may commit. This does not
    apply to files you wrote and/or maintain.
 @item
    We refuse source indentation and other cosmetic changes if they are mixed
    with functional changes, such commits will be rejected and removed. Every
    developer has his own indentation style, you should not change it. Of course
    if you (re)write something, you can use your own style, even though we would
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    prefer if the indentation throughout FFmpeg was consistent (Many projects
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    force a given indentation style - we do not.). If you really need to make
    indentation changes (try to avoid this), separate them strictly from real
    changes.
 
    NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
    then either do NOT change the indentation of the inner part within (do not
    move it to the right)! or do so in a separate commit
 @item
    Always fill out the commit log message. Describe in a few lines what you
    changed and why. You can refer to mailing list postings if you fix a
    particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
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    Recommended format:
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    area changed: Short 1 line description
 
    details describing what and why and giving references.
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 @item
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    Make sure the author of the commit is set correctly. (see git commit --author)
    If you apply a patch, send an
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    answer to ffmpeg-devel (or wherever you got the patch from) saying that
    you applied the patch.
 @item
    When applying patches that have been discussed (at length) on the mailing
    list, reference the thread in the log message.
 @item
     Do NOT commit to code actively maintained by others without permission.
     Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
     timeframe (12h for build failures and security fixes, 3 days small changes,
     1 week for big patches) then commit your patch if you think it is OK.
     Also note, the maintainer can simply ask for more time to review!
 @item
     Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
     are sent there and reviewed by all the other developers. Bugs and possible
     improvements or general questions regarding commits are discussed there. We
     expect you to react if problems with your code are uncovered.
 @item
     Update the documentation if you change behavior or add features. If you are
     unsure how best to do this, send a patch to ffmpeg-devel, the documentation
     maintainer(s) will review and commit your stuff.
 @item
     Try to keep important discussions and requests (also) on the public
     developer mailing list, so that all developers can benefit from them.
 @item
     Never write to unallocated memory, never write over the end of arrays,
     always check values read from some untrusted source before using them
     as array index or other risky things.
 @item
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     Remember to check if you need to bump versions for the specific libav*
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     parts (libavutil, libavcodec, libavformat) you are changing. You need
     to change the version integer.
     Incrementing the first component means no backward compatibility to
     previous versions (e.g. removal of a function from the public API).
     Incrementing the second component means backward compatible change
     (e.g. addition of a function to the public API or extension of an
     existing data structure).
     Incrementing the third component means a noteworthy binary compatible
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     change (e.g. encoder bug fix that matters for the decoder). The third
     component always starts at 100 to distinguish FFmpeg from Libav.
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 @item
     Compiler warnings indicate potential bugs or code with bad style. If a type of
     warning always points to correct and clean code, that warning should
     be disabled, not the code changed.
     Thus the remaining warnings can either be bugs or correct code.
     If it is a bug, the bug has to be fixed. If it is not, the code should
     be changed to not generate a warning unless that causes a slowdown
     or obfuscates the code.
 @item
     If you add a new file, give it a proper license header. Do not copy and
     paste it from a random place, use an existing file as template.
 @end enumerate
 
 We think our rules are not too hard. If you have comments, contact us.
 
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 @anchor{Submitting patches}
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 @section Submitting patches
 
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 First, read the @ref{Coding Rules} above if you did not yet, in particular
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 the rules regarding patch submission.
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 When you submit your patch, please use @code{git format-patch} or
 @code{git send-email}. We cannot read other diffs :-)
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 Also please do not submit a patch which contains several unrelated changes.
 Split it into separate, self-contained pieces. This does not mean splitting
 file by file. Instead, make the patch as small as possible while still
 keeping it as a logical unit that contains an individual change, even
 if it spans multiple files. This makes reviewing your patches much easier
 for us and greatly increases your chances of getting your patch applied.
 
