There is a way to get highly accurate YUV -> RGB color conversion.
You can test it on a yuv video.
ffmpeg -i <YUV_Source> -vf zscale=min=709,format=gbrp -vframes 1 out.png
Since PNG is always in RGB format, the conversion to PNG will always be to RGB, and that filter I used fixes the inaccurate color conversion in most cases.
But how do I fix the color conversion from RGB to YUV? When ever I convert RGB source material to YUV everything has a greenish or yellowish tint to it and some colors are way off.
So if I wanted to, say, convert that PNG created with the above command back to YUV while still retaining the correct colors, how would I do that?