如何在opencv js中访问findContours()中的数据

<script async src="https://docs.opencv.org/master/opencv.js" onload="onOpenCvReady();" type="text/javascript"></script>

function onOpenCvReady() {
  cv.onRuntimeInitialized = function() {
    // OpenCV.js已加载完毕，可以开始使用
  };
}

const src = cv.imread('imageElement');

const gray = new cv.Mat();
cv.cvtColor(src, gray, cv.COLOR_RGBA2GRAY);
const binary = new cv.Mat();
cv.threshold(gray, binary, 127, 255, cv.THRESH_BINARY);

const contours = new cv.MatVector();
const hierarchy = new cv.Mat();
cv.findContours(binary, contours, hierarchy, cv.RETR_EXTERNAL, cv.CHAIN_APPROX_SIMPLE);

for (let i = 0; i < contours.size(); i++) {
  const contour = contours.get(i);
  // 访问轮廓数据，例如计算轮廓面积、周长等
}