: How to convert a normal photo into an equirectangular image? I have a regular panorama image. How do I convert it into an equirectangular picture (normal -> equirectangular)? Most results I find

@Connie430

Your image have realy litle information and is too small. Also dont have a equirectangular geometry. But you can do it in Blender, its free. Just render it in "Panorama"> "equirectangular"> "Render.
To see HDRI images in 360 you can use this site: panoramaviewer.1bestlink.net/

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@Debbie163

You can not do that on your image as you have it.

1) You want a cylindrical projection on a sphere. First your canvas needs to be at one exact proportion. 3.1416:1 (Use any pixel sized canvas you want, for example 3141x1000px)



2) And you (normally) need the horizon to be at the center of the canvas.



On a cylindrical projection (from a sphere) you have a specific deformation on the projection due the vertical projected dimension versus the real height of that segment, so you need to compensate that when you draw your cartoon at a flat canvas.

An easy way to do this is using the Spherize filter in Photoshop. (On the arcaic version I have right now on this computer is on Filter >Distort > Spherize)

But you ONLY need to distort that on the vertical axis.



But besides that you need to define what portion of a 360 panorama you have. Imagine another chicken taking a photo. What would be the angle of the lens used?

I feel that it is a wide angle lens, lets thing you are taking like 120° angular field. This means you need to complete your image to the stuff you have behind the chicken photographer.





The Google VR aplication you want to use says that need a cylindrical projection, but asks for a proportion of 2:1 on your image. A 2:1 projection normally is a spherical one that has a diferent deformation, but it is harder to achive in a video for example.

For practical reasons they are in fact asking for cylindrical projections, so you simply resample your original 3.1416:1 to 2:1 as a final step.



Simply resample the final image. If your canvas was 3141x1000 px simply resample it to 2000x1000px. Do not crop it. The chicken will look slimmer but will go faty again on the VR aplication.



For your initial canvas:
On your specific image it is hard to tell the angle of view, but let us see 3 scenarios.

(A) Your field of view is arround 120° so you can acomodate 3 photos of the cute pets as your posted image is 2048 the canvas needs to be 2048x3=6144px and now divide that with pi = 1955px

6144x1955px

(B) But if you do not want the pets to be too small let us asume the photo covers 180° = 2048x2=4096 / pi=1303

4096x1303px

(C) Or play with the numbers.

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