Matrix Reloaded - methods to remove edge noise??

[Superturtle]

Here are the screen shots, encoded using Lanczos @ slow-slowest, 640x320, Bidi, 1364kbps. How could I go about cleaning up that edge noise around Trinity's figure?

http://home.golden.net/~blehto/matrix1a.bmp

http://home.golden.net/~blehto/matrix1b.bmp

[Sharktooth]

Next time use PNGs in place of BMPs...
However the pic looks too blurry (?).
Maybe you used some kind of sharpen after a blur/denoise filter.

[len0x]

btw, is it just me who noticed that AR is not right on that picture...
even if it's anamorphic encode, still not right...

[jggimi]

The images in the links are 640x320, or 2:1. That's an odd aspect ratio for this content.

The film was shot on 35mm and printed in Super 35 (anamorphic) and 70mm IMAX DMR (horizontal), both with an aspect ratio of 2.35:1. The widescreen R1 release is also 2.35:1. The fullscreen R1 disc is 4:3, or 1.33:1, Pan & Scan is assumed. I don't know about other Warner Home Video releases in other regions.

[Superturtle]

I got that resolution I think because I encoded the movie using the 1:1 option. I believe I read in another thread that checking this would end up giving me the resulting movie with the original resolution settings of the movie...or something like that. Should I never use 1:1 and always check of 16:9 and would that affect the outcoming quality of the film...newb questions here!!

What would be a good sharpen filter to use per example, I'm guessing there are quite a few out there?

[Sharktooth]

Yep the AR is incorrect, however he clearly used too much blur filtering then tried to gain some details with sharpen. The results are the pixelated edges and washed out image.
Suggestions:
- Remove ALL filtering
- Use the correct aspect ratio without resizing (croping some lines is better) keeping the highest resolution possible (640 is too low)
- Dont use PSY at that bitrate
- Use QP if you wanna squeeze some extra details but "beware of the artifacts"

[jggimi]

Your choice of resizing filter will affect sharpness dramatically. From the choice of resizing filters in Gknot, Lanczos is the sharpest, and if that's what you've used ... the problem comes from something else in the process.
-----
A commercial DVD's video will have a fixed resolution of 720x480 when NTSC, or 720x576 when PAL. These video streams do not have square pixels like a typical video for display on PC. Instead, they have a rectangular shape, and there are two possible shapes. This shape is called the Display Aspect Ratio (DAR), and is in both in the .IFO file and in the MPEG-2 stream in the .VOB set. The value will be either 16:9 or 4:3. That's because these are the two standard shapes for television screens. (Sometimes those two fields disagree, which causes confusion. AFAIK most standalone DVD players use the .IFO value.)

But films are made in all sorts of aspect ratios. And, as an example, neither 16:9 (1.85:1) nor 4:3 (1.33:1) match Matrix Reloaded (2.35:1). This is why you see letterboxing as part of the video stream.

A DVD production company may choose either DAR, regarless of the aspect ratio of their content. The difference will be the amount of letterboxing. Obviously, widescreen films have less letterboxing when the DAR is 16:9, so more detail is transferred. But there are many widescreen films which have DARs of 4:3.

DVD producers often describe 16:9 DAR discs as "Anamorphic Widescreen." The term anamorphic comes from film photography, where anamorphic films are photographed or projected through special lenses, as the image shape on film is a different shape than the projected or photographed area. If you think of a PC display and its square pixels, 4:3 DAR is also anamorphic, since the shape of the image must be changed when you display it on a software DVD player.

When you select 1:1, you are asking Gknot not to resize to either DAR. It is most typically used with content that has square pixels, or content you do not intend to resize during encoding. And, if you use Gknot to create 1:1 AVIs from content that has non-square pixels such as DVD, you must use an AVI player where you can restore the DAR, such as ZoomPlayer or BSPlayer.

[Superturtle]

Thanks for the information. When I encoded this I didn't have any filtering except for lanczos resize, so all I should do is just resize to the max which would be 704x288 from what Gknot gives me after compress test?

And jggimi, does this mean that I should input the aspect ratio of 2.35 in the "aspect ratio" field under the crop setting in Gknot?

Thanks.

[Sharktooth]

Originally posted by Superturtle
... When I encoded this I didn't have any filtering except for lanczos resize...
Uhm. Make sure you didnt select the DivX integrated preprocessing.
The pics looks too blurry to me (but maybe its due to the resize?). I encoded Matrix Reloaded @1135 bits/sec with DivX 5.1 and the final result looks much sharper than yours.
Maybe i can post some pics later.

[len0x]

Originally posted by Superturtle

And jggimi, does this mean that I should input the aspect ratio of 2.35 in the "aspect ratio" field under the crop setting in Gknot?


The rule is simple - you should always choose between 4:3 and 16:9 and see which one look less distorted. Then do autocrop & smart crop. And you don't have to change AR manualy.

Btw, which moment of the movie is that (time point at least in minutes or even better frames). I just did it with 5.1.1 and can post links to exact the same frame.

[jggimi]

And jggimi, does this mean that I should input the aspect ratio of 2.35 in the "aspect ratio" field under the crop setting in Gknot?The most commonly used Gknot method is resizing to square pixels from commercial DVD source. That means you would select either 16:9 or 4:3 as the input pixel aspect ratio, since those are the only possible DARs. Removing letterboxing from the content will create an image in square pixels with a resolution that matches the original aspect ratio. However, codecs and colorspaces (and sometimes video cards) have resolution restrictions, so there are limits to how granular resolution can be. This is why Gknot defalts to width/height divisible by 32/16 pixels. These values produce small aspect ratio errors, so you will likely not see an aspect ratio of 2.35:1. But you will be able to get close.

