Hi,

Have you encountered this problem, you know, when you have no choice but to use an img tag instead of a block type tag with a css background-image in an html page, and these images which not serve style are found indexed?

I found many times in this situation during creating and integrating branding site, and I have to include resizing percentage.

These are the images that construct the page graphically universe but in no way serve the SEO content have no particular meaning with it. However, the image search pages on the search engines find themselves “polluted” by them, rather than proposing relevant content.

Img tag possess two characteristics that the background-image has not :

• Automatic detection of dimensions by the browser
• Scalability of the image by percentages

I am aware that the first characteristics could be remedied using CSS3 and background-size (cover/contain values) property in particular (but not the second one). However, in a commercial context, the importance is to reach a maximum of Internet users, we limit the application of new and favors standarts and cross-browser compatibility.

The background-image have another quality

•  They are not indexed by robots

Although it is possible to add a rule entries in the robots.txt file with such a pattern on image names, I do not find it very suitable.
Example of an image is calling “character-noindex.jpg” in “images” folder:

User-agent: *
Disallow: /images/*-noindex.jpg

I would find it more appropriate to add to img tags, an attribute  noindex = “noindex” like robots meta tag. This would check the flow of indexed images.

< img src = “./ images / character.jpg” noindex = “noindex” alt = “A character used for the style but uninteresting from an SEO point of view” />

What do you think about ?

Aurélien