如何使用 nodeJs 在 AWS lambda 中获取 MediaInfo

Question

我目前正在使用 nodeJs 中的 aws lambda 处理视频点播流程。我想使用基于存储在 S3 存储桶中的视频文件的设置来创建点播视频。要制作这样的东西，我需要使用 MediaInfo 提取信息（如帧率、分辨率、音频比特率...）。

我找到了这个 link https://aws.amazon.com/blogs/media/running-mediainfo-as-an-aws-lambda-function/ 但它是用 python 完成的。有没有人知道如何使用 lambda 而不是 python 的 nodeJs 环境来做这样的事情？

Answer 1

您可以使用 FFmpeg 和 FFprobe 获取此信息。在 AWS Lambda 中，您将 FFmpeg Lambda 层 ffmpeg-lambda-layer 用于 FFmpeg.

这是 index.js

的代码

process.env.PATH = process.env.PATH + ':' + process.env['LAMBDA_TASK_ROOT']

const AWS = require('aws-sdk')
const { spawn, spawnSync } = require('child_process')
const { createReadStream, createWriteStream } = require('fs')
const s3 = new AWS.S3()
const ffprobePath = '/opt/bin/ffprobe'
const ffmpegPath = '/opt/bin/ffmpeg'
const allowedTypes = ['mov', 'mpg', 'mpeg', 'mp4', 'wmv', 'avi', 'webm']
const width = 300
const height = 300
module.exports.handler = async (event, context) => {
    const srcKey = decodeURIComponent(event.Records[0].s3.object.key).replace(/\+/g, ' ')
    const bucket = event.Records[0].s3.bucket.name
    const target = s3.getSignedUrl('getObject', { Bucket: bucket, Key: srcKey, Expires: 1000 })
    let fileType = srcKey.match(/\.\w+$/)
    if (!fileType) {
        throw new Error(`invalid file type found for key: ${srcKey}`)
    }
    fileType = fileType[0].slice(1)
    if (allowedTypes.indexOf(fileType) === -1) {
        throw new Error(`filetype: ${fileType} is not an allowed type`)
    }  
 
    function getImageMediainfo() {
        return new Promise((resolve, reject) => {
        var output = [];
        var ffprobe = spawn(ffprobePath, [
            '-v', 'error',
            '-select_streams', 'v',
            '-show_entries', 
            'stream', //stream=width,height:stream_tags=rotate
            '-of','json',
            target
        ]);
        ffprobe.stdout.on('data', function(data) {
            output.push(data);
        });
        ffprobe.on('error', function(err) {
            console.log('ffprobe error: ', err);
            reject()
        });
        ffprobe.on('close', function() {
            var outputStr = output.join('');
            var jsonOut = {};
            jsonOut = JSON.parse(outputStr);
            console.log('outputStr', outputStr)
            console.log('outputStr', jsonOut)
            let framerates = jsonOut.streams[0].r_frame_rate // jsonOut.streams[0].avg_frame_rate
            let resolution = {
                width: jsonOut.streams[0].width,
                height: jsonOut.streams[0].height
            }
            let audio_bit_rate = jsonOut.streams[0].bit_rate
            console.log('framerates', framerates)
            console.log('resolution', resolution)
            console.log('audio_bit_rate', audio_bit_rate)
            resolve()
        })
    })      
  }
  await getImageMediainfo();
  return console.log(`processed ${bucket}/${srcKey} successfully`)
}

像这样输出

{
    "programs": [

    ],
    "streams": [
        {
            "index": 1,
            "codec_name": "h264",
            "codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
            "profile": "High",
            "codec_type": "video",
            "codec_time_base": "299/36000",
            "codec_tag_string": "avc1",
            "codec_tag": "0x31637661",
            "width": 720,
            "height": 1280,
            "coded_width": 720,
            "coded_height": 1280,
            "has_b_frames": 1,
            "pix_fmt": "yuvj420p",
            "level": 32,
            "color_range": "pc",
            "color_space": "bt709",
            "color_transfer": "bt709",
            "color_primaries": "bt709",
            "chroma_location": "left",
            "refs": 1,
            "is_avc": "true",
            "nal_length_size": "4",
            "r_frame_rate": "60/1",
            "avg_frame_rate": "18000/299",
            "time_base": "1/600",
            "start_pts": 0,
            "start_time": "0.000000",
            "duration_ts": 2093,
            "duration": "3.488333",
            "bit_rate": "3284683",
            "bits_per_raw_sample": "8",
            "nb_frames": "210",
            "disposition": {
                "default": 1,
                "dub": 0,
                "original": 0,
                "comment": 0,
                "lyrics": 0,
                "karaoke": 0,
                "forced": 0,
                "hearing_impaired": 0,
                "visual_impaired": 0,
                "clean_effects": 0,
                "attached_pic": 0,
                "timed_thumbnails": 0
            },
            "tags": {
                "rotate": "270",
                "creation_time": "2021-07-15T23:03:31.000000Z",
                "language": "und",
                "handler_name": "Core Media Video",
                "encoder": "H.264"
            },
            "side_data_list": [
                {
                    "side_data_type": "Display Matrix",
                    "displaymatrix": "\n00000000:            0      -65536           0\n00000001:        65536           0           0\n00000002:            0    83886080  1073741824\n",
                    "rotation": 90
                }
            ]
        }
    ]
}

如何使用 nodeJs 在 AWS lambda 中获取 MediaInfo

How to get MediaInfo in AWS lambda using nodeJs

amazon-s3

amazon-web-services

node.js

mediainfo

aws-lambda