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Cheng-Long Chuang Cheng-Shiou Ouyang Ta-Te LinMan-Miao Yang En-Cheng YangTze-Wei Huang Chia-Feng KueiAngela Luke Joe-Air Jiang 《Computers and Electronics in Agriculture》2011,77(1):41-59
This paper presents a new automatic and effective quarantine system for detecting pest infestation sites in agricultural products, e.g. fruits. This work integrated mechanical design, mechatronics instrumentation, X-ray and charge-coupled device (CCD) image acquisition devices, LabVIEW-based analysis and control software, and image diagnosis algorithms into the automatic X-ray quarantine scanner system. Based on the LabVIEW development platform, a friendly graphical user interface (GUI) was designed for assisting the operations of quarantine scanner system. To enhance the accuracy and efficiency of pest quarantine process, a control scheme for performing start-up procedure of the system, parameter setting and calibration of the X-ray source and line-scan sensor, and automatic inspection for pest were developed. A novel pest infestation detector consisted of image processing algorithms were also proposed to aid the operator in identifying possibly infested fruits. The image processing procedures include contrast enhancement, median filtering, mathematical morphology operators, and adaptive thresholding by statistical z-test for identifying the infested sites of fruit on an X-ray image. Experimental results show that the X-ray quarantine scanner and pest infestation detector are able to locate the infested sites with highly successful rate up to 94% on the 4th day after eggs implanted. Furthermore, both intact and egg-implanted fruits were used to evaluate the sensitivity, specificity, accuracy, and precision of the proposed system. The evaluation results are respectively 96.8%, 98.6%, 97.7%, and 98.7%, which are significantly better than traditional visual inspection. 相似文献
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对比RGB(红,绿,蓝)颜色空间下各颜色分量间多种色差运算的自适应阈值分割与基于H(色调)和S(饱和度)的K均值聚类算法对苹果影像的分割,选取适宜于自然生长状态下成熟期苹果影像分割的最佳算法分割目标物.在影像分割的基础之上,通过计算影像中苹果区域的总面积与单果平均面积之商确定苹果数目.试验结果表明:1.1×R-G色差运算结合自适应阈值分割算法对成熟期苹果影像有较好的分割效果;以影像中苹果总面积与单果平均面积之商确定苹果数目的算法准确率可达82.18%,计数方法准确率高. 相似文献
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[目的]优化薏米视觉检测中图像采集条件。[方法]在薏米视觉检测中通过图像采集设备采集薏米图像,以灰色、黑色、红色背景,在0～80 lx的光强区间,对采集后的图像进行阈值分割,采用阈值分割算法对图像进行处理。以分割图像薏米粒误差率为评价标准,分析了背景颜色、光照强度2个因素对薏米图像的影响,以确定薏米视觉检测中图像采集的最佳环境。[结果]较好的图像采集环境是黑色背景下50～60 lx的光照强度,其误差控制在6%,且在该光照区间旁光照强度上下浮动10 lx内误差也在10%内,这种环境能有效提高薏米图像的质量。[结论]优化薏米图像采集环境可大幅度降低图像噪声的影响,提高了薏米图像的质量。 相似文献
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几种图象分割算法在棉铃虫图象处理中的应用 总被引：17，自引：1，他引：17
本文介绍了6种图象分割算法在棉铃虫图象分割中的应用。结果表明，平均值分割算法和迭代阈值分割算法能够获得较好的分割结果，其中迭代法分割结果较符合实际需要。而P－参数法虽最终能获得较好的分割结果，但需要人为干预阈值的选择过程；Johannsen方法能够正确分割出棉铃虫区域，但无法反映棉铃虫的斑纹特征；而Kapur法和Yager方法则将棉铃虫区域的很多内容分割为背景区域，难以反映出棉铃虫实际特征，本研究为进行昆虫图象的特征提取、特征测量及种类自动识别研究奠定了基础。 相似文献
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Machine vision for counting fruit on mango tree canopies 总被引：1，自引：0，他引：1
W. S. Qureshi A. Payne K. B. Walsh R. Linker O. Cohen M. N. Dailey 《Precision Agriculture》2017,18(2):224-244
Machine vision technologies hold the promise of enabling rapid and accurate fruit crop yield predictions in the field. The key to fulfilling this promise is accurate segmentation and detection of fruit in images of tree canopies. This paper proposes two new methods for automated counting of fruit in images of mango tree canopies, one using texture-based dense segmentation and one using shape-based fruit detection, and compares the use of these methods relative to existing techniques:—(i) a method based on K-nearest neighbour pixel classification and contour segmentation, and (ii) a method based on super-pixel over-segmentation and classification using support vector machines. The robustness of each algorithm was tested on multiple sets of images of mango trees acquired over a period of 3 years. These image sets were acquired under varying conditions (light and exposure), distance to the