1. Digital Image Processing Lecture - 6 Autumn 2009

2. Images and Their Histograms

3. Before Histogram Equalization

4. Result of Histogram Equalization

5. Transformation Curves

6. Histogram Matching ► Objective:  Enhance the image such that it has desired histogram (after enhancement)  Inputs for histogram matching ► Input image ► Specified histogram

7. Histogram Equalization Example

9. Histogram Matching

17. Filtering in Spatial Domain

20. Filter Mask

21. Smoothing Filter

23. Diminishing Small Objects

24. Non Linear Smoothing Filters

25. Sharpening Filters: Derivative Operators

27. Laplacian Operator

28. Sharpening the Image

29. Un-Sharp Masking

30. Hi-Boost Filtering

31. Un-sharp Masking vs Hi-boost Filtering

32. 1 st Order Derivative

33. Combining Spatial Enhancement Methods