AVS Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
1,358 Posts
Discussion Starter #1
Hi to new and old members



I've been out from the forum for quite a while, and technology and tweaks have been moving up, so I would like to check couple of things in my new setup.


Hardware: Optoma HD80 1080p projector via DVI, DaLite 133" 1.5 gain screen, seating distance 5.5 m, some 17 ft, Dual Core 3.0 Ghz CPU, 2GB 800 mhz DDR2 RAM, Nvidia 8800 GT, LG Combo drive, Intel HD Sound (Realtek DD HD and DTS HD via Multichannel analog output, other SPDIF passthrough), 7.1 sound setup to Onkyo receiver, Dali Royal speakers for 7 ch, MK 12” sub for LFE, solid cables (forgot the brand/model).


OS and Drivers: XP Pro (all updates, including last Direct X and NET Framework 3.0) Nvidia last official WHQL drivers 169.21 (no AA or AF settings active), Realtek 1.84 drivers. I have Vista 64 bit as well, but did not have any time to play around with that one.


Software: DVD - TeaterTek 2.6, FFDShow MMX (Dec 07 or Jan 08 version), Avisynth 2.5.8 Alpha 2; Blu Ray/HD DVD - PowerDVD Ultra


Goal: The best image and sound quality


I am quite happy with how the whole setup performs at this moment. Quite a feast for the eyes and ears. But I would like to see if it can do better that this. As noted before, I have been out of tweaking business for a while and unfortunately don't have much time to spend on tweaks as well.


Blu Ray/HD DVD - Thinks seem quite OK with the current set-up. Image quality seems to be solid. I tried couple or older Nvidia drivers (although for 8800 GT being recent card choice is not overwhelming) and things were worse than with the current WHQL. Overall, image quality for Blu Ray is almost at par with PS3 which is the current leader. I suspect that software and driver updates will enhance the image quality in the future. Not sure what more to do at this point. I did not use HD DVD so far as HTPC is fairly new.


Possible enhancements. Sound is working great, so I don’t know what else one could do at this time, especially when the goal is to get new HD audio formats out. As far as image quality, I read couple of different stories on whether Vista would improve experience, so not sure what is the current thinking. Also, the old story Nvidia vs. ATI seems to be unsettled. In the old days, driver tweaks did quite a bit, not sure if that is true nowadays. Any other suggestions are wellcome.


DVD - Have about 600 titles, so although I started replacing my favorite movies as HD versions become available, DVDs are quite essential. Also, in my area there is not much in terms of HD rentals. I use fullscreen mode and VMR9 plus FFDShow/Avisynth video post processing in YV12 colorspace (YUY2 seems to cost a lot of CPU and not sure it is worth it). It seems that Limited Sharpen is the preferred way these days to tweak the image. I tried and it is quite good, but after spending some time tweaking, this looks better to me:


Levels: Input 16-235, Output 0-255 (arguably this extends video space to full range, test patters show with eliminated below-black and above-white)

Avisynth Spline64Resize 1280x720 (this is new in 2.5.8 version, was not there before)

FFDShow aWarpSharp Depth 64, Threshold 0.99, Blur 0 (need to play more with this)

FFDShow Sinc Resize 2016x1134 (or 1920x1080, not sure yet), luma&chroma sharpen 0.6-1.2 depending on the title (need to play with this as well)


Test patterns are showing great, as well as reference quality DVD transfers. Did not play with lesser DVDs yet. This maxes out the CPU, but still provides smooth 1080p 24 or 25 fps playback. It might be the 133” screen with 1080p projector, but I have never seen DVD image done so right.


Possible enhancements: Probably same as questions as for Blu Ray/HD DVD. In DVD area obviously FFDShow/Avisynth tweaks can bring enhancements, so the question is if anybody has a better recipe? Any other suggestions are wellcome.


