数字图像处理模拟题(双语课)

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数字图像处理题库(87道)

数字图像处理1、in the hardware peripherals of image processing, which of the following equipments does not belong to the input devices?——[单选题]A Electron cameraB CCD video cameraC Desktop image scannerD Light tape正确答案：D2、The number of bits required to store an 1024*512 image of 4 gray levels is ( )——[单选题]A 256KB 512KC 1MD 2M正确答案：C3、An image of size 1024 × 1024 pixels in which the intensity of each pixel is an8 bit quantity requires the storage space ( if not compressed).——[单选题]A 1 KBB 1 MBC 2 KBD 2 MB正确答案：B4、Intensity range of 8-bit pixel image is （） .——[单选题]A 0 to 7B 0 to 15C 0 to 31D 0 to 255正确答案：D5、By its very nature, the appearance of false contours in image is because ( )——[单选题]A the number of gray levels of the image is not enoughB the spatial resolution of the image is not high enoughC the number of gray levels of the image is excessiveD the spatial resolution of the image is too enough正确答案：A6、In the process of image sampling and quantization, the appearance of checkboard effect is because ( )——[单选题]A the number of gray levels of the image is not enoughB the spatial resolution of the image is not high enoughC the number of gray levels of the image is excessiveD the spatial resolution of the image is too enough正确答案：B7、When you enter a dark room on a bright day, it takes some time to see well enough, this is the visual process or visual phenomenon of——[单选题]A Brightness adaptationB Brightness discriminationC Optical illusionD Simultaneous contrast正确答案：A8、Sampling of an image is required for （）.——[单选题]A QuantizationB SharpeningC SmoothingD Digitization正确答案：D9、An image function f(x,y) is characterized by f(x,y)=i(x,y)r(x,y) where.——[单选题]A 0<i(x,y)<1&0<r(x,y)<∞B 0<i(x,y)<1&0<r(x,y)<1C 0<i(x,y)<∞&0<r(x,y)<∞D 0<i(x,y)<∞&0<r(x,y)<1正确答案：D10、A pixel p at coordinates (x,y) has four horizontal and vertical neighbours whose coordinates are given by.——[单选题]A (x-1,y-1),(x-1,y),(x,y-1),(x,y+1)B (x+1,y),(x-1,y),(x,y+1),(x,y-1)C (x+1,y-1),(x-1,y),(x-1,y+1),(x,y+1)D (x+1,y-1),(x-1,y),(x,y+1),(x-1,y+1)正确答案：B11、The D4 distance (city distance) between p and q with coordinates (x,y), (s,t) is defined as.——[单选题]ABCD正确答案：A12、Mach bands effect——[单选题]A can be analyzed using simutaneous contrastB depends on the brightness adaptive level of human visual systemC indicates the same fact as simutaneous contrastD indicates that the actual brightness distributions of the bands are influenced by the subjective brightness curve正确答案：C13、The lens focuses light from objects onto the——[单选题]A corneaB retinaC scleraD iris正确答案：B14、The spatial resolution of an image is determined by how ( ) was carried out.——[单选题]A QuantizationB SharpeningC SmoothingD Sampling正确答案：D15、In the human visual system, the perceived intensity of a region is related to the light intensities of the regions surrounding it, this is called ( ).——[单选题]A brightness adaptationB simultaneous contrastC brightness discriminationD optical illusions正确答案：B16、The colours of an object that we perceive are determined by the nature of( ).——[单选题]A the light reflected from the objectB the light shone onto the objectC the light absorbed by the objectD the external light正确答案：A17、The human visual system can perceive approximately different light intensity levelsHowever, at any one time we can only discriminate between a much smaller number,this is indicated in the phenomenon called ( ).——[单选题]A Brightness adaptationB Brightness discriminationC Optical illusionD Simultaneous contrast正确答案：A18、Suppose there is a pixel p at coordinates (x,y), it's diagonal neighbor has four pixels, whose coordinates are given by ( ).——[单选题]A (x-1,y-1),(x-1,y),(x,y-1),(x,y+1)B (x-1,y-1),(x+1,y-1),(x-1,y+1),(x+1,y+1)C (x+1,y-1),(x-1,y),(x-1,y+1),(x,y+1)D (x+1,y-1),(x-1,y),(x,y+1),(x-1,y+1)正确答案：B19、The distance (chessboard distance) between p and q with coordinates (x,y), (s,t) is defined as. ——[单选题]ABCD20、In Matlab, which command can we use to dispaly an image?——[单选题]A imreadB imshowC imhistD imwrite正确答案：B21、In matlab, suppose x=[1 2 3 4;5 6 7 8;9 10 11 12]，after run the commandx(:,[2,3])=[];what is the size of x?——[单选题]A 1*4B 3*2C 3*4D 3*3正确答案：B22、In matlab command window, if we run the followong command,what is the result shown in the command window？X=[1 2 3 4;5 6 7 8;9 10 11 12];X(5)——[单选题]A 5B 6C 0D 10正确答案：B23、In Matlab，Suppose x is a 1*6 array，which command can delete the fifth element of x？——[单选题]A delete x(5)B delete x(4)C x(5)=[]D x(4)=[]正确答案：C24、In MATLAB，what is the result of the expression 3~=4？——[单选题]A 1B 0C 7D 1225、In matlab, the command "clear" is used to ( )——[单选题]A Shows the variable in the workspaceB Deletes all variables in the workspaceC clean the command windowD clean the figure window正确答案：B26、In MATLAB，what is the result of x after run the command x=1:2:10？——[单选题]A 1 2 3 4 5 6 7 8 9 10B 1 3 5 7 9 11C 1 3 5 7 9D 2 4 6 8 10正确答案：C27、if x=2.6 ,what is the result of round(x), floor(x), ceil(x) and fix(x)?——[单选题]A 2,2,3,2B 3,2,3,2C 3,2,3,3D 2,2,3,3正确答案：B28、In MATLAB，what is the result of the expression 3==3？——[单选题]A 1B 0C 7D 12正确答案：A29、if x=-2.6 ,what is the result of round(x), floor(x), ceil(x) and fix(x)?——[单选题]A -2,-3,-2,-2B -3,-3,-2,-2C -3,-3,-2,-3D -2,-3,-2,-330、In matlab, the command "save" is used to ( )——[单选题]A Shows the variable in the workspaceB Saves all variables in the workspace to diskC clean the command windowD clean the figure window正确答案：B31、In MATLAB，what is the result of x after run the command x=10:-2:1？——[单选题]A 10 9 8 7 6 5 4 3 2 1B 10 8 6 4 2 0C 10 8 6 4 2D 2 4 6 8 10正确答案：C32、In Matlab, which command can we use to read an image?——[单选题]A imshowB imreadC imhistD imwrite正确答案：B33、In MATLAB, what is the result of a(5) after run these two commands?A=[1 2 3 4]；A(6)=6;——[单选题]A 6B 5C 4D 0正确答案：D34、In Matlab，Suppose x is a 2*3 array，which command can delete the 5th elementof x？——[单选题]A delete x(5)B delete x(4)C x(4)=[]D x(5)=[]35、In matlab, suppose x=[1 2 3 4;5 6 7 8;9 10 11 12]，after run the commandx([1,3],:)=[];what is the size of x?——[单选题]A 3*2B 1*4C 3*4D 3*3正确答案：B36、In matlab，suppose x is a 3*4 matrix，after run the following command，what is the size of x？X=[1 2 3 4;5 6 7 8;9 10 11 12];Y=x(2,2:4);X=[x,y'];——[单选题]A 3*4B 4*3C 3*5D 5*3正确答案：C37、in Matlab，if we want to display four images in the same figure window as the layout shown in the following，which command do we need to use to display an image in the area 2?