(segmentation,) partition, grouping and deblending #587
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Hello, can someone please explain what partition, grouping and deblending are? What are the starting and finishing states of these three operations? I am most confused by partitioning, it seems to suggest it sits in the middle of segmentation, grouping and deblending. Thanks! |
Replies: 1 comment · 1 reply
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Hi, In order of processing: Segmentation identifies "islands" of contiguous pixels above the noise threshold as potential sources. Partitioning can then split those islands into several sources (multi-thresholding) , it also removes some that don't have some minimum area. Grouping identifies sources that are close enough to possibly overlap and puts them into a group. The Deblending stage is currently a bit of a misnomer as it takes groups and removes sources in it that are considered to be false detections due to a nearby bright source (cleaning). The model fitting works on groups and fits all the sources in a group so we don't need actual deblending before that. |
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Thankyou! |
Hi,
In order of processing:
Segmentation identifies "islands" of contiguous pixels above the noise threshold as potential sources.
Partitioning can then split those islands into several sources (multi-thresholding) , it also removes some that don't have some minimum area.
Grouping identifies sources that are close enough to possibly overlap and puts them into a group.
The Deblending stage is currently a bit of a misnomer as it takes groups and removes sources in it that are considered to be false detections due to a nearby bright source (cleaning).
The model fitting works on groups and fits all the sources in a group so we don't need actual deblending before that.