OCR Word confidence in Annotations

[glenrobson]

Description

I am a harvester of IIIF content who would like to use the OCR word confidence in my index.

Variation(s)

Proposed Solutions

Some way of adding OCR word confidence from ALTO to IIIF Annotations.

Additional Background

This use case came up for Newspapers but I believe it is more widely applicable. Example Alto:

http://dams.llgc.org.uk/behaviour/llgc-id:3100022/fedora-sdef:alto/getAlto

and IIIF annotation list:

http://dams.llgc.org.uk/iiif/3100022/annotation/list/ART1.json

I believe WC is word confidence:

<String ID="PAG_1_ST1" STYLEREFS="TXT_2" HPOS="921" VPOS="2937" HEIGHT="123" WIDTH="246" WC="0.99" CONTENT="Just"/>

[jronallo]

hOCR also provides word confidence in the x_wconf value.

https://docs.google.com/document/d/1QQnIQtvdAC_8n92-LhwPcjtAUFwBlzE8EWnKAxlgVf0/preview

[cneud]

@glenrobson Yes, "WC" is used for "word confidence" in ALTO. Please note that there is an ongoing discussion with regard to how confidence values should be derived and expressed in future ALTO versions: altoxml/schema#23.