Data Science Stack Exchange
Data Science Stack Exchange

Questions tagged [semantic-segmentation]

52 questions
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2 answers

What is Deep supervision?

I'm interested in segmentation models for medical imaging purposes. When I looked at the state of the art, I fell on a paper on a new architecture, Unet++: UNet++: A Nested U-Net Architecture for Medical Image Segmentation from Zongwei Zhou, Md…
Nicolas
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4
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Tool for annotation of images for semantic segmentation

I have been searching around for a software tool, that I can use for annotating images. More specifically I want to do annotation to be used for semantic segmentation, meaning I want to create masks. I want to be able to create training data for…
lo2
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What is the difference in computational cost at inference time between object detection and semantic segmentation?

I am aware that YOLO (v1-5) is a real-time object detection model with moderately good overall prediction performance. I know that UNet and variants are efficient semantic segmentation models that are also fast and have good prediction…
JStrahl
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Image segmentation with large class imbalance leads to zero precision/recall

I have a binary semantic image classification problem where only very small parts of the images are positive, most of it is negative. In the training data I have a positive rate of around 0.023, which is a large imbalance (factor 43). Now when I…
Martin Ueding
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2
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1 answer

How do you train a semantic segmentation model to optimize for IoU rather than accuracy?

I am currently building a U-NET semantic segmentation model on Tensorflow Keras to classify pixels as belonging to or not belonging to a class. For this problem, I've isolated the masks for only one class (even if multiple mask classes exist)…
stevemeisterr
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1 answer

Why is my training loss not changing?

I'm trying to train a semantic segmentation model based on this architecture, using this one as a base. The base model uses about 10 ReLU activations, and when implemented according to the first paper, the number jumps up to 14. The input images are…
Ad Ve
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1
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2 answers

High image segmentation metrics after training but poor results in prediction

I'm trying to build a model with Keras that predicts four classes of features from microscopy noisy images which cover about 10 - 30 % of the image. I'm using U-net because my dataset is small (150 images for training and 30 images for validation).…
Capdi
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1 answer

Pixel labelled image is must for semantic segmentation using deep learning in matlab?

I have large set of CT images containing lung regions. But I don't have corrosponding pixel labelled images. So how I could do semantic segmentation using DL in matlab. Like a test program I created 6 pixel labelled images using image Labeler. But…
Silpa
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1 answer

Correct way of computing dice score for image segmentation?

In binary image segmentation, for given a set of images, it's true mask and predicted mask. How do you compute dice score? Should I compute the dice score for each image separately and then find mean across all images? Or compute the dice score for…
spb
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Semantic segmentation to instance segmentation

Having a mask from semantic segmentation I want to split it to list of non-overlapping instances masks(like an output from instance segmentation). Do you know some fast algorithm, approach, tool or library to do this? I have found one python…
Brans Ds
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How to approach coarse-grained semantic segmentation?

I’m looking at doing something like semantic segmentation of images but where I only have pretty coarse-grained labels - roughly, for each 32x32 patch, I know if the answer should be “yes”, “no” or “unknown”. I’d like to start with a pretrained net…
Alex I
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1 answer

Does Field of View in Camera affects the performance of Keypoint detection and semantic segmentation model?

I have two cameras to capture images for training keypoint detection and semantic segmentation model. One camera has smaller field of view and the other has larger field of view. Let's say, I capture two sets of data using both the cameras and train…
Raghuvaran P
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1 answer

The channel dimension of the inputs should be defined. Found `None`

Hello I'm trying to use SegNet in my project with tensorflow, for educational purpose. And I'm surely following someone else's code on GitHub: conv_14 = Conv2D(512, (kernel, kernel), padding="same")(unpool_1) But it is giving me something like: The…
Danial
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Pre-trained models for semantic segmentation of satellite images

I'd like to use semantic segmentation of satellite images but I don't have the processing power to train existing models or producing one my own. Ideally, I'm looking for a U-Net CNN model that can be used together with…
lennox
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1 answer

My semantic segmentation model classifies everything as background

So, I am working on a semantic segmentation task using U-Net. The dataset is very unbalanced, with the background being by far the most common, and the last class being very scarce. First I trained it using Categorical Cross Entropy as the loss…
BMC98
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