In order to build a custom data generator for large datasets in TensorFlow, you can create a Python generator function and wrap it with tf.data.Dataset.from_generator. This is especially useful for handling large datasets that cannot fit into memory. Here is the code snippet you can refer to:
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In the above code, we are using the following:
- Define a Generator Function: Use yield to stream data one sample at a time.
- Wrap with tf.data.Dataset.from_generator: Specify output types and shapes using output_signature.
- Apply Optimizations: Shuffle, batch, and prefetch data to improve performance.
Hence, this approach allows efficient data loading for large datasets, ensuring scalability and flexibility.