Module: DL_OCR

Loads a deep learning model and prepares its execution on a specific target device.

Name Type Range Description
Input value inModelDirectory ReadCharactersModelDirectory* A Read Characters model stored in a specific disk directory. If not set, model is chosen on the basis of inPretrainedModelType.
Input value inPretrainedModelType OcrPretrainedModel Type of a pretrained model (distributed with Deep Learning add-on) to deploy. Ignored if inModelDirectory is set.
Input value inDeviceType DeviceKind* A type of a device selected for deploying and executing the model. If not set, device depending on version (CPU/GPU) of installed Deep Learning add-on is selected. If not set, device depending on version (CPU/GPU) of installed Deep Learning add-on is selected.
Input value inDeviceIndex Integer 0 - An index of a device selected for deploying and executing the model.
Input value inExecutionHint OcrDeployHint* Prepares the model for an execution with provided settings in advance
Output value outModelId ReadCharactersModelId Identifier of the deployed model


The pretrained models are described here.


  • In most cases, this filter should be placed in the INITIALIZE section.
  • Executing this filter may take several seconds.
  • This filter should be connected to DL_ReadCharacters through the ModelId ports.
  • By default, the model distributed with Deep Learning add-on will be deployed. If you have a model trained for a specific case, you can set inModelDirectory to it. Please note, that inModelDirectory have to point to existing directory, containing subdirectory named "models", which, in turn, contains file named "model" .
  • If inExecutionHint is set to NIL, first execution of DL_ReadCharacters will likely take much more time than following ones. To avoid this, fill inExecutionHint with expected parameters of following calls to DL_ReadCharacters. A size of an analysed area may be obtained from the diagnostic output of DL_ReadCharacters. If you still experience huge performance hit on some calls to DL_ReadCharacters, add another DL_ReadCharacters_Deploy with inExecutionHint filled with parameters from a problematic call to DL_ReadCharacters.


  • Passing NIL as inTargetDevice (which is default), is identical to passing DeviceKind::CUDA on GPU version of Deep Learning add-on and DeviceKind::CPU on CPU version on Deep Learning add-on.
  • GPU version of Deep Learning add-on supports DeviceKind::CUDA and DeviceKind::CPU as inTargetDevice value.
  • CPU version of Deep Learning add-on supports only DeviceKind::CPU as inTargetDevice value.

Complexity Level

This filter is available on Basic Complexity Level.

Disabled in Lite Edition

This filter is disabled in Lite Edition. It is available only in full, FabImage Studio Professional version.

Filter Group

This filter is member of DL_Deploy filter group.

See Also

  • DL_ReadCharacters – Performs optical character recognition using a pretrained deep learning model.