训练数据和词汇之间的差异-单词袋

Question

When creating a Bag Of Words, you need to create a Vocabulary to give to the BOWImgDescriptorExtractor to which you use on the images you wish to input. This creates the Testing Data .

So where does the Training Data come from, and where do you use it?

Whats the difference between Vocabulary and Training Data ?

Isn't the Vocabulary the same thing as the Training Data ?

Answer 1

Training data is a set of images you collected for your application as the input of BOWTrainer , and vocabulary is the output of the BOWTrainer . Once you have the vocabulary , you can extract features of images using BOWImgDescriptorExtractor with the words defined in the vocabulary .

An image can be described by tons of features ( words ), however only some of them are important. The first job to do is to find those important words , that is, to train a vocabulary . After the vocabulary is obtained, images can be described more precisely.

So where does the Training Data come from, and where do you use it?

You should provide the Training data , and use it to train the vocabulary with BOWTrainer . The Training data is a set of images (descriptors), depends on your application domain.

What's the difference between Vocabulary and Training Data ?

Vocabulary is cooked, while training data is raw, unorganized.

Isn't the Vocabulary the same thing as the Training Data ?

No.

Answer 2

There is an add function that is used to specify training data. docs on opencv bow module