In
order to identify chronic, acute, brown dot and white dot, four types of rice
blast diseases early and accurately, a deep neural network is constructed by
combining sparse automatic encoder and SPSO-SVM (Switching Particle Swarm
Optimization Support Vector Machine). Compared with other algorithms, the
neural network needs to input a large number of images, the autoencoder can
extract the most representative information in the original image, reduce the
amount of information in the input, and then put the reduced information into
the neural network to learn, greatly reducing the difficulty and time of
learning. Firstly, the input data is encoded, decoded and reconstructed by
sparse automatic encoder to learn the hierarchical features of rice blast leaf
spots, and the sparse condition constraint is added to the automatic encoder to
compress the hidden layer, so as to learn the higher-level hidden features.
Secondly, the support vector machine optimized by switching particle swarm optimization is used to identify the types
of rice blast. The open Kaggle rice disease image database and the actually
collected rice blast image are used as the data set. 350 images of each type
were selected to form samples, and each image is normalized to 4096
dimensional vector. 80% of the samples are randomly selected as the training
set and the remaining 20% are used as the test set. Through 10 cross
validation, the average recognition accuracy of the test set is 95. 7% . The
experimental results show that the proposed method can effectively identify the
early disease of rice leaf blast from the features of disease spots, which is
of great significance for the early prevention of rice blast.