Convert TensorFlow Attention OCR Model

This tutorial explains how to convert the Attention OCR (AOCR) model from the TensorFlow* Attention OCR repository to the Intermediate Representation (IR).

Extract Model from Library

The easiest way to get an AOCR model is to download aocr Python* library:

pip install git+

This library contains a pretrained model and allows to train and run AOCR using the command line. After installing aocr, you can extract the model:

aocr export --format=frozengraph model/path/

After this step you can find the model in model/path/ folder.

Convert the TensorFlow* AOCR Model to IR

The original AOCR model contains data preprocessing which consists of the following steps:

  • Decoding input data to binary format where input data is an image represented as a string.

  • Resizing binary image to working resolution.

After that, the resized image is sent to the convolution neural network (CNN). The Model Optimizer does not support image decoding so you should cut of preprocessing part of the model using ‘ input’ command line parameter.

mo \
--input_model=model/path/frozen_graph.pb \
--input="map/TensorArrayStack/TensorArrayGatherV3:0[1 32 86 1]" \
--output "transpose_1,transpose_2" \
--output_dir path/to/ir/


  • map/TensorArrayStack/TensorArrayGatherV3:0[1 32 86 1] - name of node producing tensor after preprocessing.

  • transpose_1 - name of the node producing tensor with predicted characters.

  • transpose_2 - name of the node producing tensor with predicted characters probabilties