Turning on OCR for a document can be done in the "Document properties" pane. To access this, right click your document and select "Properties".
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With the document properties panel open you will find the OCR toggle.
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The time it takes to turn on OCR will vary, depending on the document size. You will see this progress indicator while OCR is being applied.
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A small magnifying glass icon will appear next to the document icon when OCR is applied.
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