Achieving Video Stream Synchronization
For these system designs, camera synchronization can become a challenge. Processing time of each camera can vary due to component tolerances or even conditions in the visual scene being recorded. Time stamp mechanisms would need to be introduced in software to overcome the problem. However, additional software would further utilize the vision processor. As a solution four hardware features are discussed as follows ensuring frames from all video streams arrive in the vision processor at same time. No additional software engagement would be required.
Back Channel Technology
The SerDes integrated bidirectional control channel transfers data over the same cable. It eliminates the need for additional wires for programming the image sensors’ registers via I2C. The bidirectional control channel also allows controlling GPIO pins of the SerDes chips in both directions. Commonly, this is used to send frame sync trigger pulses from the central processing unit into the image sensors for synchronization. Concurrently, it can carry status signals from all image sensors and pass it on to the central processing unit for monitoring purposes. The bidirectional control channel can also carry a central system reference clock from the deserializer to each camera serializer.