To implement semantic segmentation using Keras, use an encoder-decoder architecture like U-Net, DeepLabV3+, or SegNet, train on pixel-wise labeled data, and apply techniques like data augmentation and dice loss for better accuracy.
Here is the code snippet given below:

In the above code we are using the following techniques:
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Uses U-Net Architecture:
- Encoder (downsampling) extracts features, and decoder (upsampling) reconstructs the segmentation mask.
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Skip Connections for Fine-Grained Details:
- Prevents loss of spatial information by concatenating encoder and decoder features.
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Pixel-Wise Classification with Sigmoid Activation:
- Each pixel is assigned a segmentation class label.
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Custom Loss Functions (Dice Loss or Cross-Entropy):
- Can be optimized using binary/categorical cross-entropy or Dice coefficient loss for better segmentation accuracy.
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Supports Multi-Class Segmentation (num_classes > 1):
- Modify the output activation to "softmax" for multi-class segmentation.
Hence, semantic segmentation using U-Net in Keras enables pixel-wise classification, leveraging skip connections and loss functions like Dice loss for precise object segmentation.