Pre-trained CNN for one-shot learning I'm currently trying to learn one-shot learning using convolutional neural networks. According to this video, the CNN that I use should have been pre-trained on the MNIST. Why must the CNN be pre-trained??
Because the layers in the CNNs must be already able to extract features from images. 

Normally this procedure takes thousands of iterations to be completed, so if they were not trained we could't have the concept of one-shot learning.