How to send image in postman

I am using laravel lumen to make API. I have to convert and save blade file in image and have to send image path in api.

How to do that? I am not getting idea. I tried by below code-

https://laracasts.com/discuss/channels/lumen/how-to-convert-view-file-in-image-and-return-in-api-in-laravel

But not working. What I am doing wrong? Or any other solution?