基于H分量旋转的色盲矫正方法

为提高色盲患者的色彩分辨力,提出一种基于H分量旋转的色盲矫正方法.在颜色的HIS空间,利用H分量的连续性和周期性特点,在保持S、I分置不变的情况下,通过旋转H分量得到矫正图像,该图像以降低低频颜色的分辨率来换取高频颜色的分辨率提高.实验表明:在色盲类型给定且图像颜色是给定色盲易混淆的情况下,对H分量旋转120度能得到色彩分辨效果很好的矫正图像.     

基于纹理统计特征的医学图像颜色映射方法

为提高灰度医学图像颜色增强的有效性和视觉合理性,提出了一种基于纹理统计特征的颜色增强处理方法。此方法的颜色映射机理不是传统的在灰度级和颜色模型间经验性构筑一对一或多对一的映射关系函数,而是借助彩色可视化人体（VHP）解剖断层源图像数据,利用共生矩阵纹理统计特征信息,实现颜色在图像间的传输。实验结果证明了此方法的可行性,高维度、高阶数统计量的运用提高了颜色映射的准确性和有效性。     

基于深度学习网络的医学核磁共振成像超分辨率重构实验

基于深度学习网络的医学核磁共振（MR）图像超分辨重建实验研究,提出并构建一个大规模的高质量用于MR图像超分辨的数据集,涵盖了头颅、膝盖、乳房以及头颈4个部位。通过数据质量筛选和不同低分辨率图像生成方式,在原始图像的高分辨率基础下,以×2、×3、×4的下采样尺度,原始MRI图像形成3种不同尺度下的MR图像数据集,同时给出不同部位超分辨难易程度分析。采用7个在自然图像的超分辨率领域中取得最好效果的深度学习网络,将它们迁移到MR图像中,学习低分辨率MR图像到高低分辨MR图像的映射关系,并对比分析这些深度学习网络在自然图像的超分辨效果。通过实验可以看出,深度学习网络在MR图像超分辨取得了比传统算法更好的效果,部分结果不亚于自然图像;不同部位的超分辨效果差异较大,难以以一个深度学习网络使不同部位均具有更好的超分辨效果。深度学习网络在MR图像超分辨将具有重要的应用价值和理论意义。     

冠脉树三维重建中几何变换矩阵的优化

冠脉造影图像间的几何变换矩阵是实现冠脉树三维重建的关键。本研究分析了优化几何变换矩阵的必要性，提出利用分支点坐标、分支血管方向矢量和分支夹角三类数据优化几何变换矩阵的方法，并给出了kvenberg-Marquardt算法的优化步骤。最后利用两幅未标定的单面冠脉造影图像，实现冠脉树骨架的三维重建。重建的误差统计结果表明，优化方法有效地提高了冠状动脉树三维重建的精度。     

59例色盲患者临床与家系调查分析

本文对邢台市5所中小学校27个班级、1487名男女在校学生的色盲调查资料,进行了整理分析,认为资料基本上反映了学生的患病情况,27个班级应查学生1620人,实查1487人,实查率92%,查出色盲患者59名,发病率3.97%,其中调查男学生803名,色盲患者43名,男性色盲发病率5.35%;调查女学生684人,色盲患者16名,女性色盲发病率2.34%,对查出的色盲患者进行了家系调查。     

冠状动脉树结构的三维重建

由于双平面X射线造影系统只能提供两幅有限的投影数据 ,冠状动脉树的三维重建在匹配、优化几何变换矩阵等方面存在困难。研究了冠状动脉树结构的特征点自动识别方法 ,提出几何变换矩阵的优化方法和一种新型、简便的分段匹配方法。通过对两幅X射线造影图像进行细化、分割和匹配等处理 ,实现了冠状动脉树结构的三维重建。     

