animated gif out and back loop, backwards, forwards animatio

[danpaluska]

i've used this command and it works great.
convert -delay 20 -loop 0 foo*.gif animatedfoo.gif

so if i have foo1, foo2 ... foo20, then i get a 20 frame movie. this is great if frame 20 lines up with frame 1 but what if not?

i would like to go 1 to 20 and then go back to 1. so a 39(or 40) frame animation.
or 1,2,... 19,20,19,18 ... 3,2,1.

some subtlety in the turnaround frames but i think it's easy to see the basic idea.

is there a way to make this happen easily in a single command line? or do i need to copy and rename files? or some other magick?

thanks!

boranj,
dan

[anthony]

You want a patrol-cycle. Like a guard on patrol.

See Im Examples, Animation Modification, Reversing Animations
http://www.imagemagick.org/Usage/anim_mods/#reverse

[danpaluska]

thanks!