As I mentioned before, I would only use 1:1 on content that had square pixels. I have made DivX encodes of DVD source without resizing. When I have done that, I neither cropped nor resized, and kept the original resolution (720x480, which with square pixels is 1.5:1). But to view it, I used BSPlayer and set the aspect ratio to 16:9 or 4:3, as appropriate.

[Superturtle]

Thanks guys for all the feedback...Lennox, the frames for those stills in virtualdubmod are 2435 and 2534. And lennox or Sharktooth, if it's not too much trouble could you tell me what you set up differently than mine so I can get an idea of what I did wrong, I'd appreciate it.

Thanks

[len0x]

Actually I don't find those images to be blury whatsoever. It's normal divx5 stuff (it does blur the picture indeed, but only because H.263 matrix is used within). That's why I like it.

Edge noise will not disappear unless you put more bitrate in. If you want to have sharper picture with divx5 you can enable PSY (fast) + preprocessing (Light/Medium) and compare. Picture will be sharper but might have even more noise in it.

P.S. and you will have better edges if you use proper AR as well...

[Sharktooth]

Well i used slowest mode + light preprocessing + PSY (fast)+ QP but it was done with DivX 5.1.
PSY has changed between 5.1 and 5.11 so i dont think compressing the movie with 5.11 with the same settings will give the same results as 5.1.
I had good results with WMV9 too but at last i've chosen DivX for the final encoding (only coz slowest mode is still faster than WM9 at maximum quality).

[DigitAl56K]

Originally posted by Superturtle
Here are the screen shots, encoded using Lanczos @ slow-slowest, 640x320, Bidi, 1364kbps. How could I go about cleaning up that edge noise around Trinity's figure?


Turn on de-ringing/full automatic pp adjust.

[len0x]

Originally posted by DigitAl56K
Turn on de-ringing/full automatic pp adjust.

it has no effect in vdubmod afaik...

[Sharktooth]

Originally posted by len0x
it has no effect in vdubmod afaik...
Enabling Directshow in Virtual dub 1.5.9 should do the trick with post processing...

[JensG.]

Originally posted by Sharktooth
Well i used slowest mode + light preprocessing + PSY (fast)+ QP but it was done with DivX 5.1. If you encoded with QP, then it was not slowest mode! Slowest mode is disabled when QP is checked. But 5.1 did not tell you!

[SeeMoreDigital]

Superturtle,

Can you please confirm if your DVD source is PAL or NTSC?

Can you also confirm if you do want to generate an 'anamorphic' encode - which should appear all squashed up on playback, prior to you selecting otherwise.

Or do you want to generate a crop and resize encode - which should appear at the correct aspect ratio, when played back!

Cheers

[Superturtle]

My source is NTSC and I want a crop resize encode.

[SeeMoreDigital]

Originally posted by Superturtle
My source is NTSC and I want a crop resize encode. OK then.

I assume that you want to view your encode specifically on a 4:3 PC monitor. And that you don't want to fiddle about with your media players settings to adjust the aspect ratio.

If so, it's crucial that you crop and resize your encode to the correct aspect ratio by selecting the correct image pixel frame size (resolution). And as others have already mentioned, 640x320 is not the correct frame size.

Your source has been identified as being 2.35:1.

But I'm afraid your (640x320) encode is 2.00:1 (640 divided by 320 = 2 or 2.00:1).

So, if you want to keep 320 as your height then you will have to select 752 pixels as your width (752 divided by 320 = 2.35 or 2.35:1).

If however you want to keep 640 as your width then you will have to select 272 as your height (640 divided by 272 = 2.3529 or 2.35:1).

I hope that helps you a bit more.

Cheers

[Superturtle]

I do watch the movies on my pc but also I send them out to my tv as well which isn't 16:9 and I like to watch the movies in there original format. My question is why does GKnot give me an output resolution of 704x288? Wouldn't the proper rez for 2.35:1 be 704x300?
:D

[jggimi]

As I mentioned earlier, there are limitations on resolution settings. These limitations are due to codec, colorspace, compression technologies, and video card requirements. Because of those limitations, Gknot defaults to resolutions divisible by 32 for horizontal resolutions, and 16 for vertical resolutions. Keeping those values are recommended.

In this particular case, 300 is divisible by 4, while 288 is divisible by 32.

But I wouldn't worry too much over this. The method recommended for square pixel resizing is to be sure you've selected the proper DAR, which is 16:9 for the "anamorphic widescreen" release. Then crop to remove letterboxing, usually with Gknot's Auto Crop. If you follow up with either Smart Crop Left-Right or Smart Crop All, you should end up with an output resolution that uses square pixels, and an aspect ratio close to 2.35:1, though it will not be exact, and Gknot will display the calculated difference to the ideal.

In addition, there will be some slight differences in the results depending on whether you leave the ITU standard box checked in the Options tab or not.

[Sharktooth]

Originally posted by JensG.
If you encoded with QP, then it was not slowest mode! Slowest mode is disabled when QP is checked. But 5.1 did not tell you!
Yes. Thats true, i've checked it with 5.1.1.
So probably the encode was made in standard mode even if i selected slowest from the DivX panel.