8 votes
Accepted

Image rotation using FFT

Fourier transforms wouldn't help you with a rotation. You'd just end up having to rotate the matrix of Fourier coefficients, instead of rotating the original image. Consider for example an image made ...
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  • 23.7k
7 votes

Is there a image-format that support an array per pixel?

OpenEXR might be a good fit. You can have an arbitrary number of channels per pixel and the data types for each channel can be integers. http://www.openexr.com/
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4 votes

Image rotation using FFT

Yes, it is possible. Remember that a shift in space is equivalent to a linear-phase multiplication in frequency. A rotation can be accomplished by a shearing operation in one direction followed by a ...
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4 votes

Image rotation algorithm

It speed does not matter, I suggest to use a truncated sinc or a Lanczos isotropic kernel: to compute a target pixel, you back-rotate the filter and convolve it with the image. Since it is isotropic, ...
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2 votes

Is there a image-format that support an array per pixel?

Probably .dds. You can store there textures array or 3d texture both can be use as array per pixel. You can try creating this textures with ...
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  • 556
2 votes
Accepted

Wrong color in .ppm file

The issue is that on your system, writing out "\n" is writing out 0x0D0A, whereas on my system, it's only writing out 0x0A. If you explicitly write out 0x0A instead of "\n" I think it will work for ...
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  • 3,331
2 votes
Accepted

Image saved as DDS with 16f format in photoshop has strange FOURCC text

The tool seems to be generating an unofficial extended version of DDS in which the FOURCC code is replaced by a value from the D3DFORMAT enum. The code ...
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2 votes
Accepted

How to use maximum resolution (pixel density) with OpenGL in MS Windows

You might need to use a setting to tell Windows that your program is DPI-aware, meaning that it can adjust to very high-resolution screens like many current-gen laptops have. Lots of older programs ...
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2 votes
Accepted

Screen Space anti aliasing?

The easiest way to deal with this would be to provide thickness for the edges in the continuous setting. That is, make your edges out of solid capsules/cylinders, then you would not have this issue. ...
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  • 1,837
1 vote

Is it possible to convert Polar to Cartesian coordinates and map result to an image using opengl?

You'd be doing a change of coordinates from polar to Cartesian; at output point $(x,y)$ draw polar coordinate $(\theta = 2 \pi x, r = y)$. The coordinates in a unit circle drawn in the input image are ...
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  • 836
1 vote

How to calculate spatial frequency of an image just in one direction?

You can take a 1D Fourier transform of a row of pixels from the image; it will give you the horizontal frequencies present in that row. You could sample one row out of the image, or else average all ...
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  • 23.7k
1 vote

How to generate the stereographic projection of a 3D model

If instead of stereographic projection you can use other conformal projection. I would recommend you the "Least Squares Conformal Maps" algorithm. There are several implementations out there, ...
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1 vote

How is Raster and Random Scan Display different?

A raster display draws every pixel on the screen in every frame whether there is something to show or not. A random scan display activates only those pixel which are occupied by an geometric ...
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  • 1,750
1 vote
Accepted

Draw angles lines in raster graphics using bresenham line algorithm

The endpoint of the line doesn't extend out to the edge of the box because you're using the circle equation with a fixed radius: ...
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