Detection of bruised yellow peach using hyperspectral imaging combined with curvature-assisted Hough transform circle detection and improved Otsu

The quality of yellow peaches was severely reduced due to bruising. Detection of bruised areas in yellow peach is easily disturbed by the calyx and stem ends. Therefore, it is proposed to utilize hyperspectral imaging in conjunction with I-Otsu in the detection of bruise detection in yellow peach after distinguishing between calyx and stem end using curvature-assisted Hough transform circle detection. The band ratio was used to improve the contrast of the images, and the improved Otsu method was used to improve the segmentation accuracy. Noise in the image is eliminated by adaptive median filtering. The effects of the calyx and stem ends are eliminated by curvature-assisted Hough transform circle detection. Spectral bands with valid feature information were selected by principal component analysis and key single-wavelength images (452.8 nm, 608.9 nm, 671.8 nm, 689.4 nm, 825.7 nm, and 966.2 nm) were selected from the loading curves of the spectral regions to create PC images and band ratio images. Band ratio (Q608.9/689.4) images with I-Otsu were used to segment the bruise region. Ultimately, 96% of the bruised yellow peaches were correctly identified. This study demonstrates that hyperspectral imaging combined curvature-assisted Hough transform circle detection and I-Otsu can accurately identify bruised areas as well as calyx and stem ends in yellow peach.