NVENC RGB output is looking washed out while nv12 output is fine

I’m using d3d11 Nvenc api to encode the output from desktop duplication interface.

if i’m using nv12 format (converted using d3d11 video processor), output is looking as expected.

but rgb output is little washed out. my guess is the input was in limited range but nvenc assumed it’s fullrange. If so, how do i fix it? By editing SPS/PPS or is there an option in nvenc for me to set? I can post video samples via youtube if required

in case someone finds this later, It’s my mistake. dxgi video processor i was using to scale the images is doing this… configuring that fixed my issue.