How does the free reverse image search work

The complete guide to performing a reverse image search

There are times when a picture is worth a thousand words. But you just can't find the key word to describe it. Here, Reverse image search comes to the rescue: it is a special type of search that uses an image instead of a keyword and retrieves similar images.




The umbrella term that covers the definition of reverse image search is content-based image retrieval (CBIR). The fun is playing around with it. Reverse image search comes in handy when trying to spot faces or identify objects. Imagine looking for a similar type of furniture to what you have a photo of. It is practically impossible to describe it with keywords. Expand it and you can search for art, architecture, locations, etc. Another important use could be looking for your copyrighted images that are being used by someone else.


The success of a search depends of course on the index of the search engine. These are still the early days, but reverse image search engines are developing rapidly.

Here are two to try:





Google - search for picture

Google is the keyword in search. Search by image gives you the edge of image search. Simply drag an image with the mouse into the search box. This is a new addition to Google Image Search and is still being rolled out.

You can also upload an image from your desktop or paste the url of the image into the search box.

The results show related or similar images with different representations, sizes and resolutions. The accuracy of the results increases if the image used is known.

This is what Google says:

Google uses computer vision techniques to match your picture with other pictures in the Google Picture Index and other picture collections. From these matches, we try to create an accurate text description for your image and find other images that have the same content as your search image. Your search results page may show results for this text description as well as related images.

Chrome and Fire Fox browser extensions are also available to speed up your search.





TinEye

Google likely took its cue from this early starter and reversed the image search. TinEye is a reverse image search engine that has managed to hold its own against the competition. Its 2 billion strong index (and growing) could be one of the reasons. Again, you can browse the image url by uploading it or copying and pasting it.

The search is pretty quick; You get the source of the picture, can compare changed pictures and check if larger versions are available. With the free version of TinEye, you can perform 50 searches per day and up to 150 searches per week.

TinEye also offers browser extensions for Chrome, Fire Fox, Internet Explorer, and Safari. With the plug-ins you can right click on an image on a webpage and do a reverse image search. If your browser doesn't support browser extensions, TinEye will bookmark it which will send the image url to the reverse search engine.

The best news about reverse image search is that you no longer have to worry about spelling or typing. Do your own reverse image search and let us know the results.