Re: using a pixel shader for undistorting an image?

Giff,

Sounds like you already got the difficult part out of the way:
calibration. How did you get the mappings between distorted and
corrected image-pixels? This is what you plan to use as a lookup table
on the GPU right?

I wonder if just resampling a 640x480 image interactively when the
pixel transforms are given is too computationally intensive to move to
GPU. If it is a just-for-fun project, cool. But GPUs would be best at
handling large streams of data and apply the same operation on to a
bunch all at once. In this case, the only such operation I see is to
resample based on a lookup table. Sounds easy enough. I have come
across using lookup tables for interactive manipulation of optical
properties of primitives for volume rendering, and this one sounds
along the lines. Good luck!

P.



On Apr 12, 3:19 am, "Giff" <Giffn...@xxxxxxxxx> wrote:
On 12 Apr, 11:46, Harris <xgeorg...@xxxxxxxxxxxxx> wrote:



The problem you are describing is generally known as "camera calibration"

Not exactly, maybe I was not clear enough. I already did the
calibration, now I need to use the results of it to undistort the
images coming from the camera, I know how to do this in C++, what I
want to do is to move this computation onto the GPU, using a pixel
shader.

I think I have a clue on how to do this: in the initialization process
I will create a texture containing, for each pixe, the destination of
that pixel in the undistorted image (or probably just the offsets in
the x and y directions). I will then pass this texture to the pixel
shader and use it to sample the right pixel.

Thanks for your reply anyway.


.

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