CMOS image channel in the application of ultrasonic equipment (1)

Summary: this article describes a CMOS image channel for image transmission of portable ultrasonic equipment control system.

System based on the ARM 32-bit microprocessors and embedded Linux operating system, completed the diagnostic images in CMOS image channels of transmission and processing for diagnostic images real-time display and large capacity non-volatile storage. Build a diagnostic instrument not only powerful, extended easily, but also take into account the requirements miniaturization.

1 Introduction

As medical diagnostic apparatus miniaturization, the process of portable, high-performance 32-bit microprocessors are increasingly applied to all kinds of small medical imaging equipment, but how to leverage these microprocessors and real-time image processing, it is a question of the assistants to be resolved.

Starting from ARM 7 series, ARM processors that integrates CMOS (Complementary Metal Oxide SemiConductor) image sensor interface, to address this problem provides possible. Processor can use CMOS image sensor interface adapts to different CMOS image sensor. By CMOS interface, image data will be fed into the system CMOS image channels. CMOS image channel for CMOS image sensor interface and system AHB (Advanced High peRFormanceBus) bus connection pathway, CSI (CMOS Sensor Interface) and PRP (Pre-Processor). The channel is designed for high speed image transmission, offers a variety of image formats for input and transmission and channel within a color space conversion, forms, adjustment, and other operations that are diagnostic images, as well as other image transmission ideal channel.

This article discusses an approach based on 32-bit microprocessor ARM9E and embedded Linux portable ultrasonic equipment solutions.

System CMOS image channel for the transport of diagnostic network like channel acquisition of ultrasonic image information sent one system bus, the embedded operating system platforms, Ijnux enables real-time display of diagnostic images and static images of large capacity non-volatile storage, the realization of the diagnostic system not only powerful, extended easily, but also take into account the requirements miniaturization.

2 system architecture

This design of portable ultrasonic equipment system structure as shown in Figure l.

User input device to enter the control command system, the complete collection of ultrasound images, display, save, etc. When performing a scan command system through the serial port to the FPGA to the core of the ultrasound image acquisition module to send image acquisition command, control of ultrasonic probes scan driver circuit and signal transmitter receiver synchronization actions. Receiving of ultrasonic signal in ultrasound image capture module has been enlarged, ADC evacuations of people complete FPGA, digital scan converter (DCS) and interpolation, been two-dimensional ultrasound image information. The image information to format the converted through ARM chip CMOS received 13 control system sending the image channel transport, completed in LCD (Liquid Crystal Display) on the real-time display, and a detachable large-capacity SD (Secure Digital Memory Card) card available on the desired image to save it. Save the image information can be performed off-line processing, such as printing, film playback, remote viewing, etc.

3 system hardware design

3.1 hardware diagram

This design choice to ARM926EJ-S for Freescale i.MX21 kernel as the processor, the control system hardware box ya as shown in Figure 2, the system is based on the ARM processor core, plus compatible hardware peripherals.

Ultrasonic acquisition modules complete the image acquisition and transmission from the incoming, LCD image information real-time display, SD card to a large number of image data saved for later processing. Pass Plus USB HUB. The mouse, keyboard, printer access system. Local storage of image data can be controlled via a fast Ethernet network processor, fed through DM9000 Ethernet remote browsing.

3.2 CMOS image channel

This control system CMOS image channel block diagram shown in Figure 3, the ultrasound image data of incoming use i.MX21 chip CMOS image sensor interface.

This interface supports image data types are RGB565, RGB888, YUV422, YUV444, etc. Different types of image data in CMOS mouth after CSI 8-bit sampling, packaged as a 32-bit image data sent people CSI RxFIFO. CSI RxFIFO in image data according to the type of the display, and storage hardware and software implementation is different.