RTCVideoSourceStats: frames 属性

// where sender is an RTCRtpSender
const stats = await sender.getStats();
let videoSourceStats = null;

stats.forEach((report) => {
  if (report.type === "media-source" && report.kind==="video") {
    videoSourceStats = report;
    break;
  }
});

const frames = videoSourceStats?.frames;