machine_vision_b.py 文件源码

def create_left_right(c, w): 
  #tanget vectors
  c_shape = c.get_shape().as_list();
  c1 = tf.slice(c, [1,0], [-1,-1]);
  c2 = tf.slice(c, [0,0], [c_shape[0]-1,-1]);
  dc = tf.sub(c1,c2);

  #normalized tangent vectors
  nr = tf.sqrt(tf.reduce_sum(tf.square(dc), reduction_indices = 1));
  dcn = tf.transpose(tf.div(tf.transpose(dc), nr));

  #average tangent
  dc1 = tf.concat(0, [tf.slice(dcn, [0,0], [1,-1]), dcn]);
  dc2 = tf.concat(0, [dcn, tf.slice(dcn, [c_shape[0]-2,0], [1,-1])]);
  av = tf.scalar_mul(0.5, tf.add(dc1,dc2));
  nr = tf.sqrt(tf.reduce_sum(tf.square(av), reduction_indices = 1));
  av = tf.transpose(tf.div(tf.transpose(av), nr));

  #normal
  nrm = tf.mul(av, tf.constant([-1,1], "float32"));
  nrm = tf.reverse(nrm, [False, True]);

  left = tf.transpose(tf.mul(tf.transpose(nrm), w));
  right= tf.scalar_mul(-1.0, left);

  left = tf.add(left, c);
  right= tf.add(right,c);

  return left,right