1. System overview
With the extensive use of network recording and broadcasting system in schools, schools are faced with the problem of all-round recording and live broadcasting of classroom scenes. Because every class needs a special person to track and shoot the teachers’ videos, which is very labor-intensive, it is urgent to solve the problem of teachers’ tracking system shooting teachers’ videos and students’ positioning system shooting students, so as to reduce the work difficulty of staff Degree and workload.
At present, the automatic recording and broadcasting system based on other technologies in the market, in order to complete the automatic tracking process, often uses infrared induction or ultrasonic mode, and uses multiple cameras to switch the shooting area to achieve the so-called tracking. When the teacher walks normally, the phenomenon of picture switching and jumping will appear in the tracking of this technology, which greatly affects the shooting effect, causes the picture to be very unstable, and affects the quality of live broadcast or recording. Because the sensor is used to sense the teacher’s position, it is easy to be interfered by external factors (such as electromagnetic wave, light, sound, etc.), which makes its sensitivity, accuracy and other aspects have great problems. Blackboard content often need to add a separate camera to switch shooting, which wastes a lot of material resources, but can not achieve good shooting effect. In addition, teachers’ tracking and students’ lens positioning often need to wear, use tracking equipment or carry out the whole classroom construction to complete the tracking function, which greatly reduces the practicability of the automatic recording and broadcasting system.
In view of the above situation, after a long time of efforts, Suzhou Xindao intelligent and its partners have successfully used the most advanced image recognition technology to develop the teacher tracking system and student positioning system, which ensure the tracking stability and video effect. In addition, combined with the newly developed intelligent guidance system, the fully intelligent recording and broadcasting system has well solved a series of problems in the previous recording and broadcasting system Problems.
The whole solution of the full intelligent recording and broadcasting system is not only suitable for the course construction of colleges and universities and general education industry, but also widely used in the high standard recording and broadcasting needs of the government, enterprises, institutions and other units as training or meetings.
2. Program objectives
1) Complete the recording of national excellent courses and provincial excellent courses, and establish the curriculum database of excellent / backbone teachers in the school;
2) It is more convenient, accurate and objective for teaching managers to evaluate and compare teaching through network management and monitoring;
3) Build a network platform for mutual observation and reference to achieve the balance of teaching resources sharing;
4) Increase the number of available resources of school network information platform;
5) Establish online learning platform to realize students’ autonomous learning and fully enjoy the best active learning environment with high-quality resources.
3. Scheme composition
The new intelligent recording and broadcasting system mainly completes the automatic tracking and acquisition of teachers’ and students’ video, intelligent audio acquisition, teachers’ computer screen capture, teachers’ / students’ video / computer screen intelligent guiding, and the above signal sources are automatically transmitted to the courseware real-time recording system to generate high-quality fine courses. At the same time, the classroom live broadcasting system is used to broadcast on LAN and Internet for remote users A platform for online real-time learning.
The whole system is divided into six subsystems
（1） Recording and broadcasting central control system
Features: after redesigning the recording and broadcasting console, the degree of integration is further improved, one key on / off system, one key to start / stop recording and broadcasting, teachers can teach without any technical training; The new version of the console provides the traditional button operation, and also provides digital touch operation, which can control the pan tilt lens, conduct the manual broadcast, and track the mouse click, etc.
（2） Image location system
Image positioning system is divided into two subsystems: teacher tracking system and student positioning system.
2.1 teacher tracking system
Features: the teacher tracking system has outstanding tracking performance. Whether the teacher is walking fast in class or writing on the blackboard, the system can accurately use different strategies for automatic zoom tracking shooting. The whole tracking process is continuous, stable and smooth, and the picture output is very stable. The system completely adopts the unattended operation mode, and the whole tracking process does not need human intervention. The teachers only need to carry out normal teaching activities according to the normal teaching mode, and do not need to wear special tracking equipment to complete the tracking shooting, so as to eliminate the teachers’ sense of maladjustment and make them more focused on teaching activities.
2.2 student positioning system
Features: the student positioning system can automatically locate the students who are speaking in real time and take close-up photos. When the students stand up to speak or answer questions, the student positioning system will automatically call the student camera to locate the students who are speaking and take close-up shots. After the students finish speaking, the system will automatically return to the teacher tracking system.
（3） Intelligent guide system
Features: the intelligent guiding system integrates the guiding function of the traditional automatic recording and broadcasting system and the special effects switching station function. It is mainly used for automatic switching between multiple scenes and multiple video signal sources, video / audio files and computer pictures in the course recording process. The system intelligently selects the switching strategy with the change of teaching activities, and realizes the intelligent guiding with special effects;
（4） Intelligent audio system
Features: the intelligent audio system mainly realizes the voice signals of teachers’ teaching and students’ answering questions or discussing in class, which are collected by the intelligent mixer hologram and transmitted to the courseware recording system in real time to complete the courseware real-time recording;
（5） Courseware real time recording system
Features: it is very simple and convenient to record the whole classroom scene in real time and generate streaming media courseware with audio and video and electronic documents. And the compression rate is very high, can achieve dynamic capture, automatic generation of text index and other functions.
（6） Composition of classroom live broadcast system
Features: through IP network, such as local area network, Internet, satellite network, the classroom content can be broadcast directly. The classroom content includes audio, video and computer screen content. The receiving end can watch the live classroom content through IE browser.
Editor in charge: GT