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 Use the patcheck tool of FFmpeg to check your patch.
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 The tool is located in the tools directory.
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 Run the @ref{Regression tests} before submitting a patch in order to verify
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 it does not cause unexpected problems.
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 It also helps quite a bit if you tell us what the patch does (for example
 'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
 and has no lrint()')
 
 Also please if you send several patches, send each patch as a separate mail,
 do not attach several unrelated patches to the same mail.
 
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 Patches should be posted to the
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 @uref{http://lists.ffmpeg.org/mailman/listinfo/ffmpeg-devel, ffmpeg-devel}
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 mailing list. Use @code{git send-email} when possible since it will properly
 send patches without requiring extra care. If you cannot, then send patches
 as base64-encoded attachments, so your patch is not trashed during
 transmission.
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 Your patch will be reviewed on the mailing list. You will likely be asked
 to make some changes and are expected to send in an improved version that
 incorporates the requests from the review. This process may go through
 several iterations. Once your patch is deemed good enough, some developer
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 will pick it up and commit it to the official FFmpeg tree.
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 Give us a few days to react. But if some time passes without reaction,
 send a reminder by email. Your patch should eventually be dealt with.
 
 
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 @section New codecs or formats checklist
 
 @enumerate
 @item
     Did you use av_cold for codec initialization and close functions?
 @item
     Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
     AVInputFormat/AVOutputFormat struct?
 @item
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     Did you bump the minor version number (and reset the micro version
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     number) in @file{libavcodec/version.h} or @file{libavformat/version.h}?
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 @item
     Did you register it in @file{allcodecs.c} or @file{allformats.c}?
 @item
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     Did you add the AVCodecID to @file{avcodec.h}?
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     When adding new codec IDs, also add an entry to the codec descriptor
     list in @file{libavcodec/codec_desc.c}.
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 @item
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     If it has a FourCC, did you add it to @file{libavformat/riff.c},
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     even if it is only a decoder?
 @item
     Did you add a rule to compile the appropriate files in the Makefile?
     Remember to do this even if you're just adding a format to a file that is
     already being compiled by some other rule, like a raw demuxer.
 @item
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     Did you add an entry to the table of supported formats or codecs in
     @file{doc/general.texi}?
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 @item
     Did you add an entry in the Changelog?
 @item
     If it depends on a parser or a library, did you add that dependency in
     configure?
 @item
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     Did you @code{git add} the appropriate files before committing?
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 @item
     Did you make sure it compiles standalone, i.e. with
     @code{configure --disable-everything --enable-decoder=foo}
     (or @code{--enable-demuxer} or whatever your component is)?
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 @end enumerate
 
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 @section patch submission checklist
 
