colorspace conversion

[hanaluluelle]

i've captured gameplay using nvenc lossless yuv444 via obs. i'm going to transcode this later on to lossy 420.

in theory, will the end product have better quality than if i just captured in lossless 420 then converted to lossy 420?

[SameSelf]

Probably not that big of a deal for gameplay unless you do a lot of post production. Capturing in 4:4:4 is analogous to shooting RAW on a DSLR, great if you have Photoshop and want to do a bunch of debayering, editing, and give your shots a unique style that is yours alone, something that is just not possible with a JPEG. But then, that bogs down the pipeline for content creators focused on just getting stuff out the door. The same can be said for 4:4:4 or 4:2:2 video versus 4:2:0.

[nixiejames]

i also want to know the answer to this.

i get that 4:4:4 is a good way to preserve quality but let's say i do a lot of editing and the end product is always going to be 420 then is 444 to 420 the better way to go rather than 420 to 420?

[poisondeathray]

i also want to know the answer to this.

i get that 4:4:4 is a good way to preserve quality but let's say i do a lot of editing and the end product is always going to be 420 then is 444 to 420 the better way to go rather than 420 to 420?

It depends on what type of "editing", what operations you are doing, and which editor

But if your record in YUV420, but use an editor that works in RGB, there will an additional step of upsampling / downsampling of the chroma channels, along with colorspace conversion losses. If you record in RGB, deliver in YUV420, there is only 1 downscale step (and 1 upscale back to RGB when you "see" it). The more times you resize up and down a picture it gets blurrier, right ? Because that's what's happening to the color information. The algorithm used to up/downscale also makes a difference, but in general things like thin text, sharp color edges will be degraded more noticable; so for video games things like HUD displays, counters. But on live action, "normal" footage, the lossess are not as noticable.

If you use an editor that can handle the input and work YUV420, and you're not doing any RGB manipulations (certain filters, certain color manipulations), there are no additional losses if you just do simple cuts. But for operations like reframing shots, zooming, the results will be worse because you're starting with less color information (1/2 width, 1/2 height)