Use Case and High-Level Description

This is a network for text recognition scenario. It consists of ResNext101-like backbone (stage-1-2) and bidirectional LSTM encoder-decoder. The network is able to recognize case-insensitive alphanumeric text (36 unique symbols).


-> openvino


Metric Value
Accuracy on the alphanumeric subset of ICDAR13 0.8887
Accuracy on the alphanumeric subset of ICDAR03 0.9077
Accuracy on the alphanumeric subset of ICDAR15 0.6908
Accuracy on the alphanumeric subset of SVT 0.83
Accuracy on the alphanumeric subset of IIIT5K 0.8157
Text location requirements Tight aligned crop
GFlops 0.2726
MParams 1.4187
Source framework PyTorch*


Image, name: imgs, shape: 1, 1, 32, 128 in the format B, C, H, W, where:

  • B - batch size
  • C - number of channels
  • H - image height
  • W - image width

Note that the source image should be tight aligned crop with detected text converted to grayscale.


The net output is a blob with name logits and the shape 16, 1, 37 in the format W, B, L, where:

  • W - output sequence length
  • B - batch size
  • L - confidence distribution across alphanumeric symbols: #0123456789abcdefghijklmnopqrstuvwxyz, where # - special blank character for CTC decoding algorithm.

The network output can be decoded by CTC Greedy Decoder or CTC Beam Search decoder.

Use text-detection demo

Model is supported by text-detection c++ demo. In order to use this model in the demo, user should pass the following options:

-tr_o_blb_nm "logits"

For more information, please, see documentation of the demo.

Legal Information

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