From URL images to animated GIF

I wanted to create an animated GIF using images I found on the internet, the reported cases of Lyme disease in the United States from 2001 to 2014. The images are located on the CDC website for Lyme disease, named map5 through map18.

My original intention was to explore the capabilities of R to do this. However, the solutions I found seemed to rely on another software package, ImageMagick, which I didn't want to install. So, I punted on using R.

Next I tried GIMP (which I already had installed), but I didn't quickly find a way to open/import several images from URLs as layers. So, I punted on using GIMP as well.

Finally, I decided to try GIPHY. GIPHY had an option to create a slideshow where I could pretty quickly (but still, one at a time) copy and paste each of the image URLs to create an animated GIF. I copied each of the images once, except for the last year (2014), which I copied a few times, so that when the GIF goes through its continuous loop, it pauses for the last year of mapped data.

I'm pleased with the results, but not with the process.  I was looking for a solution with code, and came up short.

 
CDC data via GIPHY

I shared the GIF on Twitter ...

Reported cases of Lyme disease in US 2001-2014.
Data by @CDC. Animation by @giphy.https://t.co/9RFdb3ZcbO

— Jean Adams (@JeanVAdams) March 7, 2016