Animated wipes with ImageMagick
To generate the animated GIF of a smooth wipe between these two images, I used the
convert command from ImageMagick:
convert \ -loop 0 \ -delay 5 \ image1.jpg \ \( image2.jpg -crop 10x0 \) \ \( -clone 0 -crop 10x0 -reverse \) \ output.gif
-loop 0 -delay 5 says to loop forever and to delay 50 ms between images, which is 20fps.
-crop 10x0 controls the wipe speed and direction. This wipes 10 pixels in the X direction and none in the Y direction. If you want to wipe top to bottom, use
-crop 0x10. If both an X and Y are specified it does a checkerboard wipe that doesn't look as good.
-clone 0 reuses the first frame and the
-reverse makes the wipe go right to left.
The label overlays were also added with ImageMagick - this could be done as part of the animation command if you wanted to avoid creating temp files:
convert \ -fill white \ -background '#0008' \ -geometry +800+20 \ -size 100x50 \ caption:'2009' \ image1.jpg \ +swap \ -composite \ image1-label.jpg