opencv加载knn模型失败的解决方案

1、拿到了一个knn模型，直接上手python opencv加载模型来使用

import cv2

# 加载 KNN 模型
knn_model = cv2.ml.KNearest_create()
knn_model.load('./caffewu/model/Digit_KNNModel.xml')  


print("Model loaded successfully: knn_model.isTrained() is ", knn_model.isTrained())

老是提示模型加载失败，郁闷！

Model loaded successfully: knn_model.isTrained() is  False

2、继续折腾，改用文件读取的方式

import cv2
import numpy as np

# 加载 KNN 模型
knn_model = cv2.ml.KNearest_create()
#knn_model.load('./caffewu/model/Digit_KNNModel.xml')  # load the model 记载模型失败

# 用这样加载模型才能成功
file = cv2.FileStorage('./caffewu/model/Digit_KNNModel.xml', cv2.FILE_STORAGE_READ)
knn_model.read(fn=file.getNode('opencv_ml_knn')) # knn.xml的模型节点名字 可以自行查看xml模型文件 获得

print("Model loaded successfully: knn_model.isTrained() is ", knn_model.isTrained())

终于运行成功了

Model loaded successfully: knn_model.isTrained() is  True