——[单选题]A subplot(1,4,2)B subplot(4,1,2)C subplot(2,2,2)D subplot(2,2,3)正确答案：C38、In matlab, suppose x=[1 2 3 4;5 6 7 8;9 10 11 12]，after run the commandx=[x;13 14 15 16];what is the size of x?——[单选题]A 3*5B 4*4C 3*4D 3*3正确答案：B39、In Matlab，Suppose x is a 1*6 array，which command can add 3 elements to x？——[单选题]A add x(7:9)B add x(3)C x(9)=10D x(9)=[]正确答案：C40、The corresponding relations between an image and its gray histogram is ( )——[单选题]A one to oneB many-to-oneC one-to-manyD all false正确答案：B41、There is a light ring on the dark background of a gray level image, can be used to make the ring thinner.——[单选题]A Median filterB Max filterC Min filterD Midpoint filter正确答案：C42、In the following four operators, which one belongs to the secondderivative? .——[单选题]A SobelB RobertsC PrewittD Laplacian正确答案：D43、When powerlaw transformation is used to as grayscale transformation,Which type of images as follows can be the transformationPerformed on for enhancement if the power is over 1?——[单选题]A Overall image intensities are on the dark sideB Overall image intensities are on the bright sideC Image details are hidden in the dark backgroundD Images have both too bright and too dark background正确答案：B44、( )can be applied for motion detection.——[单选题]A additionB substactionC multiplicationD division正确答案：B45、In the following four filters, which one belongs to a linear filter?——[单选题]A Median filterB Averaging filterC Max filterD Min filter正确答案：B46、The purpose of compressing dynamic range of image graylevles can be achieved with the help of logarithmic transformation , because ( )——[单选题]A graylevels dynamic range before transformation is larger than that after transformationB only partial range of graylevel values ha been taken after transformationC the ranges of graylevel before and after the transformation are differentD logarithmic transformation curve is monotonically increasing curve正确答案：B47、Logarithmic transform is useful if we wish to enhance details in the ( ) areas of the image, but at the expense of details in the ( ) areas.——[单选题]A dark darkB dark brightC bright darkD bright bright正确答案：B48、The range of intensity change of certain scene image obtained from camera is called ( ),which is the range from the darkest to the brighest in an image.——[单选题]A gray levelB dynamic rangeC spatial resolutionD histogram正确答案：B49、The gray level of an overexposed (washed out) image focuses on ( ) range, while the gray level of an underexposed image focuses on ( ) range.——[单选题]A low-brightness ,low-brightnessB low-brightness ,high-brightnessC high-brightness ,low-brightnessD high-brightness ,high-brightness正确答案：C50、Geometric transformation of images does not change the pixel's( ),but change the pixel's( ).——[单选题]A positon, valueB value,positionC contrast,positionD position, contrast正确答案：B51、Corresponding to different scene contents, digital image can be generally divided into three types, they are ( )——[多选题]A binary imageB gray imageC index imageD color image正确答案：ABD52、Which of the following adjacencies can eliminate ambiguity of path between pixels ( )——[多选题]A 4-adjacencyB 8-adjacencyC m-adjacencyD mixed adjacency正确答案：CD53、Image digitization process consists of two steps——[多选题]A samplingB transformationC quantizationD scanning正确答案：AC54、The retina is covered with light receptors called——[多选题]A rodsB conesC foveaD lens正确答案：AB55、Image digitization process consists of two steps，sampling and quantization. These two steps determine the ( ) and ( ) of an image, respectively.——[多选题]A Spatial resolutionB ResolutionC Intensity level resolutionD Dynamic domain正确答案：AC56、（Single choice）Which adjacency between pixels is the sufficient condition of other types of adjacency ？——[多选题]A 4-adjacencyB 8-adjacencyC m-adjacencyD mixed adjacency正确答案：A57、Three commonly-used neighbors in image processing are( )——[多选题]A 4-neighborsB 8-neighborsC diagonal neighborsD mixed neighbors正确答案：ABC58、MATLAB variable names ( )——[多选题]A must begin with a letterB can contain any combination of letters, numbers and underscore (_C must be unique in the first 31 charactersD can begin with a number正确答案：ABC59、The commonly-used histogram processing methods include ( ) and ( ).——[多选题]A histogram equalizationB histogram adjustmentC histogram specificationD histogram transform正确答案：AC60、The following spatial filters belonged to non-linear filters are ( )——[多选题]A median filterB max filterC min filterD averaging filter正确答案：ABC61、The cone body is mainly located in the middle part of the retina,and is highly sensitive to color. ——[判断题]A 正确B 错误正确答案：A62、The total range of distinct intensity levels the eye can discriminate simultaneously is rather small when compared with the total adaptation range. ——[判断题]A 正确B 错误正确答案：A63、The colours that we perceive are determined by the nature of the light absorbed by an object. ——[判断题]A 正确B 错误64、If a command is followed by a semicolon (;), result of the computation is not shown on the command window.——[判断题]A 正确B 错误正确答案：A65、If a command is followed by a commas (,), result of the computation is not shown on the command window——[判断题]A 正确B 错误正确答案：B66、In command window of Matlab, Ellipsis (…) means continuing on the next line.——[判断题]A 正确B 错误正确答案：A67、MATLAB is case sensitive: “name”, “Name” and “NAME” are consider ed different variables——[判断题]A 正确B 错误正确答案：A68、In Matlab, a two-dimensional matrix is stored in memory in Column major order.——[判断题]A 正确B 错误正确答案：A69、In MATLAB relational operators ,false is represented by 0 and true is represented by 1 (non-zero).——[判断题]A 正确B 错误70、Suppose x is a 3*4 matrix, then a(2,3) is the 8th element of x when in memory.——[判断题]A 正确B 错误正确答案：A71、In Matlab, imshow funtuntion can display images on the screen.——[判断题]A 正确B 错误正确答案：A72、Break statement terminates the execution of a loop and passes the control to the next statement after the end of the loop.——[判断题]A 正确B 错误正确答案：A73、Continue statement terminates the current pass through the loop and returns control to the top of the loop.——[判断题]A 正确B 错误正确答案：A74、In Matlab, the command window can input commands and show the results. ——[判断题]A 正确B 错误正确答案：A75、In the binary image, each pixel value is represented by 1 bit, value 1 represents white and value 0 represents ( )——[填空题]正确答案：black76、Consider the image segment shown .Two pixels p and q are at the locations shown in the figure, please compute their Euclidean（）,city-block （）andchessboard distances（）respectively。

