How to integrate AWS S3 and Azure Cognitive Services (OCR)?

Hi.

I understand that you want to use private Amazon S3 directly as input to Azure Cognitive Services.

You cannot specify a private Amazon S3 URL directly to the Vision API.
It must be a public URL that the Vision runtime in Azure can access.

Instead you can use the same approach for sending local images.

https://learn.microsoft.com/en-us/azure/cognitive-services/computer-vision/how-to/call-read-api#submit-data-to-the-service

In the above, image data is specified in binary in the request body when sending local data.

Your application should use IAM to retrieve data from a private S3 bucket and send the data as binary before calling the Vision API.