vue 获取视频第一帧

findvideocover() {
        let size = 160
        // 获取video节点
        const video = document.getElementById("videoPlay");
        video.width = size
        video.height = size
        video.currentTime = 1 // 第一帧
        //创建canvas对象
        const canvas = document.createElement("canvas")
        canvas.width = size
        canvas.height = size
        this.$nextTick(()=>{
          // 利用canvas对象方法绘图
          canvas.getContext("2d").drawImage(video, 0, 0, canvas.width, canvas.height);
          // 转换成base64形式
          const img = canvas.toDataURL("image/jpeg") // 这个就是图片的base64
          this.coverUrl = img
        })
      }