pvr150 picture quality

[lajams]

My recordings, when viewed via the Media MVP, look nearly like the original broadcast. The only difference (as someone stated above) are dark scenes, and there I do notice a bit more grain and loss of detail.

That being said, the recordings look totally crappy when I watch them on my PC. I have only myself to blame for that tho...I installed a free mpeg decoder and it is sub-par compared to the commercially available ones.

[SirJYK]

Thanks Csy.

I have a few more questions if you do not mind me picking your a brain a bit. I am new to this, not to PCs but to video and htpcs.
1) I had this already.
2) I changed this. It was set to 800 x 600
3) I changed this. It was more difficult than expected. I had to go through the control panel to change my primary monitor setting. For some reason, Windows must have priority over the Nvidia software for this setting. At this point, it seems there might have been some quality improvement, but not much.
4) I could not find this setting anywhere.
5) My hardware decoding was set to software, with only 3 options: None, Hauppauge PVR350(puzzling since my capture card is a pvr150), and Sigma Designs Xcard. I could not do what you recommended here. This is where I stopped.

Now here is a dumb question I am sure. With my 7600gs vid card, shouldn't it be doing the hardware decoding? If so, how do I enable it? What exactly is PureVideo and how is it related if at all? Is PureVideo a purchase item?

Thanks for your help!

[ubu]

4) Disable TV-out scaling and anti-flicker. For ATI, enable "video mode", and for Nvidia set anti-flicker to zero (far left on slider).

When I set the anti-flicker all the way to the left, the Windows desktop on my TV starts flickering pretty wildly. With the slider centered, there's no flicker. Is that the trade off? To get optimum MPEG2 playback, you have to sacrifice the desktop usability? Or is my card (MCI Nvidia 6200) just reacting in a non-standard way?

[csy]

I'm never quite sure exactly what people mean by "sharp" or "fuzzy". My picture is actually sharper than my regular TV tuner in that the edges of things are more clearly defined. But it looks like I'm viewing it through a glass of weak tea (or the bottom of a nearly empty glass of Guinness ).

Fiddling with decoders and various settings has improved the "sharpness" and removed any stuttering, pixelation, etc but the picture still appears opaque and "soft". What is confusing to me is that I don't experience the same problem when playing high quality web streams with Windows Media Player or DVDs with PowerDVD. Yet they must be using the same decoders, DirectX and video card settings.

This makes sence - I think
When you watch any progressive format video (eg DVD's and web streams), the video decoder recognises that it is progressive format and does not deinterlace the video (it actually applies 'weave' deinterlacing, meaning no deinterlacing). These videos will appear sharp and clear.
But with interlaced video (eg TV), the video decoder will recognise the video is interlaced and apply your selected deinterlacing method. If it is using software deinterlacing then the only method available is 'BOB' deinterlacing. BOB deinterlacing takes the first interlaced field containing only half the horizontal lines and scales it up (zoom) to full screen and displays it, then it takes the other interlaced field and does the same thing. So in effect you have lost half you lines of resolution. But it gets worse because the fields are overwriting each others space on the screen so you get 2 representations of vertical edges on the screen. So when motion occurs, it produces 'soft' edges on fine detail (hair on someones head) and blurred edges when movement occurs. The way to resolve this is to use per-pixel adaptive deinterlacing, which is only available on video cards (aka hardware deinterlacing). There is a very good description of deinterlacing at:
http://www.100fps.com/

4) I could not find this setting anywhere.

(from memory) Go into Control Panel and open the Display Settings, click on Advanced button, then select the Nvidia tab. This will open the Nvidia sub-menu tabs Select the Nvidia display properties tab which should display the TV icon and monitor icon. Select TV icon and tick 'primary' box and apply setting. Below the icons is a drop-down menu and select 'Device Properties'. This is where the TV-out anti-flicker slider is located. Slide it to the far left (disabling the anti-flicker function) and apply the setting.

5) My hardware decoding was set to software, with only 3 options: None, Hauppauge PVR350(puzzling since my capture card is a pvr150), and Sigma Designs Xcard. I could not do what you recommended here. This is where I stopped.

You are looking in the wrong place, that is the GBPVR playback decoder device setting which should remain as 'none'.
I am refering to the video decoder properties (settings). depending on which video decoder you use, some of them can be configured within the GBPVR config in the playback tab by clicking on 'video decoder settings' button. The only 2 video decoder that I'm aware of that can be configured this way is the Nvidia Purevideo decoder and the DScaler5 decoder. All the other decoders require registry tweaks to adjust their settings. Let me know which video decoder you are using and I'll guide you through adjusting the settings.