西安交大数字图像处理双语试题

) An image is s degraded b by a Gaussia an blur who ose Fourier transform t H H(u,v) is a G Gaussian H (u, v ) e ( u v )/2 , 13. A
Sket tch the gray y level transformation fo for a gamma a transforma ation that wi ill produce t the image on n the right. mera capture es a 400x400 pixel imag ge of a black and white e soccer ball l on a gray b background. The 2. A digital cam ball is 30 cm in n diameter an nd is 3 m aw way from th he camera. T The camera has a field o of field of 90 9 degrees izontally and d vertically. . hori (a) W What is the diameter of f the ball in pixels, in th he image? (i) 3 pixels (ii) 10 pixels (ii i) 20 pixels (iii) 31 pixe els (iv) 63 p pixels (b) G Give the his stogram of t the image, a assuming tha at black, wh hite, and gra ay pixels hav ve the gray levels 0, 25 55, and 128, respec ctively. Assu ume that the ere are an eq qual number r of black an nd white pix xels on the b ball. g (table tenn nis) ball is 4 40 mm in diameter. How w far away must the pin ng-pong bal ll be, to be (c) A ping-pong exac ctly the sam me apparent size as the s soccer ball i in the image e? (i) 1 10 cm (ii) 0.4 m (iii) 0.7 75 m (iv) 1 m (v) 3 m era has an im mage resolu ution of 2000 x 2000 pix xels. The in ndividual sen nsor elemen nts are squar res 3. A CCD came mea asuring 10 x 10 um, wit th no spaces s between th hem. a. If f the camera a uses a lens s with focal length = 10 00 mm, wha at is the field d of view? b. A Assume the c camera is m mounted on a an airplane, pointing str raight down n at the grou und. What he eight should d the airplane fly, so that one pix xel in the ca amera corres sponds to on ne meter on n the ground d? 4. T The histogram m of a 100x x100 image with 3 bit p pixels is give en below.

数字图像处理模拟试题4套(含答案)

模拟试卷一1.对将一个像素宽度的8通路转换到4通路提出一种算法。

2.（A）试提出一种过程来求一个邻域的中值？（B）试提出一种技术，逐像素地移动领域的中心来更新中值。

（会了）3.证明如式所示的拉普拉斯变换是各向同性的（旋转不变）。

需要下列轴旋转角的坐标方程：其中为非旋转坐标，而为旋转坐标。

4.获得对应于式子到式子的带阻滤波器的带通滤波器的等式。

5.给定的图象，那么一个级金字塔是减少还是增加了表示图象所需的数据量？压缩或扩展率是多少？6.考虑灰度级数据{12，12，13，13，10，13，57，54}的一条8像素的线。

这条线已经经过精度为6比特的均匀量化。

构造它的3位IGS编码。

7.一个零记忆高斯信源率失真函数如下：请绘制出这个函数的曲线。

8.证明二元表达式的正确性。

模拟试卷一参考答案1.2.（A）在数字上拣取为的值，它的中值是的最大值。

（B）一旦值已经被分类一次，我们仅仅是删除在缓慢移动向附近的轨迹的值，插入首要移动的值到分类排列的最恰当位置。

3.4.带通滤波器是从1减去带阻滤波器获得的：然后：（a）理想的带通滤波器：（b） Butterworth带通滤波器：（c）高斯带通滤波器：5.数据的数量在这个级金字塔中是被限定在4/3之内的：又因为 ,因此我们可以得到以下的结果:6.7.8.模拟试卷二1.考虑以下所示的图像分割：（A）令并计算p和q间的4，8，m通路的最短长度。

如果在这两点间不存在特殊通路，请解释原因。

（B）对重复上题。

2.使用式给出的拉普拉斯变换的定义，证明将一幅图像减去其相应拉普拉斯图像等同于对图像做反锐化掩模处理。

3.证明式子的正确性。

4.说明二维正弦函数的傅里叶变换是共轭脉冲对：提示：用式的连续傅里叶变换并以指数项描述正弦。

5.给定的图像，那么一个级金字塔是减少还是增加了表示图像所需的数据量？压缩或扩展率是多少？6.考虑灰度级数据{12，12，13，13，10，13，57，54}的一条8像素的线。

