So you don’t get a nasty letter, you need to know who created that blog post or image so you can ask permission and give credit where credit is due. When you are trying to search backwards to find the source, these searches are called “reverse searches.”

Text based reverse searches are pretty darn easy. You can use Google to search for a unique phrase from the post or turn to sites like Copyscape to quickly find out who wrote that amazing blog post (and who might have ripped them off). However, it took the brilliant minds behind the Internet a little bit longer to figure out effective tools to conduct reverse image searches.

When we talked about if it was ok (legally speaking) to use a photo on your website, one of the questions on our handy-dandy chart was: “Can you find who took it?” I mentioned that there are services available, Tineye or Google Images, which you can use to perform these kinds of reverse image searches. Today we are going to take we are going to dive in and discuss both of these tools and a couple other tricks that you can use if you are the creator and want to find where else your work is appearing online.

Google Images

When you are trying to find the source of a single image, Google Images should be your go-to resource.

Google Images lets you perform a reverse image search in one of four ways:

• Point the search to a URL
• Upload an image
• Drag and drop the image into the search box
• Use a browser plug-in to right-click from anywhere on the Internet

One of the huge benefits of Google Images (and the reason it’s my go-to resource) is the size of the database. The Google search bots are constantly crawling the Internet, meaning that it’s much more likely that the source of that image is in their database. The downside of Google Images is the fact that the algorithm is designed to give you lots of results to pick from, including visually similar results, so you might have a couple pages of results to wade through.

Tineye

I would love Tineye to be my go-to resource because their reverse search algorithm is so dang accurate. The reason it hasn’t bypassed Google Images is the size of their database. In September 2015, Tineye’s database contained just over 12.9 billion images. While this sounds like a lot, in September 2015, Instagram statistics show that its users have shared more than 40 billion images on their service. So Tineye’s database is a drop in the bucket in comparison to the number of the images available on the Internet.

Tineye can be searched using the same four methods as Google Images:

• Point the search to a URL
• Upload an image
• Drag and drop the image into the search box
• Use a browser plug-in to right-click from anywhere on the Internet

Bing Image Match

In March 2014, Bing released a reverse image search tool, Image Match. Bing only allows you to search by pointing the search to a URL or uploading an image.

I’ve only tested it three times. From this limited sample size, it appears that their database is not quite as large as Google (not surprising) and their algorithm isn’t as accurate.

Of course, just giving credit where credit is due, won’t protect you from a copyright infringement lawsuit. In order to do that, you need to get permission to use that photo.

But what if you are the creator and you are trying to find where else your work is posted?

Tricks of the Trade

All of these tools are built on algorithms that compare pixels in Image A to pixels in Image B. Once we understand this principle, we can manipulate our images to increase our chances of the algorithm finding all places your image appears. If you are having difficulty finding your image, you might want to try searching:

High-Resolution Image

Searching the high-resolution image should be a no-brainer. You want to give the algorithm a high-resolution image so it can see and compare images in the finest detail possible.

Low-Resolution Image

The reason you might want to add a low-resolution version into the mix is that it causes the algorithm to “squint.” This results in images that do not quite match on the same level of detail as the high-resolution version.

Variations

Next possibilities are any variations that you posted. For example, did you post a version on Instagram that was a 1:1 crop? Or did you upload a black & white version for your client? Sometimes the algorithm will not recognize these variations as the same image.

Rotated/Flipped

I know that this sounds a little strange, but there are two reasons for searching for a rotated/flipped version. First, it tricks the algorithm into a different way of comparing. But more importantly, this is a favorite trick of people who intentionally steal your work.

Gaussian Blur

This search has been highly successful for me. The reasoning behind this is similar to searching a low-resolution image, it forces the algorithm to “squint” at the image and see the overall shapes, rather than individual components.

Searching Services

While the above services are fantastic for trying to find out who created an image, they both require lots of elbow grease if you are the creator and trying to track where your images are appearing online. There are ways to make this less burdensome, for example, Google and Tineye will allow you to restrict results by date, so if you regularly search you can limit your results. However, there are a couple of searching services that you can use to automate the process.

Many in the photography community are fans of ImageRights. ImageRights is more than just a search tool and has a holistic approach to the issue of images being used without your permission. Their service combines search, copyright registration, and recovery. They use a proprietary search technology (ImageRights Discovery) to find and locate unlicensed uses of your images. Once they find a suspected unauthorized use, they inform you. Depending on the service level you select, they will assist you with registering your copyright with the U.S. Copyright Office. Your service level also determines the proportional split of the monetary recovery they obtain on your behalf.

Image Witness was built out of the internal needs of a stock agency to track their images. Once a month, they automatically search all images you have stored with them and ping you if you have new results. You can then log-in to your account to review them. Image Witness is built on the “freemium” model and lets you use their service free for up to five images, with service plans for higher numbers of images.

Rather than creating their own search technology, Image Raider was built to “scrape” the data from Google Images, thus making a Google Images search automatic. Image Raider is a credit system with each search costing a single credit. However, you control how many images are searched and how often. If they find any results after your scheduled search, you’ll be notified.