So how to optimize a website for image search engines?
- Image name
Use describing names for your images. Name like a453kjh4.jpg won't help you get any traffic. Web crawlers are not people and they can't understand what is on the image but you can help them with precise names. Use short describing names like cat.jpg or clouds.gif.
- Alt text
Don't ever forget to add describing and precise alt text. This is the other important part for getting targeted traffic from image searches.
- Page title
Page titles are something important for any kind of search engine optimization. You must have precise, short and describing titles for your pages and images with similar content.
- Paragraph titles
Paragraph titles are very similar to page titles. One page can contain multiple topics and any topic must have its own describing title.
Optimizing for image searches is not so complex part of a SEO campaign. Done together with standard SEO optimization it can bring a lot of well targeted traffic.
Good luck!
Edit: One very useful video about image url - does Google consider the url?