With my 7600gs vid card, shouldn't it be doing the hardware decoding? If so, how do I enable it?

Late-model video card have DirectX Video Acceleration (DXVA) for MPEG2 and in now in some cases also for MPEG4/AVC. When enabled on both the video card and also the video decoder, then some of the video decoding is handed-off to the video card hardware to process instead of the CPU. So DXVA capable video cards provide decode assistance but not full decode. Deinterlacing is also part of the DXVA spec, hence providing hardware deinterlacing functionality as per my point (5). Nvidia video cards have this enabled by default, however you also need to enable 'hardware acceleration' on your video decoder settings to make it work.

What exactly is PureVideo and how is it related if at all? Is PureVideo a purchase item?

Purevideo is the Nvidia Purevideo decoder. It is an MPEG2 video/audio decoder specifically designed to provide additional propriatory post-processing hardware processing on Nvidia video cards. However the latest version (1.02-196) is missing this post-processing functionality, therefore making this decoder a normal MPEG2 decoder. IMO, this decoder is the best I've come across and I recommend it. It is not free, you have to purchase a key from the Nvidia website.

When I set the anti-flicker all the way to the left, the Windows desktop on my TV starts flickering pretty wildly. With the slider centered, there's no flicker. Is that the trade off? To get optimum MPEG2 playback, you have to sacrifice the desktop usability? Or is my card (MCI Nvidia 6200) just reacting in a non-standard way?

Yes that is what happens and it is a trade off between windows flicker and sharpness of video. You need the anti-fliker totally disabled in order to have sharp video. Experiment for yourself.

[SirJYK]

Csy,
Wow! Thanks! You are an encyclopedia of information.

1) I did finally find the anti-flicker setting and adjusted it.
2) How do I find out what decoder is being used? Where in the registry would I find this? This machine has a fresh install of WinXP Pro with all the updates with no other DVD type software installed. I will gladly configure this as you see best. Do I need to download a video decoder. If so, which one? I believe you said you liked the PureVideo from Nvidia. After going to their web site, they have 3 different versions: bronze, gold, and platinum with the differences appearing to be in sound. Bronze has standard surround stereo; gold adds digital 5.1; and platinum adds DTS. Which would you recommend? I may try and "acquire" one today. The last 2 times I tried to dowload it from Shareaza, my norton prompted me that I had downloaded a trojan horse and it quarantined the file. If I cannot "acquire" one, I will ante up for it if it is the one you recommend.
3) On another note, recording to DVD using Ulead software, I have a few more questions. I have archived a show twice to DVD; one at medium and one at high recording resolution. I am still experiencing the fuzziness and low light loss of detail equally as bad at either recording setting. Is this related to my settings/decoder or is it the lack of resolution integrity by the software? The files are quite large in my opinion, comparable to commercial DVD size. Not knowing exactly what goes on in this process, I would assume that garbage recorded initially would equal garbage recorded to DVD.

Thanks

[ubu]

The way to resolve this is to use per-pixel adaptive deinterlacing, which is only available on video cards (aka hardware deinterlacing).

Thanks for this excellent description of the actual physical effects of deinterlacing. I'm not experiencing anything as bad as the examples in that link so I presume that my card is doing adaptive interlacing (with Purevideo at least, although there's no obvious way to turn on hardware acceleration with the Intervideo decoder). One more question on this: what is the difference between "Encoder pass-through" and "None" in the Deinterlacing field in the Live Preview Mode section of the Misc tab in GBPVR config?

Purevideo is the Nvidia Purevideo decoder. It is an MPEG2 video/audio decoder specifically designed to provide additional propriatory post-processing hardware processing on Nvidia video cards. However the latest version (1.02-196) is missing this post-processing functionality, therefore making this decoder a normal MPEG2 decoder.

Do you know if/when they will enable this feature?

IMO, this decoder is the best I've come across and I recommend it. It is not free, you have to purchase a key from the Nvidia website.

Actually they do offer a 30-day trial version for free. They don't exactly advertise this fact since it's impossible to find on their web site but you can download it here.

I've just upgraded from 1.02-184 to 1.02-196 in the hope that it would solve the problems I experience with this decoder. It certainly produces an immaculate picture with my new 6200 card (better, in some ways, than my TV's tuner) - sharp, clear and with natural colors. But it takes 20 to 30 seconds for live TV or a recording playback to start, CPU shoots up to 100% initially and then bounces between 80% and 100% and playback will suddenly start stuttering and audio will cut in and out. My reliable old Intervideo non-CSS decoder doesn't produce as nice a picture but its pretty bullet-proof in other ways. Life seems full of trade-offs.

Nvidia video cards have this enabled by default, however you also need to enable 'hardware acceleration' on your video decoder settings to make it work.

