VGA to HDMI compatibility issues.

[Rock Man]

Hi,

I had bought this VGA to HDMI converter: http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... K:MEWAX:IT

I own this type of television: http://www.gethdtvreviews.com/wp-conten ... -hdtv3.jpg

HD display freatures 480i/480p/720p/1080p, 1x VGA, 2x HDMI, 2x Component, 1x S-Video, 1x Composite.

Now when I got it in and tried it out... the thing kept giving me "Signal Not Supported" or something to that effect. I checked the book and it said it's output video is HDMI 1.2a. I'm not sure if this info would help you guys determine a solution. I'm not really tech-savvy when it comes to this stuff. All I wanted was something to make my Dreamcast games look better.

The converter was recommended to me by this forum and I'm still appreciative for the help. I blame myself for this major failure because I didn't expect my TV to reject the device and wasn't tech-savvy enough to know that it wouldn't work. I'd like to fix this in anyway I can seeing as how I spent a lot of money on this thing. If there's anything I can do, buy a transcoder, compatible HDMI cable, adjust HDTV settings, please enlighten me?

[Fudoh]

Is Dreamcast the only source you tried ? Can you try the converter with the same DC VGA box on a different display, just to make everything's ok there ? The DC's VGA signal is usually very compatible when it comes the standard timings. The converter does nothing but a simple A/D conversion, so I have a hard time seeing which component is to blame.

[Rock Man]

Is Dreamcast the only source you tried ? Can you try the converter with the same DC VGA box on a different display, just to make everything's ok there ? The DC's VGA signal is usually very compatible when it comes the standard timings. The converter does nothing but a simple A/D conversion, so I have a hard time seeing which component is to blame.

WTH!? Tried it out on my Chinese DVD Player and it works fine. What if it's not my TV after all? Is the Dreamcast to blame? I'm REALLY having a difficult time wrapping my head around this. >_<* Gonna try the DC again.

BTW noticed it didn't come with a remote, is there away to adjust it to display in other resolutions Manually like Coosis HD series? I read the book but perhaps I might have missed something, I'll reference it in the meantime while waiting for a response, also gonna re-hook up the Dreamcast. This is so bizarre.

EDIT: Just tried the DC and once again no dice. You think it might be the adapter I'm using? I have a DC VGA BOX which allows me to switch between S-Video and VGA. What do you make of it?

[Fudoh]

The only difference between the DVD Player you tried and the DC is that while both signals are technically 480p, the DC outputs 640x480p while the DVD Player outputs 720x480p. The former is a PC VESA timing, the later one a TV timing (ED). In theory your display could be imcompatible with one of the two signals. Not that I have encountered anything like this before, but it's a possibility you might want to explore. Easiest possiblity to check both (720 and 640x480) is to simply connect a PC and set the output to those resolutions (you have to disable the graphics card's internal scaling though).

Another possibility are the DC's RGB levels while in VGA mode. They can be quite high and possibily so high that a converter like the one you've got and get thrown off. A way to fix this is to damp the signal levels using some resistors.

There's nothing on the box to adjust, it's just a A/D converter. Whatever comes in, gets output.

[Rock Man]

So, basically what you're telling me is my TV isn't compatible with such display timings. But I was able to play DC just fine using the TV's regular VGA input socket. Are you sure it was the PC VESA timing?

I'll do what you asked with the PC check, but it may take some time.

The purpose for this converter was to get a better quality signal out of my DC games, while they look good in VGA I thought I might be able to tap into something better. Also I partially agree on the RGB levels being too high, I believe it's part of the reason why my Coosis rejected the DC SCART cables. Even so I wouldn't know how to adjust the resistors.

[StarCreator]

I have to say, I'm a little confused why you pursued this if you already had working VGA input on your TV. Why did you think converting it to digital would give you better output? The converter just converts the signal as-is; it doesn't do anything to improve it, and in fact you probably lose a little bit in the transition. If anything, a lot of inexpensive HDTVs do stupid things to their HDMI inputs to make them "look" better to the average TV viewer (the worst of all, resizing the image to get rid of overscan, sacrificing pixel to pixel mapping in the process), that they don't do to their VGA inputs.

