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higherpurpose

How come there's no 64-bit version yet? Wouldn't that improve performance for something like video-decoding?

Also, it's disappointing to see there's still no native (and automatic) subtitle-seeking feature.

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> How come there's no 64-bit version yet?

The 64-bit Windows binary is getting deployed on the mirror right now.

> Wouldn't that improve performance for something like video-decoding?

64-bit is a tradeoff for video, less CPU usage, but more memory pressure, so the improvements are usually limited... It's more important to have good hardware acceleration, than 64bits.

> Also, it's disappointing to see there's still no native (and automatic) subtitle-seeking feature.

It's a new feature of 2.2.0

What I want to know is if QuickSync support is available on the Mac version of vlc.

No, this is a 3.0.0 feature.

x86-64 is such an ABI improvement over x86-32 that it's always 10-20% faster, even with the larger size pointers. Win64's ABI is a little worse than other platforms for libavcodec, since it has some callee-saved SSE registers and everyone else is caller-saved, but still true.

Hardware decoding is much more important for power savings than anything else.

Most standard video decoding code uses CPU feature detection and hand-optimized ASM for important bits, so x86-64 doesn't really add anything worthwhile for most video players and encoders - most of the magic is done in SSE/AVX codepaths anyway.

I think astrange knows what he's talking about considering he wrote chunks of those encoders and decoders.

And x86-64 turns those 8 SSE registers into 16! Those handwritten assembly paths are much easier when you don't have to write stack spills.

Hmm, you have a point there - x64 does make writing ASM significantly easier.

For most stuff, 64-bit makes surprisingly little difference. And it adds the complexity of needing to release two versions or an installer with both in it, which increases your bandwidth. VLC only uses about 5% CPU on my i7 to play a 1080p AC3 video. For most end user stuff, the difference of 64-bit is unnoticeable, a 1-2 % difference maybe. For certain things, it matters. Things like encoding or compression. Compressing files in 7-Zip can see a 5 to 10% increase in speed, for instance. If you routinely compress a lot of files that take minutes to package, it can be noticeable and add up.

  :~$ file `which vlc`
  /usr/bin/vlc: ELF 64-bit LSB  executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.24, BuildID[sha1]=XXXXX, stripped

Was there a specific reason you stripped the BuildID?

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