On his blog, Laurent wanted to know who is this guy. I though it was an interesting starting point to see how good is Retrievr, “an experimental service which lets you search and explore in a selection of Flickr images by drawing a rough sketch”.
Although my drawing skills really needs to be improved (and their drawing tools more refined – always blame the others for your weaknesses 😉 ), a first sketch gives some interesting results (see screenshot below): 7 retrieved photos (44%) show a b/w human face in “frontal view” (if you count the dog, it’s even 8 correct images).
If I just give the photo URL, results are not so good (see screenshot below). I am nearly 100% sure that it’s because it’s a greyscale photo scanned as a color image.
When I upload the image on my harddisk, convert it to a greyscale image and upload it on Retrievr, now it gives more expected results: 10 images show a person with his/her hair (63%), either from the front or from the back.
So this photo is not among the “most interesting” ones on Flickr (it is even probably not on Flickr). I suppose that if one applies Retrievr on a larger subset of photos, we’ll have a higher probability to find it (but it will also increase noise, i.e. the number similar photos). If you like playing with Flickr, other intersting Flickr mashups can be found here.
Jean-Etienne's blog 