2D Animation/Shell script

This learning resource is about creating a GIF animation from the command line from several images.

Learning Task

 * Create a sequence of images with a red circle that is bouncing on the ground.
 * You can use also LibreOffice Draw file with ab image as background and a red disk is bouncing with that image background.
 * Move the red disc or circle downwards and export the altered image to img01.png, img02.png ,   img03.png ,   img04.png , ... Keep in mind, that the second bounce is not as high as the first one.
 * After you have the sequence in a folder we will create an animated GIF from image from the shell with image magick.

Generation with a Script
The generation of the GIF-animation can be trigger with a script:
 * Change to the directory where the images are stored.
 * It might want to resize the images prior to backing the GIF-animation. You can do this with:

mogrify -resize 320 *.png

After the optional step of resizing the images you back the GIF-animation. with

convert -delay 100 -loop 0 img*.png myanimation.gif

Delay time is 100 milliseconds between each frame. Higher number make the animation run much slower. 25-30 frames per seconds is an frame rate for movies. Delay time 100 milliseconds is equivalent to 10 frames per second.