Have this enabled for Purevideo so I'd expect to see less CPU load, not more.:confused:

BTW - installed my new card complete with component-out dongle, only to find I'd forgotten to actually buy a component cable. Duh! If I could only get Purevideo to work smoothly, with the component hook up I imagine I could get a near-perfect picture and have something significant to add to the Incredible difference:Nvidia versus ATI thread. (Had to return the ATI 9600 I mentioned buying in that thread after belated googling revealed that my particular ASUS mobo has a reputation for not playing nice with ATI 9xxxx series cards. Seemed to think the 8X card was operating at 3.3v so wouldn't power up. Thankfully I hadn't bought an ATI component adapter yet).

[ubu]

This is turning into a really classic thread, thanks to csy. Worthy of being a "sticky". So, if I might ask another question...

Is there anything to be done about overscan and aspect ratio problems? With the Intervideo decoder I experience serious overscan (cuts off the GBPVR overlay and some of the main menu displays). The Purevideo config has a setting for overscan adjustment (which actually doesn't seem to work with my system for some reason) but I can't find an Intervideo equivalent. I don't experience overscan when using the Purevideo decoder but, instead, the picture is too narrow (black bars at each side). The height is OK though so it doesn't seem to be "underscan".

[upspace]

it is definitely not the capture card. i used to have the same problem with blurry, washed out tv on my philips 100 hz. the picture from the cable directly into the tv is 1000 times better. black is black, egdges are sharp etc.

the problem is the tv out (s-vhs) you are using. unless you don't go digital (dvi/hdmi) or using a (analog) rgb cable you will never get something similar as you are used with normal tv or from even the cheapest dvd player. all the tweaks, codecs or different graphic cards/tv out chips won't help. it is wasted time and money. it is s-vhs which is not as good as any $30 dvd player with rgb out - believe me.

so you have two options:

1. buy a new tv with dvi and/or hdmi (a lot of $$)
2. build your rgb from the analog vga signal. this is easy with ati cards, harder with nvidia chipsets (i personally have the fx5200). check the forum for instructions how to solder your cable (cheap but for freaks)

unfortunately i am also stuck. don't want to buy a lcd tv because i like the brilliant picture from my philips 100hz (still ways better than any lcd/plasma at least for analog signals and here in europe everything is still analog from cable/terestial) and i don't get the rgb cable to work with my fx5200.

oooh i forgot there is a third option: buy graphic card with rgb out (have not found yet here) or check for an external rgb converter box (200$).

i am waiting until the world championship is over because i am sure that lcd tv prices will fall drastically.

cheers.

p.s. just switched from mediaportal to gbpvr. why? gbpvr is doing what it is supposed to do - fast, stable, low resource usage - mediaportal is the opposite but fancier. mediaportal looks nice at the surface but i am doubting that the core architecture is future-proof...

[SirJYK]

Upspace,
When you say the problem is the TV-out, s-video out, would recordings to my hard drive when converted to DVD format exhibit the same characteristics? I would think not, unless there is alot of degradation in the conversion to DVD. So another question has been raised by what you have stated: Is the analog cable signal feeding my TV and my PVR vastly superior to the signal that can be sent via an s-video cable? If it isn't, then I am experiencing, either signal/detail losses through the capturing process, or, my TV is more sensitive to the cable signal, resulting in better quality. Boy, this is confusing. Csy, please hurry up and respond....lol.

On another note, my vid card, Nvidia 7600gs, came with a s-video to rgb output dongle. I do not think this will help me at all since the dongle uses the s-video out on the vid card. An hdmi to rgb would be nice, but neither my tv, nor my high end yamaha(if you can believe that) receiver supports it.

Thanks.

[SirJYK]

Csy,
I got antsy and decided to take PureVideo for a test run. You can download it and run it for 30 days for free. It seems that it improved the quality a bit. I am still noticing washout with bright colors and lack of detail. Richness has improved dramatically. I am still comparing everything to the incoming cable signal on my TV. When I installed PureVideo, I changed the software settings in GBPVR to use it. I did not know how to change the dxva stuff that you mentioned. I am hoping to see sharpness and detail improvement after changing the dxva settings.

On another note, I think there were some interlacing settings on the Miscellaneous tab in GBPVR setup.

I also noticed that the GBPVR window for video is about 10-15 % smaller than the TV picture. When I change the settings to match, that is enlarge the TV output from the vid card, the GBPVR menu is truncated by the amount I enlarged the output. It really doesn't matter except it cuts off the left side of the menu items and we cannot have that! Is it doing some sort of scaling that it shouldn't be doing?

Thanks.