Observations on Video Quality

[eruji]

Lastnight i actually sat down and tried to get a handle on the differences of the video codecs.

here are my specs:
winxp
pentium 800
hauppauge pvr 250
radeon 9000 (catalyst 3.6)
sagetv (1.4.10) set to capture DVD standard quality 3.25gig hour
m-audio revo sound card
regular cable tv
svideo out to a 27" SD Sony

i have the following video codecs installed on my machine:

intervideo (21154 latest from hauppauge website)
cyberlink (power dvd 4)
sonic cinemaster (TheaterTek latest)


intervideo: this codec looks the worst with out of all the codecs. Any scenes where there is a pan, i could see it pixelate , almost like it would look in focus and then out of focus. Looks absolutely horrible. watching a show with scrolling text is almost unbearable. I should mention that i do have the hardware acceleration turned on in the registry. And that i also can not change the deinterlace setting to anything but default or i get a direct x error.

cyberlink: this codec looks very acceptable. however the main problem that i have is that sage seems to have random lockups. Within 10 minutes of changing to this codec sage froze.

sonic cinemaster: This too looks good, however i did have random lockups on this one too. The strange thing is that my aspect ratio would change. i tried all the settings in sage for , use source, fill , force 4:3 etc and it would not affect it. i think it has something to do with playing a dvd in Theatertek and then shutting it off to watch tv and the codec remembers that last aspect ratio.

anyhow, being totally frustrated with my results, because the most stable being the intervideo codec was the worst looking. i remember reading that you should use the VMR setting unless it gave you trouble, then you should try the Overlay. I switched to Overlay, and instantly the intervideo codec looked great! no more choppyness and blurry text scroll. Im finaly satisfied with my picture quality. Has anybody else noticed the drastic difference in PQ with this setting change?

[mlbdude]

I have the same video card and with VMR or Overlay the Intervideo codec is not that great. I think it is mainly its deinterlacer that is poor though since it is the blurry and smeary effects during motion scenes that I don't care for. Picture quality seems almost as good as the Elecards on my TV but since its deinterlacer is so bad for my normal TV I can't use it. I have heard of people with digital TV's that are happy with it though.

[eruji]

I updated my pvr 250 drivers lastnight to the lates from the hauppauge website, using intervideo codec and Overlay.

looks great, (with the registry hardware encoding enabled) .

i updated it because i was getting the SAP bug and i wanted to record Friends. No SAP now and the picture looks better than it ever has. Also setting the video proc through the registry. now i feel i have a really high quality pvr system. I watched Conan OBrien this morning just to check the quality, to make sure that i wasnt over reacting to the changes from the previous night and i still cant believe how much better it looks. Even when i used to watch my directivo Conan episodes they looked very blocky and a ghosting haze was always around conan during his monologue. I guess because he so pastey white against a dark blue/black background. But with my current settings, its the best my tv has ever looked.

[madpoet]

When you say you set the video proc. through the registry, what are you referring to? I have the same codec/reg hacks, and it's a really ugly picutre for me .

-MP

[mlbdude]

It depends a lot on what you are displaying the video one (TV type). If you give some hints as to how it looks bad maybe we can help you clean it up.

[madpoet]

Sure... using an ATI 9500Pro with the component dongle and Powerstrip. I've got the WinTV250 tuner card and the latest non-beta version of Sage. On both a 480p and 1080i desktop I get a lot of blockiness, especially with things like sports or other high-motion activites. I tried the dscaler plugin with a couple of different settings and it didn't seem to noticably improve things. I have capture settings at 3gb I believe. Other than changing the codec to Intervideo and adding the DxVA reg hacks, I haven't touched anything else for quality settings. Any suggestions are appreaciated . I'm comparing this to the pictur quality from the svideo of my ReplayTV. Admittedly that is a soft picture, but it doesn't have the blockiness and pixelation I get from Sage.

[mlbdude]

I found the Intervideo codec with registry hacks to display the macroblocking more than the other codecs. Try some of the other decoders. The Elecard one is avialabe for a free trial. I use that with DScaler for deinterlacing.

How does Sage look when using the SVideo out of your Radeon? I only ask cause you mention that the Raplay image is soft. Perhaps the blocks were being drowned out by the lower resolution output?

Also, try the DVD encoding profiles 3.x gives good quality. I can not see macroblocks at all on my standard TV, but I am sure a nice setup would show all kinds of defects in the image.

[madpoet]

Unfortunately my Radeon does not have S-Video out (never thought I would say those words!). I'm outputting to a 57" widescreen HDTV so artifacts are in fact easier to see. I tried the elecard with dscaler and wsn't terribly impressed.

-MP

[mlbdude]

Sounds like your problems are with the encoder and not the decoder anyway. All you can do to elimate blocks is to encode at a super high bitrate. If you have only one tuner, I would also suggest upgrading to the latest drivers from Hauppauge using their install instructions if you have not already. I hear they help.

You may want to adjust your brightness/sharpness etc. to see if that helps hide the blocks.

[madpoet]

Brightness/sharpness within the software or the TV? I've tried encoding at the highest bitrate, and it didn't help. I've got the latest Hauppage drivers also.

-MP

[mlbdude]

Brightness/Sharpness with the encoder. You can adjust the levels in Sage (I think) or you can use the registry settings found in a bunch of threads in the forums. I think you have to do the registry settings anyway for them to stick.

