The document discusses various image enhancement techniques in Matlab, including filtering, predefined filters, image enhancement tools, image restoration, dilation/erosion functions, and dithering. Filtering can be used to modify images through operations like smoothing, sharpening, and edge enhancement. Predefined filters like 'gaussian' and 'laplacian' can be applied to images with functions like fspecial and imfilter. Additional tools for operations such as histogram equalization, noise addition, and filtering are also covered.

1. Matlab:Image enhancement techniques

2. FilteringFiltering is a technique for modifying or enhancing an image. Image processing operations implemented with filtering include smoothing, sharpening, and edge enhancement.

3. Filtering an Image with Predefined Filter TypesThe ‘fspecial’ function produces several kinds of predefined filters. After creating a filter with ‘fspecial’, we can apply it directly to our image data using ‘imfilter’.I = imread('moon.tif');

4. h = fspecial('unsharp');

5. I2 = imfilter(I,h);

6. imshow(I), title('Original Image')

7. figure, imshow(I2), title('Filtered Image')Filtering an Image with Predefined Filter Types

8. Filtering an Image with Predefined Filter TypesPredefined filters provided by ‘fspecial’

9. average’ Averaging filter

10. 'disk’ Circular averaging filter (pillbox)

11. 'gaussian’ Gaussian lowpass filter

12. 'laplacian’ Approximates the two-dimensional Laplacian operator