title: How filters are initialized in convnet
body: <p>I read a lot of papers on convnets, but there is one thing I don't understand, how the filters in convolutional layer are initialized ?
  Because, for examples, in first layer, filters should detect edges etc..
  But if it randomly init, it could not be accurate ? Same for next layer and high-level features.
  And an other question, what are the range of the value in those filters ?</p>
  
  <p>Many thanks to you!</p>