tree, average number of fruit on the tree, orchard and season. For images collected under the same conditions as the calibration images, estimated fruit numbers were within 16 % of actual fruit numbers, and the F1 measure of detection performance was above 0.68 for these methods. Results were poorer when models were used for estimating fruit numbers in trees of different canopy shape and when different imaging conditions were used. For fruit-background segmentation, K-nearest neighbour pixel classification based on colour and smoothness or pixel classification based on super-pixel over-segmentation, clustering of dense scale invariant feature transform features into visual words and bag-of-visual-word super-pixel classification using support vector machines was more effective than simple contrast and colour based segmentation. Pixel classification was best followed by fruit detection using an elliptical shape model or blob detection using colour filtering and morphological image processing techniques. Method results were also compared using precision–recall plots. Imaging at night under artificial illumination with careful attention to maintaining constant illumination conditions is highly recommended. 相似文献
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Line-scan hyperspectral imaging system for real-time inspection of poultry carcasses with fecal material and ingesta 总被引：1，自引：0，他引：1
Seung Chul Yoon Bosoon ParkKurt C. Lawrence William R. WindhamGerald W. Heitschmidt 《Computers and Electronics in Agriculture》2011,79(2):159-168
In poultry processing plants, fecal material and ingesta are the primary source of carcass contamination with microbial pathogens. The current practice of the poultry inspection in the United States is primarily human visual observations. Since the visual inspection is becoming more challenging in poultry processing plants adopting high-speed lines, a rapid sorting system could significantly improve the detection and monitoring of carcasses with surface fecal material and ingesta. As a result, we developed a prototype line-scan hyperspectral imaging system configured as a real-time multispectral imaging subsystem for online detection of surface fecal material and ingesta. Specifically, we integrated a commercially available off-the-shelf hyperspectral image camera into the system with two line lights and a custom software program for real-time multispectral imaging. The bottleneck of the imaging system was the data acquisition. For that reason, a multithreaded software architecture was designed and implemented not only to meet the application requirements such as speed and detection accuracy, but also to be customizable to different imaging applications such as systemic disease detection in the future. The image acquisition and processing speed tests confirmed the system could operate to scan poultry carcasses in commercial poultry processing plants. The fecal detection algorithm was based on the previous research using different hyperspectral imaging systems. A new carcass detection and image formation algorithm was developed to allow existing image processing and detection algorithms reusable without any modifications. Sixteen chicken carcasses and four different types of fecal and ingesta samples were used in a study to test the imaging system at two different speeds (140 birds per minute and 180 birds per minute) in a pilot-scale poultry processing facility. The study found that the system could grab and process three waveband images of carcasses moving up to 180 birds per minute (a line-scan rate 286 Hz) and detect fecal material and ingesta on their surfaces. The detection accuracy of the system varied between 89% and 98% with minimum false positive errors (less than 1%), depending on tested detection algorithms. Therefore, these findings provide the basis of not only a commercially viable imaging platform for fecal detection but also a single poultry inspection system for multiple tasks such as systemic disease detection and quality sorting. 相似文献
