Video connections sure are confusing. I have a degree in electrical engineering from an Ivy League institution, and I'm befuddled by it all. I feel sorry for you mere mortals out there.
I'm building a media PC from scratch, and I'm trying to get a good video display. Mind you, at this point, I'm not trying to play video media. I'm just trying to wring the fuzzies out of the display when I run the music player or web browser.
The computer has VGA, S-Video, and DVI video outputs. The television has composite, S-Video, component video, and HDMI inputs. You'd think that with all those choices, there would be some way to insert tab A into slot B and make it all work.
The first and obvious choice is S-Video–both units have that. In fact, as I reported in that prior article, S-Video works. Unfortunately, it doesn't work so good. You may be surprised to learn that S-Video has the same crappy resolution as the bottom-of-the-line composite video connnector. Both do 480 interlaced scan lines, The difference is that S-Video separates out the signals so it's a crisper 480i. That means with S-Video, I'm trying to display 800x600 on 480 interlaced scan lines–no wonder it looks like crap.
I wanted to do better, but S-Video is the only connection the two had in common. The "high def quality" component video TV inputs would be ideal, but the computer doesn't have matching outputs.
After some web searches I found an adapter jig that would connect up to the DVI connector of an ATI video card and produce component video. My on-board video is ATI, so I thought this would be a shoo-in. All I needed was this one cheap adapter and it was component video all the way.
Well, not quite so fast Poindexter. When I got the adapter it wouldn't fit. That's when I learned that there isn't just one kind of DVI connector. There is DVI with digital video signals (DVI-D), analog video signals (DVI-A), and a combination of the two (DVI-I). Moreover, there are single-link and double-link DVI-D connectors (double has more pins). This adapter jig was made for a DVI-I connector, and it used the analog outputs to produce component video. My computer has a DVI-D connector with no place for the analog pins to fit into. That's why the connector wouldn't fit.
So, it was back to the drawing board. I found devices that convert DVI-D to component video, but at over a hundred bucks that didn't make sense. I thought about getting a DVI-D to HDMI cable, but they aren't cheap. Moreover, the A/V receiver I have my eye on has component video inputs but not HDMI. I really want to get component video.
I concluded there is no reasonable way to go from digital DVI to analog component video. But what if I could do analog all the way? That got me thinking: computer VGA is an analog video signal. Is there some way I could get component video from a VGA output? Unfortunately, not easily. The signals aren't compatible. VGA uses RGB (red, green, blue level) signals, while component video is YPbPr. It appears that at least some ATI adapters can be kludged to produce component video signals on the VGA connector. Even if my hardware can support that, I'm not sure if the Linux fglrx video driver can. I haven't ruled it out, but it's a longshot at best.
I'm not sure if I'm getting any closer to a solution, but I'm getting a heck of an education on video interconnections.