Search a coin by image [solved]

Hello,

I create this topic to track the idea to be able to search in the catalogue by image in addition to the easy search and the advanced search.

This would help for coin identification. The user would upload an image and the search engine would return the most visually similar coins.

A bonus would be to have a smartphone application to ease the process: use the phone camera to scan the coin and see the catalogue entry immediately.

Hmm... would be nice, but I've tried using Google image search before to find coins and the results it produced were less than useful, so I'm kinda skeptical about whether it's actually going to work.

This would be tough to achieve when photos of one coin can drastically different from each other.
You could have a traced image with edge detection but that would still be limited.

Like this for example using Xavier's avatar image.

You look for this coin with a similar image to this


The traced image that the search engine would compare it to would look like this.



But again, there can be drastic differences in images of the same coin like the image below for example. the image is skewed and may not be recognised due to its dimensions.

Awesome pic

OpenCV ;)

Quote: "druzhynets"​OpenCV ;)

​Haar cascade classifiers.

That may be just awesome feature, however like Houseofham, I'm very skeptical if Xavier will succeed to implement that feature well enough to be able provide results better then Google images search. We all know that Xavier is a good web-master, however image processing is completely different study field.

Previously I worked on similar coin recognition application and received quite poor results.

First, you need to ask user to make quality photo of the coin on white background, otherwise simple edge detection algorithm may return you something that you can hardly continue to work with. Few examples:



Second, you need to have in your database set of good quality pictures of same coin (in different quality, illumination etc.) in order to have as much markers as possible. You never know what kind of photo user will provide you, even if you able to stabilize illumination, angle of the photo and other parameters, the coin may be shabby, oxidized, damaged. Small example of same coin:


And there are a lot of other problems... for example can the application find difference between these two coins?
https://en.numista.com/catalogue/pieces1231.html
https://en.numista.com/catalogue/pieces20723.html
The difference is minimal, but that's what differ between moderate and good coin recognition app.
By the way, take a look on images of these coins, the one is very small and the second one is blurred. As I previously told, coin detector should have good quality pictures of the coins in order to build database of coin's markers.

Can Xavier solve all these problems? I'm very skeptical, but hope he can. Let's wait and see.

Quote: "Ahmad Xiad"​can anyone tell me about this coin

Hello. Welcome to Numista.
​Not sure why you posted this in this thread or this forum but please read this and post again here.