Design and implementation of the video detecting and recording system on DSP

A compact video processing system which deals with video detecting, compressing and recording is designed on DSP. And in order to find a balance among hardware resources (prime cost), processing speed, detecting performance, system stability and system reliability, further algorithm and processing mechanism optimizations are proposed. This system does automatic surveillance of an unattended area installed fixed video camera, which automatically detects and locates moving objects, sends alarm message, compresses and records the video of the scene. The DSP core does the moving object detecting first, then starts sending alarm message and recording according to the results. As for video detecting, a fast and reliable moving object detecting algorithm is designed. This algorithm is based on principles of temporal differencing and background subtraction algorithm. Thus on one hand the system can make reliable alarm determinations. On the other hand, it is robust when there is light interference or sudden background change. As for video recording, SDHC card is chosen to be the storage device. Because it is pluggable and portable, SDHC card is very suitable for a compact system. The compressed video data will be stored in the card in FAT32 file format through SPI bus. Considering the automation and remote control of the system, GPRS wireless module is used to send multi-media alarm messages to the user. Long time experiment results demonstrate that the system can capture the moving object in an unattended area effectively, send alarm message to the remote user, and be robust when the light or the background changes.