For anyone who is interested, this article pretty much explains face detection algorithms in cameras today. Incidentally, mine was one of the first cameras to have it (mid-2006), so it's not surprising that newer ones can detect profile (or partial profiles), whereas mine can't.
www.photoreview.com.au/tips/Insider-How-...amera-Face-Detection
Some highlights:
<ul><li>As its name implies, face detection is all about finding faces in a scene - and that involves shape recognition. </li><li> Identifying regions in the subject that contain skin color, using a skin filter which detects colour and texture. </li><li>Scanning these areas for patterns that could represent eyes and eyebrows, nostrils, and mouth. </li><li>In the early days of the technology, the algorithms used for the analysis could only detect faces looking directly at the camera. (like mine) </li><li>The latest algorithms can also detect faces in semi-profile. This requires the use of a larger number of detection points and much more processing capability </li></ul>
System Failures:
<ul><li>Inability to identify pets (and other animals). Face detection systems have been programmed to recognise human faces only. </li><li>They will not focus on cat, dog, horse or other animal faces. </li><li>Unwanted detection of faces in works of art. Most face detection systems will automatically focus on faces in paintings and photographs as well as statues. </li><li>Distance-based failures. Face detection systems will not identify faces that are too close to the camera - or too far away </li><li>Because they rely on pattern recognition, they can only identify an entire face so, if the camera 'sees' only one eye and part of the subject's nose, detection could fail. </li><li>Sunglasses, swimming goggles and other things that cover the eyes can cause face detection systems to fail. </li><li>False detections. These are becoming less common as algorithms are refined. However, there are situations where the face detection system will incorrectly identify patterns on walls, fabrics or similarly-complex subjects as faces. (computer pareidolia? - modern) </li></ul>
Conclusions:
<ul><li>I need a new camera for Christmas. One that is state of the art.</li><li>The failures may be as interesting as the successes, since that's what we're talking about here. </li><li>Since skin color is a major feature, it may totally rule out most known pareidolia (modern or ressler). That seems to be the case based on a quick review of available images. </li></ul>
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