 @enumerate
 @item
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     Does @code{make fate} pass with the patch applied?
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 @item
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     Was the patch generated with git format-patch or send-email?
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 @item
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     Did you sign off your patch? (git commit -s)
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     See @url{http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=blob_plain;f=Documentation/SubmittingPatches} for the meaning
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     of sign off.
 @item
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     Did you provide a clear git commit log message?
 @item
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     Is the patch against latest FFmpeg git master branch?
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 @item
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     Are you subscribed to ffmpeg-devel?
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     (the list is subscribers only due to spam)
 @item
     Have you checked that the changes are minimal, so that the same cannot be
     achieved with a smaller patch and/or simpler final code?
 @item
     If the change is to speed critical code, did you benchmark it?
 @item
     If you did any benchmarks, did you provide them in the mail?
 @item
     Have you checked that the patch does not introduce buffer overflows or
     other security issues?
 @item
     Did you test your decoder or demuxer against damaged data? If no, see
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     tools/trasher, the noise bitstream filter, and
     @uref{http://caca.zoy.org/wiki/zzuf, zzuf}. Your decoder or demuxer
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     should not crash, end in a (near) infinite loop, or allocate ridiculous
     amounts of memory when fed damaged data.
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 @item
     Does the patch not mix functional and cosmetic changes?
 @item
     Did you add tabs or trailing whitespace to the code? Both are forbidden.
 @item
     Is the patch attached to the email you send?
 @item
     Is the mime type of the patch correct? It should be text/x-diff or
     text/x-patch or at least text/plain and not application/octet-stream.
 @item
     If the patch fixes a bug, did you provide a verbose analysis of the bug?
 @item
     If the patch fixes a bug, did you provide enough information, including
     a sample, so the bug can be reproduced and the fix can be verified?
     Note please do not attach samples >100k to mails but rather provide a
     URL, you can upload to ftp://upload.ffmpeg.org
 @item
     Did you provide a verbose summary about what the patch does change?
 @item
     Did you provide a verbose explanation why it changes things like it does?
 @item
     Did you provide a verbose summary of the user visible advantages and
     disadvantages if the patch is applied?
 @item
     Did you provide an example so we can verify the new feature added by the
     patch easily?
 @item
     If you added a new file, did you insert a license header? It should be
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     taken from FFmpeg, not randomly copied and pasted from somewhere else.
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 @item
     You should maintain alphabetical order in alphabetically ordered lists as
     long as doing so does not break API/ABI compatibility.
 @item
     Lines with similar content should be aligned vertically when doing so
     improves readability.
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 @item
     Consider to add a regression test for your code.
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 @item
     If you added YASM code please check that things still work with --disable-yasm
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 @item
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     Make sure you check the return values of function and return appropriate
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     error codes. Especially memory allocation functions like @code{av_malloc()}
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     are notoriously left unchecked, which is a serious problem.
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 @item
     Test your code with valgrind and or Address Sanitizer to ensure it's free
     of leaks, out of array accesses, etc.
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 @end enumerate
 
 @section Patch review process
 
 All patches posted to ffmpeg-devel will be reviewed, unless they contain a
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 clear note that the patch is not for the git master branch.
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 Reviews and comments will be posted as replies to the patch on the
 mailing list. The patch submitter then has to take care of every comment,
 that can be by resubmitting a changed patch or by discussion. Resubmitted
 patches will themselves be reviewed like any other patch. If at some point
 a patch passes review with no comments then it is approved, that can for
 simple and small patches happen immediately while large patches will generally
 have to be changed and reviewed many times before they are approved.
 After a patch is approved it will be committed to the repository.
 
 We will review all submitted patches, but sometimes we are quite busy so
 especially for large patches this can take several weeks.
 
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 If you feel that the review process is too slow and you are willing to try to
 take over maintainership of the area of code you change then just clone
 git master and maintain the area of code there. We will merge each area from
 where its best maintained.
 
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 When resubmitting patches, please do not make any significant changes
 not related to the comments received during review. Such patches will
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 be rejected. Instead, submit significant changes or new features as
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 separate patches.
 
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 @anchor{Regression tests}
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 @section Regression tests
 
 Before submitting a patch (or committing to the repository), you should at least
 test that you did not break anything.
 
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 Running 'make fate' accomplishes this, please see @url{fate.html} for details.
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 [Of course, some patches may change the results of the regression tests. In
 this case, the reference results of the regression tests shall be modified
 accordingly].
 
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 @subsection Adding files to the fate-suite dataset
 
 When there is no muxer or encoder available to generate test media for a
 specific test then the media has to be inlcuded in the fate-suite.
 First please make sure that the sample file is as small as possible to test the
 respective decoder or demuxer sufficiently. Large files increase network
 bandwidth and disk space requirements.
 Once you have a working fate test and fate sample, provide in the commit
 message or introductionary message for the patch series that you post to
 the ffmpeg-devel mailing list, a direct link to download the sample media.
 
