[RoundCircleS]

OK, I will have to buy a 2gb micro SD card & adapter so I can upgrade the FW and save the settings.

My TV does not seem to alter the image if I cycle the inputs on the TV, but I played around with the OSSC some more while using the DTV 480P input setting instead of “auto”/”VESA”.

480p Advanced Timing defaults & changes:

H Samplerate 858 (default) to 910
H Synclen 62 (default)
H Active 720 (default)
VActive 480 (default)
H Backporch 60 (default) to 100
V backporch 30 (Default) to 33

Adjusting the H Samplerate and the H backporch centered and stretched the image out to where the few vertical pixel columns on either side of the screen that the Dreamcast fades just a little are overscanned and are beyond the edge of my screen.
I adjusted the vertical backporch to raise the very bottom of the “shenmue clock” above the bottom edge of the screen.
I seemed to notice that adjusting these settings while using the DTV standard seems to re-size things on screen to maintain the aspect ratio, so the “shenmue clock” or shenmues on-screen buttons get larger all around, whereas stretching/re-centering the image though the Advanced Timing settings while using the VESA 640×480 input setting stretches the image horizontally a little.

[RoundCircleS]

I should have specified that I did save in the main menu, but the settings in advanced timing sub-menu did not stick.

Should I be able to save them with my loaded firmware? Or is this something that came along in later firmware?

Also, is it possible that it is not saving due to the OSSC blinking the red light as I adjust through the numbers that I mentioned above? It will blink once as I switch through each number. However, it also does this when I return to the default numbers, so it might be normal. To me the adjusted display looks just as good as what comes up as the default, but I also think that the red light might signify some sort of issue.

[RoundCircleS]

Hey, I answered my own questions, it looks like I need a remote to do this. Fortunately I have a Logitech Harmony 650 that I programmed and was able to go through the menus.

Sync Options -> H-PLL Post-Coast -> 1 lines

did the trick. (was set at 0) No more flickering! The other suggestion referring to the 480p-in settings did not stop the flickering.

Edit, thanks for the answer harrumph, I was typing this message while you answered and I did not see it until I posted.

[RoundCircleS]

Hi, first time running the DC through the OSSC, and I am having this flicker issue sometimes, usually with lighter colors and white. I want to try the couple of different settings above, but I’m not sure how to access the OSSC menus. FW is .73. Do I need a remote?

[RoundCircleS]

Hi BuckoA51, I got an e-mail confirming my subscription to the newsletter a couple days ago. Is a seperate invite to purchase the OSSC sent automatically or do I have to wait for some period of time?

[RoundCircleS]

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

Understood.

paul_bnl
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.

RoundCircleS
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?

paulb_nl
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.

paulb_nl
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.)

[RoundCircleS]

Ok I am learning that within the 480p DV standard, the 2:3 ratio is mainly a pixel aspect ratio for conversion and storage from 16:9 to 4:3, so that the 16:9 image changed to 2:3 pixel aspect ratio and then stored in 4:3 will show up on a 16:9 screen properly. Not sure if that can be used somehow going the other way, but I think that’s what I was trying to determine when I came across the thread.

marqs
As show in the previous picture, DC outputs only 640×480 subsection (which is designed to fill whole 4:3 screen) within that area so it won’t result to correct aspect with modern displays by default.

Ok let me know if this is correct. Sounds like those black bars (that mark where to stop stretching the image on a 640×480 3:4 set) are put there by the DC, but do not affect the pixel aspect ratio coming out of the DC by being there. 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? The chart is helpful, but I found myself wondering about pixel aspect ratio, what does the DC use initially, and does that change internally before it leaves the system via VGA-out, and what is it when it leaves the system? It seemed like if it is changing before it leaves and then the TV is affecting it again, that it would have been a lot tougher to resolve the issues.

marqs

However, recent OSSC fws have advanced timing tweaking option which can reduce the width of signal marked as active from 720 to 640, so monitors and compatible TVs can display only that area when scaling to 4:3 or 16:9 (widescreen games), resulting to exactly correct aspect ratio.

