face detection disappointing so far on tango couples (EDITED: not as bad as I thought)

This is just my first, naive try using the Haar cascades in OpenCV. I'm using one frontal training set & one profile.

It could be that if the kinect was closer, then it would get better results... but then of course, there would be more occlusion for the theoretical other dancers. I did enlarge the image in order to do the detection, but this didn't help enough. My problem might also be that the kinect is from an angle above, and so, the faces are not straight-on enough. Wonder if I could solve with rotations? Seems CPU-expensive. Le sighz.

Here are some shots of it half-way working. It is, very disappointingly, very abysmal. I'm wondering if I can tweak it into functionality, though. I did try a quick skin detection thing, and that did really well. I think I could even tinker with it and get rid of the false positives.

 The back of the head isn't bad, considering. It would work for my purposes... 

Close but no cigar

Just with the background subtraction [below].. I'm going to also use the depth to subtract the background when I get around to it... 

Checking out: http://blog.mashape.com/post/53379410412/list-of-50-face-detection-recognition-apis

http://www.semanticvisiontech.com/

http://chenlab.ece.cornell.edu/projects/FaceTracking/

http://pointclouds.org/blog/hrcs/aaldoma/index.php ??

I think I might go into the skin detection more... 

EDIT: So it turns out I forgot to draw the profile detections boxes... plus, the other kinect seemed to get a better view. It was mostly my face. I think I could do a mirror and get the other profile... can't do this for all angles though, and it doesn't catch my partner hardly at all.  This is still mostly open-embrace. Close embrace is going to be tricky.

EDIT #2: 

Ok, so actually the background subtraction was hurting more in this case than helping. I was skeptical, but... I think what I need to do is just put a bounding box around the couple, and detect the face in there -- would be faster.  Anyways, ya, so with the first kinect & only frontal face, the background helped A LOT (for the little positives that were created) but in this case, NOT having the background really helped. I mean, looking at the visuals, you can see where it would get confused, but it really was better in the other case. Anyways... I also fooled around with the brightness/contrast. I added the other side profile & I was actually detecting my partner a few times.

smaller face detections!

So, again I think this all has to be supplemented by skin detection. It will definitely fix the relatively few number of false negatives. However, it is still pretty iffy in close embrace...so I think think I need to find another way (in addition? instead?). Damn you close embrace!!! You keep on foiling me!! Also, I can do template matching for a while once I find the face. But I do need to have a robust way of finding face the first time. Again, I think I also could do a bounding box on the couple, and only search that image. Could do that from the depth image maybe? Plus, seeing where the skin color falls?

Brighter lighting would help but this is SUPPOSED to be for a tango milonga. Wonder if there is a way to make Kinect RGB part better in dim light?