Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you may not be able to execute some actions.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
矩形、圆形和三角形三者有时候可以识别准确，有时候不行？怎么优化算法呢？
什么时候不行？
提供一下具体的代码，和测试的图片。