Research And Implement Of The MPEG4 Decode Based On The Intel XScale Embedded System

With the development of mobile apparatus, embedded system has become one of the hotspots now.Embedded system integrated software and hardware together, and characterized by small software code,highautomization,fastresponse,etc.,whichismainlycomprisedofembeddedprocessor,othersupportivehardware , embedded operation system and application, etc. Processor PXA 255, PXA 270 based on IntelXScale architecture has powerful multimedia process ability, and meanwhile adopts unique power savingtechnology, so that while ensuring CPU performance, it farthest reduces the power consumption of mobileapparatus, and suitable for portable apparatus. Meanwhile, because of the rapid development of networkstream media, and emergence of various media format, the public are raising more and more requirementson media player. It is required not only the interface of media player is pleasant and practical, but also themedia player can support media formats as many as possible, especially the currently popular mediaformats.Thepresentsubjectisbasedonthis purpose,multimediaplayerthatcansupportthepopularmediaformat——MPEG4——canberealizedinourembeddedPMCplatform.The main purpose of the present subject is torealize and optimally support MPEG4 decoded media player.thepresent subject is established on the portable multimedia platform that uses PXA255 400MHz microprocessor as acore, and uses embedded Linux2.4.19 as operation system , Qte/Qtopia as graphic user interface. The presentsubject is directed to the detailed requirements of portable multimedia,and realizes the media players of tware andthe realization of MPEG4 decoding on software design.On basis of this,using advanced Intel IPP data base realizesthe optimization of MPEG4 decoding. Moreover, a practical test toolVTune is raised on the optimization of themedia format to help measure the optimizable point in software being decoded,and optimize more effectively.It can be seen from the final test data and conclusion that, the question for study successfully realizesthe design of mediaplayer on PMC, and this mediaplayer can well support the popular video decodingformat MPEG4. After the improvement of MPEG4 decoding, MPEG4 video files can reach 28 frame persecond when played,which achieves a fluent playing.