If I understand correctly, the question is, given many images which are result of different Edge Filter applied on the same image, how to actually mark edges.
Well, you basically created 25 tests for each pixel to decide whether or not it is an edge.
You could apply many approaches to decide:
- Majority Votes - If more than half of the voters decided it is an edge, nark it as an edge.
- Threshold - If more than $ x $ voters vote for edge the pixel will be declared as an edge.
- Spatial Model - Instead of per pixel decision, look around it and other voters.
- Weight of Votes - Don't mark votes as "Yes / No" but give it a scalar. If the sum of all scalars above a threshold value, declare an edge.
As you can see the options are endless.