Hardware Card Resolution

[BigBuddha]

Hi,

I am using a Hauppage PVR 150 MCE, which I believe has a maximum effective resolution of 768x576. At least ths is what MP reports (in the log) when it opens the card up for viewing.

Does anyone know of a MP supported Hardware Capture card that has a greater resolution than that ?

Thanks in advance

BB

[jawbroken]

That is the maximum resolution of analogue video (well, horizontal resolution in analogue is a tricky thing at best, but practically it is the resolution). But there are no more lines in the video stream, so capturing at any larger vertical resolution is not possible, so any higher resolution would be just interpolating between lines. This is useless to do on the card, as the video will be scaled to display on screen and do the same thing anyway.

Sites like http://hometheater.about.com/cs/tele...avideoresa.htm will show you that analogue video has limited vertical and horizontal resolution, so a theoretical card (I don't believe any exist that have a significantly higher resolution that what you specify above) with a greater resolution would not show any better quality video.

[BigBuddha]

Originally Posted by jawbroken

That is the maximum resolution of analogue video (well, horizontal resolution in analogue is a tricky thing at best, but practically it is the resolution). But there are no more lines in the video stream, so capturing at any larger vertical resolution is not possible, so any higher resolution would be just interpolating between lines. This is useless to do on the card, as the video will be scaled to display on screen and do the same thing anyway.

I understand what you are saying, and I am sure that you are right. However, when I run the signal from my Cable STB straight into the HD TV the PQ is way better than when I run the same signal into the Hauppage and on through MP. And it's not just a little bit better PQ it is a whole lot better!

It looks to me as though the Hauppage is reducing the signal down to 768x576? The only other explanation is that the TV is upscaling the signal resolution from 768x576 in which case you should still get the same PQ both ways, because this is what MP currently does with the Hauppage.

There has to be a way to get the same PQ when the signal is run through the HTPC as when the signal is sent straight to the HDTV.

I am using component for both tests and when I view Digital HDTV through MP it looks superb, so I know that all of the setup regards MP and connection to the TV is ok.

[jawbroken]

I read about your PQ issues in the other thread. I am just not aware of any card that captures at a higher resolution because the information is just not there in an analogue signal to capture.

[onkl]

While I believe you without hesitation, I doubt if resolution is the key.

Since the signal is analogue, the cable signal can contain jitter, noise etc, or, so to say, unwanted information.
To deal with that, TV's have some filters on board. MP can do something like that too. Try some searching on terms like DScaler, FDD post processing etc.

[BigBuddha]

Originally Posted by onkl

While I believe you without hesitation, I doubt if resolution is the key.

Since the signal is analogue, the cable signal can contain jitter, noise etc, or, so to say, unwanted information.
To deal with that, TV's have some filters on board. MP can do something like that too. Try some searching on terms like DScaler, FDD post processing etc.

This really is not like looking at a signal that has had some noise or jitter removed, it is like on one hand all of the text and sharp edges (especially) are super well defined and crisp and couldn't look any better; and on the other hand all the same stuff looks blurry, smudged and has MUCH lower definition. You can see the same thing in the general PQ it's just easier to describe with edges and text and things like the STB's OSD etc.

I have used Dscaler to view the card and initially it provided better results than MP when I was only using RC2 standard because of the following from the logfile.

21/01/2006 9:14:34 AM PlaneScene: video WxH : 768x576
21/01/2006 9:14:34 AM PlaneScene: video AR : 768:576
21/01/2006 9:14:34 AM PlaneScene: screen WxH : 628x330

but now that I have applied CVS 21/01/06 I get this:

23/01/2006 8:48:57 PM PlaneScene: video WxH : 768x576
23/01/2006 8:48:57 PM PlaneScene: video AR : 768:576
23/01/2006 8:48:57 PM PlaneScene: screen WxH : 1292x732

notice the difference in the last lines. So now MP is on an equal footing with Dscaler, but neither of them come anywhere close to the PQ when you inject the signal straight into the telly.

If it were only a little bit different I woudln't worry but it is a HUGE difference, I wish I could take a sceen shot of both to show the difference. You would be amazed I am sure!

