I suggest trying both and comparing . I was very surprised at how different the results of my last test were...

0 and 0.

Same here. I forgot to say that on my previous posts.

-kwag

@SansGrip and Kwag,

My spoilage settings are 0 and 20 the template default. I sure
wish I could get on the same page as you guys. I bet you both
are using settings that most, if not all, of us are unware of and
that's why the samples look so great and we can't duplicate them.
I'm vasilating between KVCDx3 CQ and CQ_VBR. Blockbuster
dither set to it's highest shows no effect with CQ at any setting.
This is very frustrating I wish I could duplicate Kwag's great
looking samples once and know how it was done step-step
to get the same results

-black prince

There's something wrong there black prince
If you set to something like this: min_detail=1, max_detail=10, variance=50 you don't see the effect

-kwag

We're on the same page. Just maybe not the same sentence . I'm starting to think that there are no "best" settings, only settings that are best for a particular source. For example, I had no idea it would be possible to fit Minority Report (2h20m) on one disc at 528x480, but I managed it with CQ mode and it looks really good, much better than 352x480 CQ_VBR. This is mostly because it was filmed in Cinemascope, i.e. 2.35:1 aspect ratio. Lots of black means lots of compression .

Right now I recommend CQ_VBR for 352x240 and 352x480 with noise or dither, and CQ for 528x480 and 704x480 without noise or dither. With CQ mode I use a spoilage of 0 0 -- I don't remember precisely why, but I know it gave the best results in one set of tests I did.

Aside from that I believe that the correct preprocessing is important for good results. I'll sometimes increase smoothing significantly if I'm having trouble getting something down to size. I find the resulting increase in CQ/CQ_VBR level compensates for the sharpness you're taking out.

I also find bilinear resize to be overall the best method. It's recommended by many people when reducing rather than enlarging, and is the most compressible of all the resizing methods.

I've not tried dither with CQ, but I know that noise doesn't have an effect until CQ goes over about 80.

Perhaps kwag could post a step-by-step along with his next sample, then we could all learn from it. I don't think mine look as good as kwag's, either .

Ditto! Ditto #2 I DO see effect using dither even at 528x480. I will later tonight . I'm multitasking between the computer and real life ( wife and kids ! ) today.

Edit: I still see a small advantage by using a very small "dither" even at 528x480. Something like this: Blockbuster(method="dither", detail_min=1, detail_max=10, variance=.4, seed=1)

-kwag

@SansGrip and Kwag,

Thanks, for the explaination. It makes sense. One solution doesn't
fit all. Each movie seems to be different in terms of settings and
testing. The suggestions you made are very helpful. It seems each
movie requires expermenting to get the best picture quality. I
intend to buy "Signs" next and will put some of your suggestions
to good use.

-black prince

SansGrip,

Are you using "Fast" motion estimation, or are you using "High quality"

-kwag

I'm using high quality because I found it gives smaller file sizes. I've yet to do a visual comparison though.

I think I would make two sets of samples, one with CQ_VBR and one with CQ. This way we know for each source what works best, and it should be possible to develop some guidelines for what kind of source requires what method of encoding.

As I promised earlier today, here's my latest sample. First, here's the script used:

Here's the sample: http://www.kvcd.net/k-19.cq.65.5.hig...1.dither.5.mpg

This was encoded at 528x480 using CQ mode with a value of 65.5 ( target for one CD-R ) and using "High quality" on motion estimation. Audio was encoded at 112Kbps with "Surround 2" ( Prologic II ). This sample includes audio
The complete multiplexed .mpg file size is 792,421KB

SansGrip,
Let me know how this sample sound on your new receiver

-kwag

Just a counter-point to the bilinear resize... Lanczos gives me _much_ cleaner results, with only minimal loss in compressibility. An 11.68meg clip done with Lanczos only dropped to 11.57meg with bilinear. Granted, this adds up slightly over the course of a 700meg movie, but the tradeoff wasn't enough to give up the sharpness and clarity provided by Lanczos. Granted, this may be impacted by my source, but don't throw out Lanczos yet. (I didn't try substituting Lanczos with bilinear+blockbuster sharpen).

Hi Daagar,

At least at 528x480, which is already a high resolution, lanczos created slightly more visible artifacts than bilinear. Also, my CQ value was stepped up almost 2 point for the same target file size by changing to bilinear. I can clearly see the difference around objects and on dark backgrounds. At least that's the result I got by comparing both samples, one with lanczos, and the other one with bilinear on the movie above.

-kwag

I see the same thing -- more "stepping" in diagonals, and I find it tends to overemphasize any edge enhancement already applied to the DVD, while bilinear hides it.

Looks (and sounds ) very good! I do notice some "flashing" blocks in backgrounds, but it almost certainly wouldn't be noticible on the TV unless one was looking for it specifically. Hardly any Gibbs...

@Kwag,

I finally noticed Blockbuster dither at variance=50, but at
variance=.4 is very subtle. I had to magnifiy the frame and then it's
not immediately noticable.

Are you using Headac3he or BeSweet for "Surround 2 (Prologic II)".
What happen to "Dual Channel" in Headac3he?

BTW, the sample clip was very good!! With very little Gibbs for the
file size created.

@SansGrip,

I took you advice about trying both CQ and CQ_VBR. The source seemed
to determine which process came out better. Guide lines for which to
use based on the source would be nice. Using bilinear, fluxsmooth,
and dither, compressed the final file size by 40%, so the video+audio
fits on 1 CD with great picture quality. Lanczos looked better, but the
compromise between file size/picture quality was my final decision

-black prince

HeadAC3he Dual Channel encoded as "Surround" 2.
There's a (Stupid) debate at the "Other" forum about "stereo" or "dual channel". I use dual channel because I don't want ANY variations from one channel to the other. In stereo, there are, and this variations "correlations" mess up surround signals on some receivers. This has been reported before by a couple of users. Using dual channel, their problems were over .

-kwag

Touche... my original test was done with CQ_VBR. I redid the test and you are correct, with bilinear there is a greater amount of compression allowing a higher CQ value. Nice.

SansGrip,

Sorry for taking too long to reply - the keyboard of my computer at home just died and so I just could test the new DLL now that I'm back to work

The new DLL works OK with the code I posted before, I didn't even had to recompile.



I'll create a new post in the FitCD forum, with the link to your DLL and my Delphi code, so it's both easier to Muaddib to pick it and we stop polluting the file prediction forum

kwag --

I've noticed this a few times testing the notch matrix. I think this might be a symptom of overflows caused by using values less than 8:



If you look in the highlighted area (save the image and zoom in with your favourite viewer) you'll see a red-and-green striped box and to its right some purple and yellow streaks.

I also find the lower grab to be somewhat less sharp than the upper. Look in particular at the forehead of the guy on the left.

What do you think?