Lower transcoding Speed than expected?

[Antonbp5]

Hello All.

I just got a new machine because my old one was relatively outdated, and couldn't run windows 11.
The now one has a i5-1135G7 with Irix XE iGPU. The old one had an i5-7500 with a HD 630.


I have attached 4 Transcoding logs, but I will TLDR them here:

It seems that I am getting a negligible Performance boost in WaterWorld 4K. An upgrade from 69 to 77 FPS.
But in Butchers Crossing at 1080p, I go from 250~ to 380~ Which is almost a 50% performance increase.

Can anyone see in my logs why the 4K performance is so "poor" compared to what I have read that this iGPU should be able to do?

Thank you very much.

ps: The only difference in their setup, is going from windows 10 to 11, Faster Ram, and of course the CPU. It is the exact same files played from the exact same device over the exact same network.

[bitmap]

If I recall correctly, when transcoding an HDR video you will get HDR --> SDR, tonemapped by your CPU rather than the iGPU. This would explain the improvement (better CPU) but the lack of significantly higher performance (tonemapping happens w/ CPU, not GPU).

ETA: My Arc A380 gets those numbers when encoding to AV1 and HWA with this card is a massive improvement over an iGPU.

[TheDreadPirate]

Your 4K video is HDR10. Meaning that during a transcode it is also tone mapped. Tone mapping is VRAM limited. Since this is an iGPU it is using your system RAM and the RAM in your new setup is likely not that much faster than the old setup.

[Antonbp5]

Your 4K video is HDR10.  Meaning that during a transcode it is also tone mapped.  Tone mapping is VRAM limited.  Since this is an iGPU it is using your system RAM and the RAM in your new setup is likely not that much faster than the old setup.

Oh okay very cool. So it isn't actually the resolution, it is just the HDR10 part. Very cool. The performance is still good and very usable of course. Just found it odd, as my sources said it would be incredible performance.

Thank you very much!

---

If I recall correctly, when transcoding an HDR video you will get HDR --> SDR, tonemapped by your CPU rather than the iGPU. This would explain the improvement (better CPU) but the lack of significantly higher performance (tonemapping happens w/ CPU, not GPU).

ETA: My Arc A380 gets those numbers when encoding to AV1 and HWA with this card is a massive improvement over an iGPU.

I just tested it and going from 0 sessions to 1 4K HDR session used 2 GB of Ram and CPU bumped to about 30%. So seems like a mix of of RAM and CPU. Very cool. Good thing I only own one 4K movie.

Thank you very much.