At one stage I ran the signal into my software capture card a VSTREAM XPERT PCI 100 and apart from some additional noise that it added to the picture the PQ was almost identical to when I run the signal straight into the HDTV, surely that must mean that the Hauppage capture card is letting the team down in some way?? Maybe it isn't about resolution, maybe the Hauppage is compressing the stream too much.

In fact now that I think of it, that is exactly what it looks like, like when a JPEG has been compress too much and starts to lose it's definition. Maybe that can lend a clue as to how it can be fixed it or maybe a card that can process at a higher bitrate than 12000 Kbits/sec with an average of 8000 ???

[wewe]

well I don't know if that is a help for you because you are having a high-end TV and I am running an old tube TV. But I want to share that information:

I do have a STB for digital cable TV (Nokia D-Box in germany). Besides of that I am receiving analog cable TV directly through PVR150. My TV is connected through component.

- in the beginning I did route the STB signal through component to PVR150 and the quality arriving at the TV was awful.

- then I changed to S-Video and now I am having a very good quality.

So my situation is:
- if I go through component from STB to TV it is quite good
- if I go through component to PVR150 and through component to TV -> awful
- S-Video to PVR150, component to TV -> quite good.

My guess: two times through component = bad x bad

thanks+regards
WeWe

[BigBuddha]

Originally Posted by wewe

So my situation is:
- if I go through component from STB to TV it is quite good
- if I go through component to PVR150 and through component to TV -> awful
- S-Video to PVR150, component to TV -> quite good.

Many thanks for the input wewe. I have ordered a SCART to S-VIDEO converter (my cable STB has no S-VIDEO output, but two scarts and two components, what were they thinking ????) which will arrive here tomorrow and I intend to check out any increase in Picture Quality that it might provide.

I am not expecting a miracle because I have already seen good PQ when running component into a Software encoding card and RGB (which is the same as connecting to a computer montior) from the PC to the TV.

After all that has been said and confirmed about the res being a max of 768x576 with no increase in performance gained in higher resolution. I am now thinking the answer might lie in overcompression by the PVR150 MCE, but at the moment I can't think of a way to test this theory out

[jawbroken]

I think both of you probably mean "composite" not "component"? Component video uses 3 cables for video, where composite uses one (usually yellow plug). Component can be RGB or Y Pr Pb, I think Y Pr Pb is more common (or at least around here), but the cables are always red green and blue regardless.

The conversation is getting confusing to follow (eg "running component into a Software encoding card and RGB (which is the same as connecting to a computer montior) from the PC to the TV", probably means composite in and component out? not sure) with this mixup. I don't know of any capture cards that capture component video, but they may exist?

[BigBuddha]

Originally Posted by jawbroken

I think both of you probably mean "composite" not "component"? Component video uses 3 cables for video, where composite uses one (usually yellow plug). Component can be RGB or Y Pr Pb, I think Y Pr Pb is more common (or at least around here), but the cables are always red green and blue regardless.

The conversation is getting confusing to follow (eg "running component into a Software encoding card and RGB (which is the same as connecting to a computer montior) from the PC to the TV", probably means composite in and component out? not sure) with this mixup. I don't know of any capture cards that capture component video, but they may exist?

Hi Jawbroken,

Yeah you are right (at least from me) when I said component I meant composite (the single cable that carries Video Signal and has a male RCA plug on both ends)

Sorry about the mixup, I am always getting the two confused!!

My HTPC connects from my video card to my HDTV via RGB or VGA if you like. Connects in the same was as a PC connects to a normal monitor.

What I meant before was that when I ran composite signal from my STB into a Software Encoding card (namely a V-STREAM XPERT PCI 100) and from there RGB to the HDTV via way of the Video Card (ATI X800 PRO 256 MB) I actually get better PQ than taking the same composite signal and running into the PVR150MCE with it (same connection from the HTPC to the HDTV).

The V-Stream does add some noise to the picture but straight away you can see that this configuration is as good PQ as using composite straight from the cable STB into the HDTV.

The whole gist of which is to say that I am getting crap PQ with my cable channels from the PVR150MCE :shock: