I gave the Slit Cam program a quick try. This was a video of a Monarch caterpillar pupating, there's a still image on the right and the full video is below for reference. It's 5 minutes and not very exciting unless you've never seen this sort of thing before or just find insect metamorphosis fascinating. There's no cheery or uplifting music to keep you entertained. If you sit through it, you're not allowed to ask me for your 5 minutes back
.
The top left is taking a vertical 'slit' running through the centre of the video (straight through the cremaster). The leftmost column of pixels is this slit at the first frame, the rightmost column is this slit at the last frame of the video. As time marches to the right, we can see how the last instar's larval skin is drawn upwards. There is much bobbing up and down during the process making the waves
. It's kinda neat how it gives you a measure of the frequency of this bobbing during the transformation.
For the bottom left, I took a horizontal slit about 1/3 from the top of the video. This captures the skin from the last instar as it's sucked towards the top and passes by the 'slit'. Near the end, the pupa is bobbing up and down enough to get above the slit, and then it settles down. It's rotated sideways 90 degrees.
I have to say, this is a pretty fun way to represent a literal slice of a video into a single 2-d, static image.