Question

我正在使用此代码来获取刚刚上传的图像＆＃34;使用fileReady(e) { let file: File = e[0]; let image = new Image(); let src: string; image.onload = function () { src = image.src; //do something with image }.bind(this); src = URL.createObjectURL(file); image.src = src; }进入浏览器并将数据发送到使用它的某个组件。

Video()

这适用于图像。下一个目标是让它也适用于视频。很遗憾，没有HTMLVideoElement构造函数，def cross_entropy(predictions, targets, epsilon=1e-12): """ Computes cross entropy between targets (encoded as one-hot vectors) and predictions. Input: predictions (N, k) ndarray targets (N, k) ndarray Returns: scalar """ predictions = np.clip(predictions, epsilon, 1. - epsilon) N = predictions.shape[0] ce = -np.sum(targets*np.log(predictions+1e-9))/N return ce predictions = np.array([[0.25,0.25,0.25,0.25], [0.01,0.01,0.01,0.96]]) targets = np.array([[0,0,0,1], [0,0,0,1]]) ans = 0.71355817782 #Correct answer x = cross_entropy(predictions, targets) print(np.isclose(x,ans))也没有做到这一点。我应该如何重写此代码以便它可以处理视频？

Answer 1

像这样：

fileReady(e) {
      const file: File = e[0];
      const fileReader = new FileReader();
      fileReader.onloadend = (event: any) => {
        const arrayBuffer = event.target.result;
        const fileType = "video/mpeg";
        const blob = new Blob(arrayBuffer , {type: fileType });
        const src = URL.createObjectURL(blob);
        video.src = src;
      };
      fileReader.readAsArrayBuffer(file);
    }

Answer 2

只需在答案中添加最新更新，

const blob = new Blob(arrayBuffer , {type: fileType });

将给出Blob需要可迭代的错误。因此解决方法是：

const blob = new Blob([arrayBuffer], {type: fileType });

从输入获取视频文件并在Typescript中显示它

2 个答案: