Hradware Design And Implementation Of CMOS Network Camera

With the rapid development of electronic and network technique,security video surveillance system is developing towards networking, highdefinition and intelligent direction. Video analogue cameras, with D1resolution and above400thousands pixels in practical, haven’t met the aboverequirements. Therefore, high definition network camera becomes thetechnique tendency and developed orientation in the field of security industry.So we need to design a high definition network camera to meet the marketrequirement.This thesis taking designing a CMOS high definition network camera asgoal, regarding system framework, circuit design, circuit simulation,component selection and hardware implementation as cutpoint, introduce ahigh definition network camera’s design and implementation course. Thispaper contains3topics:Firstly, image collection unit. Analyze video camera image sensorprinciple, compare the advantage and disadvantage of CCD and CMOS sensor,and select the more appropriated CMOS image sensor (OV2715) as thefront-end image collecting system basing on camera resolution, powerconsumption, integrated extent and cost. The paper uses CMOS image sensor(OV2715) as the front-end image collecting system and resolves theelectromagnetic interference issue during CMOS image sensor A/Dconverting and transmission.Secondly, video signal processing unit. Select Texas Instruments’(TI)TMS320DM368which is video signal processor as video processing platformthrough analyzing the requirement of high definition video coder and decoder technique.DM368supports multi-format high definition video, including VC1,MPEG2, MPEG4, MJPEG, H.264and so forth. Its video output can achieve1080p resolution with30frames per second. Resolves signal integrity ofDM368high speed circuit.Thirdly, system power supply unit. Put forward a solution which can getthe power supply through Ethernet and design detailed circuit schematicaccording to Power over Ethernet system formation in IEEE802.3af standard,that power over Ethernet transmission mode, power over Ethernet course andelectrical characteristics.The hardware system is basing on camera function requirement andmarketing positioning through the research of the above3technique units. Itmainly includes3circuit modules: image collecting module, video processingmodule and power module. The paper introduces schematic design, PCBlayout and final validation test. From the final implementation result, theCMOS high definition network camera can output the video image with1080p resolution resolution with30frames per second through Ethernet alsotake power form Ethernet. The camera’s performance is fully better than theanalogue camera, it also resolve the issue of video networking and highdefinition.