Onvif Network Camera development (1)

Onvif:

Onvif specifications describe network video models, interfaces, data types, and Data Interaction modes. And reuse some existing standards, such as the WS series standards. The onvif specification aims to implement a network video Framework Protocol, so that network video products (including video recording front-end and video equipment) produced by different manufacturers are completely interconnected.
The interfaces defined in the device management and control section of the onvif specification are provided in the form of web services. The onvif specification covers the full definition of XML and WSDL. Each terminal device that supports the onvif specification must provide a web service that corresponds to the function. The Data Interaction Between the server and the client adopts the SOAP protocol. Other parts of onvif, such as audio and video streams, are implemented through RTP/RTSP.

Specific reference Encyclopedia: http://baike.baidu.com/view/3038937.htm? Fr = Aladdin

Web Services:

Web services are published, searched, and used through the Web..Application components communicate using open protocols. They are independent (self-contained) and can be self-described. They can be discovered by using UDDI and can be used by other applications. XML is the basis of Web Services.

How Web Services works

The basic web services platform is XML + HTTP.

HTTP is the most common Internet protocol.

XML provides a language that can be used between different platforms and programming languages.

Elements of the Web Services Platform:

Soap (Simple Object Access Protocol)

UDDI (General description, discovery and integration)

WSDL (Web Services Description Language)

The following is a basic process for a Web service client to call web service.

--> Construct a SOAP request message (convert a local data object to a SOAP message)

--> Send the SOAP message to the specified port of the Web Service Server

--> Receive soap response messages

--> Converts a soap response message to a local data object

3. Relationship between WebService and SOA

WebService is a specific implementation of SOA.

SOA is an idea

Just like the relationship between object-oriented and J2EE

4. HTTP-based soap transfers XML files under the HTTP protocol

5. UDDI: discovery and integration of services, rarely used

6. Development Method: you only need to obtain the WSDL method.

7. Slow WebService Efficiency

Transmitted text

EJB and CORBA transmit binary data with better efficiency

8. Intercept SOAP request and Response Information

Specific reference Encyclopedia: http://baike.baidu.com/view/67105.htm? Fr = Aladdin

RTSP (Real Time Streaming Protocol ),

Rfc2326 is an application layer protocol in the TCP/IP protocol system. It is an ietf rfc standard submitted by Columbia University, Netscape and RealNetworks. This Protocol defines how one-to-multiple applications can effectively transmit multimedia data over an IP network. RTSP is located on RTP and RTCP in the architecture. It uses TCP or RTP for data transmission. Compared with RTSP, HTTP requests are sent by the client and the server responds. When RTSP is used, both the client and server can send requests, that is, RTSP can be bidirectional.

Specific reference Encyclopedia: http://baike.baidu.com/view/70534.htm? Fr = Aladdin

SDP:

Session Description Protocol. Multimedia session description is provided for session notifications, session invitations, and other forms of multimedia session initialization.

Specific reference Encyclopedia: http://baike.baidu.com/view/875414.htm? Fr = Aladdin

RTP:

RTP (Real-Time Transport Protocol) is a network transmission protocol, which was published by IETF's multimedia transmission team in RFC 1996 on April 9, 1889, and then update it in rfc3550.

Specific reference Encyclopedia: http://baike.baidu.com/view/1268656.htm? From_id = 8974125 & type = SYN & fromtitle = RTP & Fr = Aladdin

H264:

H. 264, also Part 10 of MPEG-4, is a joint video group (JVT, Joint Video Team) composed of ITU-T video coding Expert Group (VCEG) and ISO/IEC dynamic image Expert Group (mPEG) the proposed high compression digital video codecs standard. This standard is generally called H. 264/AVC (or AVC/h. 264 or H. 264/MPEG-4 AVC or MPEG-4/h. 264 AVC.

Detailed introduction reference Encyclopedia: http://baike.baidu.com/view/56322.htm? Fr = Aladdin

Understanding the above basic knowledge helps you understand the entire architecture.

Onvif Network Camera development (1)