Friday, March 13, 2015

3D Photos - Playroom

In this post, I am gonna revisit Depth Map Automatic Generator 3 (DMAG3) which is a depth map generator based on the "graph cuts" technique. The stereo pair I am gonna use comes from the 2014 Stereo Dataset that originates from Middlebury.


Left image.


Right image.

The original stereo pair is 2800 pixels wide, which is way too wide for DMAG3. I reduced the width to 700 pixels. I estimated the minimum disparity to be 10 and the maximum disparity to be 80. It doesn't have to be exact. I used the 64 bit version of DMAG3 available at 3D Software.


Depth map obtained using window radius = 2, gamma proximity = 17, gamma color similarity = 14, lambda = 10, and K = 30.


Corresponding occlusion map.

These are the default parameters (as of today). Here, I want to increase the window radius to get better accuracy. On my machine, this caused DMAG3 to crash because it ran out of memory. I therefore switched to the 64 bit version. By the way, the occlusion map looks ok, therefore I won't have to play with parameter K.


Depth map obtained using window radius = 8, gamma proximity = 17, gamma color similarity = 14, lambda = 10, and K = 30.

I want to go back to the previous parameters and reduce the smoothness by lowering parameter lambda.


Depth map obtained using window radius = 2, gamma proximity = 17, gamma color similarity = 14, lambda = 5, and K = 30.

Finally, I am gonna increase the window radius (back to 8) keeping the lambda at 5.


Depth map obtained using window radius = 8, gamma proximity = 17, gamma color similarity = 14, lambda = 5, and K = 30.

I am gonna stop right here fiddling around with the parameters, as I don't think the depth map can be improved much (automatically). It does not hurt to smooth this last depth map with Edge Preserving Smoothing 5 (EPS5).


Depth map after edge preserving smoothing. Now, we are ready for the best part: generating an animated gif.


This is the wigglegram aka animated gif obtained by uploading the left image and the depth map (make sure you invert the colors prior) to depthy (a very excellent web site). Depthy even allows you to use a brush to fix up the depth map while checking the animation (a truly wonderful tool).