Digital image processing- previous year question paperDigital image processing

Part A1. define 4 and 8 neighbours of a pixels2. what are separable image transforms?3. define histogram4. name the different types of derivatives filters5. define averaging filters6. give the difference between enhancement and restoration7. define compression ratio8. what are the basic steps in JPEG?9. show that the average value of the laplacian operator is zero10. define the chain code derivative in 4 and 8 connectivity Part B11.a. explain discrete cosine transform and its properitiesOr(b)explain in detail how the continuous image can be converted into digital image using suitabletechnique12 (a)explain histogram and give its equalizationOr(b)discuss in detail the homomorphic and derivative filters13(a)(i)explain mean filter in detail(ii)explain the operation of inverse filteringOr(b)explain adaptive filter and also what are the two levels of adaptive median filteringalgorithms.14(a)explain with block diagram the lossless precitive codingOr(b) explain with block diagram the lossy precitive coding with delta modulation technique15(a)illustrate with suitable examples how are gradient operators used for detection of edges in medical imagesOr(b)show that how hough transforms can be used to link edges1 (a) Define and discuss following terms :(i) Gray level (ii) Gray scale(b) Explain about imaging geometry.2 Explain following 2D-transforms.(i) 2D- Hadamard (ii) Slant transform(iii) Hotelling transform3 Discuss following histogram techniques for image enhancement.(a) Histogram specification(b) Local enhancement4 Explain any three filters which are using for image smoothing in both spatial domain and frequency domain5 (a) Explain about color models.(b) Explain intensity slicing in pseudo color image processing.6 Explain(a) Inverse filtering(b) Weiner filtering

7 Explain edge linking and Boundary detection of segmentation.8 (a) What is image Compression? Explain about coding redundancy?(b) What is Huffman coding explain by taking an example

SRM UNIVERSITYFaculty of Engineering and TechnologySchool of Electronics and Communication Engineering

Question BankSubject Code : EC455Subject Name : Digital Image ProcessingClass & Sem : IV Year B.Tech(ECE), VII Sem

UNIT-IPART-A1. Draw the cross section of the human eye.2. Explain- photopic or bright-light vision.3. Explain-scotopic or dim-light vision.4. What is called blind spot in the eye?5. The observer is looking at a tree 15m high at a distance of 100m. Find the size of the retinal image.6. Define Weber ratio.7. Explain image formation in the eye.8. What is brightness adaptation?9. What is brightness discrimination?10. What is Mach band pattern?11. Explain simultaneous contrast.12. How a digital image is represented?13. What do you mean by a pixel?14. What are called 4-neighbors of a pixel?15. What are diagonal neighbors of a pixel?16. Define 4-connectivity.17. Define 8-connectivity.18. Define m-connectivity.19. What is called Euclidean distance?20. What is called D4 distance or city-block distance? 21. What is called D8 distance or chess board distance?22. Give any four arithmetic operators with pixels.23. Give any four logical operators with pixels.24. What is meant by perspective transformation?25. What is called camera calibration?.26. What do you mean by stereo imaging?27. What is called gray scale?

PART-B1. Explain in detail the elements of Digital Image Processing systems.2. Explain in detail the structure of the human eye.3. Explain image formation in the eye, brightness adaptation and

discrimination.4. Explain any four basic relationships between pixels.5. Using perspective transformation and assuming the world coordinate system is aligned with the camera coordinate system, derive expression for x,y,z.6. Using perspective transformation and assuming the world coordinate system is aligned with the camera coordinate system, derive expression for X,Y,Z.7. Explain the basic transformations: translation, scaling, rotation, concatenation and inverse transformation.

UNIT-IIPART-A1. Define a two dimensional bandlimited image.2. Define Nyquist rate.3. What is aliasing? Explain it with image spectrum.4. What are called fold over frequencies?5. Define sampling theorem.6. List the practical limitations in sampling and reconstruction.7. What is Moiré effect?8. Write a note on display aperture.9. What is quantization? How it is applied in images?10. List the properties of the optimum mean square Quantizer.11. What will be the mean square error for uniform PDF Optimal Quantizer?12. What is meant by visual quantization?13. How to reduce the contouring effect in visual quantization?14. Draw the block diagram of Contrast quantization.15. Draw the block diagram of pseudo random noise quantization.16. What is a compandor?

PART-B1. Explain 2-D sampling theory in detail.2. Explain in detail the practical limitations in sampling and reconstruction.3. Explain the optimum mean square or Lloyd-max quantizer in detail.4. Explain in detail about visual quantization.5. Explain the process of reconstruction of an image from its samples.6. Explain compandor design.

UNIT –IIIPart – A1) Properties of Fourier Transform?2) Write the equation for 2D Fourier transform and Inverse Fourier transform?3) Write the equation for the 2-D convolution?4) Properties of convolution?5) Define orthogonal matrix and unitary matrix?

6) Consider the matrices 

Check that A1 is orthogonal & unitary, A2 is not unitary, A3 is unitary with orthogonal rows.

