Here you can donwload Scale2x containing an example program about to apply the effect on .png image and a very fast MMX implementation.

File	Description
scale2x-3.0.tar.gz	The sources for GNU/Linux, Windows and any other operating system.
scale2x-3.0-windows-x86.zip	Windows binary.

Other implementations can be found in the contrib/ directory.

License

You are allowed to use the Scale2x implementations in your program if it's released with the GPL license, or alternatively under all the following conditions:

• the program is not used in commercial activities.
• the whole source code of the program is released with the binary.
• derivative works of the program are allowed.

Instead, you are free to use the algorithm, but please call the effect "Scale2x".

scale4x

scale2x

original