Accurate stereo matching based on multiband imaging

Abstract

The accuracy of stereo matching depends on precise detection of corresponding points in a pair of stereo images by template matching. A multiband imaging system captures more than three channels in a visible range. The multiband imaging technique is useful for improving the accuracy of the stereo matching. This paper proposes an imaging system and an algorithm for stereo matching based on multiband images. The imaging system is composed of a liquid-crystal tunable filter and a high sensitive monochrome camera. This imaging system has the advantage that low contrast color textures that are lost in RGB images could be detected in the multiband-spectral images. We use a modified sequential similarity detection algorithm (SSDA) for the acceleration of multiband template matching. The similarity is calculated for each band in the descending order of the variance in template. The template matching is accelerated by quick discontinuance of the calculation at dissimilar points. Experimental results show that multiband stereo matching is accurate in comparing with RGB stereo matching. Measurement targets were sheets of color texture patches with small color differences. The rate of detection of correct corresponding points was 98.4% by multiband stereo matching, while the rate was 34.7% by RGB stereo matching. Moreover, use of the modified SSDA reduced the CPU time.