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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



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.


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.


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


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.




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