Is setting image dimensions via div img class the same as img class

Question

Trying to speed up my site and i run into the specify image dimensions to avoid reflow and repaints.

If i have images in divs with <div class="class"> .class img {height: xxxpx; width: xxxpx;}

Wouldn't that be the same as setting dimensions within <img class="class"> .class {height: xxxpx; width: xxxpx;}?

Just wondering if it works the same way as im getting the specify image dimensions warning in gtmetrix.

Answer 1

Yes, it is the same. And, you can ignore the warning from gtmetrix.

http://gtmetrix.com/specify-image-dimensions.html

Page Speed currently only detects image dimensions that are specified via the image attributes. If you are specifying the dimensions via CSS, then you can safely ignore this recommendation.