Image compression

[Chaste Degenerate]

Not sure if this is the right spot, bit this is a resource I think would be of importance:

https://compressor.io/

Upload images and it reduces the file size with little noticeable effect to the image. At least that's the way it's supposed to work, haven't tried it yet.

[DarkChibiShadow]

I've been using this program: http://optipng.sourceforge.net/ for the past few weeks and not only is it really simple to use (just drag and drop items over the .exe) it's also free and you can compress multiple images at once without much hassle at all. Best used for .pngs, especially those with transparent backgrounds.

[Chaste Degenerate]

I finally downloaded this to try it, and to compare it to the website. Apparently you are only supposed to download the Win 32 version. The other versions don't have the EXE file.

The program took a 2,756 KB file and reduced it to 2,419. A 12.2% reduction. I cannot tell the difference between the two images.

The website took the same 2756 KB file and compressed it to 2413. A whole 6 KB more. Again can't tell a difference.

I also decided to compare the lossy compression to the lossless, and was able to cut it down to 872 KB. A 68.36% reduction. This time I could tell a little bit of a difference if I was looking. I can see minor changes, but I think that if I didn't know about it, or didn't see the original image I probably wouldn't even know. Probably the biggest issue would being losing a little highlight off of her shoulder

So to be fun I decided to use Photoshop to convert the image from png to jpg. I cannot tell the difference, but the file dropped to 1,070 KB. A drop of 61.12% Then I exported it and reduced the quality to 90%. It is now 674 KB, and I still cannot tell the difference. That is 75.54% smaller.

This convinces me to use jpg for backgrounds and fully rendered images, but obviously will still need png if I need a transparent background, so the program would work fine or the website if I don't have a problem with the results of the lossy image.

This is all based on one image. But the fact that I cannot tell the difference between a 2,756 KB png and a 674 KB jpg is very influential in how I will develop my games.