Thanks for your input and cheers,


V
 

·
Registered
Joined
·
1,358 Posts
Discussion Starter #3
Not sure I want a reference 640x480 16-235 DVD. More like reference as it compares to the original film master. The idea is to expand 16-235 and map to 0-255 range. Whether it provides a benefit, it is more difficult to say. Nvidia drivers can be foreced to output 0-255, so that should be OK. Optoma HD80 keeps and displays that range which is easy to see on test patterns. Test patterns tell me that projector shows entire useful range of signal. In this case, it should for sure use its full contrast range, while in 16-235 it might be saving the low end and high-end of contrast range to show data that we are not really supposed to see. A/B real time comparison would show if there is difference in the image. Whatever this does, looks a bit better to me than no level tweak. But as I said, difficult to tell without A/B. Sony has superwhite output on its PS3, and I think this works on the same principal.


Any other suggestions?
 

·
Registered
Joined
·
442 Posts

Quote:
Originally Posted by vpopovic /forum/post/12886355


Possible enhancements. Sound is working great, so I don't know what else one could do at this time, especially when the goal is to get new HD audio formats out.

What are you using for HD sound now, SPDIF or analog outputs ?

Quote:
DVD - Have about 600 titles, so although I started replacing my favorite movies as HD versions become available, DVDs are quite essential. Also, in my area there is not much in terms of HD rentals. I use fullscreen mode and VMR9 plus FFDShow/Avisynth video post processing in YV12 colorspace (YUY2 seems to cost a lot of CPU and not sure it is worth it). It seems that Limited Sharpen is the preferred way these days to tweak the image. I tried and it is quite good, but after spending some time tweaking, this looks better to me:


Levels: Input 16-235, Output 0-255 (arguably this extends video space to full range, test patters show with eliminated below-black and above-white)

Avisynth Spline64Resize 1280x720 (this is new in 2.5.8 version, was not there before)

FFDShow aWarpSharp Depth 64, Threshold 0.99, Blur 0 (need to play more with this)

FFDShow Sinc Resize 2016x1134 (or 1920x1080, not sure yet), luma&chroma sharpen 0.6-1.2 depending on the title (need to play with this as well)

We have very similar set ups -- I also use FFDShow upscaling for SD DVDs -- I agree that LimitedSharpen filter provides best picture quality and I am going to try your script tonight
-- why would you use 2016x1134 rather than 1920x1080 ?

Quote:
Test patterns are showing great, as well as reference quality DVD transfers. Did not play with lesser DVDs yet. This maxes out the CPU, but still provides smooth 1080p 24 or 25 fps playback. It might be the 133 screen with 1080p projector, but I have never seen DVD image done so right.

I am curious how did you get smooth playback on Nvidia card ? I have 24fps capable projector but when I output 1080/24 I get jerky playback on both HD and SD sources. It appears to be Nvidia drivers issue. I use Forceware 169.21, what drivers are you using ?

Quote:
Possible enhancements: Probably same as questions as for Blu Ray/HD DVD. In DVD area obviously FFDShow/Avisynth tweaks can bring enhancements, so the question is if anybody has a better recipe? Any other suggestions are wellcome.

I really don't see much that can be improved in your set up, sorry not much help here.
 

·
Registered
Joined
·
2,914 Posts

Quote:
Originally Posted by vpopovic /forum/post/12887923


In this case, it should for sure use its full contrast range, while in 16-235 it might be saving the low end and high-end of contrast range to show data that we are not really supposed to see.

It should be pretty easy to set brightness/contrast so it doesn't, especially with a HTPC - there are plenty guides here to do just that.


At the end of the day, expansion doesn't have a big quality penalty with modern video cards, but it's still there. Essentially it's an unnecessary extra step of processing, degrading the quality from the 16-235 original. To my mind the only reason for it is if you can't calibrate your display properly at 16-235 (which seems extremely unlikely given the quality of kit you're talking about).
 

·
Registered
Joined
·
1,358 Posts
Discussion Starter #6
For Dolby True HD and DTS HD or Master you can only use 7.1 analog output. SPDIF would downmix them to DD or DTS, which is not bad, but analog output is better.


You can use higher then output resolution as kind of subtile denoise/blur filter. Your card will have to downscale to output. Not very noticable though.


I use same drivers as you do, not sure what is problem there. 24, 25, 50, and 60 hz all work great at 1080p. Card is 8800 GT and that one is supposed to have new video processing as 8600's, and is otherwise different architecture than 8800.


Let me know if you see any benefit from the resize that works for me.
 

