Quality of the finished video

[shotcut]

@st599

lossless codecs are “visually lossless” not lossless

That’s not correct and confusing. ffv1, huffyuv, utvideo are truly lossless assuming no additional chroma subsampling is used.

[afan]

@RilosVideos

O.k. - i understand what you mean. When using lossy compression for encoding you will always have slightly more losses on every encoding you do as each picture and GOP are compressed anew. If you just want to do some very simple editing, e.g. cutting pieces out, you can use a tool that works on the original codec without any new losses but using the same codec. Its called “LosslessCut” - and works like the name suggests You have to get used to it, i think there is only a dos-version for the command-window.

Anyway you can use lossless codecs for intermediate steps, so if you want to save an intermediate result and check the effect of some filters, this is the way to go without any additional losses. But you will get huge file sizes, as the compression will be minimal. If you have finalized your editing you will finally export it in some good compression codec with some slight losses but medium file size.

I guess you could do up to 10 exports with lossy codec and quality of 55-60% without seeing much difference. If you go below this quality setting you will start to see artefacts. So its all a compromise of file size, practicability (e.g. decoding speed on standard computer) and quality.

Thanks.

[st599]

Apologies, I was meaning codecs often described as lossless such as ProRes, DNxHD etc.
But even with Yuv, you will end up with losses caused by quantisation unless floating point is used throughout the conversion.