Maybe the latest Premiere or After Effects on Windows with a Pascal GPU or something, so you get DXVA decode. I doubt you'd be able to get real mezz quality with x264 at less than 50% the bitrate of ProRes 4444.īut either way, you're losing compatibility with a whole lot of tools and workflows. H.264 would be quite a bit higher, as it isn't as efficient for 4k (only 8x8 blocks, while HEVC does up to 32x32) and no -cu-lossless, which actually can reduce bitrate by finding blocks that are small encoded losslessly that would be bigger as quantized lossy. In my tests (getting on a year old), With medium-GOP I was able t get similar quality to ProRes 4444 at 25% the bitrate, and with IDR-only at about 40% the bitrate. Yeah, the compatibility hit is so bad you might as well use HEVC, which can be a lot more efficient for near-lossless mezzanine encoding. You might be better off using ProRes 4444 or DNxHR for this. Unless this is just for archival, you will probably have issues with compatibility.

Avanti ffmpeg tutorial prores