I have created a new project with two video clips. One video clip was encoded as 4K (3840x2160@~39Mbps) MP4. The second clip was encoded as 1080P@~9Mbps MP4. I have have adjusted the two clips to be the same size within a new project (3840x2160).
Question 1: When I encode this new video at 3840x2160, how does Adobe Premiere handle the lower quality video clip? Does it average the YUV to in effect upconvert it? Does it leave it native and the 4K native, yet maintain the edited resolution? Understanding this would be helpful.
Question 2: Depending on the answer to the first question, is there a way to maintain the intrinsic quality levels of both videos yet changing the scale of the 1080P video?
Thank you in advance for the feedback.
1. This depends on what you've done with the clip in the sequence. If you scaled it, then PP will apply a scaling algorithm to the 1080 for the 4K output. Which one depends on a few factors.
2. No. You lose quality when scaling, so assuming you want to see the entire image without any surrounding black, one of them will be degraded. Having said that, the degradation of the 4K outputting to 1080 will be much less noticeable than upscaling the 1080 to 4K.