Research And Application Of Synthesis And Synchronization Playback Software For Audio And Video In Passenger Emergency Communication

With the continuous development of national economy, urbanization process in China also gradually speeds up. Along with the economic development and increasing vehicle, the urban road traffic system is facing an unprecedented challenge. Developing the underground transportation is urgently needed to relieve the pressure on urban traffic congestion. With the advantage of large capacity and less space occupied, more and more subways are constructed in large and medium-sized cities, and it has become the best solution to the urban traffic problem.Closed space, crowded passenger compartment and huge mobility become big threats to the subway operation safety. In today’s vehicle video monitor system, the passenger emergency communication mechanism is mostly introduced. When there are emergency cases in the passenger compartment, passengers can use the PECU alarm to establish connections with the driver, helping drivers and operating managers acknowledge the emergency in the passenger compartment in time to minimize the effects of the emergency. At the same time in order to define the accident responsibility, the video images in the corresponding passenger compartment and the audio data of PECU alarm calls should be recorded. But for passenger emergency communication at present, there are problems such as the large environment noise, unclear audio data and the problems caused by the separate storage of the video and audio data.Aiming at these problems, the synthesis and synchronization playback software for audio and video in passenger emergency communication is designed and implemented in this thesis. The software can not only ensure to obtain PECU alarm video data and audio data clearly and accurately, but also can solve the problem caused by the separate storage of the video and audio data. Firstly based on passenger emergency communication mechanism, the functions which the software should realize have been analyzed. Then according to requirement analysis and the actual operation platform, the software is divided into NVR parts which will run on a Linux platform and BSClientXP software parts which will run on a Windows platform. The both are divided into multiple functional modules to design implementation separately. Finally a test environment is set up to test each functional module one by one, ensuring that the software meets the needs of the passenger emergency communication and the safety of subway operation. The software has been applied to lots of subway projects at home and abroad, and the actual running effect is satisfactory.