在 NodeJS 中从 Content-Length 中查找视频时长

Question

Is there any way to calculate the video duration in a millisecond from content-length?

request
  .get("http://myvideourl.com/filename.mp4")
  .on("response", response => {
    const content_length = response.headers.content-length;// "content-length": "1986943971"
    res.json({
      stream_duration: "",
      thumb: thumb,
      size: content_length,
    });
  });

Note : Video Format is MP4 , res is express object, request is a httpclient library in NodeJS

Answer 1

You can use this npm module It will help you to get the video length even from an url

const { getVideoDurationInSeconds } = require('get-video-duration');
getVideoDurationInSeconds('http://myvideourl.com/filename.mp4').then((duration) => {
    console.log(duration)
}) 

Of course you can then convert it into milliseconds. (x1000).

Answer 2

You can use one of these three npm modules.

https://www.npmjs.com/package/get-video-duration https://www.npmjs.com/package/node-video-duration (deprecated ?) https://www.npmjs.com/package/ffprobe (deprecated)

The first one seems up to date. There is an example from the doc

const { getVideoDurationInSeconds } = require('get-video-duration')

// From a local path...
getVideoDurationInSeconds('video.mov').then((duration) => {
  console.log(duration)
})

// From a URL...
getVideoDurationInSeconds('http://clips.vorwaerts-gmbh.de/big_buck_bunny.mp4').then((duration) => {
  console.log(duration)
})

// From a readable stream...

const fs = require('fs')
const stream = fs.createReadStream('video.mov')

getVideoDurationInSeconds(stream).then((duration) => {
  console.log(duration)
})

Answer 3

Not sure regarding 'Content-Length', But this gist will give you the video duration (and other useful data) in Node with fs:

const fs = require("fs").promises;
const buff = Buffer.alloc(100);
const header = Buffer.from("mvhd");

async function main() {
 const file = await fs.open("video.mp4", "r");
 const { buffer } = await file.read(buff, 0, 100, 0);

 await file.close();

 const start = buffer.indexOf(header) + 17;
 const timeScale = buffer.readUInt32BE(start);
 const duration = buffer.readUInt32BE(start + 4);

 const audioLength = Math.floor((duration / timeScale) * 1000) / 1000;

 console.log(buffer, header, start, timeScale, duration, audioLength);
}

main();