Looking at some slides from the PS4 HSA Audio Presentation from AMD APU 13 I noticed that the processor used in the presentation is a Cadence/Tensilica DPU.
here is a link to Cadence website if you would like to read up on their DPU's
all about Games ,Motion Controllers , PlayStation Move, Xbox Kinect , Wii , Wii U, PlayStation Eye,PlayStation 4, PS4,PS3,Xbox 360,Xbox One & more.
Abstract "An obstacle detecting unit detects an obstacle for a user wearing a head mounted display from an image of the outside world. A distance calculating unit calculates the distance from a detected obstacle to the user wearing the head mounted display. An obstacle replacing unit replaces the detected obstacle with a virtual object. A virtual object synthesizing unit generates a virtual object at a position within a virtual space displayed on the head mounted display, in which the position is determined according to the distance to the obstacle."