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 Author: Firebrandx [ Wed Jul 05, 2017 11:00 am ] Post subject: Question concerning the "Overscan" page: My question concerns the following line of the section called "For Emulator Developers":But as a slight optimization, you can scale first (256 * 8/7 = 292) and then pad: stretch the 256x240 pixels to 292x240, 584x480, 876x720, or 1168x960 square pixels or 320x240 or 640x480 non-square pixels. Isn't it better math to use scaling before correction? For example, say you want to scale to 4x. My formula for that is (256 * 4) * (8/7), which gives 1170 pixels, not 1168. It adds in that extra bit of accuracy in my opinion to scale before correction, not correct before scaling.

 Author: tepples [ Wed Jul 05, 2017 11:27 am ] Post subject: Re: Question concerning the "Overscan" page: I think I chose the multiples of 292 because 292 is a multiple of 4, making 1168 a multiple of 16.The difference between the two is 1.1406:1 (292/256) as opposed to 1.1429:1 (true PAR).

 Author: Firebrandx [ Wed Jul 05, 2017 4:56 pm ] Post subject: Re: Question concerning the "Overscan" page: tepples wrote:I think I chose the multiples of 292 because 292 is a multiple of 4, making 1168 a multiple of 16.The difference between the two is 1.1406:1 (292/256) as opposed to 1.1429:1 (true PAR).I see, so in the case of digital scaling, 1168 makes each pixel integer scaled, though a hair less accurate than scaling before correcting.On the Framemeister, the horizontal axis is averaged on pixel edges, so 1170 looks just as smooth as any other width.

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