Sounds good, wouldn’t mind some more discussion about my above questions anyway.

With my possible setup below and reading about the OSSC, I see to set 480p line x2 to off for basic 480p passthrough, does using the DTV-480p setting or using the dvi-d-to-hdmi cable somehow cause the output to change to 480i?
( DC <> VGA cable <> OSSC <> dvid-to-hdmi cable <<still 480p here?>> TV )

I pretty much play three games, none burned, on my NTSC system. NTSC Shenmue, NTSC F355 Challenge, and UK-PAL Shenmue2 using a reindeer boot disk that I made to get it started. I know reindeer disk won’t display through VGA.

Has anyone tested these three games to see if the 16:9 aspect ratio setting works on all of them? I know that these should all boot into VGA, but do I have to worry about PAL format with Shenmue 2 conflicting with the the DV standard that I need to set for widescreen? The game appears to run OK on my TV through S-Video, so I am assuming that the game runs in “PAL-60” then.

[RoundCircleS]

Didn’t mean to imply that. I know that 4:3 does not properly scale to 16:9 widescreen. But it seems like maybe that 480p DV standard somehow allows a 4:3 image to be scaled to 16:9 properly, and somehow it can utilize 3:2 aspect ratio when working with 4:3 or 16:9. I think that the DV standard would record in 3:2. I’m not sure how everything works together, but when you guys started talking about using that DV standard and getting better results with the Dreamcast 480p aspect ratio on the display, that sounded like it could be the key, although I really don’t know why. I know pixel shape has something to do with it. I was also concerned about what is actually coming out of the Dreamcast so if this is a solution, it is implemented to get the best results.

[RoundCircleS]

Hi, it says in my TVs manual that my TV HDMI/DVI input recognizes VESA mode in 640×480 with Horizontal Frequency 31.469 kHz, Vertical Frequency 59.940, Pixel Clock 25.175 and Sync Polarity -/- .

Does that so far look compatible with Dreamcast <VGA cable> OSSC 480p DV mode <DVItoHDMI> TV ?

Sorry guys, I am not a whiz when it comes to this stuff but I am trying to understand what is going on. I’m reading through this thread again and maybe the answer is already there, but I’m still trying to figure out where the 720×480 to 640×480 change happens. I was thinking the NTSC TV could be doing it automatically, but then it sounds like the DC might stick the black-bars on both sides of the original image like I thought, but then change that whole image to 640 x 480 by changing the PAR, and that’s how the 3:4 display ends up with a squashed image, nor will it upscale to 16:9 properly. Plus I started to realize that 3:2 is an odd ratio to output video in anyway unless you are recording film to process, but I also know that that ratio pops up somehow during 3:4/16:9 anamorphic wide-screen processing, so maybe that is part of why it does it at all.

I was figuring that my S-Video image in 16:9 is about 10% too wide based on comparing height and width of some circles on the screen, which sounds like PAR pixel aspect ratio difference might come into play as part of the problem there somehow. Then I was also thinking if the DC is narrowing the image by switching it to 640×480 with the intent of being stretched later, you would have to turn that back into the original 3:2 image and then turn that into anamorphic 3:2 (I guess as dictated by the 480pDV standard) in order to get proper 4:3, and consequently tv-up-scaled 16:9. Is that right or am I missing some stuff? Also was wondering more about those black bars, how DC decides to hang them, is it hardware or software? Personally I don’t give a hoot if they stay, as long as I have proper aspect ratio, but I think that there’re graphics under there. Just trying to figure out when things happen in this chain and why. If the OSSC can optimally utilize whatever is going on in the Dreamcast to give us proper aspect ratios in 480p 640×480, that would be awesome.

[RoundCircleS]

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.

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