Unet model result

I saw one person converted binary mask's vector to matrix (128,128,2) using tensorflow.keras.utils.to\_categorical(mask,num\_classes =2 ). and used sofmax function in models output in Binary Semantic Segmentation problem and got about 98% accuracy with only 5 epochs. With the same data I have used masks itself as a 128x128x1 size and used sigmoid. When I train Unet model I get good results in 50 epochs. How can I improve my model to get best result like this person with 5 epochs. …

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