 
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 @subsection Visualizing Test Coverage
 
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 The FFmpeg build system allows visualizing the test coverage in an easy
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 manner with the coverage tools @code{gcov}/@code{lcov}.  This involves
 the following steps:
 
 @enumerate
 @item
     Configure to compile with instrumentation enabled:
     @code{configure --toolchain=gcov}.
 @item
     Run your test case, either manually or via FATE. This can be either
     the full FATE regression suite, or any arbitrary invocation of any
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     front-end tool provided by FFmpeg, in any combination.
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 @item
     Run @code{make lcov} to generate coverage data in HTML format.
 @item
     View @code{lcov/index.html} in your preferred HTML viewer.
 @end enumerate
 
 You can use the command @code{make lcov-reset} to reset the coverage
 measurements. You will need to rerun @code{make lcov} after running a
 new test.
 
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 @subsection Using Valgrind
 
 The configure script provides a shortcut for using valgrind to spot bugs
 related to memory handling. Just add the option
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 @code{--toolchain=valgrind-memcheck} or @code{--toolchain=valgrind-massif}
 to your configure line, and reasonable defaults will be set for running
 FATE under the supervision of either the @strong{memcheck} or the
 @strong{massif} tool of the valgrind suite.
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 In case you need finer control over how valgrind is invoked, use the
 @code{--target-exec='valgrind <your_custom_valgrind_options>} option in
 your configure line instead.
 
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 @anchor{Release process}
 @section Release process
 
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 FFmpeg maintains a set of @strong{release branches}, which are the
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 recommended deliverable for system integrators and distributors (such as
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 Linux distributions, etc.). At regular times, a @strong{release
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 manager} prepares, tests and publishes tarballs on the
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 @url{http://ffmpeg.org} website.
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 There are two kinds of releases:
 
 @enumerate
 @item
     @strong{Major releases} always include the latest and greatest
     features and functionality.
 @item
     @strong{Point releases} are cut from @strong{release} branches,
     which are named @code{release/X}, with @code{X} being the release
     version number.
 @end enumerate
 
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 Note that we promise to our users that shared libraries from any FFmpeg
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 release never break programs that have been @strong{compiled} against
 previous versions of @strong{the same release series} in any case!
 
 However, from time to time, we do make API changes that require adaptations
 in applications. Such changes are only allowed in (new) major releases and
 require further steps such as bumping library version numbers and/or
 adjustments to the symbol versioning file. Please discuss such changes
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 on the @strong{ffmpeg-devel} mailing list in time to allow forward planning.
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 @anchor{Criteria for Point Releases}
 @subsection Criteria for Point Releases
 
 Changes that match the following criteria are valid candidates for
 inclusion into a point release:
 
 @enumerate
 @item
     Fixes a security issue, preferably identified by a @strong{CVE
     number} issued by @url{http://cve.mitre.org/}.
 @item
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     Fixes a documented bug in @url{https://trac.ffmpeg.org}.
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 @item
     Improves the included documentation.
 @item
     Retains both source code and binary compatibility with previous
     point releases of the same release branch.
 @end enumerate
 
 The order for checking the rules is (1 OR 2 OR 3) AND 4.
 
 
 @subsection Release Checklist
 
 The release process involves the following steps:
 
 @enumerate
 @item
     Ensure that the @file{RELEASE} file contains the version number for
     the upcoming release.
 @item
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     Add the release at @url{https://trac.ffmpeg.org/admin/ticket/versions}.
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 @item
     Announce the intent to do a release to the mailing list.
 @item
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     Make sure all relevant security fixes have been backported. See
     @url{https://ffmpeg.org/security.html}.
 @item
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     Ensure that the FATE regression suite still passes in the release
     branch on at least @strong{i386} and @strong{amd64}
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     (cf. @ref{Regression tests}).
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 @item
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     Prepare the release tarballs in @code{bz2} and @code{gz} formats, and
     supplementing files that contain @code{gpg} signatures
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 @item
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     Publish the tarballs at @url{http://ffmpeg.org/releases}. Create and
     push an annotated tag in the form @code{nX}, with @code{X}
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     containing the version number.
 @item
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     Propose and send a patch to the @strong{ffmpeg-devel} mailing list
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     with a news entry for the website.
 @item
     Publish the news entry.
 @item
     Send announcement to the mailing list.
 @end enumerate
 
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 @bye