数字图像处理试题及答案

数字图像处理试题及答案一、单项选择题（每题2分，共10分）1. 数字图像处理中，图像的灰度变换不包括以下哪一项？A. 对数变换B. 幂律变换C. 直方图均衡化D. 图像锐化答案：D2. 在数字图像处理中，边缘检测的目的是：A. 提取图像中的纹理信息B. 提取图像中的边缘信息C. 增强图像的对比度D. 改变图像的颜色分布答案：B3. 下列哪种滤波器用于平滑图像？A. 高通滤波器B. 低通滤波器C. 带通滤波器D. 带阻滤波器答案：B4. 在数字图像处理中，图像的几何变换不包括以下哪一项？B. 缩放C. 剪切D. 颜色变换答案：D5. 在数字图像处理中，以下哪种方法用于图像分割？A. 阈值处理B. 边缘检测C. 直方图分析D. 颜色量化答案：A二、多项选择题（每题3分，共15分）6. 数字图像处理中的图像增强技术包括：A. 直方图均衡化B. 锐化C. 噪声滤除D. 图像压缩答案：ABC7. 在数字图像处理中，以下哪些是空间域的图像增强方法？A. 直方图均衡化B. 中值滤波C. 拉普拉斯算子D. 傅里叶变换8. 数字图像处理中，以下哪些是频域的图像增强方法？A. 低通滤波B. 高通滤波C. 带通滤波D. 傅里叶变换答案：ABC9. 在数字图像处理中，以下哪些是图像的几何变换？A. 旋转B. 缩放C. 平移D. 颜色变换答案：ABC10. 数字图像处理中，以下哪些是图像分割的方法？A. 阈值处理B. 边缘检测C. 区域生长D. 颜色量化答案：ABC三、简答题（每题5分，共20分）11. 简述数字图像处理中边缘检测的基本原理。

答案：边缘检测的基本原理是识别图像中亮度变化剧烈的区域，这些区域通常对应于物体的边界。

通过应用边缘检测算子，如Sobel算子、Prewitt算子或Canny算子，可以突出图像中的边缘，从而为后续的图像分析和处理提供重要信息。

12. 描述数字图像处理中直方图均衡化的目的和效果。

答案：直方图均衡化的目的是改善图像的对比度，使图像的直方图分布更加均匀。

大学数字图像处理模拟考试题和答案解析

，（注：以下两套模拟题仅供题型参考，请重点关注选择填空以及判断题、名词解释，蓝色下划线内容肯定不考）《数字图像处理》模拟试卷（A 卷）一、单项选择题（从下列各题四个备选答案中选出一个正确答案，并将其代号填在题前的括号内。

答案选错或未作选择者，该题不得分。

每小题1分，共10分）( d )1.一幅灰度级均匀分布的图象，其灰度范围在[0，255]，则该图象的信息量为：a. 0( b )2.图象与灰度直方图间的对应关系是：a.一一对应b.多对一c.一对多d.都不对…( d )3.下列算法中属于局部处理的是：a.灰度线性变换b.二值化c.傅立叶变换d.中值滤波( b )4.下列算法中属于点处理的是：a.梯度锐化b.二值化c.傅立叶变换d.中值滤波( ) 5.一曲线的方向链码为12345，则曲线的长度为c )6. 下列算法中属于图象平滑处理的是：a.梯度锐化b.直方图均衡c. 中值滤波增强( )7.下列图象边缘检测算子中抗噪性能最好的是：￥a.梯度算子算子算子d. Laplacian算子( c)8.采用模板［-1 1］主要检测____方向的边缘。

a.水平° c.垂直°( d )9.二值图象中分支点的连接数为：( a )10.对一幅100´100像元的图象，若每像元用８bit表示其灰度值，经霍夫曼编码后压缩图象的数据量为40000bit，则图象的压缩比为：:1:1 :1:2二、填空题（每空1分，共15分））1.图像锐化除了在空间域进行外，也可在频率域进行。

2.图像处理中常用的两种邻域是4-邻域和8-邻域。

3.直方图修正法包括直方图均衡和直方图规定化两种方法。

4.常用的灰度差值法有最近邻元法、双线性内插法和三次内插法。

5.多年来建立了许多纹理分析法，这些方法大体可分为和结构分析法两大类。

6.低通滤波法是使高频成分受到抑制而让低频成分顺利通过，从而实现图像平滑。

7.检测边缘的Sobel算子对应的模板形式为和。

数字图像处理模拟题及参考答案

数字图像处理模拟题及参考答案电科08级数字图像处理模拟题及参考答案⼀、填空题1. ⼀般来说，对模拟图像数字化时采样间距越⼤，图像数据越少_,图像质量越_差_______ 2．若灰度图象每像素⽤8位表⽰，则灰度值可以取_0~255 包括0和255间的数值。

3. 在⼏何变换的3×3矩阵___________[p q]______________可以使图像实现平移变换4.⼆值形态学中，腐蚀运算的集合⽅式定义为____}|{XxSxSX?+=Θ____。

5.根据图像编码原理可以将图像编码分为_熵编码__、预测编码、__变换编码__和混合编码6. 图像与灰度直⽅图间的对应关系是_____多对⼀___7. 常⽤的灰度内插法有最近邻域法和 __双线性插值法_。

8.⼀幅图象的分辩率为512×512×8是指_图像的⾼和宽都为512像素，每个像素⽤8位表⽰,该图像⼤⼩约___2048KB9.检测边缘的Sobel算⼦对应的模板形式为_：-1 0 1 -2 0 2 -1 0 1 -1 -2 -10 0 01 2 110．分辩率是⽤来描述图象__清晰程度, ⼀幅图象的分辩率为512×512×8是指_图象宽和⾼都为512象素，每个象素⽤8位表⽰____, 电视摄象机的分辩率为480线是指__⼀副画⾯从上到下扫描⼀遍共有480⾏_________, 激光打印机分辩率为300dpi是指______每英⼨有300个点打印精度。

11.图象直⽅图表⽰：图像上各个灰度级上的像素数⽬。

灰度级01234567像素数33038984532121013.影像数字化包括抽样和量化两过程。

14.图象平滑既可在空间域中进⾏，也可在频率域中进⾏。

边缘检测算⼦对应的模板是：-1-1-1-101000-101111-10117.依据图象的保真度，图象编码可分为⽆失真（⽆损）编码和有失真（有损）编码两种。

18.图像处理中常⽤的两种邻域是 4-邻域和 8—邻域。

Digital Image Processing数字图像处理练习题

一、基本理论与方法1.简要归纳一下傅里叶变换在〈数学图像处理〉的各章节中都有哪些主要应用，应用了它的哪些性质或特点?对下面图像(checkerboard.tif)进行傅氏变换并平移到中心点.(注:先对图像进行灰度格式转换)1）1.图像增强与图像去噪：绝大部分噪音都是图像的高频分量，通过低通滤波器来滤除高频——噪声;边缘也是图像的高频分量，可以通过添加高频分量来增强原始图像的边缘；2.图像分割之边缘检测：提取图像高频分量3.图像特征提取：形状特征：傅里叶描述子纹理特征：直接通过傅里叶系数来计算纹理特征其他特征：将提取的特征值进行傅里叶变换来使特征具有平移、伸缩、旋转不变性4.图像压缩：可以直接通过傅里叶系数来压缩数据；常用的离散余弦变换是傅立叶变换的实变换；5.在图像分析和扫描中，用傅里叶子描述区域边界的二维坐标，在纹理分析中，可以用傅里叶颜谱的频率特性来描述周期的或者几乎周期的二维图像模式的方向性。

