Features from images using opencv in Python I want to start   with  image processing (image classification).
I installed  opencv  and plan  to use it    with Python.
Being starter  at   this, I am looking   for references   regarding  trivial  issues like:
I just  saved some images  and  want to  get their pixel  values  as  features ,  hoewever   when I try loading it  in opencv,  I am    getting differently  shaped   3-dimmensional  objects.
Some   references   or suggestion regarding this   issue  will be highly  appreciated.
Your numpy arrays are 3-dimensional because they are colored images. The first dimension is the y-dimension, the second dimension is your x-dimension and the third dimension is the different color channels. What order they are in depends on your reader, but I think OpenCV uses BGR (check the documentation here). A lot of the feature extraction methods only work on grayscale arrays which are mapped back to two dimensions, any of the well known image packages can do this for you (OpenCV, scikit-image).