[FFmpeg-devel] [PATCH] Fix function parameters for rgb48 to YV12 functions.

Ramiro Polla ramiro.polla
Mon Jan 11 09:21:31 CET 2010


On Mon, Jan 11, 2010 at 6:14 AM, Zuxy Meng <zuxy.meng at gmail.com> wrote:
> 2010/1/11 Ramiro Polla <ramiro.polla at gmail.com>:
>> $subj
>>
>
> Why do we have to use long to replace int? We support larger "width"
> under 64 bit machines?

Have you never had to resize a 5 billion pixels wide image? =)

It's because of the optimized assembly functions. If the parameters
are long, they can be used directly by both x86_32 and x86_64 asm. But
that's an issue for mingw-w64, which has long the same size as int.
Maybe the parameters should all be int, and the optimized functions
should declare a local x86_reg variable to access, but that might mean
one more memory access for them...



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