Posts Tagged‘rolling shutter’

Soundwaves and Synched Video.

With CGI being par for the course these days any you can’t be blamed for thinking that anything you see is fake. I think that’s why effects that are achieved without the use of computer trickery are so impressive, much in the same way as games that forego modern graphics but still manage to create an intriguing experience. Probably one of the coolest effects I’ve seen recently is the use of sound waves that are at a very similar frequency to the frame rate of the camera being used which ends up producing some pretty weird and wonderful effects.

Below is the latest one I’ve come across, and it’s pretty awesome:

As the video alludes to the effect would appear to stem from the rolling shutter that CMOS based cameras use to create images. What’s happening is when the image is read off the sensor its done line by line and then reconstructed into a full image. However because of the way the sensor is read this allows the image to change during exposure which gives rise to all sorts of weird and wonderful effects. In this particular video it has the effect of making the speaker cone appear to have a wave travelling through it, rather than it slowly moving in and out like the creator expected. This has since been confirmed in other videos as rotating the camera¬†shows the effect tracking the camera’s point of view.

Other interesting effects you can get is “freezing” the motion of water using a similar technique. If you fool around with frequencies slightly you can also get all sorts of other weird behaviour like water appearing to defy gravity.¬†These are all based on sound waves however but anything that has a periodicity to it will allow you to make some really cool effects with cameras that use a rolling shutter.