As for the problem at hand, it wouldn't surprise me in the slightest if your TV's HDMI implementation only handles the typical TV-spec 480p/720p/etc resolutions, because that's what most consumers would be plugging in.

[Endymion]

What he said.

If you are hellbent on using this device, the thing to do at this point is to try to use it with another digital input, not on your screen but on another. The results of that could be telling. Try it with a friend's, or a family member's screen if you know anyone who has one. If you have a cable with HDMI on one end and DVI on another, try that if you have a screen with input for it, even a computer screen.

A lot of VGA inputs are much more forgiving for odd resolutions because it is much more easily adaptable for the hardware. It just changes where you start and stop. If I remember a lot of Dreamcast games via VGA back in the day, and even the Dreamcast dashboard for that matter, I don't seem to recall the image filling the screen at all times during boot or during play. So it's possible that what you are seeing could be the result of your screen's digital input finding a resolution that does not perfectly match the ones that it has been coded to support. It is typical in circumstances like this for the thing to just not work(tm).

An alternative that might work just might have the same exact problem if the issue described above is at fault: you could use a VGA to Y-Pb-Pr device, then convert that over to HDMI, but again anybody's guess how the digital input will handle it if it does not match up with what it expects to see, certainly not anything to spend money on to try out if you ask me.

[Fudoh]

while they look good in VGA I thought I might be able to tap into something better

on many TVs the HDMI ports also include more processing, adding possibly more lag and hurting graphics signals in general. On many TV sets the HDMI ports' quality equal more the Component inputs than the VGA input. For reasons of readability of small text, the VGA port involves the least processing, giving the sharpest picture on graphics signals.

[Rock Man]

Subject: VGA to HDMI compatibility issues.

I have to say, I'm a little confused why you pursued this if you already had working VGA input on your TV. Why did you think converting it to digital would give you better output? The converter just converts the signal as-is; it doesn't do anything to improve it, and in fact you probably lose a little bit in the transition. If anything, a lot of inexpensive HDTVs do stupid things to their HDMI inputs to make them "look" better to the average TV viewer (the worst of all, resizing the image to get rid of overscan, sacrificing pixel to pixel mapping in the process), that they don't do to their VGA inputs.

As for the problem at hand, it wouldn't surprise me in the slightest if your TV's HDMI implementation only handles the typical TV-spec 480p/720p/etc resolutions, because that's what most consumers would be plugging in.

I thought it would grant me a better picture because the last device I had was a upscaler, after viewing the specs on the VGA converter I noticed it supports 720p/1080p. So naturally, do to my lack of tech knowledge and bad guess work; I was lead to believe it would give me a the ability to manually upscale/downscale the quality as I please, much like my Coosis converter. You can imagine my surprise when I got it in and it failed.

I've learned my lesson, no more buying things to "supposedly" boost the quality when the projection is already decent enough looking! Just too bad I spent so much just to get humbled, it was a hard lesson. I guess that's what happens when you get spoiled after viewing the crispness of a projection, you get greedy and desire MORE. This is exactly what happened in my case.

while they look good in VGA I thought I might be able to tap into something better

on many TVs the HDMI ports also include more processing, adding possibly more lag and hurting graphics signals in general. On many TV sets the HDMI ports' quality equal more the Component inputs than the VGA input. For reasons of readability of small text, the VGA port involves the least processing, giving the sharpest picture on graphics signals.

Man, you're really knowledgeable when it comes to this stuff Fudoh, my compliments. I had no idea VGA is capable of sharper picture. o_O But then again this DOES solely depend on the machines you're using. Something like a Dreamcast MIGHT look better in VGA than it would in HDMI if converted. I see that now. Whereas a 360 would stand out in HDMI instead of VGA since it was built for Component (Ypbpr) and not VGA's RGBHV type.

