ONVIF Specification Introduction

onvif Specification Chinese IntroductionCategory: IPNC product design 2012-11-08 14:54 16393 People read review (5) Favorite Report

Directory (?) [+] What is the implementation mechanism of the ONVIF ONVIF Specification onvif specification of the content of the project based on the ONVIF specification what is ONVIF?

The ONVIF specification describes the models, interfaces, data types, and patterns of data interaction for network video. and re-used some existing standards, such as the WS-Series standards.
The goal of the ONVIF specification is to implement a network Video framework protocol that allows for complete interoperability of network video products produced by different manufacturers, including recording front end, video recording equipment, etc.

The ONVIF specification describes the models, interfaces, data types, and patterns of data interaction for network video. and re-used some existing standards, such as the WS-Series standards.
The goal of the ONVIF specification is to implement a network Video framework protocol that allows for complete interoperability of network video products produced by different manufacturers, including recording front end, video recording equipment, etc.

The interfaces defined in the Device Management and Control section of the ONVIF specification are provided as Web services. The ONVIF specification covers the full definition of XML and WSDL. Each terminal device supporting the ONVIF specification must provide a Web Service corresponding to the function. The service side interacts with the client's data using the SOAP protocol.
Other parts of the onvif, such as audio and video streams, are performed through RTP/RTSP.

Synergy: The products offered by different manufacturers can be communicated through a unified "language". Facilitates the integration of the system.
Flexibility: End users and integrated users do not need to be constrained by the inherent solutions of certain devices. Greatly reduces the development cost.
Quality Assurance: The constantly expanding specification will be guided by the market, follow the norms and also meet the needs of the mainstream users.

Due to the use of Wsdl+xml mode, the subsequent extension of the ONVIF specification will not encounter too much trouble. The very strong extensibility of XML and the ease of development of the SOAP protocol will attract more people to focus on and use the ONVIF specification.
Onvif's organization is growing, occupying an absolute advantage over the PSIA,HDCCTV in the same field. Member companies are not lack of well-known domestic and foreign equipment manufacturers and integrators. A set of norms, the life cycle of the agreement, and market share is closely related. and the development of onvif norm is to be driven by the market, by the user to enrich. Each member enterprise has the right to strengthen and expand the onvif norms. The areas covered by the ONVIF specification will continue to grow. At present, the related content of access control system will be included in the ONVIF specification.
In the rapid development of security, monitoring systems today, the efficiency and quality of the lead brought about by the value of self-evident. The ONVIF protocol provides such potential.
implementation mechanism of ONVIF specification

1. Web Service

2. wsdl

3. Soap

Web Service is a network-based, distributed, modular component that performs specific tasks. Web Service primarily leverages HTTP and SOAP protocols to make data transport over the Web. Web users can invoke remote objects using SOAP and HTTP through the Web call method.

The client describes the document according to the WSDL and generates a SOAP request message that is embedded in an HTTP POST request and sent to the Web server on which the Web Services resides. The Web services request processor resolves the received SOAP request and invokes the appropriate Web services. The corresponding SOAP reply is then generated. After the WEB server receives a SOAP response, it sends the message back to the client in the form of an HTTP reply.

WSDL is the abbreviation for the Web Services Description Language (Web Service Description Language). is an XML language that describes Web services and describes how to communicate with Web services, providing users with detailed interface instructions.

SOAP is an abbreviation for simple Object Access protocol. is an XML-based protocol. A SOAP message is a plain XML document that contains the following elements:
Required Envelope element to identify this XML document as a SOAP message
Optional header element with header information
Required Body element, including all call and response information
An optional Fault element that provides information about the error that occurred while processing this message
In a SOAP request sent to a Web service, the fields in the body element should conform to the data type in the WSDL. In the process of building soap, this correspondence must be fetched and mapped from the WSDL file. However, such a correspondence process will be full of repeatability and mechanical, in order to avoid unnecessary artificial errors and save development time, a compile tool called gSOAP came into being.
gSOAP uses compiler technology to provide a transparent set of soap APIs and hides content related to the development-agnostic SOAP implementation details to the user. The development of Web service is minimized by parsing the WSDL file into a C + + file.

Web Service Development process

WEB Service and video surveillance

The ONVIF specification introduces the concept of Web service to video surveillance. The actual function of the device is abstracted for the service of the Web service, the control unit of the video monitoring system appears as the client, and the control operation is done through the Web request.

What Web service can bring to a video surveillance system.
Device independence, any one device access system, will not affect other systems.
The independence of the device, each device is only responsible for connecting to the received request to make feedback, even do not need to know the existence of the control side.
The centralization of management, all the controls are initiated by the client.

What the ONVIF specification can bring to a video surveillance system.
An interface that abstracts functionality. Unifies the configuration of the device and how it operates.
The control side does not care about the model of the device, but the web Service provided by the device
The behavior outside the scope of the Web service in the video system is regulated.
The ONVIF provides WSDL for each module and has a very efficient development approach.
content of the ONVIF specification

Device Discovery
Device Management
Device input/Output service
Image configuration
Media configuration
Live Streaming media
Receive-side configuration
Display Service
Event handling
PTZ Control
Other
development of a project based on ONVIF specification