基于AVStream架构的电视采集驱动设计与实现

【作者】 何泽生；

【导师】 李广军；

【作者基本信息】 电子科技大学 ， 信号与信息系统， 2007， 硕士

【摘要】 Windows MCE操作系统媒体中心的发布，为数字家庭的应用提供了平台。同时，它的应用还离不开软硬件的支持，设备驱动程序作为连接应用程序、硬件设备和操作系统的桥梁，把它们紧密联系在一起。多媒体数据流的处理是媒体中心应用的关键，微软为操作系统处理音视频数据流提供了内核流的支持，但传统的端口类驱动和流类驱动在内核流模型下只能分别对音频或者视频流进行处理，且对上层的DirectShow软件接口支持并不理想，属性设置较为繁琐。新一代的AVStream音视频流类驱动继承了WDM驱动架构的诸多优点，不仅为音视频提供了统一的内核流支持，驱动程序还可以通过COM组件为用户层软件增添设备的属性控制而无需修改任何驱动代码，与此同时，它还提供了对未来数字广播电视设备的支持。因此，新一代的AVStream音视频流类驱动具有很大的发展潜力。本论文以AVStream驱动程序的设计和开发为线索，首先介绍了流式驱动程序开发的技术背景，包括WDM驱动模型，Windows操作系统的内核流原理以及AVStream音视频流类驱动对象的层次关系和数据结构；然后，简要介绍了电视采集卡使用的音视频解码芯片和MPEG-Ⅱ编码芯片。本论文完成了对PCI接口的电视采集卡AVStream微驱动程序的设计和实现，其中包括Firmware与驱动程序之间的通信机制及加载流程，微驱动和硬件设备的初始化，驱动程序的DMA控制，中断服务程序，以及AVStream驱动的设备、过滤器和Pin对象的创建与描述，并说明了各内核过滤器的属性控制函数的设计。最后，本论文编写了电视采集卡驱动程序的INF文件；并对本设计的驱动程序进行了全面的测试。除在GraphEdit可视化环境中创建视频捕捉图表，验证驱动程序各过滤器的功能和属性设置能力外，还使用HCT工具对驱动程序的兼容性进行了测试。测试结果表明，设计较为满意的实现了电视采集卡驱动程序的各功能，能够通过用户层应用程序访问驱动程序中暴露出的属性控制；对Windows操作系统和其他硬件设备有比较好的兼容性，仅在VBI信号的处理和控制方面还需要进一步完善。目前，设计的驱动程序已被某些公司采用并到好评。更多还原

【Abstract】 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.更多还原