·
Registered
Joined
·
1,358 Posts
Discussion Starter #7
In my view, all the math you are doing latter with the signal should turn better and result be more precise with 0-255 range. You have Avisynth/FFDShow processing, then video card processing where image is before rendering calculated with 128-bit precision (if drivers would permit that), and finally internal processing by the projector done who knows how. End result should be more gradations in the image.


Just my 5c. You might be right that this in not necessary, but expanded range looks better to me, makes me happy, and I am keeping it.
 

·
Registered
Joined
·
681 Posts
where's your 7.1 audio room correction?


the use of multiple room corrected subwoofers is highly recommended.


is your room treated for audio?


. . .and you thought a 3.5 Ghz quad core would be enough. . .
 

·
Registered
Joined
·
442 Posts

Quote:
Originally Posted by vpopovic /forum/post/12888887


For Dolby True HD and DTS HD or Master you can only use 7.1 analog output. SPDIF would downmix them to DD or DTS, which is not bad, but analog output is better.

When I use True HD from PowerDVD through SPDIF all I get is stereo signal -- it is not downmixed to DD or DTS 5.1. Maybe I am missing something in my settings.

Quote:
You can use higher then output resolution as kind of subtile denoise/blur filter. Your card will have to downscale to output. Not very noticable though.

Let me know if you see any benefit from the resize that works for me.

When I had 720 PJ I used superscaling a lot -- I was upconverting 480 SD DVD by the factor of 2 (960), then it was downscaled by video card to 720. IMHO superscaling/downscaling was responsible for 90% improvement in picture quality. When I upgraded to 1080 (not long time ago) I had to change lots of scripts and was pretty happy with just going to 1080x1920 due to high CPU usage. Some scripts I can't even run in 1080, and I have Conroe 6600/2 Gig of RAM. I will give superscaling technique another try.

Quote:
I use same drivers as you do, not sure what is problem there. 24, 25, 50, and 60 hz all work great at 1080p. Card is 8800 GT and that one is supposed to have new video processing as 8600's, and is otherwise different architecture than 8800.

This is wierd -- I have 8600GT card and once I switch to 1080/24 (which is confirmed by PJ, AE2000) I get some strange jerky type of artifacts every 1-2 mins, I have described it on this thread:

http://www.avsforum.com/avs-vb/showthread.php?t=978249


I've read some posts here on AVS where people experience similar type of problem and it was suggested that Nvidia cards drivers have this bug. I wonder if it can be hardware related.
 

·
Registered
Joined
·
1,358 Posts
Discussion Starter #10

Quote:
Originally Posted by Herc /forum/post/12889690


where's your 7.1 audio room correction?


the use of multiple room corrected subwoofers is highly recommended.


is your room treated for audio?


. . .and you thought a 3.5 Ghz quad core would be enough. . .


Audio correction is done by receiver. It is cheap, but good. 7-ch power amp is the upgrade that will come over time.

http://www.hometheaterhifi.com/volum...06-part-1.html


No multiple subs yet. Will probably come over time.


Room is not treated for audio yet. It is also my home office and carpenters still need to finalize their custom work before audio guys come in.


Can't disagree on CPU power. Never enough. However, i must say that Intel Duo 3.0 Ghz is quite powerfull and silent. With Zalman 120 mm fan it stays in 17-25 db range and in my set up that is important.
 

·
Registered
Joined
·
1,358 Posts
Discussion Starter #11
I'll have to check on downmix in Power DVD. I recall that all speakers were active, but it might have been the receiver upmixing it, forgot what was the input signal as I don't use SPDIF for HD audio.


I'd say the more important part of the scaling above are good algorithms (Spline64 is high order, no ringing, Sinc is the purest scaling on math basis, but needs more than original DVD resolution to avoid ringing) and aWarpSharp. Overscaling is less important.


Not sure what is going on with the video card. I did not opt for 8600 as 8800 GT become available. 8600 has 128-bit memory interface which is not overwhelming, but should be more than enough. 8800 GT has 256-bit interface that always gave me more comfort. You could try Quadro FX drivers that support your GPU. While you will not get any Quadro FX functionality, these drivers are usually have more solid implementation of resolutions, timings, and image processing. They are not driven by FPS hunger of GeForce series. One way or another hope you will resolve your issue.
 

