Multispectral Image Out-of-Focus Deblurring Using Interchannel Correlation

Abstract

Out-of-focus blur occurs frequently in multispectral imaging systems when the camera is well focused at a specific (reference) imaging channel. As the effective focal lengths of the lens are wavelength dependent, the blurriness levels of the images at individual channels are different. This paper proposes a multispectral image deblurring framework to restore out-of-focus spectral images based on the characteristic of interchannel correlation (ICC). The ICC is investigated based on the fact that a high-dimensional color spectrum can be linearly approximated using rather a few number of intrinsic spectra. In the method, the spectral images are classified into an out-of-focus set and a well-focused set via blurriness computation. For each out-of-focus image, a guiding image is derived from the well-focused spectral images and is used as the image prior in the deblurring framework. The out-of-focus blur is modeled as a Gaussian point spread function, which is further employed as the blur kernel prior. The regularization parameters in the image deblurring framework are determined using generalized cross validation, and thus the proposed method does not need any parameter tuning. The experimental results validate that the method performs well on multispectral image deblurring and outperforms the state of the arts.

Spectral bidirectional texture function reconstruction by fusing multiple-color and spectral images

“…When capturing BTFs, the camera arc keeps fixed, while the light arc and sample table are sequentially rotated to predefined positions. The multispectral imaging system comprises a monochrome camera, a filter wheel, and an integrating sphere [31,32]. The sample is placed in the integrating sphere.…”

Normalized Total Gradient: A New Measure for Multispectral Image Registration

“…To deal with this problem, an autofocus method [5] has been proposed to compute the focus positions of lens using a focusing device (step motor). Alternatively, when the channel images are well aligned, the blur can also be computationally removed by multispectral image deblurring [4]. In this work, we will show in Section VII that multispectral images can be restored based on the proposed registration framework and the deblurring method introduced in [4].…”

“…Alternatively, when the channel images are well aligned, the blur can also be computationally removed by multispectral image deblurring [4]. In this work, we will show in Section VII that multispectral images can be restored based on the proposed registration framework and the deblurring method introduced in [4]. In this way, neither the calibration board nor the focusing device is further needed in the multispectral imaging systems.…”

Star Image Prediction and Restoration under Dynamic Conditions

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