64 bit FFmpeg

I've been following the FFmpeg mailing list and it looks like compiling a 64 bit version of FFmpeg with MMX enabled is possible under OS X.

I compiled FFmpeg against head and ran a benchmark of the 32 bit version against the 64 bit version with The Greatest Game AVC trailer as a benchmark.

(ffmpeg --benchmark -i TheGreatestGame_HD_AVC.mp4 -f null -an /dev/null)

I'm happy to report that under this particular case there was a speed increase of approximately ~%5. XBMC for OS X already requires OS X 10.5 and in Intel processor. Are there any barriers to making XBMC a full 64 bit application?

Here's some additional info to compile a 64 bit version of FFmpeg:

Patch 1 for x86_64 MANGLE on OS X

Patch 2 for enabling x86_64 arch (not accepted and will probably be done in a different way but this works for our purpose for now):

FFmpeg configure options:
./configure --extra-cflags=-m64 --extra-ldflags=-m64 --arch=x86_64

CABAC patch against FFMpeg head (there was a couple of minor symbol changes)

exousir Wrote:CABAC patch against FFMpeg head (there was a couple of minor symbol changes)

Should this CABAC patch not first be submitted upstream to FFmpeg first?
http://ffmpeg.mplayerhq.hu/mailinglists.html
http://www.mplayerhq.hu/DOCS/tech/patches.txt

it has already been rejected there so save yourself the sorrow (and flames)

spiff Wrote:it has already been rejected there so save yourself the sorrow (and flames)

I've mentioned it here since XMBC for OS X is using it for current builds.

I should mention that the patch isn't my work, I just did a minor change to it so it could be used against head, should someone want to.

yah, i'm aware. just saving you the trouble of submitting it to ffmpeg

is it possible to build XBMC for 32-bit but have it use 64-bit DVDPlayer (which includes 64-bit FFmpeg)?

...I was thinking as the XBMC GUI will probably not benefit for being 64-bit it would be great if the 32-bit XBMC (GUI) would use use both 32-bit and 64-bit DVDPlayer, and come with both, and auto-detect which processor-type it runs on so it knows which DVDPlayer it should use (the 32-bit DVDPlayer or the 64-bit DVDPlayer). That way the same XBMC for Mac OS X would be compatible with both 32-bit and 64-bit processors, and be able to benefit when it is installed on a Mac with a 64-bit processor.

If possible then the same principle should be possible for XBMC for Linux and for Windows as well, right?

you cannot load 64 bits library and embed them into a 32 bit binary. simply not possible

not even if all .so (Mac OS X and Linux 'DLL' files) under \XBMC\system\players\ are available in 64-bit?

nope. as i said you CANNOT embed 64bit code into a 32 bit binary. as long as the main program is 32 bit all you can load is 32 bit libraries.

Thanks for the help with the 64-bit binary building.

How can I include liba52/xvid? If I can't compile them for 64-bit arch, can I still use them?