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Why does opencv_traincascade not ignore nodes with a false alarm rate of 1

Im using opencv_traincascade with a one stage classifier. I don't really know how it works but it seems like it guesses at rectangles ('features' in CV terminology?) to try and divide the positive samples from the negative sample.
* HR is hit rate - the proportion of positive samples that are (correctly) passed though. * FA is false alarm rate - the proportion of negative samples that are (incorrectly) passed though.

Is my understanding correct?

My output is looks like this:

===== TRAINING 0-stage =====
<BEGIN
POS count : consumed   27 : 27
NEG count : acceptanceRatio    416 : 1
Precalculation time: 3
+----+---------+---------+
|  N |    HR   |    FA   |
+----+---------+---------+
|   1|        1|        1|
+----+---------+---------+
|   2|        1|        1|
+----+---------+---------+
|   3|        1|0.0576923|
+----+---------+---------+
|   4|        1|0.00480769|
+----+---------+---------+
END>

Why does it not ignore feature/node/rectangle number 1 and number 2 since they appear to simply let though everything?

Why does opencv_traincascade not ignore nodes with a false alarm rate of 1

Im using opencv_traincascade with a one stage classifier. I don't really know how it works but it seems like it guesses at rectangles ('features' in CV terminology?) to try and divide the positive samples from the negative sample.
*

  • HR is hit rate - the proportion of positive samples that are (correctly) passed though. * though.
  • FA is false alarm rate - the proportion of negative samples that are (incorrectly) passed though.

Is my understanding correct?

My output is looks like this:

===== TRAINING 0-stage =====
<BEGIN
POS count : consumed   27 : 27
NEG count : acceptanceRatio    416 : 1
Precalculation time: 3
+----+---------+---------+
|  N |    HR   |    FA   |
+----+---------+---------+
|   1|        1|        1|
+----+---------+---------+
|   2|        1|        1|
+----+---------+---------+
|   3|        1|0.0576923|
+----+---------+---------+
|   4|        1|0.00480769|
+----+---------+---------+
END>

Why does it not ignore feature/node/rectangle number 1 and number 2 since they appear to simply let though everything?