Reply To: Dreamcast – VGA or DTV 480p confusion


The OSSC will only output 480i on 480i passthrough mode.


The DTV-480p setting is just for sampling the correct amount of horizontal pixels.

Somehow I started to think that using that setting, or perhaps using a dvi to hdmi cable, would cause the 480p signal to change to 480i. I think I confused myself while reading about the various video standards, possibly reading about DTV standards or something. My main concern is that I still have 480p getting to the TV with my proposed setup, and the OSSC set to DTV-480p.

Is it correct to think that the DC hangs those black sidebars over the 720×480 rendered graphics and then sends all of that to the TV as 720x480p without changing the pixel aspect ratio, and then the 3:4 TV squishes it, black bars and all, and that is the first time the pixel aspect ratio gets affected?

You are correct except that it renders at 640×480 and pads it to 720×480 with black bars.

Ok, let me see if I am getting some of this. Using a hypothetical setup of DC> vga cable > 3:4 CRT TV. The original image is stored in 720×480 of some pixel aspect ratio, the DC takes that info and changes it when it renders it in 640×480 (does that change the original pixel aspect ratio?), then it places the bars on either side of that, and that whole thing is output to the TV as a 720×480 image of some pixel aspect ratio, and then the TV changes the pixel aspect ratio at that point when it displays all of that in 3:4 640×480? So the pixel aspect ratio possibly changes at least twice (and maybe more) by the time it is actually displayed and before the end-user changes it again? I guess I am wanting to know what the pixel aspect ratios are within the DC, and exactly how may times they might change, and what it is by the time the VGA signal is exiting the DC.

What do you mean with the DV standard that you need to set for widescreen? You just need to set your tv to 16:9 with a widescreen game.

Sorry, not sure what got lost, I was asking the question specifically in terms of using the OSSC in the setup. DC > vga cable > OSSC DTV 480p > dvi-hdmi cable > my TV, set to 16:9. Just looking for clarification if the OSSC definitely helps fix the aspect ratio problems with those specific games.
Also I was asking if I would have any issues that would affect the aspect ratio if I were running Shenmue2 UK-PAL on that same setup.

(Also just to clarify, none of those games are what I would call widescreen games. although F-355 does have an in-game widescreen option, it also shows up incorrectly in 3:4 and 16:9 on my tv in S-Video, and from what I understand, that in-game widescreen option disappears once the DC goes to VGA output. I have not tested that but my VGA cable should be here any day now and that is what I expect to happen there.)