Garden Video Camera Switcher

This is a project for home use. We have a number of (analogue) video cameras in the garden and they are used for looking at wildlife such as inside bird boxes and also for looking at hedgehogs. The routing of all of the cables is quite challenging and to get around this I am moving the multiplexing of the video feeds into the garden under control of a Raspberry Pi. The interface will be web based and only the selected feed will then be sent into the house - this will considerably reduce the amount of cabling required. There are going to be five boards in total, I have ordered three to date and these are shown in the attached pictures. The main technical challenge is going to be getting the Raspberry Pi to work in read only memory mode so that the unit can be turned off without warning. The boards themselves are very high quality and I will certainly be using PCBWay again!

Step 1: Control Logic

First steps will be to ensure that the hardware works in conjunction with the Raspberry Pi software being developed. 

The key measure of success is going to be the quality of the video, the digital noise from the Pi should be kept away from the video by the use of opto isolators.

Step 2: Settings Retained

Because the Raspberry Pi is operating in read only mode, the settings for this switcher will be stored on a remote server and accessed via a REST API. This step will be get that working in a reliable fashion.

Step 3: Design Remaining Boards

Two further boards still to be ordered from PCBWay, one is a card to switch audio, it will reuse a lot of the design from the video card that I have already received. The other board has power regulators on it that are switched on and off as required for the camera in use.