Initially I did this with a goal in mind. To achieve the highest possible image with the DC on a modern TV (HDTV in this era). Perhaps deep inside I know DC is lagging behind the higher tier consoles so I did what I could to make it formidable but to no avail. Plus I recalled that conversation we had, when I was on my RGB SCART campaign and you said upgrading to VGA instead would make for superior results. At the time I already invested too much in SCART gear, converters/switchers to start a new quest for SCART/RGB cable to VGA conversion methods so I decided against it. I did however consider the possibilities of VGA being upscaled to HDMI would look further rich in detail. The idea intrigued me, that's when I remembered the converter you recommended.

I was further motivated after seeing some earlier Capcom DC fighters. I compared many games and while I noticed most of them looked STUNNING (DOA2, GGX, KOF2k2, Ikaruga, etc.) some of Capcom's were a little bit disappointing, (SF3, SFA3, Power Stone 1, MvC1, MvC2, etc.) every game Capcom related with the exception of CvS2: Miliionaire Fighting 2001 looked heavily jagged up, too rigid. I concluded that an HDMI 1080p conversion would fix this. I guess you can say another possible reason was the Capcom titles. I don't get why there is such a gap in the other games I tried and the Capcom stuff. It's not to say it looked bad, I found the image average at best but I was almost certain it could be better. I'm also aware those games really stand out on a smaller tube monitor, I wasn't really interested in getting one. My only possible use for it would be Dreamcast and I'd want to use it for many other purposes.

All things considered, since you said VGA upscaled on most TV's isn't better than the raw VGA signal I'll stick with connecting the VGA lead directly to the socket. I'll just have to learn to tolerate the mediocre quality of those earlier Capcom games. Atleast it isn't as bad as when I first hooked my Genesis and SNES into the HDTV using AV & S-Video cables. That's what got me into this **** seeking out a higher quality for every hardware I own. I'm still on a quest to achieve the ultimate entertainment set-up, but the road to becoming a high quality HDTV & devices enthusiast is a harsh and costly one!

Just had a thought, a while ago I recall Wikipedia said the Dreamcast can output in DVI through a VGA converter. Would this be a form of upscaling? (BTW my current PC monitor does use VGA, that's what my tower is hooked up to. But if DVI can grant a better picture on DC titles...) I was informed your average electronics giant sells these gizmos. I was thinking about getting one but now that I've seen the implications of my actions on that last adventure I want to pursue this very carefully.

[Fudoh]

No, the DC can't output DVI through the VGA box. DVI and HDMI are basically the same btw. VGA itself is a very nice and very clean signal. On a good display (which treats VGA and DVI the same) there's no reason for visible differences.

The reason why some of Capcom's titles look disappointing is the internal scaling Capcom has applied. Titles like Street Fighter 3 have been 15khz (384×224). As you can see this is a resolution which can only be hardly scaled to 640x480. Capcom has choosen mediocre algorithms which introdue the jaggies (same problem as with Ketsui on the 360 btw). A few of the titles you're refering to might actually look better when output in 240p instead. SF3 for example, while still a bit jaggy, looks excellent via 240p RGBs into an XRGB-3.

In general the scaling of today TVs and monitors is fine. The reason why RGB/YUV to VGA "upscalers" (well, the word upscalers is basically wrong) are recommended is that bad deinterlacing and postprocessing on the TVs analogue SD inputs. Once you've taken this step (by using a XRGB or Coosis box etc..), it's usually as good as it gets. There are ways to get better scaling as well, but that involves complicated hardware (e.g. the Optoma HD3000 scaler) or is only worth the effort if your TV does upscale real bad (e.g. some Samsung TVs really suck at 480/720p to 1080p).

[Rock Man]

No, the DC can't output DVI through the VGA box. DVI and HDMI are basically the same btw. VGA itself is a very nice and very clean signal. On a good display (which treats VGA and DVI the same) there's no reason for visible differences.

The reason why some of Capcom's titles look disappointing is the internal scaling Capcom has applied. Titles like Street Fighter 3 have been 15khz (384×224). As you can see this is a resolution which can only be hardly scaled to 640x480. Capcom has choosen mediocre algorithms which introdue the jaggies (same problem as with Ketsui on the 360 btw). A few of the titles you're refering to might actually look better when output in 240p instead. SF3 for example, while still a bit jaggy, looks excellent via 240p RGBs into an XRGB-3.

