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 ## Introduction
 
-**ocrd_calamari** offers a [OCR-D](https://ocr-d.de) compliant workspace processor for the functionality of Calamari OCR. It uses [PAGE XML](https://github.com/PRImA-Research-Lab/PAGE-XML) documents as input and output.
+**ocrd_calamari** offers a [OCR-D](https://ocr-d.de) compliant workspace processor for the functionality of Calamari OCR. It uses OCR-D workspaces (METS) with [PAGE XML](https://github.com/PRImA-Research-Lab/PAGE-XML) documents as input and output.
 
 This processor only operates on the text line level and so needs a line segmentation (and by extension a binarized 
 image) as its input.