Reply To: Dreamcast – VGA or DTV 480p confusion

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Hi people, I’m brand-new to the boards here, I’m in the USA with all NTSC-USA equipment, and I’m trying to figure out how to get properly proportioned graphics out of my Sega Dreamcast setup, primarily in 16:9 widescreen. That’s why my name is RoundCircleS. I will mention now that my TV set offers no useful aspect ratio adjustments at all, beyond selecting 16:9 or 4:3. I know that possibly besides composite input, Dreamcast won’t look right on any 4:3 screen without horizontal stretch adjustment, or if the original image is simply up-scaled to 16:9, and I think I sort of understand why this has always been a problem, and I think what you have come up with in the OSSC might be a solution. Please correct me wherever I am wrong or fill in the blanks because it would be nice to know why this has always been a problem for Dreamcast.

***Current setup is:

Dreamcast > S-Video cable (480i out) > Samsung TV model : LN-46-A650

From what I can see, this setup stretches the displayed image vertically in 4:3 mode (Ryo too thin) since Dreamcast outputs the S-video in (I am guessing here) “480i ITU-R Rec. 601” which is 3:2, and Segas solution is to paint black bars of specific pixel widths overlaying existing graphics on either side of the image, send it all out at 3:2, let all of it get squashed when the TV rectifies the 3:2 4:3 conflict as probably dictated by the standard, with the expectation that the end-user with a 4:3 set would simply horizontally stretch (not zoom) the image until the black bars on the left and right sides disappeared to re-gain the proper aspect ratio & image proportions. So from what I can gather, basically anyone looking at a 4:3 display showing Dreamcast through S-Video or VGA who does not have this manual/automatic adjustment somewhere on the set or in the game, won’t be looking at a display with proper proportions. My setup also can upscale the 4:3 image to 16:9, but then it squashes the image vertically (Ryo now too wide), I’m guessing since the original 3:2 image is not displayed correctly in 4:3 to begin with anyway, it just upscales the presented image to 16:9 and it works out getting screwed up again, but now in the opposite direction.

***Next step regardless:
Dreamcast > VGA cable > Samsung LN-46-A650 (TV has actual VGA-in and 3.5mm sound input tied to the VGA input)
This will give me 480p for the time being, but now the Dreamcast is outputting (I am guessing here) 480p 59.94, which is again 3:2. Again Sega paints the black bars over existing graphics, knowing how the 4:3 displays will re-fit the 3:2 image to 4:3 to appease the standard, and knowing that most monitors and even a lot of TVs (back then) had adjustments for stretching the picture and doing all sorts of things to the picture, so they assumed that most people back then would have just stretched (not zoomed) the image back out horizontally to cover the black bars on the left and right sides, and end up with a full 640×480 screen and most importantly, proper proportions! Unfortunately, my TV today does not do that!

***Looking around, I don’t see much out there. It seems like Framemeister might be what I want, but there’s no actual VGA plug input (You can input VGA through a component adaptor), and the horizontal scaling function seems maybe a little hit-or-miss. I don’t know, I’m not really sold on the Framemeister yet, but I am still checking into it.

***Possible better solution than Framemeister:

Dreamcast > VGA cable > OSSC outputting in 640×480 480p “digital video” mode> DVI-D -to- HDMI cable > Samsung LN-46-A650

I am thinking that I can use OSSC and take advantage of the 480p “digital video” mode, and connect it to my TV using the TVs HDMI input set to DVI input, allowing me to scale whatever shows up in 4:3/480p to 16:9, and finally end up with objects being displayed in proper proportion. I know that the 480p-DV standard allows for real-world flexibility between 4:3, 3:2, and 16:9 aspect ratios. Seems like the OSSC developer possibly realized about the Dreamcast outputting in 3:2, possibly realized that widescreen TVs don’t have tons of picture adjustments like back in the day, and possibly realized the problems that these conditions presented. That’s why I’m thinking that this might be the best solution, but I really have no idea.

Also, can I post a question asking about OSSC and specific TV compatibility in that specific thread, or is that only for posting test results? I’m wondering if anyone has tried what I want to do with the OSSC with my model of TV yet, and if it works.