Closed SiV44 closed 1 year ago
1.
bt709->GBR->bt2020nc
is correct. To apply transfer and prim conversion, RGB colorformat (GBR) is required instead of YUV format (yuv444), so first conversion to GBR is applied,
2. There is always a matrix conversion, as lut is applied to RGB colorformat (GBR), not YUV colorformat (yuv444).
bt709->GBR->bt2020nc
is correct. To apply transfer and prim conversion, RGB colorformat (GBR) is required instead of YUV >format (yuv444), so first conversion to GBR is applied,
So the conversion is correct and the output will always be darker?
There is always a matrix conversion, as lut is applied to RGB colorformat (GBR), not YUV colorformat (yuv444).
What if the input is 10-bit bt2020, not 8-bit bt709, will it not affect the colorimetry?
So the conversion is correct and the output will always be darker?
Yes, the conversion is correct. QSVEnc does not have sdr2hdr tonemapping, so it is not possible to convert to sdr from hdr, so the output will be darker.
lut requires RGB anyway, so conversion is always required. I don't know the case of 10-bit bt2020.
Hello rigaya
Using colorspace conversion (from bt709 to bt2020)
--vpp-colorspace matrix=bt709:bt2020nc,colorprim=bt709:bt2020,transfer=bt709:bt2020-10
Output looks like this:![Sony Sushi UHD HFR SDR BT2020 Demo mp4_snapshot_00 13 000](https://github.com/rigaya/QSVEnc/assets/60115682/0f843f26-90e3-489b-a776-3df2c0e725b3)
Input for comparison:![Sony Sushi UHD HFR SDR BT709 Demo mkv_snapshot_00 13 000](https://github.com/rigaya/QSVEnc/assets/60115682/4714837a-b5e5-49f2-9881-d89c3e4857bb)
Output is much darker. Shouldn't the matrix conversion be linear?
bt709->linear->bt2020nc
instead ofbt709->GBR->bt2020nc
Second thing is conversion using LUT3D
--vpp-colorspace lut3d="C:\K_TONE Vintage_KODACHROME.cube",lut3d_interp=tetrahedral
There is always a matrix conversion.
Thanks for your time, Ragards