基于Zadeh-X变换的图像隐藏和挖掘技术

提出了用于底层图像挖掘和隐藏的Zadeh—X变换方法，同时巧妙的运用了人类视觉的对比度分辨率限制（只能分辨大于5个灰度／色度级的图像成份）对图像进行隐藏和挖掘。我们首先通过图像的灰度谱，获取图像的灰度分布信息，然后用Zadeh—X变换对原始图像进行白、黑或其它背景颜色的隐藏，隐藏后的图像具有很好的伪装性。我们同样也可用Zadeh—X变换从隐藏后的图像中把原始图像不失真地恢复出来。     

基于小波变换的异常特征超声图像定位技术

为了提高超声图像的诊断识别能力,需要进行异常特征点定位。提出一种基于小波变换的异常特征超声图像定位技术。对采集的超声图像采用边界特征融合方法进行边缘轮廓检测,在邻域内采用颜色梯度分解方法进行超声图像区域融合滤波处理,结合小波变换方法进行超声图像的特征分解和尺度模板匹配,提取超声图像的奇异特征点,根据超声图像的颜色特征分解值进行邻域均衡控制和自适应特征参量估计,根据超声图像的纹理和颜色特征提取结果进行图像的异常特征点定位检测和识别。仿真结果表明,采用该方法进行超声图像异常特征点定位的准确度较高,定位精度较好,提高了超声图像的异常特征辨识能力。     

基于颜色直方图的新疆维吾尔医药材图像特征提取与判别分析

图像特征提取是图像处理的一个主要环节,是图像处理技术研究和应用的一个重要领域。维吾尔医是我国的传统医学,越来越受到人们的重视,但大量的维吾尔医药材的数据资料没有得到充分利用。本文针对新疆维吾尔药材的植物药和动物药图像提取了颜色直方图特征。先对图像进行颜色增强、尺寸归一、空间转换的预处理,提取颜色直方图特征并对颜色直方图特征进行统计学分析,最后应用Bayes判别分析法对特征的分类能力进行评价。实验结果表明颜色直方图特征对维吾尔药图像分类有较高的准确率,一定程度上有助于基于内容的新疆维吾尔药材图像的检索的研究。     

眼底图像的三维重建

根据简化眼模型和眼底照相机光学系统简化模型建立了眼底图像三维重建的数学模型,分析了正常眼和屈光异常眼眼底图像与真实眼底视网膜形状的关系,导出了眼底二维平面图像到三维曲面图像的映射关系,最后给出了对眼底图像进行三维重建的实例.眼底三维重建图像的最大视场取决于眼底照相机的最大视场角,该最大视场角限制了重建图像的视场大小和三维重建时z轴的取值范围.根据给出的三维重建映射公式对眼底图像的二维数据进行三维映射后,再进行纹理映射,即可绘出重建后的三维眼底图像.该方法利用现有二维成像设备提供患者眼底三维重建图像,可为眼科医生在临床诊断和治疗时提供有益的参考和帮助.     

生物形式的辐射辨识坐标——颜色

实验建立了颜色的数据标识,但并未对颜色构成所具备的数学特征做出解释.以单色辐射和线性连续辐射为基本的物理分析模型,结合线性辐射存在的数学条件,构造了光辐射辨识的数学模型.根据该数学模型,可对颜色表现出来的所有数学特征做出较为全面的诠释.由此表明,颜色的数学本质其实就是生物形式的辐射辨识坐标.     

Bipolar cell pathways for color and luminance vision in a dichromatic mammalian retina

The mammalian retina is fundamentally dichromatic, with trichromacy only recently emerging in some primates. In dichromats, an array of short wavelength-sensitive (S, blue) and middle wavelength-sensitive (M, green) cones is sampled by approximately ten bipolar cell types, and the sampling pattern determines how retinal ganglion cells and ultimately higher visual centers encode color and luminance. By recording from cone-bipolar cell pairs in the retina of the ground squirrel, we show that the bipolar cell types sample cone signals in three ways: one type receives input exclusively from S-cones, two types receive mixed S/M-cone input and the remaining types receive an almost pure M-cone signal. Bipolar cells that carry S- or M-cone signals can have a role in color discrimination and may contact color-opponent ganglion cells. Bipolar cells that sum signals from S- and M-cones may signal to ganglion cells that encode luminance.     

