Image capturing device and digital zooming method thereof

Abstract

An image capturing device and a digital zooming method thereof are proposed in the invention. The method includes the following steps. A scene is captured by a primary lens and a secondary lens to generate a primary image and a secondary image. Image rectification is then performed on the primary and the secondary images to obtain two corresponding rectified images. Feature points detected and matched from the two rectified images are used to determine a corresponding overlapping region, respectively. Pixel displacement and depth map in the two overlapping regions could be calculated and estimated. Image zooming and warping techniques are performed on the two rectified images to obtain corresponding warped images using a recalculated homography matrix according to each specific zooming factor. Finally, the two overlapping regions in the warped image are fused by a weighted blending approach to generate a digital zoomed image.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the priority benefit of Taiwan application serial no. 103139384, filed on Nov. 13, 2014. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The invention generally relates to an image capturing device and a digital zooming method thereof, in particular, to an image capturing device with dual lenses and a digital zooming method thereof.[0004]2. Description of Related Art[0005]With development in technology, various smart image capturing devices, such as tablet computers, personal digital assistants and smart phones, have become indispensable tools for people nowadays. Camera lenses equipped in high-end smart image capturing devices provide same or better specifications than those of traditional consumer cameras, and some even provide three-dimensional image capturing fea...

AI Technical Summary

Benefits of technology

[0024]In summary, in the image capturing device and the digital zooming method proposed in the invention, by analyzing different imaging properties and distortion levels of the dual lenses, image zooming and image warping are automatically performed on images captured by the dual lenses according to a zooming factor to generate two warped images with similar focal lengths, sizes, and fields of view. The two warped images are fused by their weighted sum, and a digital zoomed image corresponding to the zooming factor would be obtained thereafter. As compared with the existing digital zooming techniques, the image capturing device and the digital zooming method proposed in the invention may provide a digital zoomed image with high quality throughout a digital zooming process.

Problems solved by technology

When such image capturing devices perform digital zoom to enlarge an image, image blur and distortion may occur.

However, after the image is enlarged, it details may not be preserved.

However, throughout the digital zooming process, if the target image needs to be switched to the other image, the viewed image may appear flickering or unsmooth.

Accordingly, to present an image that meets the user's expectation during an image digital process is one of the problems to be solved.

Images