[eruji]

Well, its been a few days since ive updated to the latest pvr drivers (21226). The PQ has been great, however ive noticed that when i change the channel i get a 1-3 second stutter and or pause before the video catches up with the audio. It will intermittantly do this in the middle of watching a program as well. I dont recall it doing this before. Also a bigger problem is that sagetv keeps locking up. im not sure why. just kinda random, its locked up at least everyday since ive done the update. Im thinking about trying some older versions of the pvr drivers. Does anyone have advice as to which version i should try? Or does one version work better for someone and not so good for another?

[salsbst]

I'm experiencing no stability problems with the 1.7.21199 drivers: http://www.shspvr.com/forum/viewtopic.php?t=3099

[Mike Young]

Is there a quick way to see what versions of the various drivers one is running ?

mike/

[DFA]

My observations have not been good. I have the PVR-250 with latest Sage and Hauppauge drivers. I have not installed the Hauppauge application as I saw no need but perhaps I should in order to set some things up for the encoder. I place no blame with Sage since they are not fundamentally responsible for PQ: this is a function of the HW encoder and SW / HW decoder.

My system is an Asus A7N8X; ATI 9500 non-pro; 512 MB Corsair Dual Channel RAM; 120 GB 7200 RPM 8 MB buffer Maxtor HDD; XCard w/ PDI hookup to Connexant 878A based capture card (Zoltrix); DVI out to Samsung HLM507W DLP.

I have tried various decoders (WinDVD 5.0, Elecard and the default non-css WinDVD / Hauppauge). I have also used the XCard through Dscaler for decoding. Finally, I played some of the *.mpg files directly through XCard / Dscaler without Sage / Hauppauge in operation.

Results: Pretty much the same, give or take a little: OK as long as no one moves!!! Otherwise, everything goes blocky, blurriy with motion artifacts. Can't seem to get decent deinterlacing either. Today I was watching a guy with pin stripes on his pants and jacket (River Rat; Brian Denehy). Even not moving, the moire effect was horrible.

I have come to the conclusion that the issue is in the encoding since a direct play of any of the *.mpg files through Xcard / Dscaler looks poor no matter what Dscaler filtering and processing I choose. XCard/PDI/Dscaler is about as good a MPEG decoding as you can get for film and video based material.

I have been encoding at "Best" 3.0 GB/hr. Tried "Great" at 2.0 GB/hr. Nothing really seems to really help drastically. I have set the cluster size to maximum for the PVR partition (100 GB). Color, brightness and contrast problems as well.

So ...... are there some registery settings for the Hauppauge encoder that I should set to optimize the performance? Should I install the Hauppauge application to manipulate some things? Is there a thread here or somewhere (SHS forum) where Hauppauge reg. settings are dicussed? Anyone with something similar to me (equipment wise) that has no complaint that can / will export the "hauppauge" registery key?

I've got to clear this up. The wife does not consider it watchable at this point and only complains (and she is not that critical about PQ). I know it is not the source because the source is an svideo feed from the Scientific Alantic digital STB. The svideo output from the STB goes to a high quality wide band, professional grade, svideo distribution amplifier (Kramer) for splitting to the PVR-250, my old VCR and to the svideo input on the Samsung DLP. When viewing the same svideo source on the DLP (bypass HTPC PVR), everything is OK (as good as cable gets anyway; the higher channels are always better from the STB; in other words, totally watchable).

Anyone have a clue for me?

Thanks,

Dane

[mlbdude]

I am not sure what kind of cable you have, but maybe you should look into using a PVR system from your or another digital cable provider? Those systems don't compress the incoming signal and just store the already compressed data for playback. Since the Hauppauge cards compress the signal to MPEG2 you are always going to get decreased image quality and macroblocking at times.

[DFA]

As stated, the svideo feed is ok when viewed direct to DLP. The cable is Brighthouse, digital and analog. I also have the analog RF hooked to the PVR-250 as well as the DLP. Again, the PQ from HTPC PVR would make a train take a dirt road.

When you say macroblocking, are you refering to Macrovision?

I would expect compression and decompression of any signal to suffer some degradation. But if what I'm seeing is as good as it gets with MPEG2 technology, then DVD's would look much worse than VHS. No, something wrong with encoding / decoding process.

DFA

[mlbdude]

Well, if you are not sure what macroblocking is then maybe there is something that can be done with your settings . Post some screen caps with examples of the issues you are having so we know what you are talking about exactly.

[DFA]

Seems to be a common complaint. Even from yourself as earlier stated in this thread. Motion problems in particular, streaking with artifact tails and "macroblocking". But instead of macroblocking, I would describe it more as macrosplotching or blotching which can be seen as an overall disturbance over the entire screen that sort of "crawls" around. This is also most evident when things are panning. As said before, as long as nothing is moving, the PQ is acceptable (considering the source and the process).

Also, color saturation, hue, contrast (black level) and brightness (white level) are definitly out of whack. If these things were closer to home, the rest might not be so pronounced. I see color controls within the Hauppauge registery. Are there any settings for these that this forum has considered to be more or less optimal / generic? The defaults are definitly not good but I'm not even sure if these controls have impact on the encoding side anyways.

The reason I'm focused on the encoding side is because of the PQ when viewing any of the *.mpg files that have been encoded by the 250 through XCard/PDI/Dscaler. Garbage in, garbage out. No deinterlacer or filter can correct something that is badly encoded.

DFA

[mlbdude]

Try this for setting the color settings.

http://forums.sage.tv/forums/showthr...ight=sharpness

Make sure Sage is closed completely when doing this and be warned that I have yet to be able to get these to stick completely (or the setting I see in Sage are not really what is being used).

I have used Tivo and Replay PVR's before and what I have with the Hauppauge is just a notch better. However, none of the above solutions provided what I would consider anything other than good video quality (7 out of 10). You will notice it even more with a DLP.

Good luck!