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Xin ZhangDaoliang Li Wenzhu YangJinxing Wang Shuangxi Liu 《Computers and Electronics in Agriculture》2011,78(1):71-79
Foreign fibers in cotton seriously affect the quality of cotton products. The identification of foreign fibers in cotton is a critical step in the automated inspection of foreign fibers in cotton; image segmentation is crucial in this identification process. This paper presents a new approach for segmenting images of foreign fibers in cotton. Firstly, color images were captured, and the edge of color images were detected by an edge detection method based on improved mathematical morphology. The color images were subsequently converted into a gradient map, the law of experience values was analyzed, and the best thresholding value of the gradient map was chosen by selecting the best experience value iteratively. The experiment results indicate that the proposed method successfully segments the high-resolution color images of cotton foreign fibers both directly and precisely. Furthermore, the speed of image processing is much faster than that of conventional methods. 相似文献
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To detect various common defects on oranges, a hyperspectral imaging system has been built for acquiring reflectance images from orange samples in the spectral region between 400 and 1000 nm. Oranges with insect damage, wind scarring, thrips scarring, scale infestation, canker spot, copper burn, phytotoxicity, heterochromatic stripe, and normal surface were studied. Hyperspectral images of samples were evaluated using principal component analysis (PCA) with the goal of selecting several wavelengths that could potentially be used in an in-line multispectral imaging system. The third principal component images using six wavelengths (630, 691, 769, 786, 810 and 875 nm) in the visible spectral (VIS) and near-infrared (NIR) regions, or the second principal component images using two wavelengths (691 and 769 nm) in VIS region gave better identification results under investigation. However, the stem-ends were easily confused with defective areas. In order to solve this problem, representative regions of interest (ROIs) reflectance spectra of samples with different types of skin conditions were visually analyzed. The researches revealed that a two-band ratio (R875/R691) image could be used to differentiate stem-ends from defects effectively. Finally, the detection algorithm of defects was developed based on PCA and band ratio coupled with a simple thresholding method. For the investigated independent test samples, accuracies of 91.5% and 93.7% with no false positives were achieved for both sets of selected wavelengths using proposed method, respectively. The disadvantage of this algorithm is that it could not discriminate between different types of defects. 相似文献
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In this study, real-time disease monitoring was conducted on onion which is the most representative crop in Republic of Korea, using an image acquisition system newly developed for the mobile measurement of phenotype. The purpose of this study was to improve the accuracy of prediction of disease and state variables by processing images acquired from monitoring. The image acquisition system was consisted of two parts, a motorized driving system and a PTZ (pan, tilt and zoom) camera to take images of the plants. The acquired images were processed as follows. Noise was removed through an image filter and RGB (red, green and blue) colors were converted to HSV (hue, saturation and value), which enabled thresholding of areas with different colors and properties for image binarization by comparing the color of onion leaf with ambient areas. Four objects with the most significant browning in the onion leaf to the naked eye were selected as the samples for data acquired. The thresholding method with image processing was found to be superior to the naked eye in identifying accurate disease areas. In addition, it was found that the incidence of disease was different in each disease area ratio. As a result, the use of image acquisition system in image processing analysis will enable more prompt detection of any changes in the onion and monitoring of disease outbreaks during the crop lifecycle. 相似文献
