How to convert omnidirectional/ 360 degree image into rectangular form?

I wanted to convert 360 image into rectangular form. My image is like this type

Answer 1

[Image Analyst]

What I'd do is to find the inner and outer radii. Lots of ways to do that but you can just take a guess if you want. Then convert those into xInner and yInner and xOuter and yOuter using sin() and cos().

numAngles = 2 * pi * outerRadius;
angles = linspace(0, 2*pi, numAngles);
xOuter = outerRadius * cos(angles);
yOuter = outerRadius * sin(angles);

Then I'd go down the xouter arrays using improfile() to get the intensity along each ray. Then put that into a column of your output matrix. Not hard - give it a try.

for k = 1 : length(xOuter)
    x2 = xOuter(k);
    y2 = yOuter(k);
    x1 = rows/2;
    y1 = columns/2;
    p = improfile(x1,y1,x2,y2)
    outputImage(k, :, :) = p;
end

That won't work as is and that's intentional - I've left the fun parts for you because I assume you want to solve this puzzle yourself to have some pride of ownership. See if you can get it to work. It's really not hard.

[Image Analyst]

You can also use pol2cart() and meshgrid() like someone will undoubtedly suggest, but there's problems with that method, as you'd find out if you tried it.