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Comment by IntelMiner | Hacker News Reader

What's the point of using Vulkan as an encoding API if the work is still being done on the CPU then? I'm not sure I understand

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No, no, it's done on GPU.

Isn't Nvenc (and its equivalents) based on using a specific ASIC on the GPU, rather than Vulkan which (as I understand it?) is just "regular" GPU compute?

Most GPU encoders are part ASIC, part regular GPGPU compute. That's what allowed AMD to increase the quality of their encoders via a driver update, but also why you can't add easily add entirely new codecs.

That said, outside of GPUs there are both FPGA-based and pure-ASIC hardware encoders that beat not just NVENC but even software encoding in terms of quality AND performance, such as AMD's Alveo lineup. https://www.amd.com/en/products/accelerators/alveo/ma35d.htm...

No, Vulkan has released a standard API for video encoding/decoding[1]. So you can use that to access the hardware rather than the proprietary APIs like nvenc.

[1]: https://www.khronos.org/assets/uploads/apis/Vulkan-Video-Dee...

The Vulkan APi calls out to the same hardware. The benefit of using it via Vulkan is that you (in theory) don’t need to have multiple APIs for different GPU vendors.

It's also meant to make it (somewhat) easier to apply various GPGPU filters and scalers before encode or after decode, like HDR tonemapping. The OS usually has some method to do this while keeping the data in the GPU VRAM by passing a handle from one API subsystem to another but if it never leaves Vulkan you don't have to worry about getting that right.

The Vulkan API is just a common way to access NVENC and its AMD and Intel alternatives.

Which is very nifty. Part of the reason for me still being on Windows is that it gives you a common API to hardware encoders.

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