（2）步骤：i=imread('checkerboard.tif ');Di=double(i)/255;%将灰度值转成0-1之间的双精度值figure,imshow(Di);fi=fft2(Di);%离散傅氏正变换figure,imshow(fi);ifi=ifft2(fi);%反变换figure,imshow(ifi);变换后：2.先对下图进行二层小波变换(注:先将此图像变为索引图像)然后说明，在图像处理中小波变换的主要用途是什么?(1)小波变换在图像处理中的作用：小波变换没有频域变量，变换后的函数是尺度和位置参数的函数且仍在空域中，其结果是对原函数的位置和尺度的分解。

每一幅小波变换分解图是原函数在位移点的尺度放大或缩小。

是一个时间和频率的局域变换，因而能有效的从信号中提取信息，通过伸缩和平移等运算功能对函数或信号进行多尺度细化分析，解决了傅立叶变换不能解决的许多问题。

它的特点是压缩比高，压缩速度快，压缩后能保持信号与图像的特征不变，且在传递中可以抗干扰。

大学数字图像处理模拟考试题和答案解析

（注：以下两套模拟题仅供题型参考，请重点关注选择填空以及判断题、名词解释，蓝色下划线内容肯定不考）《数字图像处理》模拟试卷（A 卷）一、单项选择题（从下列各题四个备选答案中选出一个正确答案，并将其代号填在题前的括号内。

答案选错或未作选择者，该题不得分。

每小题1分，共10分）( d )1.一幅灰度级均匀分布的图象，其灰度范围在[0，255]，则该图象的信息量为：a. 0b.255c.6d.8( b )2.图象与灰度直方图间的对应关系是：a.一一对应b.多对一c.一对多d.都不对( d )3.下列算法中属于局部处理的是：a.灰度线性变换b.二值化c.傅立叶变换d.中值滤波( b )4.下列算法中属于点处理的是：a.梯度锐化b.二值化c.傅立叶变换d.中值滤波( ) 5.一曲线的方向链码为12345，则曲线的长度为a.5b.4c.5.83d.6.24( c )6. 下列算法中属于图象平滑处理的是：a.梯度锐化b.直方图均衡c. 中值滤波placian增强( )7.下列图象边缘检测算子中抗噪性能最好的是：a.梯度算子b.Prewitt算子c.Roberts算子d. Laplacian算子( c)8.采用模板［-1 1］主要检测____方向的边缘。

a.水平b.45°c.垂直d.135°( d )9.二值图象中分支点的连接数为：a.0b.1c.2d.3( a )10.对一幅100´100像元的图象，若每像元用８bit表示其灰度值，经霍夫曼编码后压缩图象的数据量为40000bit，则图象的压缩比为：a.2:1b.3:1c.4:1d.1:2二、填空题（每空1分，共15分）1.图像锐化除了在空间域进行外，也可在频率域进行。

2.图像处理中常用的两种邻域是4-邻域和8-邻域。

3.直方图修正法包括直方图均衡和直方图规定化两种方法。

4.常用的灰度差值法有最近邻元法、双线性内插法和三次内插法。

图像处理考前复习题双语

同态滤波器 Homomorphic Filters：是一种在频域中同时将图像亮度范围进行压缩和将图像对比度进行增强的方法。 8 什么是伪彩色图像处理？常用的伪彩色图像处理方法有哪些伪彩色图像处理是根据特定的准则对灰度值赋以彩色的处理。密度分割法，灰度级－彩色转换法，频域滤波法。 9 直方图:是灰度级的函数，描述的是图像中具有该灰度级的像素的个数：其横坐标是灰度级，纵坐标是该灰度出现的频率（像素的个数）。性质:1.灰度直方图表征了图像的一维信息 2. 图像与灰度直方图之间是多对一的映射关系 3.子图直方图之和为整图的直方图作用 1．作为图像数字化的参数 2．图像分割阈值的选择依据 3．计算综 contents of digital image processing 数字图像处理的研究内容答：1. Image acquisition 采集 2. Image transform 变换 3. Image enhancement 增强 4. Image Restoration 恢复 5. Image compression 压缩 6. Image Segmentation 分割 7. Image Recognition and Understanding 识别与理解 2 数字图像处理方法有哪些，有何不同？答：空间域处理法和变换域处理法（或称频域法）。空间域指图像平面自身，这类方法是以对图像的像素直接处理为基础的。空域处理法主要有下面两大类：邻域处理法点处理法变换域法：数字图像处理的变换域处理方法是首先对图像进行正交变换，得到变换域系数矩阵，然后再施行各种处理，处理后再反变换到空间域，得到处理结果。 3 数字图像处理中的基本运算有哪些及其应用？点运算 Point Operations：对于一幅输入图像，经过点运算将产生一幅输出图像，输出图像中每个像素点的灰度值仅由相应输入像素点的值决定。点运算有时又被称为对比度增强、对比度拉伸或灰度变换。种类： 1、线性点运算 Linear Point Operations 2、非线性点运算 Nonlinear Monotonic Point Operations。应用 1、对比度增强 2、光度学标定 3、显示标定 4、轮廓线 5、裁剪代数运算 Algebraic Operations 是指对两幅输入图像进行点对点的加、减、乘、除计算而得到输出图像的运算。应用：图像相加，相减，相乘，相除。几何运算 Geometric Operations：几何运算可改变图像中各物体之间的空间关系。应用：几何校正 Geometric Calibration 2、图像配准 Image Registration 4 空间域滤波增强技术中的图像锐化与图像平滑有何区别与联系？答：图象锐化是用于增强边缘，导致高频分量增强，会使图象清晰；图象平滑用于去噪，对图象高频分量即图象边缘会有影响。都属于图象增强，改善图象效果。 5 均值滤波和中值滤波的特点均值滤波器：又称邻域平均滤波器。均值滤波器的概念非常直观。它用滤波掩模确定的邻域内像素的平均灰度值代替图像每个像素点的值。中值滤波器：是一种非线性滤波，它将邻域内所有像素按灰度极进行排序，然后选择中间值作为输出像素值。 6 简述频率域滤波的一般步骤。

