[x265] Custom LowRes scale

[Nicolas Morey-Chaisemartin]

On 07/22/2014 10:08 AM, Steve Borho wrote:
> On 07/22, Nicolas Morey-Chaisemartin wrote:
>> I'll have a look at it. It doesn't semm as straight forward as the
>> other files though.
> it is slightly more complicated; you'll want to scale up the block sizes
> used for motion-compensated weight analysis - up to 32x32 or 64x64 based
> on how much further you downscale the lowres in lookahead.

Is there a clean way to get a LUMA_NNxNN value from a block size ?
Should I handle block larger than 64x64 by looping on the 64x64 blocks? or simply add a check at lowres init that the fullres CU size is <= 64 ?

>
>> While we're talking about lowres MV: from what I could gather they are
>> not used during the motionSearch on the full res picture.  As a lot of
>> time is spent finding those, whouldn't it be useful to add them as
>> candidate in the fullres search?
> This has been on my TODO list for ages; a couple of people have claimed
> they've tried it and it hasn't helped as much as you might think.  But I
> haven't had a working patch in hand to verify it.
>
> The AMVP fixup after motion search, where we get to go shopping for a
> better MVP after the search, often makes extra motion candidates
> superfluous.
>
I started working on this yesterday for our accelerator but I got carried away on lowres scaling.
I haven't any results yet but I'll post them as soon as I have some.
By the way, lowres MV are in lowres luma pixels right? So I'll need to scale the vector by 2 to get the full MV?

Nicolas