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Rekognition search faces API endpoint


Hi everyone!

Currently, I've accomplished detecting all the faces from a collection and then generating sub-galleries of each subject with all their photos associated with the ruby SDK '~> 1.65'

To do this, I've indexed the faces of all photos within a collection, list all the faces (, then grabbing each face_id recognized and search the faces related to that face_id (, and delete the face id used to do the API call and all the returned ones to tell when a new detected subject starts and ends.

My issue is that the search faces API returns different results depending on which face id param you are doing the request with. For example, if there are 10 faces ids detected that belong to a person (1, 2, 3, ..., 10), the search faces call with face id = 1 param, should return the faces id (2, 3, 4, ..., 10) but if you continue to do this with the other face ids this is not always the case with some scenarios where the search faces call with face id = 3 has returned a subset of the previously mentioned like just (4, 5, 6).

Is there any other way to achieve this to prevent this kind of "error"? if not, this is a real concern for us because it depends on the order in which we call the search faces with different face ids, and sometimes it seems like there is more than 1 subject detected with almost the same photos when in reality it's the same person.

Thanks in advance!

3 Answers

Hi, thanks for your reply!

All the mentioned above happened with the matching threshold set to 90%, but even after I've changed it to 95% it keeps behaving the same way

answered 5 months ago
  • Also no change when the threshold is under 80% ? Perhaps the similarity between some faces is under the default threshold


Hello, did you notice any correlation with the face matching threshold ? By default it's 80%

answered 5 months ago

Hi, we are happy to work with you to investigate this issue. Can you open a case using this link and share the case ID here. We can then engage directly to troubleshoot.

answered 5 months ago

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