数字图像处理(双语)期中考试试卷答案

考试试卷(答案)试卷编号: （）卷课程编号：课程名称：数字图像处理（双语）考试形式：适用班级：姓名：学号：班级：学院: 信息工程学院专业：电子系各专业考试日期:一二三四五六七八九十总分累分人签名题分20 20 20 20 20 0 0 0 0 0 100得分考生注意事项：1、本试卷共5页，请查看试卷中是否有缺页或破损。

如有立即举手报告以便更换。

2、考试结束后，考生不得将试卷、答题纸和草稿纸带出考场。

一、基础知识填空题(1,2为单项选择,每空3分，3,4为多项选择,每空2分,共20分),1 1、When you enter a dark room on a bright day，it takes some time to see wellenough, this is the visual process or visual phenomenon ofA. （Brightness adaptation.）B. （Brightness discrimination。

)C。

（Optical illusion.）D。

(Simultaneous contrast。

）2、The visible spectrum consists of electromagnetic spectrum nearly in therange of wavelength:A。

(10 – 400 nm) B. （0.01 – 10 nm)C。

（400 – 700 nm) D. （700 – 1500nm）3、For V = ｛1｝，the subsets S1 and S2areA。

（m-connected) B。

(8-connected )C. （4-connected)D. （None of these 3）4、Two pixels p and q are at the locations shown in the figure，theirEuclidean，city-block and chessboard distances are respectively：A. D e= （) B。

【数字图像处理】期末复习资料及期末模拟试卷(含答案)doc(DOC)

Digital Image Processing Examination1. Fourier Transform problem.1） F or an image given by the function f(x,y)=(x+y)3 where x,y are continuous varibales; evaluatef(x,y)δ(x-1,y-2) and f(x,y)* δ(x-1,y-2),where δ is the Dorac Delta function.2） F or the optical imaging system shoen below,consisting of an image scaling and two forwardFourier transforms show that the output image is a scale and inverted replica of the original image f(x,y). f(x,y) Scaling f(ax,by) F F g(x,y)_3) three binary images (with value 1 on black areas and value 0 elsewhere) are shown below. Sketch the continuous 2D FT of these images(don’t do this mathematically, try to use instead the convolution theorem and knowledge of FTs of common functions)2. The rate distortion function of a zero memory Gaussian source of arbitary mean and variance σ2 with respect to the mean-square error criterion is⎪⎩⎪⎨⎧≥≤≤=22200log 21)(σσσD D for D D Ra) Plot this functionb) What is D maxc) If a distortion of no mor than 75% of the source’s variance is allowed, what is the maximumcompression that can be achieved?3. The PDF of an image is given by Pr(r) as shown below. Find the transform toconvert the image's PDF to Pr(z). Assume continuity, and find the transform in terms of r and z. Explain the transformation.4. A certain inspection application gathers black & white images of parts as they travel along a con-veyor belt. It is necessary to sort the parts into two categories: parts with holes and parts with-out holes. An example of an image that might be taken by the inspection camera is shown at the right. Propose a method to identify and locate the objects of each category in the image so that they can be picked up by a robotic system and placed in different bins. Assume that the imaging system knows where each image pixel is located on the conveyor belt at every point in time.Provide an annotated flow chart of the algorithm you propose.5.In a given application, an averaging mask is applied to input images to reduce noise and then aLaplacian mask is applied to enhance small details. Would mathematics predict that the result should be the same if the order of the operations were reversed? What practical issues would be encountered in computer implementation?Digital Image Processing Examination1. A preprocessing step in an application of microscopy is concerned with the issue ofisolating individual round particles from similar particles that overlap in groups of two or more.Assuming that all particles are of the same size, propose a morphological algorithm that will produce an image that contains only the isolated (non-overlapping) particles that are not in contact with the boundary of the image.2. An image represented by a continuous function f(x, y) is w = 2 cm wide and h = 3 cm high. The imageis to be converted to an array of pixels by a scanner whose response is zero above 80 lines/centimeter in both the horizontal and vertical directions. The discrete image is represented by an array ˆf(n, m) where n and m take on integer values, 0 ~ n ~ N - 1, 0~ m ~ M-1.(a)Determine suitable values for N and M.(b)Assume that ˆf(n, m) = f(na, mb). Determine the values of a and b.(c)Determine constants A, B, C, D, E such that the DFT of fˆ can be expressed as)(00) ,() , (EvmDuniBnCmemnfAvu F+-==∑∑=(d)Find numbers (P1, P2) such that F(u + jP1, v + kP2) = F(u, v) for any integers j, k, u, v.3. The arithmetic decoding process is the reverse of the encoding procedure. Decode the message 0.23355 given the coding model.4. The gradient of a function f (x) is defined as ⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡∂∂∂∂=⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡=∇y f x f G G f y xComputationally, the first derivative is implemented by calculating the difference between adjacent pixels.(a) Is the following a linear operator?2122⎥⎥⎦⎤⎢⎢⎣⎡⎪⎪⎭⎫ ⎝⎛∂∂+⎪⎭⎫ ⎝⎛∂∂=∇y f x f f (b) State how would you implement the above operator using differences between pixels.(c) A Sobel operator uses two masks, Hx and Hy to process an image. Explain why are two masksneeded and what do they measure?