Hi, Is it possible to create an OCR application inside netsuite as suite app?

It would be possible, but you'd have to send uploaded documents out to an external platform that can handle the OCR functions. Moving customer documents out of their NS account could be problematic from a privacy standpoint. We've built something for our company that does OCR for uploaded documents. We use AWS Textract for the OCR function.

is it not possible to extract the info without sending it to an outside platform?

Someone else might have some ideas, but we couldn't come up with anything. You're pretty limited on the server side with what external libraries. you can use.

Since there are optimized, purpose-built services for OCR I would not recommend to build it purely inside NS. That said, in theory any external JS library can be used in NetSuite so long as SuiteScript (2.1) has sufficient language support or such support can be polyfilled. Sometimes it takes some effort to get a library working.

The ammount of effort for this would far exceed just hitting an OCR api