Design And Implementation Of Embedded Streaming Media System Based On RTMP Protocol

With the development of communication technology,especially the maturity of multimedia transmission technology,people have increasingly diversified ways to obtain audio and video information.Among them,streaming media transmission is a technology that has attracted much attention.Compared with downloading files,which is a traditional method,streaming media technology reduces waiting time and saves storage space.At present,streaming media systems are generally deployed on servers and clients on the PC side.In contrast,embedded devices have the advantages of high flexibility and high reliability.This thesis innovatively applies RTMP protocol and streaming media technology to the embedded digital TV front-terminal equipment.The hardware platform of the system is based on ARM9 embedded processor,real-time transmission of audio and video data through RTMP protocol,users can forward through the server.The way to obtain multimedia information,you can also directly transfer data through peer-to-peer.After testing,the system has the advantages of wide application scenarios,low power consumption,and reliable transmission compared with the traditional streaming media system.The embedded streaming media transmission system studied in this thesis is divided into three parts:the transmitting terminal,the streaming media server and the receiving tenninal.The transmitting terminal and the receiving terminal adopt the embedded digital TV front-terminal equipment,and the transmission protocol uses the RTMP protocol.There are two main ways of transmission.The first is that the sender is responsible for processing audio and video data and pushing it to the Internet.The streaming server pulls and forwards from the network,and the receiving terminal receives the data forwarded by the server and performs the next processing.The second transmission mode is a peer-to-peer mode,and the transmitting terminal and the receiving terminal directly perform transmission based on the RTMP protocol,and are not forwarded by the streaming media server.The subject has two innovations in design and technology implementation:First,the RTMP protocol is applied to the embedded device field,and the peer-to-peer transmission mode that does not depend on the streaming media server is realized,the application scenario of the RTMP protocol is extended.Second,the implementation of the RTMP protocol for transmitting TS stream files enables the RTMP protocol to be applied to the field of digital television transmission.The main work of this thesis has the following items:1.The system environment is built,mainly including the establishment of software and hardware platforms at both terminal of the sending and receiving,and the construction of streaming media services.2.Program implementation of RTMP protocol,using C language to realize initialization of RTMP protocol,protocol handshake,data transmission,etc.3.the program is transplanted to the embedded platform,mainly including cross-compilation and transplanting the program to the embedded device.4.The realization of the network management system mainly includes the design and implementation of the RTMP parameter adjustment interface and the addition of the RTMP parameter adjustment function in the existing network management system.After testing,the system realizes streaming media transmission based on RTMP protocol on the embedded platform,which is stable in operation and good in image quality,and can meet the streaming media transmission requirements of embedded platforms such as digital TV front-terminal devices.