The Collection Drive AVStream Architecture-based TV Design And Implementation

The release of Windows MCE operation system offers a platform for the develop ment of digital home. Meanwhile, its application needs the support of software and also hardware. Device driver program, as a bridge, connects the application software, hardware devices and operation system. The key point of the utilization of media center is the processing of multimedia data stream. Microsoft provides kernel streaming for the audio and video data stream in the operation system. While, the traditional port class driver and the stream class driver only process the audio and video stream respectively in the kernel streaming model, and it is not good at supporting the DirectShow software interface since the properties setting is very complicated. The new generation of AVStream class driver model has inherited much advantage from the WDM architecture; it not only provides unified kernel streaming for the audio and video stream, but also adds the device property control through COM component for use-mode application software without changing any driver binaries. Meanwhile, it supports the future digital broadcast TV device. Therefore, it is not doubt to say that the new generation of AVStream driver is a very promising technology.This thesis, based on the research and design of AVStream driver, firstly introduces the background of the development of stream based driver, including WDM, Windows operation system kernel streaming principles and the hierarchical relationship with data structures among AVStream driver model. Then, the broadcasting audio and video decoding chip and MPEG-Ⅱencoding chip for TV capture card are illustrated. The design and realization for AVStream minidriver program deployed in PCI interface TV capture card is completed, which includes the communication methods and loading steps between firmware and driver program, the initialization of minidriver and hardware devices, DMA control of driver and the interrupt service programs, the creation and description of AVStream devices, filters and Pin objects. The explanation of all property control functions for each filter is also contained in the thesis. Afterwards, demonstrates the programming of INF files for TV capture card driver and the installation procedure of the driver. Finally, a comprehensive test for designed driver program is applied. The video capture graphs generated in GraphEdit verify the functions of each filter and driver's designed property settings. The driver program's compatibility is also proved by HCT tool in this thesis.As test results showing, the functions of designed driver program are accomplished, the user-mode applications can easily access the controlling properties which are exposed by the driver; the compatibility with Windows operation system and other hardware devices are satisfied, only the performances of VBI signal processing and control are not good enough and need to be improved in the future works. Currently, designed driver is adopted by some company with a great impression.