Commit Graph

14 Commits

Author SHA1 Message Date
Diego Biurrun
25f613f8be dca: Move syncword definitions to a separate header 2015-03-04 13:29:33 +01:00
Diego Biurrun
f8c1719771 dca: Remove separate header for DCA ExSS
There is no point in having a separate header for a single declaration.
2015-02-16 10:44:56 +01:00
Diego Biurrun
b339019de4 dca: Split code for handling the EXSS extension off into a separate file 2015-02-14 10:13:49 -08:00
Diego Biurrun
1db6a080bd dca: Move ff_dca_convert_bitstream() to the DCA common code
This makes the DCA parser and decoder independent.
2013-03-27 14:21:45 +01:00
Martin Storsjö
d66c52c2b3 Add support for building shared libraries with MSVC
This requires the makedef perl script by Derek, from the
c89-to-c99 repo. That scripts produces a .def file, listing
the symbols to be exported, based on the gcc version scripts
and the built object files.

To properly load non-function symbols from DLL files, the
data symbol declarations need to have the attribute
__declspec(dllimport) when building the calling code. (On mingw,
the linker can fix this up automatically, which is why it has not
been an issue so far. If this attribute is omitted, linking
actually succeeds, but reads from the table will not produce the
desired results at runtime.)

MSVC seems to manage to link DLLs (and run properly) even if
this attribute is present while building the library itself
(which normally isn't recommended) - other object files in the
same library manage to link to the symbol (with a small warning
at link time, like "warning LNK4049: locally defined symbol
_avpriv_mpa_bitrate_tab imported" - it doesn't seem to be possible
to squelch this warning), and the definition of the tables
themselves produce a warning that can be squelched ("warning C4273:
'avpriv_mpa_bitrate_tab' : inconsistent dll linkage, see previous
definition of 'avpriv_mpa_bitrate_tab').

In this setup, mingw isn't able to link object files that refer to
data symbols with __declspec(dllimport) without those symbols
actually being linked via a DLL (linking avcodec.dll ends up with
errors like "undefined reference to `__imp__avpriv_mpa_freq_tab'").
The dllimport declspec isn't needed at all in mingw, so we simply
choose not to declare it for other compilers than MSVC that requires
it. (If ICL support later requires it, the condition can be extended
later to include both of them.)

This also implies that code that is built to link to a certain
library as a DLL can't link to the same library as a static library.
Therefore, we only allow building either static or shared but not
both at the same time. (That is, static libraries as such can be,
and actually are, built - this is used for linking the test tools to
internal symbols in the libraries - but e.g. libavformat built to
link to libavcodec as a DLL cannot link statically to libavcodec.)

Also, linking to DLLs is slightly different from linking to shared
libraries on other platforms. DLLs use a thing called import
libraries, which is basically a stub library allowing the linker
to know which symbols exist in the DLL and what name the DLL will
have at runtime.

In mingw/gcc, the import library is usually named libfoo.dll.a,
which goes next to a static library named libfoo.a. This allows
gcc to pick the dynamic one, if available, from the normal -lfoo
switches, just as it does for libfoo.a vs libfoo.so on Unix. On
MSVC however, you need to literally specify the name of the import
library instead of the static library.

Signed-off-by: Martin Storsjö <martin@martin.st>
2012-10-18 14:26:15 +03:00
Diego Biurrun
19cf7163c1 dca: Switch dca_sample_rates to avpriv_ prefix; it is used across libs 2012-08-01 11:43:31 +02:00
Diego Biurrun
9e4bca16f8 dca: Move tables used outside of dcadec.c to a separate file. 2012-08-01 00:17:17 +02:00
Mans Rullgard
2912e87a6c Replace FFmpeg with Libav in licence headers
Signed-off-by: Mans Rullgard <mans@mansr.com>
2011-03-19 13:33:20 +00:00
Kostya Shishkov
d041a59897 Add support for parsing and decoding DCA-HD streams.
Originally committed as revision 15951 to svn://svn.ffmpeg.org/ffmpeg/trunk
2008-11-29 10:06:37 +00:00
Stefano Sabatini
987903826b Globally rename the header inclusion guard names.
Consistently apply this rule: the guard name is obtained from the
filename by stripping the leading "lib", converting '/' and '.'  to
'_' and uppercasing the resulting name. Guard names in the root
directory have to be prefixed by "FFMPEG_".

Originally committed as revision 15120 to svn://svn.ffmpeg.org/ffmpeg/trunk
2008-08-31 07:39:47 +00:00
Diego Biurrun
5b21bdabe4 Add FFMPEG_ prefix to all multiple inclusion guards.
Originally committed as revision 10765 to svn://svn.ffmpeg.org/ffmpeg/trunk
2007-10-17 09:37:46 +00:00
Guillaume Poirier
efb775777f add a comment to indicate which #endif belong to which #define
Originally committed as revision 9356 to svn://svn.ffmpeg.org/ffmpeg/trunk
2007-06-17 18:59:28 +00:00
Måns Rullgård
699b3f99d0 add multiple inclusion guards to headers
Originally committed as revision 9345 to svn://svn.ffmpeg.org/ffmpeg/trunk
2007-06-17 00:01:30 +00:00
Diego Biurrun
98c98e04cc Move dca parser to its own file.
Originally committed as revision 8881 to svn://svn.ffmpeg.org/ffmpeg/trunk
2007-05-03 23:50:24 +00:00