Error using tesstrain with START_MODEL - failed to continue

[Keith Smith]

Hi,

Could someone help me understand why I am getting the following error when using tesstrain with the START_MODEL option? 

      Failed to continue from: data/micr_ref/micr.lstm

From my local tesstrain repo (cloned from https://github.com/tesseract-ocr/tesstrain), I have the following in my data directory:

data

├── micr-ground-truth

│   ├── micr-1.gt.txt

│   ├── micr-1.tif

│   ├── micr-2.gt.txt

│   └── micr-2.tif

└── micr_proto-ground-truth

    ├── micr.gt.txt

    └── micr.tif

I am using what is in 'micr_proto-ground-truth' to build my proto model, which I then use as a START_MODEL for training the micr model from 'micr-ground-truth'.

More specifically, I issued the following commands from my tesstrain repo:

      gmake tesseract-langdata

      gmake proto-model MODEL_NAME=micr_proto

      mkdir -p usr/share/tessdata

      cp data/micr_proto/micr_proto.traineddata usr/share/tessdata

      gmake training MODEL_NAME=micr START_MODEL=micr_proto

The final command fails with the following error:

      Failed to continue from: data/micr_proto/micr.lstm

      gmake: *** [Makefile:327: data/micr/checkpoints/micr_checkpoint] Error 1

Can anyone tell me what I am doing wrong?

Background Info

My ultimate goal is to train tesseract to OCR the MICR line from the bottom of check images with 99+% accuracy.

For my test/training set, I have more than 20K tif check images which I have cropped and cleaned using opencv to include only the bottom portion which contains the MICR line.  I also have the gt.txt file for each cropped image.

I tried the mcr.traineddata (from https://github.com/BigPino67/Tesseract-MICR-OCR/blob/master/Tessdata/mcr.traineddata) with multiple PSM values, but the accuracy was very low.

I also tried using tesstrain directly as follows with my entire training set in the data directory:

    qmake training MODEL_NAME=micr

but the resulting micr.traineddata yielded even worse results.

So now I am trying to build my proto model as described above using a single reference image, and then to use that as the START_MODEL for my training, but I am hitting the error I mentioned above.

Is my approach incorrect?  If yes, can you please direct me?  I am not finding the documentation extremely clear, so I obviously may be doing something stupid.

Thanks much for the help,

Keith

BTW, I am attaching the data.zip (contents of my data directory) in case someone wants to reproduce this.