Virtual dub avi's look elongated/squashed

[bones]

Hi all. I'm in need of some advice. . This

I'm still getting problems with 'elongated images' where the planet looks a bit squashed. Last time it was saturn in April. I've checked out and fixed up the collimation, checked sag in the imaging train, etc. I haven't been able to rectify this since and now that I'm attempting Jupiter, I'm still getting the same problem.

Looking at my AVI's that I capture from the IC Capture software, the planet seems to be a good shape, but when I go to import it into Virtual Dub it is here that the image then appears 'elongated' or 'squashed' in the preview screen before I even start the conversion to the bitmap file. After V Dub has converted it I've then got a video with a 'squashed planet'. I'd like to think its as easy as a setting in Virtual dub I can change. Any suggestions on how I can fix it up in V.Dub? (I'm using Virtual Dub version 1.9.11)

Tony

[Poita (Peter)]

Virtualdub displays images with square pixels, your camera may not be using square pixels, so the aspect ratio will look off.
Which camera is it?

[bones]

I'm using the Imaging Source DMK21AU.

[bones]

I'm hoping I've solved the problem, but the skies getting cloudy and its getting late so I won't be able to test it out till conditions improve again over the next days, weeks, ???
For those who may be interested ... I've been racking my brains on this one a bit. I noticed some avi's I took of Jupiter late last year were ok when I opened them up in virtualdub today so I reckoned the problem is not with virtual dub. With this in mind I checked the IC Capture settings for the camera and went back and read over all the info that Mike (Iceman) posted on IIS re capturing and processing (thank Mike - much appreciated useful information) and noticed that I may have had the wrong codec selected on the camera. I've now changed it to the Y800 codec (I have no idea how this changed as I know I had this selected before - it possibly changed when I had trouble with the drivers in March this year and downloaded and installed updated drivers and IC capture software but didn't set it up right? Come to think of it my processing has been flattened / skewed since then. Looking at the user guide for the IC Capture settings I noticed the codec I had was maybe compressing the file on capture which may have resulted in the squashing of the image vertically when brought into virtualdub as an uncompressed image? My understanding is that the y800 codec is an uncompressed format so hopefully the x-y compression wont change now with future runs when I try again? I'm not an expert on this stuff and time will tell if i'm right. Thoughts from anyone in the know on this stuff would be appreciated.
Tony

[DavidLJ (David)]

Tony. Can't help directly but this may be of some indirect help. I always get squashed images from my GstarEx video camera. It's not the camera's fault though. The camera outputs a 768 x 576 frame but the capture device in my laptop only generates a 720 x 576 frame. At first, in my ignorance, I assumed that I was losing some of the camera's output - 48 pixels from each line (i.e. 768 – 720). But it turned out that that was not the case. The full image width of 768 pixels was being recorded by the capture device but it was crammed into only 720 pixels. The result is that each frame is compressed horizontally (or, if you like, stretched vertically). My solution is to stack the avi frames normally and then resize the resulting stacked image from 720 x 576 back up to 768 x 576. This removes the distortion. Maybe your problem has a similar cause?