Design And Implementation Of Embedded Landscape Lighting Multifunctional Controller

As an effective method to enhance image of city and display cultural heritage of city,landscape lighting plays an important role in urban lighting projects.In recent years,with the vigorous advancement of urban lighting,landscape lighting has broken through traditional lighting modes of points and lines,and developed into flat and stereoscopic lighting.Large-area,high-density LED lighting arrays have become a research hotspot.However,traditional large-scale landscape lighting control system has two defects.First,it mainly relies on general purpose computer and special software during video playback.Second,monomer management mode limits expansion of system,which cannot work for unified management and real-time monitoring of large-scale landscape lighting.In order to solve these problems,this thesis investigates and designs a landscape lighting multifunctional controller based on embedded computer and “cloud + end” IoT platform.The main work of this thesis includes:(1)To meet the demand of HD video decoding,video image customization output,end-to-end communication,video storage and update of large-scale landscape lighting,a design scheme of landscape lighting controller using embedded computer instead of general purpose computer and peripheral equipment is proposed.Taking R58 processor as the core,the hardware circuit is designed and the embedded Linux operating system is transplanted,which provides a platform for the development and operation of landscape lighting business functions.(2)Mpv,a lightweight video player is ported and customized to realize video decoding and playback in multiple encoding formats and package formats.The VDPAU-based hardware acceleration of video decoding is studied and implemented.R58 hardware decoding engine replaces CPU to undertake computationally intensive video decoding tasks,which greatly improving the performance of video decoding.In response to video output requirements of various sizes,mpv is customized and extended to realize video image rescaling and colorspace conversion with multithreading,and its video data is going through Gigabit Ethernet and HDMI port.Without the assistance of the general purpose computer,landscape lighting controller can decode,play and output HD video independently.(3)Based on MQTT protocol and JSON format,M2 M communication model and data format is developed.Landscape lighting controller is connected to IoT platform,and established end-to-end instant and reliable remote communication with cloud platform and users.It realizes centralized management and real-time monitoring of widely distributed on-site lighting system.Based on the M2 M communication,online editing and management of program list and end-to-end remote video transmission with HTTP is implemented to provide users with remote services such as video and program management of landscape lighting controller.The landscape lighting controller designed in this thesis has ability of video playback independently and remote unified management.It can solve the above major problems of the traditional large-scale landscape lighting control system and realizes the intelligent transformation of the system.It will effectively broaden application scope of landscape lighting and promote innovative development of China's large-scale landscape lighting industry.