My bank offered me (and anyone else they serve) an opportunity to customize my credit card. The few restrictions they had were along the lines of refraining from images that are offensive, look like money, or violate copyrights.

I'm a little bit of a fan of deep space, and have tried a few times to submit images, or parts of images that I've found on sites like APOD or Wikipedia, carefully checking to see that there are no use constraints.

I didn't just grab random images from random websites based on search results. I tried to be respectful and honor the copyrights and permissions of the photographers and sites I searched.

I finally settled on this image of baseballs, because I'm als a little bit of a baseball fan. It's a bunch of no-brand (visible) baseballs. Surely I could have taken the picture, if I had a stack of baseballs and any kind of photographic aptitude. The final design will be a bit of this image, cropped using their on-line tool, wrapped with their logos, and stamped with my card information. I should have it in a week or so.

Each of the other requests was denied, probably because they doubted my ability to use the image, from a permission stand-point. Well, they didn't decline with that much clarity; each message contained the whole list of criteria, and didn't specifically mention permission. Certainly images of planets or nebulae aren't offensive, political, or mistaken for money or other endorsements, which left me to conclude copyright or permission was the reason.

This made me wonder in part how they found the images to test for copyright. This made me wonder how to search with images at all.

I certainly didn't look beyond the site from which I snagged the image, unless an origin was cited, and then I'd look there. For example, Wikipedia makes every effort to display only redistributable and reusable art, and clicking on any image on the site will take you to a page that lists origins, copyrights, and  rights of re-use, where known; and it will tell you if it doesn't know. I didn't try to use any of those that didn't say they were available for reuse.

This led me on a quick little search to find how to search by an image, instead of for one. If you use Google, for example, there's an "images" link on the side of any search results page that will display images matching your criteria; if you searched for "baseball" or "space" the images would show images with names that seem to match, but also other images on pages that had that topic.

Helpful in finding images by a particular subject, but not so useful for finding anything based on an image. I wondered if there were search engines that could take an image and

The top of Google's search results (for a number of different criteria--they must pay to be there, right?) is TinEye, a search engine that tries to find the same image by different names and sizes. On their search form, you upload an image you may have on your computer, or provide a URL for one somewhere else on the Internet, and they provide results of other matching images.

It's surely not a exhaustive search engine, yet--they are growing their baseline. A lot of images I tested with, which I grabbed from random searches for this purposes, weren't found. Some were, though. I also played with their plug-in for Chrome, which sped up my tests by allowing me to search without clipping source URLs or saving images to upload.

It's currently incapable (as far as I can tell) of finding images based on parts of an image. I tested this by finding an image for which they did have results, then I saved it, cropped part of it out, and searching again with just the cropped portion. It didn't find the original image. It also didn't find the same image when I flipped or rotated it, nor did it find it when I copied the image from the web page using the Firefox Abduction plug-in.

It did, however, find the same image when I saved it as a different format, such as PNG or GIF instead of JPEG. It also showed the JPEG and GIF images in the search results.

This made me wonder if the top item on the list maybe wasn't the best ('though it's still a good find). I didn't do an exhaustive search for "best" myself, but did find some others.

Another quick search result was GazoPa, which did find similar images using cropped and reversed examples. While it didn't always find the same image I was testing, it had a lot of similar images. The baseball image, for example, didnt' find the same image (neither did TinEye), but yielded similar pictures, but with different elements, such as a onions and donuts. Curiously, it also found a couple of baseball players, and flowers.

GazoPa also allows you to search by URL or keyword. They also allow you to sketch an image to search, using the shapes and colors provided (it says). I scribbled a crude airplane, and it returned a number of aircraft, in different perspectives, both fixed-wing and helicopters.