updating messages

updating messages

Student (guest) 22 Apr 2017 14:43

Hi, I didn't completely understand how to update the messages.
I understand from the instruction that we need to go over all unobserved nodes and update all the out-going messages from them to their observed neighbors.
All the in-going messages to the unobserved nodes are simply the pairwise function where the "from" node is an observed pixel and the "to" node is the optional value of the unobserved node.
However this way the in-going messages are never updated, and the approximate assignment is dependent only on the in-going messages of the unobserved nodes.
How are the in-going messages updated? How do we use the updated out-going messages to approximate unobserved pixels?
Thanks

amir (guest) 23 Apr 2017 08:22

The unobserved pixels have ingoing messages from both observed and unobserved nodes. So, as you iterate, the messages from the unobserved nodes will change. As you say, the messages from the observed nodes will not change, so they keep sending the same thing to the unobserved ones.