For those people want hevc preview with hardware acceleration on linux+wayland with mesa driver (amd/intel)

[GRFTSOL]

TLDR:
Edit the .desktop file, change Exec to below:
Exec=losslesscut --enable-features=AcceleratedVideoDecodeLinuxGL,VaapiVideoDecodeLinuxGL,VaapiVideoDecoder,VaapiIgnoreDriverChecks,UseChromeOSDirectVideoDecoder,Vulkan,DefaultANGLEVulkan,VulkanFromANGLE

For those not WOOB linux distro like archlinux, before doing this, you need:

1. mesa driver, eg: mesa package on archlinux
2. vulkan driver, eg: vulkan-radeon package on archlinux, which is recommended on amdgpu currently.
3. ensure you don't have any other vulkan driver like amdvlk on archlinux, in case wrong driver choice by env

• If other package (eg: steam) need 32bit vulkan driver, you need to install lib32-vulkan-radeon, they are all belongs to RADV
• use ls /usr/share/vulkan/icd.d/ to confirm you have correct vulkan driver, for me on amdgpu, it should be radeon_icd.i686.json and radeon_icd.x86_64.json

4. Edit the .desktop file like above mentioned.

Reference:
https://wiki.archlinux.org/title/Chromium#Hardware_video_acceleration

Note

• If you really need an extra vulkan driver, please refer this: https://wiki.archlinux.org/title/Vulkan#Switching_between_AMD_drivers
• I don't have Nvidia gpu, but it should be similar, the key is arguments, nvidia driver should already contain vulkan support.
• Please ensure it contain at most one argument starting with --enable-features
• For me, latest release of lossless-cut is already wayland support, but if you are using old version, maybe you need to refer this: https://wiki.archlinux.org/title/Chromium#Native_Wayland_support to add arguments with running on wayland

How to tell if hwaccel is actually enabled:

1. Dev tools -> hamburger menu -> more tools -> media, check the decoder name, like the picture above.
2. Using nvtop, check the DEC engine usage, if you don't see DEC, means hwaccel not enabled.
3. Of course, see the video preview.

[mifi]

thanks i will add it to the faq