[how to] capture pictures from ALL 3 cameras (in RGB, yes)
If you want to experiment with your HTC One (M8) and want to know about the "secret" second rear camera, then this thread is for you. Works with M8 ONLY!
HTC told the press and the htcdev-members (after releasing the SDK) recently that the second lens of the "duo camera" would be something like a depth sensor. It turns out that this is definitely not the case. It is just a simple RGB-cam with 1080p resolution.
I read about the functionality and concept behind the camera on the following page (German only):
Concept of HTC One M8's Duo-Camera
On the page there is a sample App called DuoCamTest. It needs a rooted M8, APK and source can be downloaded.
The guys there used an internal debug-interface located at /system/bin/camera_test
to take two pictures at the same time. One with full resolution (4 MP) and one with 2 MP (Full HD) using the second rear camera. On a rooted device you can play around with it.
I discovered a way to identify all the three camera-modules. Don't know, if somebody did this before, sorry:
OK, that was easy.