摘要
医用无线内窥镜系统具有重要的临床应用价值和商业价值,随着无创医疗技术的发展,无线内窥镜成为人体胃肠道微诊疗系统的重要分支之一。无线内窥镜克服了管道式内窥镜的局限,微型摄像胶囊通过吞咽进入肠道,可以对食道、胃、小肠和大肠进行特定和非特定位置的图像拍摄,从而可以对整个消化道系统进行检测,克服了传统电子内窥镜只能检测胃部及部分肠道的缺陷。
本论文主要研究基于嵌入式系统的无线内窥镜系统便携式装置的设计以及图像工作站的设计。从软件和硬件两方面详细介绍了便携式装置的设计开发过程及其中涉及到的相关技术。系统硬件控制平台的研究主要包括:S3C2410微处理器的体系结构,射频及低频模块设计,以及USB主从控制以及HH2410开发板的应用等;系统软件运行平台的研究主要包括:Linux操作系统的工作机制,Linux环境下USB驱动程序、射频驱动和低频驱动的设计。图像工作站主要划分为数据通信模块,图像处理模块,数据管理模块,系统功能模块;每个模块能独立完成相应的功能,便于医务人员观察和利用拍摄到的图像资料。
本系统将胶囊内窥镜输出的数字图像数据通过射频模块传送至本便携式装置,便携式装置再通过USB端口将这些图像传送到图像工作站。胶囊内窥镜的工作参数可直接通过便携式装置的低频模块来修改,也可在线工作时直接在图像工作站中修改。嵌入式操作系统选用Linux,并根据系统的特点设计了具体的软硬件方案。
便携式装置实现了基于HH2410开发板的图像数据采集及控制的功能,完成了消化道图像的获取以及保存、内窥镜胶囊的控制等功能;图像工作站则提供了一个的图像处理、图像存储、病案管理和图像诊断的平台。利用模拟内窥镜拍摄的含有噪声的彩色肠道图像:含有高斯和椒盐两者混合噪声的肠道图像来验证图像工作站系统功能。
A wireless endoscope system developed on the embedded Linux platform is presented in this paper. This wireless endoscope system which consists of endoscope capsule, portable equipment and image workstation, can meet the needs of wireless and portable functions. The endoscope capsule for gastrointestinal inspection should be gulped down by patients, and the portable equipment should be carried to receive the images of gastrointestinal (GI) tract via the radio frequency module. The parameters of the capsule can be set or read back by portable equipment with low frequency module. Acquired image data can be saved as FAT32 format file in USB disk, which can be processed and reviewed at windows PC workstation in the next stage.
Medical wireless endoscope system has important clinical value and commercial value.With the development of non-invasive medical technologies, wireless endoscope become an important branch of human gastrointestinal tract diagnosis and treatment micro-system. Wireless endoscope overcomes the limitations of pipeline endoscopes, it can be swallowed and than travel the whole digestive system– includes esophagus, stomach, small intestine and colon. The mini-camera in the endoscope capsule can take the pictures of specific or non-specific location. Thus the endoscope capsule can check-up the entire digestive system. It overcomes the defect of traditional electronic endoscope that it can only check-up the stomach and a part of the intestine.
This project had described the study of portable equipment and image workstation. The portable equipment is based on the embedded Linux and ARM core. This paper will introduce the hardware and software of portable equipment. The study of its hardware consists of S3C2410 microprocessor architecture, the low-frequency RF module design, USB host and device control and the application development board HH2410, and so on; its software contains working mechanisms of Linux operating system, USB device driver, radio frequency driver and low frequency driver design base the Linux environment. Image workstation mainly divided into four parts: data communication module, image processing module, data management module and system module. Each module can accomplish their functions independently, and then medical personnel will be able to observe and use of the image data captured.
The digital image data which acquired by endoscope capsule can sent to the portable equipment with their radio frequency module, and portable equipment also can transmit those image data to image workstation via the USB interface. Capsule endoscopy’s working parameters can be written by portable equipment directly, or amended by image workstations at online work status. We chose Linux operating system as our embedded system, and design the blue print of system hardware and software. Portable equipment had achieved functions of the image data acquisition and storage of digestive tract based on HH2410 development board. It can also control the endosecope capsule.
Image Workstation provides a platform for image processing, image storage, medical records management, image diagnostic. This paper simulates the RGB image that mixed Gaussian and Salt & Pepper noise as the image comes form endoscopy. The basical functions of image workstation had succeeded.
引文
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