iOS Face Detection Issue

Question

I am trying to use CoreImage\'s face detection in iOS 5 but it is not detecting anything. I am trying to detect faces in an image that was just captured by the camera using thi

Answer 1

I can't reply to your @14:52 comment directly Vic320, but I've been playing with the front camera for face detection - I went round and round in circles since I couldn't get the front camera to pick up my face at all...

Turns out it's very sensitive to rotation - I noticed that when holding my iPad2 in portrait (as you'd expect while using the front camera) I was getting less than 10% recognition accuracy. On a whim, turned it sideways and was getting 100% recognition with the front camera.

Simple fix for this if you're using the front camera always in portrait is to add this little snippet:

NSDictionary* imageOptions = [NSDictionary dictionaryWithObject:[NSNumber numberWithInt:6] forKey:CIDetectorImageOrientation];
NSArray* features = [detector featuresInImage:image options:imageOptions];

That 6 in there forces the detector to operate in portrait mode. Apple's SquareCam Sample has a whole bunch of utility methods to figure out what orientation you're in if you need it to dynamically figure out your orientation.