NEC have developed a technology that, they claim, will cut out zoom lens and auto-focus motor noise during video recording. The system uses a microphone and DSP that generates "pseudo-noise" to cancel out background buzzing from the camcorder's own hardware; the advantage of a predominantly software system is that it can be fitted to even the smallest of point-and-shoot camcorders and video-capable digital cameras.
As well as ongoing, steady noise from hardware, the system is apparently capable of cutting out intermittent or unexpected sounds, such as noise from the cylinder lens or mirrors. In fact it's even clever enough to take into account the ageing of motors and tweak the "pseudo-noise" accordingly.
NEC will be showing off the technology in Japan this week, and they're hoping to develop a consumer version of the noise-cancellation system for inclusion in commercial products. The end result will mean recordings that only pick up the audio you want them to, rather than being drowned out by auto-focus and zoom noise.