What exactly is done by CPU\VideoCard\iGPU

[AndrewTheGreat]

Hi, I recently upgraded to an iGPU processor from a non-iGPU one. Running the same projects I made I cannot say there's any noticeable impact on performance in Premiere Pro with the iGPU present in my system.

The question is: where can I find information about what exactly is cumputed\encoded\decoded\rendered by the CPU alone an what - by the GPU and iGPU?

Right now my projects in Premiere Pro 24 (comprise 1080 \ 4k h264 and movs from Iphone, Sony, DJI and Insta360 cameras, as well as GPU and no-GPU accelerated effects, transitions like FilmImpact, Premiere Composer and AtomX, colorgrading, text transribation, different animated essential graphisc presets) still utilize the same amount of CPU (100% most of the time) with the iGPU loaded not more than 20% or idle most of the time, and my GPU - by 40-60% depending on the amount of GPU-hungry effects on the timeline. The footage alone never loads my iGPU more than 40% and most of the time does not load it at all

i7 14700k, RTX 4080

[R Neil Haugen]

What gets used and when can be a complex thing as it depends both on the things on that GPU accelerated list, and on the processing order of effects in the sequence involved. Sizing changes and color/tonal things are GPU most of the time, and depending on a whole host of factors some long-GOP encoding can be either sent to GPU or kept by the CPU.

All two-pass encoding is by the GPU manufacturer's requirements "software only", meaning totally on the CPU.

[AndrewTheGreat]

So no use in iGPU then?

[RjL190365]

There is some, but not a lot. And some of the footage that you're working with forces everything onto the CPU no matter which software you're using to edit.

The biggest difference you'll se is in 10-bit 4:2:2 HEVC footage (which you apparently are not using at the moment), where only the iGPU (in your case) currently supports for hardware decoding. Nvidia currently supports only 4:2:0 or 4:4:4 for HEVC decoding and encoding but not 4:2:2; however, Adobe currently does not permit H.264 or HEVC exports in anything other than 4:2:0 even with software-only encoding.

[AndrewTheGreat]

And what about h264 ? And more importanly - why is this support not implemented? Are there any hardwarewise limitations?

[RjL190365]

Hardware limitations dictated by the GPU manufacturers themselves, as I mentioned many times. Nvidia, AMD and Intel just don't care about h.264 any more as they all treat it as a "legacy" codec at this point.

[AndrewTheGreat]

Well, another day - another discovery. Today learned that the mediocre tiktok-oriented software CapCut can utilize Intel iGPU to decode h265 12 bit 444 and the professional software Premiere Pro can NOT. Bummer