Image Comparer algorithm in a DLL

This page is for software developers who want to use our image comparison algorithm in their own projects.

Image Comparison Algorithm for Windows

Bolide Software can sell you our own unique algorithm as a small dll file (about 120KB) from only US$199. We reserve the right to change prices with time. We do not provide our algorithm sources and will not explain how it works. The product contains a dll file, with only one exported function with two bitmap pointers in and similarity percentage out.

Here is an exported function definition using, Delphi rules:

function CompareHBitmaps(bmp1,bmp2:BitmapType):NumericType;stdcall;
All you need is to import this function into your project and pass two bitmap pointers and you get the similarity percentage! We also have a modified version of the DLL with image "hashes" support. It is able to make some precalculations and return a 768 byte image hash. You can use these hashes for comparison then. The price for the modified DLL is $50 higher than for the standard one.

You can evaluate our algorithm quality and processing speed using our Image Comparer software.

Download Image Comparer

Image Comparison Algorithm for Linux

We have a Linux version of or algorithm as well. It is distributed as Linux Shared Object (.so) file. PHP version is also available by request.

How to purchase

We do not publish the order link here for a reason. First, you should ensure that you are able to use our DLL with your project. Contact us and describe your needs and your project environment. We will send you a "crippled" version of our DLL with the source examples, to check for compatibility with your project. It works exactly as the real one, but returns random values instead of actual similarity percentages.

There are three types of license for image comparison DLL (Prices valid for the standard DLL).

Developer License, US$ 199

You are hereby granted a limited, royalty-free, right to use the SOFTWARE to design, develop, and test Developed Software. You are also allowed to distribute the software inside your organization for up to 100 copies.

Limited License, US$ 399

You are hereby granted a limited, royalty-free, right to use the SOFTWARE to design, develop, and test Developed Software. You are also allowed to distribute the software inside or outside your organization for up to 10,000 copies.


Unlimited license, US$ 1999

You are hereby granted a limited, royalty-free, right to use the SOFTWARE to design, develop, and test Developed Software. You are also allowed to distribute the software inside or outside your organization for an unlimited number of copies.

Our customer say

Image Comparer - Fantastic!

"Just want to thank you for the great program!!! It knows beans really! It's really awe-inspiring! Really cool! You know I am really keen on taking photos and have thousands of them on my PC. I was even afraid to try to organize them manually... Yecch!! But Image Comparer did it nicely and very quickly indeed - it managed to find all even slightly similar photos! Fantastic! I would never do myself! Not on my life! So, thank you and keep it up!"
- Rating: 4.8 -