How to read jpeg image file from SFTP server and base64encode the image in OIC?

Hi , I have a requirement to read a JPEG file from SFTP server and pass this image in workerAPI payload to create a photo for the worker. As the workerAPI request payload requires the image to be as a string in base64 encoding, I tried to use encodeReferenceToBase64 function in OIC after downloading the file in OIC using File Adapter, however the base64 response generated , seems to be corrupted. The response generated does not match with the base64 encoded version of image generated though terminal/ the image getting posted to the worker seems to be a corrupt image and does not load.