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### HOG detection clarification

Hello, i am new to Computer vision and Machine learning, i searched a lot but did not find an answer for my questions.

First: I want to know what is the difference between all of these detection methods.

1)HOG.detect()

2)HOG.detectMultiScale()

3)HOG.setSvmDetector()

Second: I read that HOG.setSvmDetector() used only for detecting one object since SVM is a binary classfication, i was wondering can we train multi class SVM (One vs All) and for each single class of SVM we apply a new instance of HOG.setSvmDetector() ?

for an examlpe if i constructed 2 SVM's which means now i have Multi class SVM of 2 classes can i do smth like this:

HOGDescriptor hog1 = newHOGDescriptor()

HOGDescriptor hog2 = new HOGDescriptor()

HOG.setSvmDetector( CLASS ONE )

HOG.setSvmDetector( CLASS TWO )