Android camera: need to turn FLASH_MODE_TORCH on automatically

Question

My code must automatically turn on the flashlight LED when the light is insufficient.

I can turn the flashlight on in the torch mode:

camera = Camera.open();
final Parameters p = camera.getParameters();
// ...
p.setFlashMode(Parameters.FLASH_MODE_TORCH);
camera.setParameters(p);

But I must not turn it on when it is not needed.

How do I find out, programmatically, whether I need to turn the flashlight on?

In other words, how can my application know if there's enough light?

Answer 1

You can look at these two SO posts for checking, what light level is around you:
Lightsensor Value and Brightness of surrounding

But you have to decide, at which light level you'll turn the flashlight on.

Answer 2

If you wish have it turn on automatically while taking a photo if the light is insufficient, then FLASH_MODE_AUTO should do the trick for you