You can not directly add an image to the Hyperledger. To add an image to the Hyperledger Blockchain, you need to first convert the image into a Base64 string.
You can do the conversion using the following code:
fs.readFileSync(‘yourimageFile.jpg’).toString(‘base64’);
And then when the image is converted to the string, store it on the Blockchain like you would usually store any other string.
You can refer to the following links to know more:
https://www.thepolyglotdeveloper.com/2016/02/convert-an-uploaded-image-to-a-base64-string-in-node-js/
https://belltane.wordpress.com/2017/03/27/storing-images-in-hyperledger-fabric-blockchain/