Reply To: Capture Sizing and Aspect Ratio

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Sure you can, afai understand it. Everything in the table is in relation to the pixel clock defined by Rec.601, 6.14 MHz for square pixels in 4:3 aspect ratio. So divide by the dot clock of the console and you get the console PAR.
NES: 6.14/5.37 = 8:7
Saturn: 6.14/7.16 = 6:7

Of course can’t use the rounded numbers to get the exact ratios, but you get the idea.

PS Actually I don’t know if the ”6.14 MHz for square pixels” was defined directly in Rec.601 (never read it), but it checks out when compared to the pixel clock of 480i video, where it’s 13.5 MHz for 858 samples with 10:11 PAR. (13.5*10/11)/2 = 6.14. (divided by two since it has double horizontal resolution compared to 240p)
So 858 samples for 704×480 -> 780 samples for square pixel 640×480 -> 390 samples for 320×240.