In general the scaling of today TVs and monitors is fine. The reason why RGB/YUV to VGA "upscalers" (well, the word upscalers is basically wrong) are recommended is that bad deinterlacing and postprocessing on the TVs analogue SD inputs. Once you've taken this step (by using a XRGB or Coosis box etc..), it's usually as good as it gets. There are ways to get better scaling as well, but that involves complicated hardware (e.g. the Optoma HD3000 scaler) or is only worth the effort if your TV does upscale real bad (e.g. some Samsung TVs really suck at 480/720p to 1080p).

Alright Fudoh, I'll hold off on the VGA to DVI converter even though wikipedia states it can be done. I'm gonna play it safe this time. Now I know what's the problem, the internal scaling which leads to low resolution. YARGH! Capcom just had to complicate things, why couldn't they just adjust it to 640x480 like the other companies did? At the very least this time around SNK's games look superior to Capcom's resolution wise... for the DC only. Something I can use to smear in Capcom fanboys collective faces should they knock SNK. XD Lol, let me stop fooling around though.

Now I've seen this XRGB stuff mentioned before, from what little I know it'll take RGB SCART, Component, Composite, and S-Video and enhance the signal to VGA mode. In addition to this it offers some kind of USB feature. Hmmm, I wonder.... Given the circumstances the Capcom games display don't impress me anymore on the DC. I want to try and save them. The Coosis Universal HD series latest box won't take Dreamcast SCART ( Believe me I've tried. ) But the earlier 720p one does which is more difficult to find on Ebay. For some reason I prefer to go a different route this time.

What's your opinion on the XRGB-3 and the Dreamcast games that don't output in VGA mode normally? (Like for example Last Blade 2, Jojo's Bizarre Adventure, KOF '99, etc.) If I use it on Dreamcast's RGB SCART lead for boosting/converting the signal to VGA will it allow unsupported games to display in VGA output? Also, can it really enhance the image quality of Capcom games (Third Strike/Alpha 3, etc.) in VGA from RGB SCART? If this is the case I WILL invest in one.

Assuming this works I may need a restructure my set-up. I'm using a DC Component VGA Box now with the standard S-Video TV connection. From what I've learned it's possible to modify the box to take RGB SCART, I've seen screenshots of it on Google. How common are these modifications to the box? Think I can get them from a place like Ebay or Amazon dot com? I'm not familiar with soldering and things like that, I can't mod it myself.

My goal is to make my connections completely convieniant so I'll never have to swap again. All other units are pretty much taken care of. The last ones to go are the Dreamcast, Saturn, and PS2 (already worked out a stratedgy for PS2.) I know it sounds convoluted but I REALLY want my Dreamcast to be hooked up to all 3 outputs at once. S-Video, RGB SCART, VGA.

Can it be done?

[Fudoh]

Alright Fudoh, I'll hold off on the VGA to DVI converter even though wikipedia states it can be done.

there's just no digital signal anywhere around.... Do you have a link to where it states that it's possible ?

What's your opinion on the XRGB-3 and the Dreamcast games that don't output in VGA mode normally? (Like for example Last Blade 2, Jojo's Bizarre Adventure, KOF '99, etc.)

some great, others not. Games running in real 240p, run through the XRGB-3 look ace. This includes Street Fighter III and games like Bangai-Oh. Those games look like on a CRT, with visible scanlines. Others running in 480i only, will look less good. To optimize those you'd need a more dedicated setup, e.g. Coosis -> Emotia -> XRGB. (Read my Scanlines page for details. It's aimed at CRT users, but the idea is the same).

I REALLY want my Dreamcast to be hooked up to all 3 outputs at once. S-Video, RGB SCART, VGA

why ? Are there any games which don't work with RGB Scart *OR* VGA ? None that I can think of. There's also a nice mod for the standard RGB Scart cable, so some of the non-RGB Games can be output using Scart (includes Skies of Arcadia)...

[Rock Man]

Alright Fudoh, I'll hold off on the VGA to DVI converter even though wikipedia states it can be done.

there's just no digital signal anywhere around.... Do you have a link to where it states that it's possible ?

