Forcing resolution at non-standard aspect ratio

[replayed]

I'm trying to rip a TV broadcast that was aired in a slightly squeezed aspect ratio, with everyone looking skinnier than they should. This wasn't the standard 16:9 squeeze unfortunately, so it's not just a matter of setting a flag in the stream.

To put it in more precise terms, the rip is coming out by default at 640x368, but to my eyes, the correct resolution looks much closer to 640x340. I'm trying to figure out how to make the rip come out at that resolution.

I searched around this forum and tried to play with settings in the .aspect file. But the rip comes out sized at ratios like 2.35:1 (if .aspect is set to 32:17), and 2.5:1 (if .aspect is set to 2:1), but not the 1.88:1 that I would like to force.

Is there a way with AutoGK to get the exact resolution I want in order to make up for a distorted source, even if the resulting aspect ratio is non-standard?

Someone told me how the modify the Avisynth script to specify the resolution I want [i.e. specify LanczosResize(640,340)]. But of course I can't figure out how to override the default Avisynth script AutoGK generates before it starts the encoding.

I've been a big fan of AutoGK for over a year now. I think I may have finally found a problem that calls for some other ripping software. Am I correct?

All suggestions would be appreciated.

[CWR03]

One of the simplest methods to determine resolution and how much to crop is to install the full Gordian Knot, then open the file there. Under the resolution tab you'll be able to see what your changes will do immediately, and you can enter those same parameters directly into AutoGK for the same result.

[replayed]

Thank you for the reply, but I think you may be misunderstanding what I'm trying to do. This has nothing to do with cropping. The image is being perfectly cropped.

The problem is that the source itself is distorted (squeezed). What I'm trying to do is to restore the correct aspect ratio by changing the resolution of the image.

The problem is that AutoGK doesn't give me a mechanism (that I can see) to specify an arbitrary resolution. I can specify a wdith, but it chooses the height (and maintains the aspect ratio I'm trying to change). I can specify a couple of different possible aspect ratios via the .aspect file, but that gives me only a handful of options, none of which is the correct ratio for my source.

Edited:

This link should show what I'm trying to do. The shot on the left is the source resolution. The one on the right is the resolution I want to specify in the rip. Cropping is the same, but the aspect ratio is different:

http://img90.imageshack.us/img90/5144/resize8xp.jpg

This seems a fairly simple (though a bit unusual) thing to want to do. And yet AutoGK simply doesn't seem to give me a way to do it.

[CWR03]

The image on the left appears to be stretched, the right looks proper. Can you find something in the source that should be round which we could compare instead?

You can load the same file into Gordian Knot, as I previously suggested, which rarely gives an aspect problem. There you can confirm whether or not the aspect is wrong. If nothing else, you can force the resolution you like and encode it with Gordian Knot (AutoGK doesn't allow for adjustment of height beyond the preset aspects listed).

[replayed]

The image on the left appears to be stretched, the right looks proper.
Yes, that's what I've been saying. The image on the left is the source. The one on the right is my manual resize of it. (And believe it or not, faces show this much more vividly than round objects. I suspect our cognitive processing is better at spotting a misproportioned human than a distorted circle).

(AutoGK doesn't allow for adjustment of height beyond the preset aspects listed).
And that's the answer to my question. Thank you.

(I might add that this is a shame. It's a simple enough thing to add, even via just the .aspect file and not the interface. In general, I think AutoGK would be perfect if it allowed us to pause the process in order to modify the AVS file before allowing the encoding phase to begin. That also seems a simple change which wouldn't make it less usable for newbies while making it even more usable for a few others. Just a thought.)

Anyway, GK still looks a little forbidding to me. I'll probably give StaxRip a try first. Thanks again.

[manono]

I might add that this is a shame.

No it's not. If it were possible to specify both the height as well as the width, you would have tons of rookies unknowingly messing up the AR of their videos. "But the DVD is 720x480, so I wanted a 720x480 XviD"". That sort of thing. Your problem is exceedingly rare and can easily be fixed using the much more fully featured GKnot or other ways. AutoGK is at its heart a program for people to make good quality AVIs without knowing anything, or without ever having done it before. And for lazy people. :)

If you allowed people to name the resolution, they'd come whining back here about how AutoGK messed up their movie.