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水果采摘机器人视觉系统的目标提取 总被引：10，自引：3，他引：10
在田间对作物的果实图像进行实时、准确地目标识别提取，是采摘机器人视觉系统的关键技术，而目标提取的实质是图像分割。大部分水(蔬)果处于采摘期时，表面颜色与背景颜色存在较大差异。而同一品种果实表面颜色相近，体现为在色彩空间果实表面颜色和背景颜色存在着不同的分布特性。根据这一特性，提出了一种基于色彩空间参照表的适用于水果采摘机器人视觉系统果实目标提取的图像分割算法。该算法先由果实样本图像建立色彩空间参照表，再根据色彩空间参照表采用一种类似于“卷积”的方法进行图像分割。与现有其他方法比较，本方法基于彩色的信息处理，可将背景除去得更干净；对背景不做分割处理、无复杂运算，有利于机器人实时图像处理。采用该算法分别对草莓、橙子、西红柿的图像在L^*n^*6^*，Hsv，YCbCr色彩模型下进行了实验，结果显示该算法在这些色彩模型下均可取得理想的图像分割效果。 相似文献
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脐橙表面农药残留的计算机视觉检测方法研究 总被引：6，自引：2，他引：4
经不同种类农药处理后,采集脐橙激光散射图像,通过对表面是否喷洒农药,以及表面喷洒不同种类农药的水果图像进行处理,用一元非线性方程拟合脐橙图像灰度值分布曲线。结果表明,脐橙图像灰度值在10~100范围内的灰度曲线拟合模型与农药残留是密切相关的,能用于区分脐橙表面是否存在农药残留。 相似文献
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At an early immature growth stage of citrus, a hyperspectral camera of 369–1042 nm was employed to acquire 30 hyperspectral images in order to detect immature green fruit within citrus trees under natural illumination conditions. First, successive projections algorithm (SPA) were implemented to select 677, 804, 563, 962, and 405 nm wavebands and to construct multispectral images from the original hyperspectral images for further processing. Then, histogram threshold segmentation using NDVI of 804 and 677 nm was implemented to remove image backgrounds. Three slope parameters, calculated from the pairs 405 and 563 nm, 563 and 677 nm, and 804 and 962 nm were used to construct a classifier to identify the potential citrus fruit. Then, a marker-controlled watershed segmentation based on wavelet transform was applied to obtain potential fruit areas. Finally, a green fruit detection model was constructed according to Grey Level Co-occurrence Matrix (GLCM) texture features of the independent areas. Three supervised classifiers, logistic regression, random forest and support vector machine (SVM) were developed using texture features. The detection accuracies were 79%, 75%, and 86% for the logistic regression, random forest, and SVM models, respectively. The developed algorithm showed a great potential for identifying immature green citrus for an early yield estimation. 相似文献
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为系统、全面地分析不同颜色指数对南方稻田图像分割的适应性,以分蘖期、拔节期稻田图像为研究对象,选择36种常用的颜色指数,采用Otsu阈值法开展基于颜色指数和阈值的图像分割研究,通过比较各颜色指数的分割结果,明确分蘖期和拔节期图像分割的主要干扰因素,筛选最适宜稻田图像分割的颜色指数。结果表明：水稻倒影、浮萍是分蘖期稻田图像分割的主要干扰因素,叶片镜面反射、浮萍和土壤阴影是拔节期稻田图像分割的主要干扰因素;组合指数COM2、MxEG、CIVE和GMR在分蘖期图像和拔节期图像均具有较好的分割精度。因此,基于颜色指数COM2、MxEG、CIVE、GMR和Otsu阈值的稻田图像分割方法对稻田图像分割的干扰要素具有较强的区分能力,分割精度较高,更适宜于南方稻田图像处理研究。 相似文献
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水稻根系形态特征的定量研究对于改进农田管理方式、水稻品种选育和遗传改良等具有重要意义。近年来,随着表型组技术迅速发展,利用图像处理技术对水稻根系生长情况进行测量和分析,同时配合施肥、灌溉、光照、温控等环境监控技术已成为水稻育种和功能基因组研究新型技术手段,而根系图像分割技术是进行后续表型组学分析的重要基础之一。由于生长在土壤中的水稻根系图像具有对比度低、信噪比低、纹理复杂的特点,分割十分困难。针对此问题,研究了主干-分支连接算法、基于形态特征的局部阈值分割算法和基于形态特征的自适应阈值分割算法,对生长在土壤中水稻根系图像进行分割处理和比较。实验结果表明,主干-分支连接算法虽然保留了大量细节,但是受噪声影响严重,其结构略显杂乱,毛刺现象严重;基于形态特征的局部阈值分割算法能保留更多根部的细节,但轮廓断裂的现象比较严重;自适应阈值分割算法分割的图像根系连续性较好,毛刺现象也得到了抑制,但是细小的须根无法保留。最终将两种算法结合起来,提出一种适用于水稻表层根系图像分割的综合算法,则可以获得较为理想的分割结果,为后续水稻根系性状提取奠定了重要基础。 相似文献
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为了解决现有果树树叶稀密程度检测方法要求采集图像时采用标准白板标定或固定成像距离的问题,本文提出一种新的基于图像处理技术的检测果树树叶稀密程度的方法——最大轮廓矩形法。该方法采用超绿色法、Ostu、中值滤波去噪、腐蚀和膨胀等图像处理技术将果树图像有效分割出来,通过检测经图像处理后的二值图像中整棵果树最大轮廓所占的面积,再检测整幅图像中树叶与树干所占的面积,根据果树树叶稀密程度的定义即可计算树叶稀密程度。结果表明,该方法不需要固定成像距离和使用白板标定,最大轮廓矩形法对果树图像面积的检测是因果树实际图像而异的,不存在现有方法统一采用相机所设定的图像大小作为最大轮廓而导致所检测到的树叶稀密程度偏小的问题;20张果树样本图像采用两种方法检测的果树树叶稀密程度的最大差值为0．2950,最小差值为0．0027。 相似文献
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基于线扫描的机器视觉成像系统，用于采集铁轨表面图像，提出一种以图像增强和自动阈值分割为核心的缺陷检测算法，该算法能够准确检测出铁轨表面缺陷.图像增强采用局部零均值法，克服了铁轨表面光线反射不均的缺点，提高了缺陷和背景的区分度.自动阈值分割采用强调概率的最大背景类方差法，取到的阈值使背景类方差最大的同时保持缺陷出现概率较小.将本文的核心方法与传统方法进行对比实验，验证了该算法的有效性和快速性，具有一定的实用价值. 相似文献