Arun Krishnan

Panoramic image acquisition

This paper is concerned with acquiring panoramic focused images using a small field of view video camera. When scene points are distributed over a range of distances from the sensor, obtaining a focused composite image involves focus computations and mechanically changing some sensor parameters (translation of sensor plane, panning of camera etc.) which can be time intensive. In this paper we present methods to optimize the image acquisition strategy in order to reduce redundancy. We show that panning a camera about a point f (focal length) in front of the camera eliminates redundancy. The non-frontal imaging camera (NICAM) with tilted sensor plane has been previously introduced as a sensor that can acquire focused panoramic images. In this paper we also describe strategies for optimal selection of panning angle increments and sensor plane tilt for NICAM. Experimental results are presented for panoramic image acquisition using a regular camera as well as using NICAM.

Use of a nonfrontal camera for extended depth of field in wide scenes

This paper describes a method for obtaining a composite focused image from a monocular image sequence. The image sequence is obtained using a novel non-frontal camera that has sensor elements at different distances from the lens. This paper first describes the motivation behind the non-frontal camera, followed by the description of an algorithm to obtain a focused image of a large scene. Large scenes are scenes that are deep and wide (panoramic). Consequently, the camera has to be panned in order to image all objects/surfaces of interest. The described algorithm integrates panning and generation of focused images. Results of experiments to generate extended depth of field images of wide scenes are also shown.