Hi , is there any appian utility which can scan a bar on the image ? ...

Check out the "Barcode and QR Code Utilities" component

@tim : Can you tell me how will be able to use that utility? Is there any example application for the same ?

forum.appian.com/.../6475

If you look at the old discussion topic there is a demo application attached to it which should help demonstrate it's use. Good luck!

@tim : Is the Barcode and QR Code Utilities component appian approved ?

It's approved for use in Cloud deployments but like all shared components it is not officially supported. For example there are no guarantees that it will work for each new release of Appian.