javascript - Tensorflow.js tf.browser.fromPixels() 必须是 HTMLVideoElement

Question

我在 node + nwjs 项目中使用 tensorflow.js，当我将视频元素作为输入到 tensowflow fromPixels 方法时，我在控制台中得到这个奇怪的错误作为输出:

Uncaught (in promise) Error: pixels passed to tf.browser.fromPixels()must be either an HTMLVideoElement, HTMLImageElement,HTMLCanvasElement, ImageData in browser, or OffscreenCanvas, ImageDatain webworker or {data: Uint32Array, width: number, height: number},but was HTMLVideoElement

所以我不明白出了什么问题......
生成错误的这行代码是:

const input_tensor = tf.browser.fromPixels(video);

video定义为:

export const video = document.getElementById("webcam");

那是指这个 HTML 元素:

<video id="webcam" autoplay muted></video>

Answer 1

视频元素尚未加载以显示视频。以下应该执行 fromPixel只有在视频开始加载后

const videoElement = document.getElementById("webcam");

videoElement.addEventListener('loadeddata', (e) => {
   //Video should now be loaded but we can add a second check

   if(videoElement.readyState >= 3){
       const input_tensor = tf.browser.fromPixels(video);
   }

});