Spherical - to - Cubic ???

Q&A about the latest release Version
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rohan
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Joined: Sun Jun 17, 2007 2:07 am

Is spherical just the same as "equirectangular" ?

I don't see the option to use a spherical impust in Pano2QTVR.

When I try to feed it a spherical image as equirectangular and convert to cubic, it kind of gives me distorted poles - it looks like it pulls inwards too much of the image, and squeezes it.
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360Texas
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An equirectangle image dimensions are like 1000 pixels high x 2000 pixels wide. It is the image output dimensions that you specified in the stitching software.

Pano2qtvr then converts this equirectangle image to be display or rendered in QTVR or Flash. QTVR is a web browser plugin or viewer that then displays the image in a spherical view. It projects the image [texture] on the inside of a sphere like the inside surface of a soccer ball.

Your equirectangle image may be cubed or sliced into 6 cube faces or tiles. Then each tile is essentially 'flattened' to remove the fisheye lens distortion.. some people call this 'defished' or 'dewarped'.

If you cubed a non equirectangle image [ 2000 x 8000] you might get different cubed face distortions like you are referring to.
Dave
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rohan
Posts: 2
Joined: Sun Jun 17, 2007 2:07 am

Suppose I have a basic JPEG - like something that would directly be played back in PTViewer. One rectangular JPEG, that even viewed in paint looks like a continuous panorama, no division, no cubes, just one wide image meant to be played back as a cylindrical projected VR.

Do I tell pano2qtvr that it's equirectangular?
panocanarias
Posts: 28
Joined: Sat Sep 09, 2006 7:28 pm

Rohan:
Is spherical just the same as "equirectangular" ?
Yes! As Dave mentioned before, an equirectangular pano always has an 2:1 ratio (2000px wide:1000px high; 5000:2500.....)
I don't see the option to use a spherical impust in Pano2QTVR.
You choose Projekt (pano) type at the "Projekt-TAB", equirectangular (2:1 ratio), Cubic (6 cubes- 1:1 ratio), or Cylindrical (free ratio).
I have a basic JPEG - .... One rectangular JPEG, ..... as a cylindrical projected VR.
Do I tell pano2qtvr that it's equirectangular?
NO, a cylindrical pano is NOT an equirectangular pano !
You should read again, what Dave wrote above!
To understand types of panoramic images you may read this:
http://www.panoguide.com/howto/panoramas/types.jsp

Hope, it helps
Regards, Klaus
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