Recently I was faced with an unusual task of finding the source of an image on my hard drive. Firing up google I found that there are many ways of doing this.
The best site I came across was tineye.com. What you do is upload a image from you hard drive (or you can search for one), and then it analyzes the image and searches for similar images across the internet. In the above picture it searched and compared over 1 billion images in just over 1 second which is amazing to say the least. This image recognition technology has really developed fast. I remember a couple of years ago there was a similar service which took ages to search and the results were buggy. It also gives you the metadata of the images and the level of similarity.
Using Google Images:
If however you came across a image using a search engine, say google images, you can search for similar images using Google lab’s ‘similar images’ feature. Just go here , search for image and having found it click on ‘Similar Images’. This is a new beta feature in google images, which has the drawback that you can’t use an image you already have. Live image search also has a similar feature.
Now after clicking on Similar images for the second image google gives us:


