When Google released their Camera app on Google Play earlier today for users who have Android 4.4, one of the new features noted was something called Lens Blur. This is a new mode Google has introduced that enables a software based shallow depth of field. One of the main uses of a shallow depth of field is to create a bokeh effect where the primary subject of a photo is in focus while the background is blurred. HTC recently enabled this in their new HTC One (M8) through hardware consisting of a dual camera system. Google's new Camera app achieves this entirely with software.
A shallow depth of field has historically been confined to single lens reflex (SLR) cameras with their large lenses and apertures. To get similar results, Google uses a combination of images to capture a scene. The images, after being passed through various algorithms, are used to generate a 3D model of the scene. With estimates of the distance to every point in the scene, users can simply tap on an image to set that as the primary focal point. The camera app can then calculate distance from the selected focal point for everything else in the scene and adjust focus accordingly.
As noted earlier, HTC added a second camera to their latest flagship device to help capture all of this data so their camera app can produce bokeh effects. Google captures their data by having users move the camera in an upward motion to get the necessary images.
Let us know if you are looking forward to utilizing bokeh effects on your images.
source: Google Research Blog
