The Video Codec Research And Application Based On I.MX27

In recent years, with the rapid development of information industry, we use Internet more and more often in our daily lives. It has become an integral part of our lives. With the development of Internet technology, especially with the increase of the bandwidth and the reduction of the cost, the products which are Internet-based become more and more rich, and the Internet users are increasing. The ubiquitous wireless network takes the embedded terminal more prominent advantages:First, as the advantage of the technology and the maturity of the embedded hardware platforms, the mainstream frequency of CPU which used in embedded devices has reached or exceeded 1GHz. With the growing maturity of memory, large capacity storage devices are increasingly used by us. It means that the embedded terminal has no bottleneck in the system performance. The advances in technology makes cost low. So, the embedded terminal has more better cost-effective. Second, the rapid development of wireless networks makes the requirement of portability increasing, but this is the unique advantage of the embedded terminal.This article describes a video processing solution for the embedded terminal. The program is based on the iMX27 chip which is developed by Freescale. The chip integrates a central processing and a image codec. It greatly meets the needs of the image encoding and decoding, and improve the ability of the image codec. In this paper, we made the programming process of using iMX27 in detail. The program is based on an open source software which can use audio and video communication, it is called Linphone. It has many advantages such as powerful and easily transplant. In addition, the system platform of the program is based on the Linux operating system. It has many advantages such as open-source and easily transplant. So it becomes the mainstream embedded operating system. In addition, the details of the V4L2 programming are also elaborated in this paper. This technology is used in video processing under Linux, including video capture and video output. The video coding technology has been applied to the Linphone the system, and eventually the video communication is implemented. And in this paper, a graphical interface tool which is used in Embedded Terminal has been introduced. It is called MiniGui. Users can use this tool to control terminals.The architecture of the Linphone, the principles of the V4L2 programming and the iMX27 programming process are elaborate in this paper. The details of that the V4L2 programming and the iMX27 programming process are ported to the Linphone are presented in this paper. And finally, the video communication is implemented. This paper has significance in the field of VOIP.