·
Registered
Joined
·
1,358 Posts
Discussion Starter #13
Sorry for not following up on audio portions of the questions. I am really interested in getting some input on the video processing issues.


As noted above, I have been away from the forum for quite some time, so don't mind if some of my questions/suggestions have been already discussed and dismissed. Below relates to DVD processing in FFDShow/Avisynth.


Most of the FFDShow/Avisynth tweaks seem to be following the "luma" route. This all started way back when this was the only route due to CPU limitations of the time (this was 4-5 years back if I remember correctly). At this time I wonder if this route is still the right one. Folks seem to be doing most of the processing in YV12, as this colorspace is least demanding to process, i.e. gives you more processing power per CPU cycle. However, there are downsides to that approach as well, mostly associated with downsampled chroma information in this format. The question is whether benefits of YV12 are greater than downsides.


To recap (and please correct me if I am wrong, I did not deal with this in a while), MPEG-2 container is 4:2:0 downsampled colorspace, and the goal is to get to RGB/Y'CbCr (whatever video card drivers will ultimately output) 4:4:4 colorspace output.


The question is where and when to upconvert 4:2:0 to 4:4:4. Current approach seems to leave it to the video card drivers to do a conversion after all the processing in Avisynth and FFDShow has been done. I am not sure that is the best way. While there are various ways to do it differently than waiting for the last moment to upsample chroma, I played around with this one yesterday and it did look better than YV12 route. I really did not have much time to test, but even my wife said this looked better on one movie we were watching yesterday. So the famous wife factor is present here as well.


Zoomplayer 6something Beta

Nvidia decoder (from TT 2.6) - set to output YUY2 4:2:2 (16-bit) format, so part of the chroma upsampling happens here;

FFDShow input - set to YUY2;

Avisynth - don't have exact script on me, but it is something like (I use version 2.6 as this one has better scaling than 2.57, at least IMO):


MT something

ConvertToRBG32

Chromaresample=Lanczos4 (this upsamples chroma from 4:2:2 to 4:4:4 using Lanczos4 angorithm, further tweak could be to let YV12 flow from decoder and upsample all the way from 4:2:0 to 4:4:4 - I used the ordering at first instance, i.e. do it as early as you can, and by the way, all decoders were designed to output YUY2, so it might happen that they downsample when doing YV12 output)

Lanczos4Resize(1280,720);


FFDShow Asharp (optional, but a tiny tiny bit of it looked nice, FFDSHow is recent January MMX build)

FFDShow resize Lanczos tap 3 or 4 (could be Spline as well, it looked quite nice) to 1920x1080;

FFDShow output RBG 32

Haali Renderer

Nvidia 8800 GT with 169.61 Drivers

Optoma HD80 shooting to 133 DaLite screen


The whole concept has not been extensively tweaked, so I'd say there are futher gains to be had. This does take a tool on CPU, so my 3.0 Core Due had to be taken to 3.4 Ghz to handle this. Not sure if more gains could be had with better MT management, in which case limited sharpen etc. could come in play.


The idea behind this concept is to recover most of the info from original DVD material. First thing is to convert to 4:4:4 colorspace as early as possible and do all processing in full colorspace, rather than in 4:2:0 YV12. This is kind of similar to the whole Why FFDShow scaling story. If video card drivers were doing exquisite job (in this case with colorspace conversion), tweakers would be out of business in no time. But there is no fear that will ever happen. Also, the problem here is not only Nvidia/ATI, but time when this conversion happens. IMO it is too late in the process. Second thing is to use the very best scaling to get as much out of the original as possible. That is why up to first megapixel Avisynth is essential. After that (and some optional sharpening on 1 MP image), the idea is still to use very good algo, but at that point we can use less CPU expensive for the remaining megapixel. IMO level of detail after all this has been increased compared to the traditional route, including limited sharpen. How much, that is a difficult one, but I'd say that depends on transfer and color content of the movie itself. It might be just me, or the 133 screen at 1080p. Not sure if this image would appeal to the others, especially folks with smaller screens.


Thought, comments and suggestions are welcome.
 
1 - 13 of 13 Posts
Top