Abstract: 【Aim】 This study aims to design and develop a survey method based on mobile terminal for rice planthoppers in paddy fields, so as to reduce the labor intensity, improve the objectivity of rice planthopper survey in paddy fields and trace the survey results of rice planthoppers. 【Methods】 An image acquisition device for rice planthoppers in paddy fields was developed by an Android camera, a handheld extendable pole and an Android mobile phone loaded with camera APP. In the Android development environment, the video capture and encoding module, the video transport module and the camera controlling module of the Android camera were developed by the socket communication and video coding technologies. The video preview module, the mobile controlling module and the image uploading module on the mobile phone were developed by the Android NDK and Java web technologies. The video in the camera was compressed into H.264 format file in real time, which was transmitted to the mobile phone by the RTSP/RTP protocol. The phone can preview the video captured by the camera by decompression, control the camera to capture the rice planthopper images, and simultaneously transmit the images to the mobile phone. The automatic identification algorithm for rice planthoppers was deployed in the cloud server. The clients can select the rice planthopper images to upload to the cloud server. The identification results would be returned to the mobile phone after running the identification algorithm in the server. 【Results】 By using the survey method based on the mobile terminal for rice planthoppers in paddy fields, the mobile phone can preview the video of rice planthoppers at the base of rice stem captured by the camera in real time and control the camera to take pictures. The automatic identification algorithm for rice planthoppers in the cloud server can identify both the rice planthoppers in the image and their developmental stages, with the average detection rates of 86.9% and 81.7%, and the false alarm rates of 11.2% and 16.6%, respectively. 【Conclusion】 The survey method based on the mobile terminal for rice planthoppers can easily collect the images of rice planthoppers at the base of rice plants, and quickly identify and count the number of rice planthoppers in different developmental stages. This method can not only reduce the labor of forecasting technicians, but also avoid the survey subjectivity of rice planthoppers in paddy fields and realize the traceability of rice planthopper survey.

Key words: Rice planthopper, field survey, image identification, automatic counting, Android mobile phone, Android camera