So, how would you 2 propose replicating it in a real-world scenario? Thought I was hitting the mark, but apparently missed it. And if hitting the mark, and it adds to the evidence corroborating that it was MAME, well that's okay. I'm just concerned that using 60fps capture, both my direct feed and Jeremy's camera, isn't an accurate comparison.
If: The 1.047M video is a camera pointed at a screen
Then the best way to duplicate this scenario would be to point a video camera at a screen. One recording from actual DK screen and one from a PC screen running MAME fullscreen with -norotate and then compare the two results. If I recall, the VCR showed a "Volume ---" or some overlay showing that the bottom of the screen was to the left.
Then bottom of the camera would be at the left side of the DK playfield. A camcorder and VCR would record 60 fields per second, so no frames would be lost but the uploaded videos on youtube were downgraded to 30fps so half the frames were lost. Reencoding the 60 fps videos at 30 fps should simulate that degradation.
If: The 1.05M video is a vcr recording of a direct feed
Then this is compositionally identical to your 60fps recordings (except VCR has lower detail). The later conversion and upload to youtube downgraded it to 30fps so half of those frames were lost. Reencoding the 60fps video into 30fps would simulate the youtube degradation. Getting a MAME equivalent for comparison would require a video card with a composite video output and recording to a VCR. VCRs record at 60 fields per second so the closest duplication without actually owning a VCR would simply be an .avi recording directly from MAME (60fps) then reencoding that video into 30fps to simulate capturing video digitally and sending to youtube.
I think that would replicate equivalents for A:B comparisons