pointnet_seg.py 文件源码

def get_loss(pred, label, end_points, reg_weight=0.001):
    """ pred: BxNxC,
        label: BxN, """
    loss = tf.nn.sparse_softmax_cross_entropy_with_logits(logits=pred, labels=label)
    classify_loss = tf.reduce_mean(loss)
    tf.scalar_summary('classify loss', classify_loss)

    # Enforce the transformation as orthogonal matrix
    transform = end_points['transform'] # BxKxK
    K = transform.get_shape()[1].value
    mat_diff = tf.matmul(transform, tf.transpose(transform, perm=[0,2,1]))
    mat_diff -= tf.constant(np.eye(K), dtype=tf.float32)
    mat_diff_loss = tf.nn.l2_loss(mat_diff) 
    tf.scalar_summary('mat_loss', mat_diff_loss)

    return classify_loss + mat_diff_loss * reg_weight