Design And Implementation Of A Low-cost And High-definition Digital Undercover Camera

Undercover camera is of the kind of digital camera equipment which can record audio and video data of the real scene of the incident without the knowledge of the relevant people, widely used by detectives and repoters to investigate and evidence gathering. Currently appearing undercover cameras are mostly adapted from the home-used or professional cameras, and have many disadvantages, such as not conducive to covert operations, poor environmental applicability and high cost. Developing a compact, easy to operate, low-illumination, low-cost and high-definition cameras become the universal needs of many users.Based on analysis of the market demand for undercover cameras, this thesis designed and implemented a high-definition and low-illumination digital cameras. The main work completed included:(1) Based on comparison and analysis of the mainstream undercover camera design scheme, this paper prsented the overall design scheme of the camera to the design, including hardware design and software design.(2) Based on the hardware design scheme, the design principle diagram of camera hardware system was presented, and the principle component of the hardware system, including DM368microcontroller, sensor and ISP circuit, power supply circuit, DDR memory circuit, FLASH memory circuit, NAND TF card storage circuit and WIFI interface circuit, ware analyzed and designed in detail.(3) Builded the embedded software development platform, including the Linux based software architecture, device drivers, and the application software layter of the camera. The design and implementation of android applications on mobile phone terminal was also presented.(4) Set up the testing environment, and the function of the camera was verified through the actual application.Undercover camera designed in this paper has the advantages of high definition, low illuminance, low cost, easy to control, and the video resolution is:1080p@25f/s, photographic resolution can reach5megapixels, low illumination effect can reach0.1Lux, the volume is less than1.5cm*5cm. Continuous recording time of the camera is of up to1hours or more, and can be controlled throuth an app of a android operating system based mobile phone. The good practicability, reliability and low cot of this camera make it favorable at the market.