How to validate an endpoint returning an image, what particularly should be tested

I have the problem with validating an endpoint which is returning PNG image: GET /image/png. I am using Java + REST Assured framework. The only tests I can imagine are: to validate a status code of a response of the request and validate the JSON schema.

But I appreciate if you can advise me more tests or suggest a source of a good practice to do it.

I am novice in API testing.

Many thanks.