After studying this chapter you will be able to understand: The global information of the image with the help of histogram, histogram based techniques, histogram equalization, histogram specification or also known as histogram matching or histogram modification. | Digital Image Processing CSC331 Image Enhancement 1 Summery of previous lecture Necessity of image enhancement. Image enhancement techniques broad categories. 1: spatial domain operations 2: Frequency domain operations point processing Threshold operation Mask operation Negative image Low Contrast image reducing dynamic range Power law transformation Gray level slicing 2 Todays lecture The global information of the image with the help of histogram Histogram based techniques, Histogram equalization Histogram specification or also known as histogram matching or histogram modification 3 4 Dark image 5 Bright Image 6 Low contrast image 7 8 Histogram give us a global appearance of that particular image histogram based techniques to modify the image Histogram equalization operation Histogram modification operation How these histograms can be processed to enhance the images? 9 10 11 12 13 Histogram equalization 14 Histogram equalization 15 Limitation of Histogram equalization whatever image the equalized image you get that is fixed. No interactive manipulation of the image. For some certain region of the histogram, enhancement the we need histogram matching or histogram specification techniques. 16 17 18 Histogram specification 19 Histogram specification 20 look of tables implementation 21 22 Summery of the lecture The global information of the image with the help of histogram Histogram based techniques, Histogram equalization Histogram specification or also known as histogram matching or histogram modification 23 References Prof .P. K. Biswas Department of Electronics and Electrical Communication Engineering Indian Institute of Technology, Kharagpur Gonzalez R. C. & Woods . (2008). Digital Image Processing. Prentice Hall. Forsyth, D. A. & Ponce, J. (2011).Computer Vision: A Modern Approach. Pearson Education. . | Digital Image Processing CSC331 Image Enhancement 1 Summery of previous lecture Necessity of image enhancement. Image enhancement techniques broad categories. 1: spatial domain operations 2: Frequency domain operations point processing Threshold operation Mask operation Negative image Low Contrast image reducing dynamic range Power law transformation Gray level slicing 2 Todays lecture The global information of the image with the help of histogram Histogram based techniques, Histogram equalization Histogram specification or also known as histogram matching or histogram modification 3 4 Dark image 5 Bright Image 6 Low contrast image 7 8 Histogram give us a global appearance of that particular image histogram based techniques to modify the image Histogram equalization operation Histogram modification operation How these histograms can be processed to enhance the images? 9 10 11 12 13 Histogram equalization 14 Histogram equalization 15 Limitation of Histogram equalization whatever image the equalized image you get that is fixed. No interactive manipulation of the image. For some certain region of the histogram, enhancement the we need histogram matching or histogram specification techniques. 16 17 18 Histogram specification 19 Histogram specification 20 look of tables implementation 21 22 Summery of the lecture The global information of the image with the help of histogram Histogram based techniques, Histogram equalization Histogram specification or also known as histogram matching or histogram modification 23 References Prof .P. K. Biswas Department of Electronics and Electrical Communication Engineering Indian Institute of Technology, Kharagpur Gonzalez R. C. & Woods . (2008). Digital Image Processing. Prentice Hall. Forsyth, D. A. & Ponce, J. (2011).Computer Vision: A Modern Approach. Pearson Education. 24
