The Research Of Video Signal Capture And Processing Technology In Micro-teaching System

Micro-teaching is widely used in psychology, education, academic teaching, teachereducation and other fields. Micro-teaching which absorbes a lot of advanced teaching ideas andconcepts has played a very important role in improving the quality of teaching, especially teachingskill of normal student. The continuous development of modern information technology andmultimedia technology provides development opportunities for schlools for the realization ofintelligent teaching equipment, education management modernization and diversification teachingmethods. Computer network technology, embedded circuit technology and audio-video technologywill be applied to the micro-teaching system, which builds a good platform for effective teachingskill training and provides modern methods for teaching process feedback and teaching evaluation.Base on the research of DirectShow streaming media processing platform, H.264/AVC videocoding technology and multi-channal video encoding chip SC8919which includes H.264hardwarevideo encoder. This thesis designs the video signal processing system which used in micro-teaching interactive multimedia teaching with the function of multimedia classroom teaching,multi-channel video recording and storage. It can compress four channel D1(720*576) size of theimage data collected by camera at the rate of30fps into standard H.264stream and upload it to thecontrol room to store and decode broadcast. Rely on the existed campus Ethernet platform fortransmission without additional laying line. The terminal can adopt friendly operating interface anduser-friedn operation. Through the actual operations and the debugs, the technical indicators haveachieved the design requirements.This paper proposes the overall design scheme of the system based on the analysis of thesubject’s siginificance, including video capture module, PCI data interactive bus modules, videoserver module and the network transmission module. Then it describes the H.264/AVC videocoding standard and DirectShow streaming media processing platform in detail. Secondly, thepaper completes the video capture module design in the core of SC8919. At the same time, thefunction and the application of main chip in the module are discussed. Then, introducing the designof the video server, this part is based on the full research of the use of the SC8919chip’s internalresource. The design of multi-threaded design, system initialization, DirectShow filter and system interface are given in detail. And describe the process of software and hardware debugging. Finally,the paper describes the design process of netrwork transmission module.