04-06-2012, 11:37 AM
Digital Image Processing
ImageProcessing8-Imagerestoration.ppt (Size: 3.44 MB / Downloads: 234)
What is Image Restoration?
Image restoration attempts to restore images that have been degraded
Identify the degradation process and attempt to reverse it
Similar to image enhancement, but more objective
Noise and Images
The sources of noise in digital images arise during image acquisition (digitization) and transmission
Imaging sensors can be affected by ambient conditions
Interference can be added to an image during transmission
Noise Example
The test pattern to the right is ideal for demonstrating the addition of noise
The following slides will show the result of adding noise based on various models to this image
Filtering to Remove Noise
We can use spatial filters of different kinds to remove different kinds of noise
The arithmetic mean filter is a very simple one and is calculated as follows:
Band Reject Filters
Removing periodic noise form an image involves removing a particular range of frequencies from that image
Band reject filters can be used for this purpose
An ideal band reject filter is given as follows:
ImageProcessing8-Imagerestoration.ppt (Size: 3.44 MB / Downloads: 234)
What is Image Restoration?
Image restoration attempts to restore images that have been degraded
Identify the degradation process and attempt to reverse it
Similar to image enhancement, but more objective
Noise and Images
The sources of noise in digital images arise during image acquisition (digitization) and transmission
Imaging sensors can be affected by ambient conditions
Interference can be added to an image during transmission
Noise Example
The test pattern to the right is ideal for demonstrating the addition of noise
The following slides will show the result of adding noise based on various models to this image
Filtering to Remove Noise
We can use spatial filters of different kinds to remove different kinds of noise
The arithmetic mean filter is a very simple one and is calculated as follows:
Band Reject Filters
Removing periodic noise form an image involves removing a particular range of frequencies from that image
Band reject filters can be used for this purpose
An ideal band reject filter is given as follows: