conv_captcha.py里是只对验证码一个字符进行识别？

[qdk0901]

    # forward prop
    predict = tf.argmax(y_conv, axis=1)
    expect = tf.argmax(y_, axis=1)

    # evaluate accuracy
    with tf.name_scope('evaluate_accuracy'):
        correct_prediction = tf.equal(predict, expect)
        accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))
        variable_summaries(accuracy)

如果要改成识别四个字符的验证码，应该怎么改呢

[JackonYang]

refer to https://github.com/JackonYang/captcha-tensorflow/tree/d0f428524cdc2072d7b192da188a64afc016bbfc#4-char-captcha