DVI compatibility
The VGA box can be connected to a HDTV or PC monitor's DVI (Digital Visual Interface) port with a simple mechanical adapter. The DVI port has to be DVI-A or DVI-I compatible. DVI-D will not work. Expensive digitizers are required to work with digital-only displays.

http://en.wikipedia.org/wiki/Dreamcast_VGA

I maybe using the wrong choice of words here... I don't care if I get a digital signal or not. If I can improve the Dreamcast VGA quality by hooking it up in DVI-A or DVI-I which I do believe my PC Monitor supports, this would be beneficial for me.

some great, others not. Games running in real 240p, run through the XRGB-3 look ace. This includes Street Fighter III and games like Bangai-Oh. Those games look like on a CRT, with visible scanlines. Others running in 480i only, will look less good. To optimize those you'd need a more dedicated setup, e.g. Coosis -> Emotia -> XRGB. (Read my Scanlines page for details. It's aimed at CRT users, but the idea is the same).

Shoot! Man, I underestimated the price point for the XRGB-3. That thing is expensive! I would have went for it had it said $40 or even $130 but a whole $330.00 is a bank breaker. Looks like my only other alternative is to grab one of those Coosis 720p converters since the 1080 one rejects Dreamcast. >_<*

why ? Are there any games which don't work with RGB Scart *OR* VGA ? None that I can think of. There's also a nice mod for the standard RGB Scart cable, so some of the non-RGB Games can be output using Scart (includes Skies of Arcadia)...

You know what? I really can't think of a reason why I should want to play it in S-Video after I said that. Other than to compare the crappy luminace and color picture you'd get on an HDTV to the higher quality true RGB sync from SCART or RGBHV near limitless colors from VGA. Despite S-Video looking pretty damn good on standard televisions it's rubbish on most HDTV's. Guess I don't need S-Video but never the less, if I find one of those boxes wouldn't it come with S-Video regardless? I don't see any reason why the modder would replace the S-Video with RGB SCART unless they needed the Composite part (Yellow/White/Red) in order to tap into the RGB sync. BAH! This is irrelevant anyway. If I could get one of those modified RGB SCART/VGA Component DC boxes I'll be truly satisfied. Think I'll start searching now.

[Fudoh]

DVI-I and DVI-A just allow the connection of VGA signals. It makes absolutely no difference if you connect a VGA source to a pure VGA Port, a DVI-A port or a DVI-I port. The signal's the same. Connecting a VGA signal to a VGA-compatible DVI port, doesn't make it a DVI signal.

Looks like my only other alternative is to grab one of those Coosis 720p converters since the 1080 one rejects Dreamcast. >_<

I think it's worth looking into this incompatibility issues. There's no logical reason why your newer Coosis converter should not accept a DC's RGB signal. Probably just an issue of wrong signal voltage levels or bad/wrong blanking signal.

[Rock Man]

I dunno, maybe.

Earlier you asked me of a game that doesn't support RGB or VGA. Well I found one, it's Vampire Chronicles.

Thanks for the info on DVI I'll hold off on that. About the Coosis I believe the reasons why it doesn't take the DC's SCART RGB is because it's probable lack of 640x480 resolution. Essentially about the same problem your describing having to do with the display projection, when I plug it up I get sound but a flickering image, sometimes no picture at all, just a black screen. Whatever the cause is I HOPE Coosis fixes it. I'm trying to play Jojo's Bizarre Adventure and Last Blade 2 in 1080p on my Dreamcast system! I know the 1080p converter would smooth the Dreamcast out. It turned my Saturn into a beast!

[Fudoh]

Well I found one, it's Vampire Chronicles

interesting! makes me wonder what morons playtested this before pressing it...
Googling a bit I found that there are both RGB and VGA patches available for it, so in this rare case (and if you own the original anyway), I wouldn't hesitate to download a ripped and patched version.

[Rock Man]

Sounds like a plan. I'll do that.

I have no idea how to go about looking for the compatibility issues between the new Coosis converter and the DC. Technology wise I probably won't be able to just crack open the thing and service it myself. I contacted a Coosis Employee about it though, they said they're on the case.