How to get labels for CTC task?

[asiasowa]

Hi,
I've been trying to do ctc_finetune but on other json files than deex.json presented in your Readme and I am wondering how you can get the labels to do this task? In deex.json, label_matrix is already a part of a file, and therefore, I cannot reproduce it to other json files, including those you have in your repository like wiki-tables-samples.json.
I would be very grateful for an advice :)