Is Skin Color a Marker for Racial Discrimination? Explaining the Skin Color–Hypertension Relationship

It is widely assumed that dark-skinned Blacks have higher rates of hypertension than their lighter-skinned cohorts because the former experience greater racial discrimination. However, there is no empirical evidence linking skin color to discrimination. This study tested the extent to which skin color is associated with differential exposure to discrimination for a sample of 300 Black adults. Results revealed that dark-skinned Blacks were 11 times more likely to experience frequent racial discrimination than their light-skinned counterparts; 67% of subjects reporting high discrimination were dark-skinned and only 8.5% were light-skinned. These preliminary findings suggest that skin color indeed may be a marker for racial discrimination and highlight the need to assess discrimination in studies of the skin color–hypertension relationship.     

Multiple Redundant Medulla Projection Neurons Mediate Color Vision in Drosophila

The receptor mechanism for color vision has been extensively studied. In contrast, the circuit(s) that transform(s) photoreceptor signals into color percepts to guide behavior remain(s) poorly characterized. Using intersectional genetics to inactivate identified subsets of neurons, we have uncovered the first-order interneurons that are functionally required for hue discrimination in Drosophila. We developed a novel aversive operant conditioning assay for intensity-independent color discrimination (true color vision) in Drosophila. Single flying flies are magnetically tethered in an arena surrounded by blue and green LEDs (light-emitting diodes). The flies’ optomotor response is used to determine the blue-green isoluminant intensity. Flies are then conditioned to discriminate between equiluminant blue or green stimuli. Wild-type flies are successfully trained in this paradigm when conditioned to avoid either blue or green. Functional color entrainment requires the function of the narrow-spectrum photoreceptors R8 and/or R7, and is within a limited range, intensity independent, suggesting that it is mediated by a color vision system. The medulla projection neurons, Tm5a/b/c and Tm20, receive direct inputs from R7 or R8 photoreceptors and indirect input from the broad-spectrum photoreceptors R1–R6 via the lamina neuron L3. Genetically inactivating these four classes of medulla projection neurons abolished color learning. However, inactivation of subsets of these neurons is insufficient to block color learning, suggesting that true color vision is mediated by multiple redundant pathways. We hypothesize that flies represent color along multiple axes at the first synapse in the fly visual system. The apparent redundancy in learned color discrimination sharply contrasts with innate ultraviolet (UV) spectral preference, which is dominated by a single pathway from the amacrine neuron Dm8 to the Tm5c projection neurons.     

Conditions for view invariance in the neural response to visual symmetry

Symmetry detection is slow when patterns are distorted by perspective, perhaps due to a time‐consuming normalization process, or because discrimination relies on remaining weaker regularities in the retinal image. Participants viewed symmetrical or random dot patterns, either in a frontoparallel or slanted plane (±50°). One group performed a color discrimination task, while another performed a regularity discrimination task. We measured a symmetry‐related event‐related potential (ERP), beginning around 300 ms. During color discrimination, the ERP was reduced for slanted patterns, indexing only the remaining retinal structure. During regularity discrimination, the same ERP was view invariant, and identical for frontoparallel or slanted presentation. We conclude that normalization occurs rapidly during active symmetry discrimination, while symmetry‐sensitive networks respond only to regularity in the retinal image when people are attending to other features.     

基于色差评定理论的尿液生化分析方法研究

尿液生化分析是医院临床重要的检查诊断手段.常规尿液分析方法主要有比色目视评价和自动化检测,其中比色目视评价方法已基本被淘汰;自动化检测方法多为医院采用,市场上的尿液生化分析仪价格一般在两万元左右,难以走进普通家庭.计算机视觉不受人的生理和心理因素影响,评价客观、稳定.为此,依据颜色理论,建立计算机视觉系统,对标准阈值颜色和与尿液反应后尿试纸的颜色进行采集、处理、显示和色差评价,便可准确地判定病情级别.我们介绍一种新颖的、方便操作的,可普及于家庭的尿液生化分析方法.实验结果表明,此方法方便、廉价、检测迅速、可实现全程监控,应用前景十分光明.     

