Weighted binary cross entropy dice loss for segmentation problem












1















I am using weighted Binary cross entropy Dice loss for a segmentation problem with class imbalance (80 times more black pixels than white pixels) .



def weighted_bce_dice_loss(y_true, y_pred):
y_true = K.cast(y_true, 'float32')
y_pred = K.cast(y_pred, 'float32')
averaged_mask = K.pool2d(
y_true, pool_size=(50, 50), strides=(1, 1), padding='same', pool_mode='avg')
weight = K.ones_like(averaged_mask)
w0 = K.sum(weight)
weight = 5. * K.exp(-5. * K.abs(averaged_mask - 0.5))
w1 = K.sum(weight)
weight *= (w0 / w1)
loss = weighted_bce_loss(y_true, y_pred, weight) + dice_loss(y_true, y_pred)
return loss


Dice coeffecient increased and the loss decreased but at every epoch I am getting a black image as output (all the pixels are labelled black)



enter image description here



Any ideas on why this is happening?










share|improve this question

























  • "Found 60 images belonging to 1 classes"?

    – from keras import michael
    Nov 20 '18 at 5:06











  • It is a segmentation problem. So it is pixelwise binary classification.

    – AKSHAYAA VAIDYANATHAN
    Nov 20 '18 at 6:58











  • What happens if you use a non-Dice weighted cross-entropy (i.e. loss = 'binary_crossentropy' and class_weight = {0: 1 / 81, 1: 80 / 81}?

    – from keras import michael
    Nov 21 '18 at 4:36
















1















I am using weighted Binary cross entropy Dice loss for a segmentation problem with class imbalance (80 times more black pixels than white pixels) .



def weighted_bce_dice_loss(y_true, y_pred):
y_true = K.cast(y_true, 'float32')
y_pred = K.cast(y_pred, 'float32')
averaged_mask = K.pool2d(
y_true, pool_size=(50, 50), strides=(1, 1), padding='same', pool_mode='avg')
weight = K.ones_like(averaged_mask)
w0 = K.sum(weight)
weight = 5. * K.exp(-5. * K.abs(averaged_mask - 0.5))
w1 = K.sum(weight)
weight *= (w0 / w1)
loss = weighted_bce_loss(y_true, y_pred, weight) + dice_loss(y_true, y_pred)
return loss


Dice coeffecient increased and the loss decreased but at every epoch I am getting a black image as output (all the pixels are labelled black)



enter image description here



Any ideas on why this is happening?










share|improve this question

























  • "Found 60 images belonging to 1 classes"?

    – from keras import michael
    Nov 20 '18 at 5:06











  • It is a segmentation problem. So it is pixelwise binary classification.

    – AKSHAYAA VAIDYANATHAN
    Nov 20 '18 at 6:58











  • What happens if you use a non-Dice weighted cross-entropy (i.e. loss = 'binary_crossentropy' and class_weight = {0: 1 / 81, 1: 80 / 81}?

    – from keras import michael
    Nov 21 '18 at 4:36














1












1








1








I am using weighted Binary cross entropy Dice loss for a segmentation problem with class imbalance (80 times more black pixels than white pixels) .



def weighted_bce_dice_loss(y_true, y_pred):
y_true = K.cast(y_true, 'float32')
y_pred = K.cast(y_pred, 'float32')
averaged_mask = K.pool2d(
y_true, pool_size=(50, 50), strides=(1, 1), padding='same', pool_mode='avg')
weight = K.ones_like(averaged_mask)
w0 = K.sum(weight)
weight = 5. * K.exp(-5. * K.abs(averaged_mask - 0.5))
w1 = K.sum(weight)
weight *= (w0 / w1)
loss = weighted_bce_loss(y_true, y_pred, weight) + dice_loss(y_true, y_pred)
return loss


Dice coeffecient increased and the loss decreased but at every epoch I am getting a black image as output (all the pixels are labelled black)



enter image description here



Any ideas on why this is happening?










share|improve this question
















I am using weighted Binary cross entropy Dice loss for a segmentation problem with class imbalance (80 times more black pixels than white pixels) .



def weighted_bce_dice_loss(y_true, y_pred):
y_true = K.cast(y_true, 'float32')
y_pred = K.cast(y_pred, 'float32')
averaged_mask = K.pool2d(
y_true, pool_size=(50, 50), strides=(1, 1), padding='same', pool_mode='avg')
weight = K.ones_like(averaged_mask)
w0 = K.sum(weight)
weight = 5. * K.exp(-5. * K.abs(averaged_mask - 0.5))
w1 = K.sum(weight)
weight *= (w0 / w1)
loss = weighted_bce_loss(y_true, y_pred, weight) + dice_loss(y_true, y_pred)
return loss


Dice coeffecient increased and the loss decreased but at every epoch I am getting a black image as output (all the pixels are labelled black)



enter image description here



Any ideas on why this is happening?







python keras image-segmentation loss cross-entropy






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Nov 19 '18 at 23:33







AKSHAYAA VAIDYANATHAN

















asked Nov 19 '18 at 23:27









AKSHAYAA VAIDYANATHANAKSHAYAA VAIDYANATHAN

40911124




40911124













  • "Found 60 images belonging to 1 classes"?

    – from keras import michael
    Nov 20 '18 at 5:06











  • It is a segmentation problem. So it is pixelwise binary classification.

    – AKSHAYAA VAIDYANATHAN
    Nov 20 '18 at 6:58











  • What happens if you use a non-Dice weighted cross-entropy (i.e. loss = 'binary_crossentropy' and class_weight = {0: 1 / 81, 1: 80 / 81}?

    – from keras import michael
    Nov 21 '18 at 4:36



















  • "Found 60 images belonging to 1 classes"?

    – from keras import michael
    Nov 20 '18 at 5:06











  • It is a segmentation problem. So it is pixelwise binary classification.

    – AKSHAYAA VAIDYANATHAN
    Nov 20 '18 at 6:58











  • What happens if you use a non-Dice weighted cross-entropy (i.e. loss = 'binary_crossentropy' and class_weight = {0: 1 / 81, 1: 80 / 81}?

    – from keras import michael
    Nov 21 '18 at 4:36

















"Found 60 images belonging to 1 classes"?

– from keras import michael
Nov 20 '18 at 5:06





"Found 60 images belonging to 1 classes"?

– from keras import michael
Nov 20 '18 at 5:06













It is a segmentation problem. So it is pixelwise binary classification.

– AKSHAYAA VAIDYANATHAN
Nov 20 '18 at 6:58





It is a segmentation problem. So it is pixelwise binary classification.

– AKSHAYAA VAIDYANATHAN
Nov 20 '18 at 6:58













What happens if you use a non-Dice weighted cross-entropy (i.e. loss = 'binary_crossentropy' and class_weight = {0: 1 / 81, 1: 80 / 81}?

– from keras import michael
Nov 21 '18 at 4:36





What happens if you use a non-Dice weighted cross-entropy (i.e. loss = 'binary_crossentropy' and class_weight = {0: 1 / 81, 1: 80 / 81}?

– from keras import michael
Nov 21 '18 at 4:36












0






active

oldest

votes











Your Answer






StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53384110%2fweighted-binary-cross-entropy-dice-loss-for-segmentation-problem%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes
















draft saved

draft discarded




















































Thanks for contributing an answer to Stack Overflow!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53384110%2fweighted-binary-cross-entropy-dice-loss-for-segmentation-problem%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







這個網誌中的熱門文章

Xamarin.form Move up view when keyboard appear

Post-Redirect-Get with Spring WebFlux and Thymeleaf

Anylogic : not able to use stopDelay()