[exousir]

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)

[Gamester17]

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

[spiff]

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

[exousir]

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.

[spiff]

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

[Gamester17]

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?

[spiff]

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

[Gamester17]

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

[spiff]

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.

[dizziness]

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?

[Halligalli]

Last time I checked, you can compile a program in Mac OS X for both 32 and 64-bit arch by using universal binaries. The same way it is possible to have one binary that works on PPC, PPC64, x86 and x86_64.

[davilla]

ffmpeg is not the problem with a 64-bit XBMC for Mac,

see http://trac.macports.org/wiki/SnowLeopardProblems

we rely heavily on MacPorts and it's very borked for 10.6.