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S-video (TV) vs CRT VGA display: examples
MonMotha:
--- Quote from: Gray_Area on November 03, 2011, 10:27:23 pm ---the brightness is up because otherwise the whole thing looks too dim
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If the display is overall "dim", the control you want to adjust is *contrast* not brightness. Contrast actually controls "how bright things get", which you might call "intensity". Brightness actually adjusts the "black level" i.e. the signal level at which the signal is considered "totally black". Turning this up won't actually make the image brighter, it'll just make black look gray. Turning up contrast will make the picture "brighter", but how high you can turn it up is limited by several things, especially the condition of the tube. If the tube is old and worn out, then it will start to "bloom" and saturate if you try to make it too bright.
The reason for the oddball terminology is historic. Just remember: contrast is "how bright it gets", and brightness is "how dark it gets". BOTH settings are important.
To be clear, I think that your s-video picture looks AWFUL; I'm just saying it doesn't have to be that way. Are you using the s-video output on a PC for this? If so, well, your PC's s-video output probably sucks (which is normal). Your TV, while using the "same tube technology" is probably not built to nearly the same quality that your monitor is: it's probably got cheaper signal processing, and the tube is probably of poorer quality (and older / more worn). The fact that you claim you need to turn up the brightness because the monitor is "dim" suggests at least the latter. An interesting comparison would be to find a TV that features both inputs and compare them.
An RGB connection will always look at least a little better than s-video, but outside Europe, it's hard to find a CRT television with RGB inputs that will accept standard res (arcade) video, while s-video is common. That's the motivation for using it. It can be quite serviceable, but it's only really compelling due to it's availability, not because it's particularly good.
Also, your S-video picture DOES look more like a DL arcade (I have a friend with one) than your RGB picture does. I won't say it looks BETTER (it definitely doesn't), but it is actually more authentic in this case due to the limitations of the original arcade setup. Your Daphne video is probably ripped from the Blu-Ray or at least a VERY good LD player on a good condition disc, which the arcade didn't have.
leapinlew:
--- Quote from: Gray_Area on November 03, 2011, 10:27:23 pm ---**What I see in the S-video images above is exactly what I've seen in my own efforts. So, I call hogwash on the lighting and camera/flash comment. I'd call hogwash on it anyways, because I know what I see.
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I have built several video games using TV's, Arcade monitors, LCD's and computer monitors. Yes, there is a difference in both the tube and the connectivity, but those S-video pictures you posted are just terrible and don't represent anything I've seen . All my S-video tv connects look great, minus the clipping issues. They don't look anything like those crappy pictures you posted.
I call hogwash on your hogwash.
RandyT:
--- Quote from: MonMotha on November 03, 2011, 10:12:42 pm ---Many cheap TV sets don't actually have an S-Video input! Instead, they just internally re-combine the s-video into composite much like those adapter dongles do. The result is actually WORSE than composite due to some technical subtleties. On these televisions, there's no reason to use S-Video as it won't look any better than composite, and the connector sucks :)
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I'm not one to purchase overly cheap TV's, so I've never come across one like this. That being said, they probably do exist, but if this were the case, it should be very simple to discern if the end result is worse than composite. But, I am unconvinced that the result would necessarily be so. If the TV had superior circuitry to combine the luma and chroma signals than the source device using those same signals to create it's composite output, it would stand to reason that the result would still be better.
--- Quote ---Most PC s-video outputs are total garbage. They smash and crush the signal so that it "fits".
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I'm a bit stymied by this statement. The PC handles the "smashing and crushing" in the digital realm, not the analog. It will do a digital scaling of the image (i.e. de-interlacing, some loss of detail, optional addition of anti-aliasing and whatnot), but the "signals" sent to the TV can still be quite clean.
--- Quote ---If you "disable overscan", the result is even worse since that works by simply scaling down the picture and putting black bars around it. They're simply awful.
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Well, awful, possibly, but not nearly as awful as having an important part of the playfield in a game hidden from view. Lesser of two evils, etc....
