Transfer OCR result to metadata field

This Goobi workflow step plugin allows to read the OCR fulltext of all images of a process to be written as plaintext into a given metadata field.

Introduction

This step plug-in for Goobi Workflow automatically reads the OCR results of all associated files, combines them and then saves them in a configurable metadata field within the METS file.

Details
Identifier	intranda_step_ocr_to_metadata
Source code	https://github.com/intranda/goobi-plugin-step-ocr-to-metadata
Licence	GPL 2.0 or newer
Documentation date	30.05.2023

How the plugin works

The plugin first checks whether the directory with OCR results in TXT or ALTO format already exists. If these exist, the content of the files available there is read in and combined into a complete full text. Finally, this combined full text is saved in the metadata field of the METS file that was defined in the configuration file. Any existing content of the metadata field is overwritten with the full text.

Installation

The plugin consists of the following files:

plugin_intranda_step_ocr_to_metadata.jar
plugin_intranda_step_ocr_to_metadata.xml

The file goobi_plugin_step_ocr_to_metadata.jar must be installed in the correct directory so that it is available at the following path after installation:

/opt/digiverso/goobi/plugins/step/plugin_intranda_step_ocr_to_metadata.jar

In addition, there is a configuration file that must be located in the following place:

/opt/digiverso/goobi/config/plugin_intranda_step_ocr_to_metadata.xml

Configuration

The configuration of the plugin is done via the configuration file plugin_intranda_step_ocr_to_metadata.xml and can be adjusted during operation. The following is an example configuration file:

<?xml version="1.0" encoding="UTF-8"?>
<config_plugin>
    <!--
        order of configuration is:
          1.) project name and step name matches
          2.) step name matches and project is *
          3.) project name matches and step name is *
          4.) project name and step name are *
    -->
    
    <config>
        <!-- which projects to use for (can be more then one, otherwise use *) -->
        <project>*</project>
        <step>*</step>
        
        <!-- Name of the field where to store the OCR result -->
        <metadataField>AdditionalInformation</metadataField>
    </config>

</config_plugin>

Parameter	Explanation
project	This parameter determines the project for which the current block <config> is to apply. The name of the project is used here. This parameter can occur several times per <config> block.
step	This parameter controls for which workflow steps the block <config> is to apply. The name of the step is used here. This parameter can occur several times per <config> block.
metadataField	This parameter defines the typecof the metadata field that should be used to store the OCR result.

Integration of the plugin into the workflow

This plugin is integrated into the workflow in such a way that it is executed automatically. Manual interaction with the plugin is not necessary. For use within a workflow step, it should be configured into the workflow as shown in the screenshot below.

Integration of the plugin into the workflow