It is not that it is fixed, it is just that putting out a encoder that is good at PSNR and SSIM are like 10% of the work, actually getting that film grain right takes forever. That is if you care about these sort of things, other wise you can encode a Digitally Cleaned Video with x265 and get ~30% reduction in file size compared to x264.
It is not that it is fixed, it is just that putting out a encoder that is good at PSNR and SSIM are like 10% of the work, actually getting that film grain right takes forever. That is if you care about these sort of things, other wise you can encode a Digitally Cleaned Video with x265 and get ~30% reduction in file size compared to x264.