Hardware encoders(Quicksync/NVENC) colormatrix behavior

[poisondeathray]

You're correct, that was lack of nv12 conversion. Wasn't FFMpeg doing NV12 conversion automatically for nvenc before? I always used it without specify nv12 and i dont remember it caused issue in past.

Maybe you didn't look closely enough. If your really interested go download some old binaries and check

It also depends what decoder was used and how you sent the data. For Nvidia GPU decode , it always sends NV12 directly anyways (you could have some other steps in between that alter this). SW and most generic YUV 4:2:0 input will be -pix_fmt yuv420p by default

[chummy02]

I have another thing to try understand better. Color primaries and Transfer characteristics. I made some research and found some old threads with good info about that. I understand than transfer is almost useless but primaries can be used in some few cases like quicktime or HDTV. So when i do colormatrix or scale fileter matrix conversion, does it convert all those parameters or only matrix coefficient? Zscale specify those values separated for conversion differently from others.

I mean, because when i do those conversions these filters dont flag video output automatically, i need to manually insert those values with (-color_primaries, -color_trc, -colorspace) to flag output video file.