(d) Write down the masks Hx and Hy, and identify them in the followingfigures:5. The three images shown were blurred using square averaging masks of sizes n=23, 25 , and 45, respectively. The vertical bars on the left lower part of (a) and (c) are blurred, but a clear separation exists between them. However, the bars have merged in image (b), in spite of the fact that the mask that produced this image is significantly smaller than the mask that produced image (c). explain this.Digital Image Processing Examination1. An image array f(m, n) of size M1 × N1 is to be convolved with a filter array h(m, n) of size M2 × N2 to produce a new image array g(m, n).1)Write a pseudo code program that describes a method to compute g(m, n) throughthe use of Fourier transforms. The result should be the same size as would beachieved with direct convolution.2)Modify the algorithm so that it does the correlation f ~ h rather than theconvolution.2. You have the job of designing an algorithm that will count the number of objects with holes and the number of objects without holes in images of the kind shown here. Assume that the images are binary with 0 corresponding to black and 1 correspondingto white. The imaging system is of low quality and produces images that are corrupted with salt and pepper noise.The objects do not overlap or touch, but may be close to each other in any direction.They may be of any shape or size. The algorithm should not be confused by the salt and pepper noise, and should not count noise pixels as objects.Write a pseudo-code description of your algorithm. You may also include a block diagram and other information to make it understandable to a programmer. State any assumptions you make, such as: “Objects must contain at least 50 pixels.”least 50 pixels.”3. Suppose that an image has the gray-level probability density functions shown. Here, p 1(z) corresponds to objects and p 2(z) corresponds to the background. Assume that p 1=p 2 and find the optimal threshold between object and back ground pixels.4. The Sobel operator computes the following quantity at each location (x, y) in an image array, A:Gx[j,k]=(A[j+1,k+1]+2A[j+1,k]+A[j+1,k-1])-(A[j-1,k+1]+2A[j-1,k]+A[j-1,k-1]) Gy[j,k]=(A[j-1,k-1]+2A[j,k-1]+A[j+1,k-1])-(A[j-1,k+1]+2A[j,k+1]+A[j+1,k+1]) G[j,k] = |Gx[j,k]| + |Gy[j,k]|The position of A[j, k] is column j and row k of the array.The operation is implemented as the convolution of the image array A with two masks, Mx and My followed by the magnitude operation.1) Write a 3 × 3 array for each mask, Mx and My.2) What mathematical operation on an image array is approximated by the Sobeloperator? Show how the Sobel operator is related to the mathematical operation.5. Answer the following questions about morphological image processing.(a) Shown below are two tables with expressions that relate to binary morphological image processing. Associate each expression in the left table with one from the right table.(b) A well-known morphological algorithm uses the following iteration with a structuring element B.(1) Initialize X[p] = 1 for some pixel A p ∈(2) A B X Y )(⊕=(3) If X Y ≠ then set X = Y and repeat (2)An original set A is shown in (A) and an initial pixel p 2 A is shown in (B). The result after one iteration of the algorithm with structuring element⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡=010111010Bis shown in (C). Fill in the result of the next two iterations by marking theappropriate pixels for the set Y in (D) and (E). In frame (F) show the result for Y that would be reached after a large number of iterations.Digital Image Processing Examination1. Consider the edge model depicted below. Sketch the gradient and Laplacian of the signal. It is not needed to compute exact numerical values in your answer. Plot of approximate shapes of the responses will be sufficient.2. The white bars in the test pattern shown are 7pixels wide and 210 pixels high. The separation between bars is 17 pixels. What would this image look like after application of .1) A 3*3 arithmetic mean filter?2) A 7*7 median filter.3) A 9*9 contraharmonic mean filter with Q=13. The video coding system introduced in the class utilizes several major components –inter-frame motion estimation, motion compensated prediction, DCT, Huffman coding,and quantization.(a)When an encoded signal can be used to reconstruct the exact value of theoriginal signal, we say the encoding method is lossless; otherwise, it’s calledlossy. A lossy coding technique introduces distortion to the signal.Which component in the above video coding system is lossy?(b)The motion compensation process in the encoder generates a motion vectorand prediction errors for each image block in the video signal. Suppose duringthe transmission of the encoded video stream, one motion vector is lost (e.g.,due to the network erasure error). What will be the visual effects of suchtransmission errors on the decoded image sequence?4.Consider a black-and-white image consisting of round and rectangular objects, as shown in the image below. Assume the sizes of the objects are fixed and known. We also know that the width and length of the rectangles are larger than the diameter of the circles. None of the rectangles are tilted. In general, the objects may overlap with each other.Design a morphological operation based system to automatically detect all the instances of the rounds objects that overlap with rectangular objects.5. An image A, represented by an N × M array of bytes, has a uniform brightnesshistogram. It is desired transform A into an image B in a way that produces a triangular brightness histogram2550,36240][≤≤=k k MNk h bDescribe a process that will accomplish the transformation. If possible, derive an equation for the transformation function. At a minimum, sketch the transformation function and indicate how you would use it in a program to compute the array B.模拟试卷一1.对将一个像素宽度的8通路转换到4通路提出一种算法。