--- Quote ---Now, component YPbPr video is functionally identical to RGB. The conversion can actually be performed losslessly, though most digital converters will downsample the color 2:1 horizontally (4:2:2 subsampling) which is almost impossible to see on photorealistic images but fairly evident on sharp computer/game graphics. Aside from that, any remaining appearance differences between these two connection formats are simply due to your TV being set incorrectly (or sucking).
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Component is definitely good (better than S-Video), but to say that it "functionally identical" is a little misleading. The quality of the result is still heavily based on the quality of the circuitry which disassembles the R, G, B and Sync components from the combined signals output by the device. True RGBS is not reliant upon this type of processing circuitry, so the result is still going to be considerably better in almost all practical cases. RGBS from component still needs to be derived, while RGBS simply is.
--- Quote from: Gray_Area on November 03, 2011, 10:27:23 pm ---First off, besides being RGB, the only difference between my monitor and the S-video TV is that mine is at a higher resolution. A 27" PC monitor is the same tube technology.
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No, it's not. This is akin to stating that the only difference between a '75 Chevette and '12 Porsche is that the Porsche goes faster. There are many other things in the design of the PC monitor which allow it to be good at what it was designed to do, that just aren't required and are therefore omitted from the S-Video TV. To do a true comparison of the two inputs types, you would need to use a true Multi-Sync monitor with video capability, with a quality S-Video signal source. There are far too many variables in displays across different manufacturers and price ranges to come to a definitive conclusion in any other way. The folks who have been doing this since the early days understood that not all televisions and graphics cards are created equal, and put a good deal of effort into finding the ones which would do well in this application.
RandyT
MonMotha:
--- Quote from: RandyT on November 04, 2011, 01:13:53 am ---
--- Quote from: MonMotha on November 03, 2011, 10:12:42 pm ---Many cheap TV sets don't actually have an S-Video input! Instead, they just internally re-combine the s-video into composite much like those adapter dongles do. The result is actually WORSE than composite due to some technical subtleties. On these televisions, there's no reason to use S-Video as it won't look any better than composite, and the connector sucks :)
--- End quote ---
I'm not one to purchase overly cheap TV's, so I've never come across one like this. That being said, they probably do exist, but if this were the case, it should be very simple to discern if the end result is worse than composite. But, I am unconvinced that the result would necessarily be so. If the TV had superior circuitry to combine the luma and chroma signals than the source device using those same signals to create it's composite output, it would stand to reason that the result would still be better.
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I've not personally witnessed one, but I've heard from a few TV techs that this is the case on some really cheap sets (I think qrz mentioned it once on here, for example), and some really cheap TVs seem so poorly made that I believe them. Apparently the method of combining the two s-video components is just a simple capacitor which acts as a high-pass filter on the chroma - same as those passive dongles. There are certainly better ways to do it, but the objective is to be cheap in this case, after all. They just want a bullet point ("Supports S-Video!"); they don't care if it works well.
The result is comparable to a badly/naively generated composite signal (no trap or chroma comb); it's not much worse than a "properly" generated composite signal, but most PC cards seem to offer a "composite" setting that MAY do a little better than such a simplistic conversion. It certainly won't be comparable to a real s-video signal.
--- Quote from: RandyT on November 04, 2011, 01:13:53 am ---
--- Quote ---Most PC s-video outputs are total garbage. They smash and crush the signal so that it "fits".
--- End quote ---
I'm a bit stymied by this statement. The PC handles the "smashing and crushing" in the digital realm, not the analog. It will do a digital scaling of the image (i.e. de-interlacing, some loss of detail, optional addition of anti-aliasing and whatnot), but the "signals" sent to the TV can still be quite clean.
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The issue isn't necessarily that the scaler is particularly bad (they're usually "OK", but I wouldn't call the ones I've seen "good"), but that it will usually scale EVERYTHING you feed it, even if it doesn't really have to. Basically, the s-video outputs don't usually support "native" resolution passthrough. They will take all your carefully set video timings and mash them to some fixed mode, even if what you're generating is actually TV compatible to start with. This doesn't necessarily "destroy" the image completely, but it will certainly soften it quite a bit, as the scalers are usually just a bilinear type or something similar. SOME s-video outputs (some old ATi cards, I'm told) will pass through compatible resolutions with no scaling (just a colorspace conversion and chroma modulation - ala the outboard "RGB to S-Video converter" boards). This can look pretty darned good, but it seems the exception, not the norm. The "component" (YPbPr) outputs on most cards seem to pass everything through without scaling, relying on the system to configure a compatible resolution, which is much nicer.