In general, I think AutoGK would be perfect if it allowed us to pause the process in order to modify the AVS file before allowing the encoding phase to begin.

I disagree with that as well. There are some external programs that allow you to do just that. But it wasn't designed to have the flexibility of GKnot. That's what GKnot (or StaxRip, or AVI.Net) is for.

[replayed]

If it were possible to specify both the height as well as the width, you would have tons of rookies unknowingly messing up the AR of their videos. "But the DVD is 720x480, so I wanted a 720x480 XviD"". That sort of thing.
But doesn't that depend on the interface for this feature? For example, the .aspect file allows options other than those available from the hidden features dialogue. In fact, I didn't know about the 2:1 option until I searched this board. How would newbies ever realize that they could specify, say, arbitrary resolutions via the .aspect file?

But it wasn't designed to have the flexibility of GKnot.
I do appreciate that. And I suppose it's a matter of opinion, but that seems like throwing the baby out with the bathwater to me. Just because a tool makes something trivial for those who aren't experts, it doesn't mean that it shouldn't make life easier for experts as well. AutoGK figures out a lot of the tedious details that have to be specified in more advanced programs. Would it be so terrible for it to give a (well-hidden) mechanism to pros so they can take over when they think they can refine on AutoGK's work?

I realize this isn't the AutoGK philosophy, and I respect that. I was just voicing my wishes. I understand I have other options.

[BigDid]

...I think AutoGK would be perfect if it allowed us to pause the process in order to modify the AVS file before allowing the encoding phase to begin. ...
Hi,

It is possible with
1/ AGKTweaker will need input from user to continue or
2/ AGKPAL will continue after 30sec.

:search: or look here: http://forum.doom9.org/showthread.php?p=809747#post809747

Disclaimer: Chances to screw up are increasing in proportions :D

Did

[replayed]

It is possible with
1/ AGKTweaker will need input from user to continue or
2/ AGKPAL will continue after 30sec.

Perfect! :w00t:

That's exactly what I was hoping for! Thank you sooooo much.


Disclaimer: Chances to screw up are increasing in proportions :D
I'll take those chances gladly!

[BigDid]

Perfect! :w00t:

That's exactly what I was hoping for! Thank you sooooo much.


I'll take those chances gladly!
You are welcome :)

Did

[CWR03]

Just because a tool makes something trivial for those who aren't experts, it doesn't mean that it shouldn't make life easier for experts as well.
Experts don't use AutoGK. :)

There's really not much of a learning curve between AutoGK and the full Gordian Knot, and while the trickiest part of Gordian Knot is the adjustment of the codec itself, it's fairly easy to achieve better quality results than with AutoGK.

[SeeMoreDigital]

I'm trying to rip a TV broadcast that was aired in a slightly squeezed aspect ratio, with everyone looking skinnier than they should. This wasn't the standard 16:9 squeeze unfortunately, so it's not just a matter of setting a flag in the stream.

To put it in more precise terms, the rip is coming out by default at 640x368, but to my eyes, the correct resolution looks much closer to 640x340. I'm trying to figure out how to make the rip come out at that resolution.It's more than likely that the broadcast source was intended to be displayed at 16:9 (aka: 1.7777:1).

An MPEG-4 encode with a resolution of 640x368, offers a square pixel aspect ratio of 1.74:1. Like-wise an MPEG-4 encode with a resolution of 640x340, offers a square pixel aspect ratio of 1.88:1... Neither of which are close to the 1.77:1 source!

If you want to view your 640x368 encode at 1.77:1 you will need to add some "aspect ratio signalling" (ARS) to the MPEG-4 bit-stream!

In this particular instance you could simply "drag-and-drop" your 640x368 encode into MPEG4 Modifier" and select its 16:9 DAR option... and save the new encode ;)

Provided you have a suitable MPEG-4 direct-show decoder filter (which offers ARS detection) installed, your software player will be able to display the new encode at 1.77:1.... The same goes if you have a suitably equipped stand-alone player!


Cheers

[replayed]

It's more than likely that the broadcast source was intended to be displayed at 16:9 (aka: 1.7777:1).
Thank you for your post.

However, this happens to be an unusual case when the broadcast was indeed screwed up. If you read my second post and follow the image link, you'll see that the broadcast ratio was plainly incorrect and reshaping it to 16:9 would still leave it distorted.

