This is just a review of the CTC (Connectionist Temporal Classifier) loss function developed by Alex Graves
In this notebook im trying to calculate the alpha values (CTC forward variables) in order to compute the CTC loss

For more in deep understanding of how CTC works, you can read this articles:

• Speech recognition system using CTC
• OCR model arquitecture using CTC
• OCR model implemented on Keras using CTC

You can read also the Alex Graves paper:
Connectionist Temporal Classification: Labelling Unsegmented Sequence Data with Recurrent Neural Networks