COPS: How to rotate and keep all the image?

   3464   2   1
User Avatar
Member
7046 posts
Joined: July 2005
Offline
Hello,
Perhaps I'm missing something, but is there an easy way to rotate an image and keep the whole image? If I have a 800x600 image and I rotate it 90 (Xform COP), I end up with the top and bottom chopped off… I then have to put a Crop on and tediously get the rest of the image back.

Cheers,

Peter B
Cheers,

Peter Bowmar
____________
Houdini 20.5.262 Win 10 Py 3.11
User Avatar
Member
4140 posts
Joined: July 2005
Offline
Well, the Window COP is a little more elegant internally and probably with regard to image quality, but in the end it's not a lot less work that the Crop COP. Might seem a little less messy if you apply the Window before the transform. I get the sense it's *supposed* to be the way to do it, but there needs to be a little bit more automated sense about it - so that the sort of straight up operation you're describing doesn't require doing math for offsets. Of course, this is a great example of a cry for an OTL, but yup it should be easier in the original package IMHO.

You'll need Large Canvas turned on in the Comp Project for this to work, I suspect.

Oh, and btw, I assume you realize that with canvas turned on, you don't need to worry about any of this, really, because all the image is still there for the pipeline. I assume you wanted the resolution setup for you automatically for readability or convenience down the line.

Cheers,

J.C.
John Coldrick
User Avatar
Staff
5285 posts
Joined: July 2005
Offline
If you're just doing 90' rotations, you can use the Flip COP, with ‘Flop Image 90 degress" on. If you are doing other rotations, you can’t do this obviously.

A crop of:

H: -0.43 1.43
V: -0.43 1.43

in UV units will always keep all the rotated data, as long as you don't scale.

I was considering adding an option to the Crop COP to ‘Expand to full Canvas’, but as the canvas can get extremely large (even a scale of 10 on a 640x480 image with no previous canvas makes one of 6400x4800), I considered this a risky feature.
  • Quick Links