序列解剖层片的全局和局部色彩校正

本研究提出了一种全局和局部相结合的序列解剖层片的色彩校正算法。利用数字人层片（中国女婴一号）上提供的彩色灰度卡对相邻层片间各颜色通道的色彩差异进行全局校正，以消除解剖数据集沿垂直方向的光照变化；再利用线性校正模型和差值图像各通道（R、G、B）的灰度局部直方图，对解剖数据集进行局部色彩差异校正。重建结果表明，经过全局和局部色彩校正后，重建视图中的明暗条纹基本消失，说明层片间颜色的不连续现象得到了校正。     

基于特征融合的U-Net肺自动分割方法

目的:将肺部颜色特征与纹理特征融合形成一种更有效的特征,并利用改进的U-Net深度学习网络结构对肺部CT影像进行图像分割以准确提取肺实质区域。方法:使用的CT影像数据来源于LIDC-IDRI数据库,首先通过色彩空间转换、高阶邻域统计的方法分别提取颜色特征和纹理特征,然后采用加权平均直方图融合两类特征,最后将特征输入改进后的U-Net模型,进行1 000次CT扫描测试,以达到完整的肺实质输出。结果:该方法最终的骰子系数、灵敏度、特异性分别为93%、96%和97%。结论:本方法较单一特征分割方法具有较高的分割精度,有效提高肺实质的分割精度,可为后续的肺部疾病自动诊断提供可靠基础,减少临床诊断的成本并节省医生诊断时间。     

A high-resolution three-dimensional far-infrared thermal and true-color imaging system for medical applications

As the needs for various kinds of body surface information are wide-ranging, we developed an imaging-sensor integrated system that can synchronously acquire high-resolution three-dimensional (3D) far-infrared (FIR) thermal and true-color images of the body surface. The proposed system integrates one FIR camera and one color camera with a 3D structured light binocular profilometer. To eliminate the emotion disturbance of the inspector caused by the intensive light projection directly into the eye from the LCD projector, we have developed a gray encoding strategy based on the optimum fringe projection layout. A self-heated checkerboard has been employed to perform the calibration of different types of cameras. Then, we have calibrated the structured light emitted by the LCD projector, which is based on the stereo-vision idea and the least-squares quadric surface-fitting algorithm. Afterwards, the precise 3D surface can fuse with undistorted thermal and color images. To enhance medical applications, the region-of-interest (ROI) in the temperature or color image representing the surface area of clinical interest can be located in the corresponding position in the other images through coordinate system transformation. System evaluation demonstrated a mapping error between FIR and visual images of three pixels or less. Experiments show that this work is significantly useful in certain disease diagnoses.     

基于神经元颜色拮抗与动态编码的轮廓检测方法

基于神经元的颜色拮抗特性及神经元群体的动态编码机制,实现对图像的轮廓检测。模拟视皮层下神经元的颜色单拮抗特性,引入单拮抗感受野的动态调节机制,以充分响应颜色边界和亮度边界;利用单细胞的树突极性分布,构建初级视皮层的双拮抗神经元网络,实现对特定方位的视觉刺激响应,有效提取目标轮廓;在神经元的群体感受野内,考虑神经元的动态突触连接,融合单细胞的脉冲频率响应,实现对纹理信息的抑制作用。以BSDS500图库的图像为实验对象,结果显示该方法在提取主体轮廓的过程中能有效抑制纹理信息,其对100幅图像最佳检测结果的P值指标均值和标准差为0.58±0.04,相对CORF和CO等其他对比方法,可提高轮廓提取的准确率。所提出方法可有效实现图像的轮廓检测,为利用颜色信息以及神经元之间的动态编码、实现更高级皮层的图像理解或者视觉认知提供新的思路。