数字图像处理模拟题(双语课)

Terms and concepts explanationRGB：Red Green Blue 三原色红绿蓝CMYK：cyan magenta yellow black 青、粉红、黄、黑HSI: hue saturation intensity 色调、饱和度、亮度FFT fast fourier transform 快速傅里叶变换CWT continuous wavelet transform 连续小波变换DCT discrete cosine transform 离散余弦变换DFT discrete fourier transform 离散傅里叶变换DWT discrete wavelet transform 离散小波变换CCD charge-coupled device电荷耦合元件Pixel a digital image is composed of a finite number of elements,each of which has a particular lication and value,these elements are called pixel 像素DC component in frequency domain （direct current component）直流分量的频率域GLH The Gray Level Histogram 灰度直方图Mather（basic）wavelet :a function (wave) used to generate a set of wavelets,母小波，用于产生小波变换所需的一序列子小波Basis functions basis image : there i s only one set of αk for any given f(x), then the ψk (x) are called basis functionsMulti-scale analysis多尺度分析Gaussian function:Gaussian function In mathematics,is a function of the form:for some real constants a 0, b, c 0, and e ≈ 2.718281828 (Euler’s number).对于一些真正的常量0,b,c 0,和e≈2.718281828(欧拉数)。

数字图像处理模拟题答案

谱为基础。空间域图像增强的实现方法主要有基于直方图的均衡化或规定化处理等，还有基于像素点极其邻域的空间域滤波方法（如以统计排序滤波器为代表的平滑空间滤波器和以拉普拉斯掩模为代表的锐化空间滤波器）。而频域图像增强的实现方法是首先把图像变到频域，然后与一系列高通、低通滤波器或同态滤波器等滤波器函数相乘，然后变回空间域（实际过程中前后还要进行中心化处理）。 5、写出图像边缘检测的主要原理，并列举出用来检测边缘的算子。 (10’) 答：图像边缘检测是对于灰度级间断检测的最普遍的方法。一阶导数可以用于检测图像中的一个点是否是边缘点，二阶导数的符号可以用于判断一个边缘像素是在边缘亮的一边还是暗的一边。用局部计算进行处理，使用门限来决定一个值是否有效，若一个点的二维一阶导数比指定的门限大，就定义图像中的此点是一个边缘点，然后依据事先定好的连接准则，将相联系的一组定义为一条边缘。若采用二阶导数，则另一组可用的定义是将图像中的边缘点定义为它的二阶导数的零交叉点。图像中的一阶导数处理用梯度算子，二阶导数使用拉普拉斯算子。常见的梯度算子有 Roberts 算子、 sobel 算子和 Priwitt 算子，其中 Roberts 算子的模板是 2 2 的，由于没有清楚的中心点，所以一般不用，而后两者是在实践中计算数字梯度时最常用的，且 Priwitt 模板实现起来比 sobel 模板更为简单，但后者在噪声抑制特性方面略胜一筹。图像中的二阶导数用拉普拉斯算子计算，但拉普拉斯算子一般不以其原始形式用于边缘检测，而是利用它的零交叉的性质进行边缘定位，或用它确定某个像素是在一条边缘暗的一边还是亮的一边。左图 3 3 区域表示图像领域中的灰度级，则四个算子的表达式为：（亦可用矩阵形式表示） ◎Roberts 算子： G y z8 z 6 Gx z9 z5 ◎ sobel 算子： Gx ( z7 2 z8 z9 ) ( z1 2 z2 z3 ) G y ( z3 2 z6 z9 ) ( z1 2 z4 z7 ) ◎Priwitt 算子： Gy ( z3 z6 z9 ) ( z1 z4 z7 ) Gx ( z7 z8 z9 ) ( z1 z2 z3 ) ◎Laplace 算子： 2 f 4 z5 ( z2 z4 z6 z8 ) 2 f 8 z5 ( z1 z2 z3 z4 z6 z7 z8 z9 )

数字图像处理模拟试卷

《数字图像处理》模拟试卷一、单项选择题（从下列各题四个备选答案中选出一个正确答案，并将其代号填在题前的括号内。

答案选错或未作选择者，该题不得分。

每小题1分，共10分）( )1.一幅灰度级均匀分布的图象，其灰度范围在[0，255]，则该图象的信息量为：a. 0b.255c.6d.8( )2.图象与灰度直方图间的对应关系是：a.一一对应b.多对一c.一对多d.都不对( )3.下列算法中属于局部处理的是：a.灰度线性变换b.二值化c.傅立叶变换d.中值滤波( )4.下列算法中属于点处理的是：a.梯度锐化b.二值化c.傅立叶变换d.中值滤波( ) 5.一曲线的方向链码为12345，则曲线的长度为a.5b.4c.5.83d.6.24( )6. 下列算法中属于图象平滑处理的是：a.梯度锐化b.直方图均衡c. 中值滤波placian增强( )7.下列图象边缘检测算子中抗噪性能最好的是：a.梯度算子b.Prewitt算子c.Roberts算子d. Laplacian算子( )8.采用模板［-1 1］主要检测____方向的边缘。

a.水平b.45°c.垂直d.135°( )9.二值图象中分支点的连接数为：a.0b.1c.2d.3( )10.对一幅100´100像元的图象，若每像元用８bit表示其灰度值，经霍夫曼编码后压缩图象的数据量为40000bit，则图象的压缩比为：a.2:1b.3:1c.4:1d.1:2二、填空题（每空1分，共15分）1.图像锐化除了在空间域进行外，也可在进行。

2.图像处理中常用的两种邻域是和。

3.直方图修正法包括和两种方法。

4.常用的灰度内插法有、和。

5.多年来建立了许多纹理分析法，这些方法大体可分为和结构分析法两大类。

6.低通滤波法是使受到抑制而让顺利通过，从而实现图像平滑。

7.检测边缘的Sobel算子对应的模板形式为和。

8.一般来说，采样间距越大，图象数据量，质量；反之亦然。

数字图像处理模拟题

数字图像处理模拟题1. ⼀幅256*256的图像，若灰度级数为16，则存储它所需的⽐特数是：(A)A、256KB、512KC、1M C、2M提⽰：表达图像所需的⽐特数是图像的长乘宽再乘灰度级数对应的⽐特数。

2. 图像中虚假轮廓的出现就其本质⽽⾔是由于：(A)(平滑区域内灰度应缓慢变化，但当图像的灰度级数不够多时会产⽣阶跃)A、图像的灰度级数不够多造成的；B、图像的空间分辨率不够⾼造成；C、图像的灰度级数过多造成的D、图像的空间分辨率过⾼造成。

3. 在BMP格式、GIF格式、TIFF格式和JPEG格式中：(A)(没有压缩)A、表⽰同⼀副图像，BMP格式使⽤的数据量最多；B、GIF格式独⽴于操作系统；C、每种格式都有⽂件头,其中TIFF格式的最复杂；D、⼀个JPEG格式的数据⽂件中可存放多幅图像。

提⽰：分别考虑这4钟格式的特点。

4. 以下图像技术中属于图像处理技术的是：（AC）（图像合成输⼊是数据，图像分类输出是类别数据）A、图像编码B、图像合成C、图像增强D、图像分类。

提⽰：对⽐较狭义的图像处理技术，输⼊输出都是图像。

5. 如果将图像中对应直⽅图中偶数项的像素灰度均⽤相应的对应直⽅图中奇数项的像素灰度代替，所得到的图像将：（B,C）A、亮度减⼩；B、亮度增加；C、对⽐度减⼩；D、对⽐度增加。

提⽰注意直⽅图中各偶数项⽐对应奇数项⼩1，⽽⼤灰度值对应⾼亮度6. 利⽤平滑滤波器可对图像进⾏低通滤波，消除噪声，但同时模糊了细节。

⼀下哪项措施不能减⼩图像的模糊程度：（C）A、增加对平滑滤波器输出的或值处理（即仅保留⼤于或值的输出）：B、采⽤中值滤波的⽅法；C、采⽤领域平均处理；D、适当减⼩平滑滤波器的领域操作模板。

提⽰：平滑滤波器分为线性滤波器与⾮线性滤波器，处理效果与模板⼤⼩以及⽤模板对像素的处理⽅式有关。

7. 中值滤波器可以：（A,C）A、消除孤⽴噪声；B、检测出边缘；C、平滑孤⽴噪声；D、模糊图像细节。