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Re:WASM 3.0 Completed by gertop on Wednesday September 17, 2025 @06:09PM (#45281972)
> 4GiB of completely uncompressed 1080p video in memory is only 86 frames

How is that data stored?

Because (2^32)÷(1920×1080×4) = 518 which is still low but not 86 so I'm curious what I'm missing?

Re:WASM 3.0 Completed by brokencube on Wednesday September 17, 2025 @06:39PM (#45282277)
I would guess 3 colour channels at 16bit (i.e. 2 bytes)

(2^32)÷(1920×1080×4×3×2) = 86

Re:WASM 3.0 Completed by TheBicPen on Thursday September 18, 2025 @01:25AM (#45285769)
Where does the 4 come from? I thought it was R+G+B+A, but you already have 3 colour channels in that calculation
Re:WASM 3.0 Completed by brokencube on Thursday September 18, 2025 @05:39AM (#45287595)
Yep, my logic is faulty there. And even if we assume that it's 24bpp color, that's still a factor of 2 out.
Re:WASM 3.0 Completed by 05 on Wednesday September 17, 2025 @06:32PM (#45282215)
Apparently with 24 bytes per pixel instead of bits :) Although to be fair, there's HDR+ and DV, so probably 4(RGBA/YUVA) floats per pixel, which is pretty close..
Re:WASM 3.0 Completed by jjcm on Wednesday September 17, 2025 @09:09PM (#45283650)
> How is that data stored?

So glad you asked. It's stored poorly because I'm bad at maths and I'm mixing up bits and bytes.

That's what I get for posting on HN while in a meeting.