Study On Enhancement Of Passenger Information System Performance Based On Multi Layers

PIS(Passenger information system)is a multimedia integrated information system for passengers to get train information and public media information timely and accurately by setting the display terminal on station hall,platform,entrance and train.The cores of PIS are multimedia network technology and computer technology.PIS system has become an important way of information transmission.It is important to find different ways to improve the performance and stability of PIS system.In order to improve the performance of PIS system,we analyzed the relative factors of PIS system performance.According to these factors,we studied how to improve the performance of PIS system by multi layer module design based on SMP8756 multimedia chip,which provides hardware graphics acceleration.In order to implement the function of PIS system,we also studied the method of porting Qt and DirectFB in SMP8756 multimedia chip system and developed the function of PIS terminal display system via the joint development of Qt and DirectFB.In this thesis,three different designs are devised with different development techniques and ideas.We put forward the multi layer design based on the analyzation of the main defects of the single layer.Via the comparison of the performance between single layer design and multi layer design,we confirmed that the performance of PIS system in multi layer design is better.Then to dispose of the poor applicability and the poor expansibility,we came up to the interface design by analyzing the problems in the first two schemes.In this thesis,we implemented a typical embedded development project with a general method of embedded development and studied the porting method of development library in embedded environment.In this thesis,we also put forward designs to improve the performance of PIS system and had the designs tested.Via these designs,we provide good ideas for the relative development of PIS system.