# what is the loss function in char recognition using Tensorflow?

I have code in Tensorflow using convolution neural network to recognize the characters in street view Text (SVT) data.

Since the label type is string, what should I use instead of tf.nn.sparse_softmax_cross_entropy_with_logits() in the loss function?

I cannot use tf.nn.sparse_softmax_cross_entropy_with_logits() because the labels her must be an int dtype??