How to search for image using javascript?

I wrote code that looks for specific text on a page and contains positive if it does not update. But I wanted to improve the code and make it look for lines in the source code of the page to find a specific image like this

src="https://i.dstatic.com/images/glyphish/837-palette-selected.png"

$(document).ready(function(){setTimeout(function(){varLookFor="texto "; // procurar por
        if ($('body:contains("' + LookFor + '")').length > 0) {
            alert("Achou " + LookFor);
            return;
        } else {
            location.reload();
        }
    }, 2000); // troca pra aumentar o tempo
});