As I said in my first post, this was not simply a matter of flipping on or off the 16:9 flag. Thanks for the suggestion anyway.

Once again, thanks to BigDid's invaluable help, I was able to do exactly what I wanted. And in the process I discovered that there were others out there who agreed with me that AutoGK could be enhanced by allowing more advanced users to tweak its AVS settings. Enough others that no fewer than two utilities have been written to achieve this over the years.

I understand the point of view that AutoGK is perfectly designed for what it's trying to do. But I'm glad to know that there are others out there who agree with me that it could be in fact be improved upon. And who went out and did just that.

[SeeMoreDigital]

However, this happens to be an unusual case when the broadcast was indeed screwed up. If you read my second post and follow the image link, you'll see that the broadcast ratio was plainly incorrect and reshaping it to 16:9 would still leave it distorted..As far as I can see, your link does not provide an image from your "captured source" Only your perception of what you presume the source should look like!

As a matter of interest, how did you capture it and to what format. And can we see an uncorrected still frame from it please?


Cheers

[replayed]

As a matter of interest, how did you capture it and to what format. And can we see an uncorrected still frame from it please?
Fair enough.

The food chain looks like this:

Dig Cable Coax -> Cable Box -> ReplayTV DVR

Once recorded on ReplayTV, the Mpeg2 file was transferred over the network to my PC using DVArchive.

If I open the MPEG with Womble Mpeg Video Wizard (my editing tool of choice), I can grab the following interlaced frame:

http://img526.imageshack.us/img526/4324/testcap015xh.jpg

The "source" frame I used in my second post above was obtained after converting this Mpeg2 file to XviD using AutoGK, with default aspect ratio settings. The inverse telecine, cropping (and ususal 720x480 to 640x480 compensation) was done by AutoGK. The "target" frame was created by me by resizing the "source" JPEG using Irfanview.

BTW, if I watch the Mpeg recording on my DVR, the image is in fact distorted, whether or not my 4:3 TV is in 16:9 mode.

Do you now agree the source was fucked?

[SeeMoreDigital]

Thanks....

With regard to your provided image: -

http://img526.imageshack.us/img526/4324/testcap015xh.jpg

My first impressions are... Are you sure you've set-up everything correctly to generate your captures?

I have to say I've never seen a capture with the image pushed so far over to one side (ie: the left).... I think some of the original "image" may have been lost :eek:

[replayed]

Are you sure you've set-up everything correctly to generate your captures?
Yes, I'm quite sure. I've been doing this for years. I trust you'll agree that the title of this same movie looks centered here:

http://img521.imageshack.us/img521/1586/testcap027zf.jpg

Here are a couple of other title shots with the same set-up:

http://img119.imageshack.us/img119/558/testcap037ug.jpg

and

http://img218.imageshack.us/img218/5651/testcap041cq.jpg

You still think stuff is getting cut off?

[SeeMoreDigital]

After a trip over to the Sundance web site, I found a (poor quality) trailer of "Police Beat".

While playing it I found a few frames from the same scene as your originally posted image, ie: this one: -

http://img526.imageshack.us/img526/4324/testcap015xh.jpg


If I take a frame grab from the trailer I found, it looks like this: -

http://img100.imageshack.us/img100/609/829x3607pp.jpg


As you can see, the backgrounds are identical and when you compare the two it becomes apparent that your broadcast source had a fair bit chopped off the left and right, ie: like this: -

http://img117.imageshack.us/img117/6839/2019to.jpg


Anyway, long story short. It would seem your cropped source should be viewed at around 2.10:1, ie: like this: -

http://img46.imageshack.us/img46/1623/750x3605fk.jpg


Cheers

[replayed]

it becomes apparent that your broadcast source had a fair bit chopped off the left and right
The broadcast was chopped off, not my cap of it, which is what you were asserting.

And yes, I already knew that the broadcast was chopped off because it's on record that the premiere of the movie at the Sundance film festival was at 2.35:1.

And, as I've been saying all along, not only was the broadcast chopped off, it was also squeezed. That's what I meant by screwed up.

Anyway, long story short. It would seem your cropped source should be viewed at around 2.10:1
It's not a given that trailer hasn't been tempered with in some way, given that the celluloid print is supposed to be close to 2.35:1. Just eyeballing it, I decided that 2:1 looked the best to me. Anything wider and people's heads started to look squashed to me.