I also think some bad PC cards may just output composite whether you ask for s-video or composite. This one I have no evidence whatsoever on, but given how bad some people's results are and the cost pressures on commodity PC hardware, I'd believe it. This would be easily fixed by getting a better video card, at least.
--- Quote from: RandyT on November 04, 2011, 01:13:53 am ---
--- Quote ---If you "disable overscan", the result is even worse since that works by simply scaling down the picture and putting black bars around it. They're simply awful.
--- End quote ---
Well, awful, possibly, but not nearly as awful as having an important part of the playfield in a game hidden from view. Lesser of two evils, etc....
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That's true. The result is basically the same as the initial scaling described above with the added detriment that there's a loss of (at least vertical) resolution. Some systems also seem to perform the two steps separately, resulting in double-scaling artifacts like moire patterns and extra soft edges, but I can't confirm that this is the case. In any case, I would certainly agree that it's certainly better to display everything needed rather than cut it off.
The ideal solution would be to adjust the television's geometry in service mode to effectively remove the overscan, but this is difficult or impossible in some cases.
--- Quote from: RandyT on November 04, 2011, 01:13:53 am ---
--- Quote ---Now, component YPbPr video is functionally identical to RGB. The conversion can actually be performed losslessly, though most digital converters will downsample the color 2:1 horizontally (4:2:2 subsampling) which is almost impossible to see on photorealistic images but fairly evident on sharp computer/game graphics. Aside from that, any remaining appearance differences between these two connection formats are simply due to your TV being set incorrectly (or sucking).
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Component is definitely good (better than S-Video), but to say that it "functionally identical" is a little misleading. The quality of the result is still heavily based on the quality of the circuitry which disassembles the R, G, B and Sync components from the combined signals output by the device. True RGBS is not reliant upon this type of processing circuitry, so the result is still going to be considerably better in almost all practical cases. RGBS from component still needs to be derived, while RGBS simply is.
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My bad. My comment was limited to the signal itself, assuming a "perfect" monitor. Basically, it's possible to create a YPbPr signal that's equivalent to the RGB signal from a mathematical point of view and would display identically on a perfect monitor. Obviously most TVs are far from perfect - they're designed to be cheap, not good - so you're right, there is a real world loss in quality as a result. Most RGB to YPbPr conversions also involve a loss of color resolution (2:1 horizontally as described) since that just seems to be how everybody does it, so from a practical point of view, RGB would still be better. You can get around the latter by doubling the horizontal pixel count in software and making sure the converter handles this double res, but you're still limited by the quality of the TV in the conversion back to RGB. Most pictures I've seen of people using YPbPr component look decent except for a severe need to tweak the settings, which can be painstaking for an experienced monitor tech, let alone someone who doesn't deal with it frequently.
I've done most of my TV testing using a friend's 2000-era Sony WEGA and custom-built "no compromises" (and therefore rather expensive) conversion hardware. This is a rather high end model TV, so that in combination with the high end conversion hardware may explain my better than normal results. I've had much less positive results when using PC s-video outputs, as one might gather from my comments.
TL;DR: If you've got an RGB capable monitor/TV, use it. Otherwise, YMMV when using YPbPr component or S-Video.
Malenko:
--- Quote from: Gray_Area on November 03, 2011, 10:27:23 pm ---@ Malenko: my images are closely the same perspective; yours aren't.
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There are more in the thread, I didn't wanna bombard this thread with pix. The PolePosition cab I jammed a 27" TV in is currently using SVideo and it doesn't look as bad as the pink dragons lair picture above. Maybe I'll download and run Dragon's Lair and take a pic. I'll have to do Dragon's Lair 2 though, cause I have the DVD for that one.
Ive seen composite feeds look better than that.