Friday, May 20, 2016

Depth Map Automatic Generator 5 (DMAG5) - Downsampling factor

As you probably know by now, Depth Map Automatic Generator 5 (DMAG5), the leading automatic depth map generator from ugosoft3d, has a new parameter which downsamples the input images in order for the whole process of generating depth maps to be (much) faster. Let's see the impact of this "downsampling factor" in the quality of the depth/disparity maps produced by DMAG5.


Input to DMAG5: set of two rectified images (dimension = 1920x1080)

Let's generate depth maps with DMAG5 using a downsampling ratio/factor of 1 (no downsampling), 2, and 4.


Depth/disparity map generated by DMAG5 using a downsampling ratio/factor of 1.

This takes 07:40 (7 minutes 40 seconds) of cpu time using debug version of DMAG5 on a linux box.


Depth/disparity map generated by DMAG5 using a downsampling ratio/factor of 2.

This takes 00:53 (53 seconds) of cpu time using debug version of DMAG5 on a linux box. This is a speedup of 8.7 when compared to cpu time without downsampling.


Depth/disparity map generated by DMAG5 using a downsampling ratio/factor of 4.

This takes 00:07 (7 seconds) of cpu time using debug version of DMAG5 on a linux box. This is a speedup of 65.7 when compared to cpu time without downsampling.

Of course, as the downsampling ratio/factor increases, the depth map quality decreases a bit but isn't a good speedup worth a little bit of depth map quality degradation? At the very least, it's a great to see the effects of the parameters on the generated depth/occlusion maps.


Animated gif created by wigglemaker using the depth map obtained with a downsampling factor equal to 2.