7) If A and B are M1 xM2 and N1 xN2 matrices respectively, find their Kronecker product.8) Define Kronecker Product?9) If . Find their kronecker product.10) Define the mean and co-variance of random signal?11) For a given orthogonal matrix A and image U, Find the transformed image and the inverse transformation.12) Write the equation for the 2-D orthogonal and unitary transforms?13) Give some properties of 2-D DFT?14) Write the equation for 2-D IDFT?15) Mention the properties of Discrete cosine transform.16) Define DCT?17) Define Sequency?18) Properties of Hadamard Transform?19) For the 2x2 transform A and the image U

Calculate the transformed image V and the basis images.20) What is Walsh transform?21) Give some properties of 2-dimensional DFT?22) What are the properties of walsh transform?23) What is Haar Transform?24) What is Hadamard transform?25) Write the properties of Haar transform?26) What is slant transform?27) What are the properties of slant transform?28) What is KL transform?29) What are the properties of KL transform?30) Compare KL, Hadamard, Haar and slant transform?

PART – B1) Find the Fourier spectrum , phase angle and power spectrum of 2D Fourier transform.2) Write the DFT for the 2-variable? Find the DFT for the following sequence {2,3,4,4} and find its fourier spectrum?3) Explain the following DFT properties:a) Separability b) Translationc) Rotation d) Distributivity & scaling4) Explain the following (a) Convolution (b) Correlation5) Develop an FFT algorithm for a 2-D transform? How many additions & multiplication are needed to compute 2D FFT of an N x N image?6) Obtain the Haar transform matrix for N=4?7) Obtain the Haar transform matrix for N=8?

8) Obtain the slant transform matrix for N=4?9) Obtain the slant transform matrix for N=8?10) Obtain the Hadamard transform matrix for N=4?11) Obtain the Hadamard transform for N=8?12) Obtain the Walsh transform matrix for N=4?

UNIT – IVPart- A1. What is image enhancement? What are the types of enhancement available?2. What is point processing?3. What is contrast stretching? Why is it required?4. What is the need for reducing the dynamic range of image?5. What is gray level slicing?6. What is bit plane slicing?7. What is histogram?8. What is histogram equalization?9. Draw the histogram for bright image and low contrast image?10. Give the steps in histogram specification?11. What is spatial filtering?12. What are the effects of low pass and high pass filtering of images?13. What is image smoothening? What are the types available?14. Explain high boost filtering.15. Draw the mask for different derivative filters.16. What is homomorphic filtering?17. Differentiate restoration and enhancement.18. What is circulant and block-circulant matrices.19. What is meant by diagonalization? Why is it required?20. What is meant by algebraic approach to restoration? What are the types?21. What is constrained and unconstrained restoration?22. What is inverse filtering?23. Write the equation for wiener filter.24. What is parametric wiener filter?25. What is rubber sheet transformation?26. What are the basic operations in geometric transformation?27. What is Gray- level interpolation?

Part –B1) Explain the different point processing techniques used for image enhancement.2) With neat diagram histogram processing and Equalization.3) Explain histogram specification.4) Explain the various types of image smoothening filters.5) Explain in detail about homomorphic filtering.6) Explain the concept of degradation model.7) Explain discrete formulation of degradation model.8) Describe the process involved in diagonalisation of circulant and block

circulant matrices.9) Explain constrained and unconstrained algebraic approach in detail.10) Explain inverse filtering in detail.11) Explain weiner filter in detail.12) Write notes on Geometric transformation.

Unit VPart A1. What is data redundancy?2. What is coding redundancy?3. What is variable length coding.4. What is psychovisual redundancy?5. Define distance b/w two codewords.6. What is the distance between codewords 101101 & 0111017. Define information of a random event E 8. What is BSC9. State Shannon’s channel capacity theorem.10. What is blocking artifact?11. What is bit allocation?12. What is a zonal mask.13. What are the types of discontinuities in a digital image.14. What is global thresholding15. What is local thresholding16. What is dynamic thresholding17. What is the purpose of image segmentation?18. Give the 3x3 prewitt mask.19. Draw the 3x3 sobel mask.20. What is run length coding?21. What is direct contour tracing?22. Define rate distortion function.23. What is channel matrix?24. Define mutual information.25. Mention any two variable length coding techniques.

Part B1. Explain improved gray-scale quantization.2. Explain the fidelity criteria used for assessment of images.3. Explain with a neat block diagram a general compression system model.4. Explain with block diagrams, the source encoder & source decoder used in image compression.5. Explain briefly about channel encoder & channel decoder used in image compression.6. Define (a) Entropy of source (b) Conditional entropy(c) Mutual information. (d) Binary symmetric channel.7. Explain in detail the rate distortion theory.8. Explain Huffman coding with an example.9. For the symbols a,b,c,d,e,f the respective probabilities are p(a)=0.1,

p(b)=0.4, p(c)=0.06, p(d)=0.1, p(e)=0.04, p(f)=0.3.(a) What is average length of the code.(b) What is the Huffman code efficiency.10. Explain constant area coding.11. Explain with a neat block diagram, the lossy predictive coding model .12. What is transform coding? Explain with a neat diagram.13. Explain zonal coding?14. Explain briefly about threshold coding.15. Explain point detection & line detection.16. Explain the process of edge detection using gradient operators.17. Explain edge detection using laplacian operator. 18. What is thresholding? Explain in detail.19. Explain region growing by pixel aggregation20. Explain edge linking using hough transform.