How do I get watermarked versions of images indexed in Google search but allow users to see clean high quality images once on my site?

Question

I have a site where much of the focus are the images themselves. When people visit the website directly (with an AdSense ad shown), the image shows in normal high-quality.

When robots visit the image, they will see a watermarked version. The reason for this is because the photographer of the site dedicates his time in taking high quality pictures and it would be nice if he could profit from it.

What I tried for a month straight is to have the watermarked versions of the image indexed with Google so that when a user clicks on it, they will know more about the website since its stamped on the watermarked image. The problem is not a single watermarked image is indexed.

What I did in the past was allow everyone to see the image the same way (unmodified, no watermark, and high quality), then all the images were indexed. I learned doing that is a mistake because then people could simply download the images right off Google without seeing my website or even an ad.

In both cases, I have submitted sitemaps pointing to valid URLs and I did not use any noindex or noimageindex robot tags and I did not use robots.txt to deny access to the images.

Is there a way I can have watermarked images indexed with Google?

Answer 1

The ideal way would be handling this at nginx level.

Do something like this:

• If page requested == "/images/watermark.jpg"
• If useragent == bot
• Rewrite (internal) to something like "/images/bot/watermark.jpg"

---

Step 1

Add this in your nginx config.

map $http_user_agent $limit_bots {
     default 0;
     ~*(google|bing|yandex|msnbot) 1;
     ~*(AltaVista|Googlebot|Slurp|BlackWidow|Bot|ChinaClaw|Custo|DISCo|Download|Demon|eCatch|EirGrabber|EmailSiphon|EmailWolf|SuperHTTP|Surfbot|WebWhacker) 1;
     ~*(Express|WebPictures|ExtractorPro|EyeNetIE|FlashGet|GetRight|GetWeb!|Go!Zilla|Go-Ahead-Got-It|GrabNet|Grafula|HMView|Go!Zilla|Go-Ahead-Got-It) 1;
     ~*(rafula|HMView|HTTrack|Stripper|Sucker|Indy|InterGET|Ninja|JetCar|Spider|larbin|LeechFTP|Downloader|tool|Navroad|NearSite|NetAnts|tAkeOut|WWWOFFLE) 1;
     ~*(GrabNet|NetSpider|Vampire|NetZIP|Octopus|Offline|PageGrabber|Foto|pavuk|pcBrowser|RealDownload|ReGet|SiteSnagger|SmartDownload|SuperBot|WebSpider) 1;
     ~*(Teleport|VoidEYE|Collector|WebAuto|WebCopier|WebFetch|WebGo|WebLeacher|WebReaper|WebSauger|eXtractor|Quester|WebStripper|WebZIP|Wget|Widow|Zeus) 1;
     ~*(Twengabot|htmlparser|libwww|Python|perl|urllib|scan|Curl|email|PycURL|Pyth|PyQ|WebCollector|WebCopy|webcraw) 1;
 } 

Step 2

Check for bot in location block as: (this is generic, you can also check only for watermark.jpg)

location / {
    if ($limit_bots = 1) {
              rewrite ^/images/(.*).(png|jpg|gif) /images/bot/$1.$2 ;
            }
}

---

Answer 2

Here is an article about this where they explain how to implement it. Show full images on your own site, but only show the watermarked version in Google image search.

The basic technique is to choose which version to serve (watermarked or clean) based on HTTP Referer and User Agent.

1. If the HTTP Referer is from your own site, show the clean version.
2. If the HTTP User Agent is a bot, show the clean version.
3. All other requests get the watermarked version.

That way the Googlebot can view the clean versions (so they can rank them), but users only see the clean version once they are on your site.

Answer 3

You should not do that, for reasons already mentioned by the comments. You could filter by user-agent strings. You can find a list of about 300 common user-agents given by bots here: http://www.robotstxt.org/db.html. Run through that list and decide what to show. But doing this for every pic? You can also check your logs to find out which bots are visiting and only check on them. But again: you better mark all images and only deliver high quality after payments.

The user-agent story is an answer at: https://stackoverflow.com/questions/422969/how-to-recognize-bots-with-php