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Krisch Compass Mask

Kirsch compass mask is used for finding edges. It is almost the same as Robinson compass mask. It also has 8 direction compass. The main difference between Robinson and kirsch compass masks is that in kirsch we can change the mask according to the requirements.

Following are its eight orientations:

• North
• North West
• West
• South West
• South
• South East
• East
• North East

Standard size is taken and then it is rotated in all directions.

Following is a mask which is in north direction and the rotated:

North

North West

West

South West

South

South East

East

North East

Example of Kirsch compass mask applied to an image

Original image

The maximum gradient in the 8 directions

North

North West

West

South West

South

South East

East

North East

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