Hi,
I think that your problem is this:
stackoverflow.com/questions/5773032/how-...upon-resizing-images
Your image is saved with a color profile different than sRGB.
And GD2, which is the PHP library to handle images transformations only supports sRGB.
It is recommended to only use sRGB images if you want to use them on the Internet.
So please check that and make sure that you use images with sRGB.
As written on the link above, the only solution to supporting images with other color profiles would be to use ImageMagick instead of GD2 to process the images, but only GD2 is installed by default with PHP so if we were to support ImageMagick library, it would work only for a handful of users of HikaShop. And even then, you would have issues with customers of yours using old browsers not supporting the color profiles you're using in your images. So it's best to stick with images in sRGB.