377989c11903f69f042fee717ce6be66bd6eb43a,niftynet/layer/loss_segmentation.py,,generalised_dice_loss,#,120

Before Change

    :return: the loss
    
    ground_truth = tf.to_int64(ground_truth)
    n_voxels = ground_truth.shape[0].value
    n_classes = prediction.shape[1].value
    ids = tf.constant(np.arange(n_voxels), dtype=tf.int64)
    ids = tf.stack([ids, ground_truth], axis=1)
    one_hot = tf.SparseTensor(indices=ids,
                              values=tf.ones([n_voxels], dtype=tf.float32),
                              dense_shape=[n_voxels, n_classes])

    if weight_map is not None:
        weight_map_nclasses = tf.reshape(
            tf.tile(weight_map, [n_classes]), prediction.get_shape())
        ref_vol = tf.sparse_reduce_sum(
            weight_map_nclasses * one_hot, reduction_axes=[0])

        intersect = tf.sparse_reduce_sum(
            weight_map_nclasses * one_hot * prediction, reduction_axes=[0])
        seg_vol = tf.reduce_sum(
            tf.multiply(weight_map_nclasses, prediction), 0)
    else:
        ref_vol = tf.sparse_reduce_sum(one_hot, reduction_axes=[0])
        intersect = tf.sparse_reduce_sum(one_hot * prediction,
                                         reduction_axes=[0])
        seg_vol = tf.reduce_sum(prediction, 0)
    if type_weight == "Square":
        weights = tf.reciprocal(tf.square(ref_vol))
    elif type_weight == "Simple":
        weights = tf.reciprocal(ref_vol)
    elif type_weight == "Uniform":
        weights = tf.ones_like(ref_vol)
    else:
        raise ValueError("The variable type_weight \"{}\""
                         "is not defined.".format(type_weight))
    new_weights = tf.where(tf.is_inf(weights), tf.zeros_like(weights), weights)
    weights = tf.where(tf.is_inf(weights), tf.ones_like(weights) *
                       tf.reduce_max(new_weights), weights)
    generalised_dice_numerator = \
        2 * tf.reduce_sum(tf.multiply(weights, intersect))
    generalised_dice_denominator = \
        tf.reduce_sum(tf.multiply(weights, seg_vol + ref_vol))
    generalised_dice_score = \
        generalised_dice_numerator / generalised_dice_denominator
    return 1 - generalised_dice_score

After Change

        Simple (inverse of volume) and Uniform (no weighting))
    :return: the loss
    
    prediction = tf.cast(prediction, tf.float32)
    one_hot = labels_to_one_hot(ground_truth, tf.shape(prediction))
    n_classes = prediction.shape[1].value

    if weight_map is not None:
        weight_map_nclasses = tf.reshape(
            tf.tile(weight_map, [n_classes]), prediction.get_shape())
        ref_vol = tf.sparse_reduce_sum(
            weight_map_nclasses * one_hot, reduction_axes=[0])

        intersect = tf.sparse_reduce_sum(
            weight_map_nclasses * one_hot * prediction, reduction_axes=[0])
        seg_vol = tf.reduce_sum(
            tf.multiply(weight_map_nclasses, prediction), 0)
    else:
        ref_vol = tf.sparse_reduce_sum(one_hot, reduction_axes=[0])
        intersect = tf.sparse_reduce_sum(one_hot * prediction,
                                         reduction_axes=[0])
        seg_vol = tf.reduce_sum(prediction, 0)
    if type_weight == "Square":
        weights = tf.reciprocal(tf.square(ref_vol))
    elif type_weight == "Simple":
        weights = tf.reciprocal(ref_vol)
    elif type_weight == "Uniform":
        weights = tf.ones_like(ref_vol)
    else:
        raise ValueError("The variable type_weight \"{}\""
                         "is not defined.".format(type_weight))
    new_weights = tf.where(tf.is_inf(weights), tf.zeros_like(weights), weights)
    weights = tf.where(tf.is_inf(weights), tf.ones_like(weights) *
                       tf.reduce_max(new_weights), weights)
    generalised_dice_numerator = \
        2 * tf.reduce_sum(tf.multiply(weights, intersect))
    generalised_dice_denominator = \
        tf.reduce_sum(tf.multiply(weights, seg_vol + ref_vol))
    generalised_dice_score = \
        generalised_dice_numerator / generalised_dice_denominator
    return 1 - generalised_dice_score

Instances