Research On High Speed Camera Acquisition And Image Processing System Of EAST

In order to realize plasma boundary reconstruction and plasma shape control based on the visible light camera,a high-speed,real-time camera acquisition and image pro-cessing system was developed on EAST device.The new acquisition system was op-timized in many ways to achieve high-speed,real-time,low-latency performance.The system was designed can load multiple acquisition cards on one machine to make it more flexible.In terms of acquisition,the new system uses KAYA’s acquisition card,of which the acquisition rate can be close to 10,000 FPS where the frame size set as 8-bit@320*240.And the system uses DMA and optimized memory copy function in data transmission,to reduce the time spent on data memory reading and writing.For the purpose of achieving real-time acquisition and real-time processing,the system is optimized in the following aspects.Firstly,configure the operating system kernel to avoid blocking the running of the acquisition process by the operating system kernel scheduling.Secondly,the acqui-sition and processing are divided into different threads,and they share same buffer data area to reduce the delay while the thread is allocated.The method of running acquisition and processing function on different CPU cores could prevent threads from falling into sleep.Thirdly,the data storage function is started after the end of the EAST device dis-charge to reducing data access waiting.In addition to performance,the acquisition and processing system also provides a number of features,such as command line parameter analysis,logging,etc.The visual display system based on Python web was developed to communicate with the acquisition machines and receive the image data from these acquisition machines.When received,the image data grabbed from different cameras will be combined as panorama image and displayed on the web page.In addition,the CNN model of EAST plasma discharge HotSpot and MARFE detection was developed.This mode can detect whether there are HotSpot and MARFE phenomena in the acquisition image during EAST discharge.On the data storage,the system optimizes the data storage format and provides a GUI for offline data analysis and processing based on Matlab.