Continuous electronic zoom for an imaging system with multiple imaging devices having different fixed fov

Abstract

A method for continuous electronic zoom in a computerized image acquisition system, the system having a wide image acquisition device and a tele image acquisition device having a tele image sensor array coupled with a tele lens having a narrow FOV, and a tele electronic zoom. The method includes providing a user of the image acquisition device with a zoom selecting control, thereby obtaining a requested zoom, selecting one of the image acquisition devices based on the requested zoom and acquiring an image frame, thereby obtaining an acquired image frame, and performing digitally zoom on the acquired image frame, thereby obtaining an acquired image frame with the requested zoom. The alignment between the wide image sensor array and the tele image sensor array is computed, to facilitate continuous electronic zoom with uninterrupted imaging, when switching back and forth between the wide image sensor array and the tele image sensor array.

Description

RELATED APPLICATION[0001]The present application claims the benefit of U.S. provisional application 61 / 167,226 filed on Apr. 7, 2009, the disclosure of which is incorporated herein by reference.FIELD OF THE INVENTION[0002]The present invention relates to an electronic zoom for imaging systems, and more particularly, the present invention relates to a continuous electronic zoom for an image acquisition system, the system including multiple imaging devices having different fixed FOV.BACKGROUND OF THE INVENTION AND PRIOR ART[0003]Digital zoom is a method of narrowing the apparent angle of view of a digital still or video image. Electronic zoom is accomplished by cropping an image down to a centered area of the image with the same aspect ratio as the original, and usually also interpolating the result back up to the pixel dimensions of the original. It is accomplished electronically, without any adjustment of the camera's optics, and no optical resolution is gained in the process. Typic...

AI Technical Summary

Benefits of technology

[0009]The present invention describes a continuous electronic zoom for an image acquisition system, having multiple imaging devices each with a different fixed field of view (FOV). Using two (or more) image sensors, having different fixed FOV, facilitates a light weight electronic zoom with a large lossless zooming range. For example, a first image sensor has a 60° angle of view and a second image sensor has a 60° angle of view. Therefore, Wide_FOV=Narrow_FOV*6. Hence, switching between the image sensors provide a lossless electronic zoom of 62=36. This lossless electronic zoom is also referred to herein, as the optimal zoom:Optimal_Zoom=(Wide_FOV / Narrow_FOV)2.

[0015]The method further includes the steps of providing a user of the image acquisition device with a zoom selecting control, thereby obtaining a requested zoom, selecting one of the image acquisition devices based on the requested zoom, acquiring an image frame with the selected image acquisition device, thereby obtaining an acquired image frame, and performing digitally zoom on the acquired image frame, thereby obtaining an acquired image frame with the requested zoom. The calibration of the alignment, between the first image sensor array and the second image sensor array, facilitates continuous electronic zoom with uninterrupted imaging, when switching back and forth between the first image sensor array and the second image sensor array. Preferably the electronic calibration is performed with sub-pixel accuracy.

Problems solved by technology

Typically some information is lost in the process.

Typically, a camera with a large dynamic zoom range requires heavy and expensive lenses, as well as complex design.

Images