First off: You need to find a way to make an animation. For a halftone animation Easytoon is your best go. There's no aliasing to worry about and it's easy to use.
You're going to make two animations.
They have to be the same length in frames. Save the individual animations as separate GIFs somewhere.
Now, open both GIF files in an image editing program (like photoshop). It should open them as one file with each slide being individual layers.
You need to decide which animation is going to show on a white background, and which animation is going to show on the blue background.
- White: For each layer you need to delete the white parts. Take a magic wand tool (or something similar) and delete the white. Then, select all the black and recolor it to match the blue background. Then, copy the layer onto a new file, and then resize it to 75x75 (the avatar size). Halftone the image. When you work with the Blue image you need to make sure that when you halftone it, it fills the empty spaces of the White image.
Do the same for the Blue animation and place the white and blue halftone layers on the same file and merge them.
Do this for each frame until you have both animations in one file. Then you export it into an animated GIF (for photoshop elements it was called "Save for Web"). (For photoshop elements you need to select the "animate" option, and make the "matte" option set to NONE)
- Blue: For blue it's the exact same thing, except you delete the black part, and when you halftone it, make sure it's inversed.
It's very complicated to explain for me, so this might be confusing. But, I'm not sure if I can explain it any better :/
