There are many "spy" cameras built into sunglasses available cheaply, and many miniature "spy" transmitter cameras built into all kinds of things, so it is obviously simple for a suitably qualified and knowledgeable electronic technician to combine the two devices. Or very likely, it has already been done and can be bought very cheaply from China.
It might be a more educational approach to use webcams or your own smartphone and learn how to stream digital video content using possibly somthing like div x or java media framework or avicap32.dll which will enhance or progress you to a more modern approach with respect to technology rather than just accepting its a camera, providing are far widened interesting approach to modern day security Ip cameras and their use, applications with respect to the internet
You can even write some of this with just ordinary easy to understand Ms Visual basic Ver6 and further enhance this to include embedded engineering system eg motor control for panning the camera capturing the sound and writing to files at the same time
