# npm 
npm install express multer 
# or yarn 
yarn add express multer

// index.js 
const express = require('express'); 
const fs = require('fs'); 
const path = require('path'); 
const http = require('http'); 
const https = require('https'); 
 
//static 托管静态文件 用于客户端访问gif图片 
app.use('/public',express.static(path.join(__dirname,'public'))); 
 
//引入 ffmpegRouter.js  
const ffmpegRouter= require('./ffmpegRouter') 
app.use('/ffmpeg',ffmpegRouter); 
 
// Configuare https 
const options = { 
  key : fs.readFileSync('[key文件路径]'), 
  cert: fs.readFileSync("[pem文件路径]"), 
} 
http.createServer(app).listen(80); // http端口 
https.createServer(options, app).listen(443); // https 端口

// ffmpegRouter.js 
const express = require('express') 
const router = express.Router() 
const fs = require('fs') 
const child = require('child_process') 
const multer  = require('multer') 
 
const storage = multer.diskStorage({ 
  destination: function(req,file,cb){ 
    cb(null,'./uploads'); 
  }, 
  filename: function(req,file,cb){ 
    // 以时间格式来命名文件，28800000为8小时的毫秒数，为了去除时区的误差 
    const date = new Date(Date.now()+28800000).toJSON().substring(5, 16).replace(/(T|:)/g, '-'); 
    // 随机 0 ~ 1000 的整数，防止同一时间上传的文件被覆盖 
    const random = parseInt(Math.random() * 1000); 
    // 提取文件类型 
    const type = file.originalname.split('.').pop(); 
    const filename = `${date}-${random}.${type}` 
    cb(null,filename); 
  } 
}); 
const upload = multer({ storage }) 
 
router.post('/transform/gif', upload.single('file'), (req, res) => { 
  transform(req.file, req, res) 
}) 
 
function transform(file, req, res) { 
  let { path, filename } = file; 
  let {  
    start, //开始时间 
    end, //结束时间 
    sizeLimit, //大小限制 
    dpi, //分辨率 
    framePerSecond, //每秒帧率 
    pts, //倍速 
    toning, //调色 
    contrast, // 对比度 
    brightness, // 亮度 
    saturation, // 饱和度 
    effects, // 特效 
    crop, // 裁剪 
  } = req.body; 
  //类型检查 
  let type = filename.split('.').pop(); 
  let allowTypes = ['gif', 'mp4','avi', 'amv', 'dmv', 'mov', 'qt', 'flv', 'mpeg', 'mpg', 'm4v', 'm3u8', 'webm',  
    'mtv', 'dat', 'wmv', 'ram', '3gp', 'viv', 'rm', 'rmvb']; 
  if (!allowTypes.includes(type)) { 
    fs.unlink(path, () => { 
      console.log(`文件类型不支持：${filename} `); 
    }); 
    return res.send({ err: -2, msg: '文件类型不支持' }); 
  } 
 
  const Option = { 
    list: ['-ss', '-to', '-i', '-fs', '-vf', '-s', '-r', '-y'], 
    init() { 
      this.list.forEach(x => this[x] = '') 
    }, 
    add(name, value) { 
      this[name] += (this[name] ? ',' : '') + value; 
    }, 
    get(name) { 
      return this[name] ? `${name} ${this[name]} ` : '' 
    }, 
    toString() { 
      return this.list.reduce(((p,c) =>  p + this.get(c) ),'') 
    } 
  } 
  Option.init() 
 
  /** 
   *  ...配置Option 下文解释 
   */ 
 
  Option.add('-i', path); 
  let rfilen = `public/picture/gif/${filename}.gif` 
  Option.add('-y', rfilen); 
 
  let optionStr = Option.toString() 
 
  child.exec(`ffmpeg ${optionStr}`, function (err) { 
    fs.unlink(path, () => { 
      console.log('视频转GIF：' + filename); 
      console.log(optionStr); 
    }); 
 
    if (err) { 
      console.error(err) 
      res.send({ err: -1, msg: err }) 
    } else { 
      //定时删除 
const mins = 60 * 3; 
      const limitTime = mins * 60 * 1000 
      const expired = +new Date() + limitTime 
      const stat = fs.statSync(rfilen) 
      setTimeout(() => { 
        fs.unlink(rfilen, () => { 
          console.log(`GIF文件：${filename} 已删除！`) 
        }); 
      }, limitTime) 
      res.send({ 
        err: 0, 
        msg: `视频转gif处理成功,有效期${mins}分钟！`, 
        url: `https://[服务器地址]/${rfilen}`, 
        size: stat.size, 
        expiredIn: expired, 
      }); 
    } 
  }) 
} 
 
module.exports = router

const Option = { 
    list: ['-ss', '-to', '-i', '-fs', '-vf', '-s', '-r', '-y'], 
    init() { 
      this.list.forEach(x => this[x] = '') 
    }, 
    add(name, value) { 
      this[name] += (this[name] ? ',' : '') + value; 
    }, 
    get(name) { 
      return this[name] ? `${name} ${this[name]} ` : '' 
    }, 
    toString() { 
      return this.list.reduce(((p,c) =>  p + this.get(c)),'') 
    } 
}

//时间 
if (start && end){ 
    if (Number(start) > Number(end)) { 
        return res.send({ err: -4, msg: '时间参数错误' }) 
    } 
    Option.add('-ss',start) 
    Option.add('-to',end) 
} 
//大小限制 
if (sizeLimit && sizeLimit != '默认') { 
    Option.add('-fs', sizeLimit) 
} 
//分辨率 
if (dpi) { 
    if (dpi == '默认') { 
        dpi = '480p'; 
    } 
    if (dpi.endsWith('p')) { 
        Option.add('-vf', `scale=-2:${dpi.substr(0, dpi.length - 1)}`) 
    } else { 
        Option.add('-s',dpi) 
    } 
} 
//帧率 
if (framePerSecond && framePerSecond != '默认') { 
    Option.add('-r', framePerSecond); 
} 
//倍速 
if (pts && pts != '默认') { 
    pts = Number(pts) 
    pts = 1 / pts; 
    if (pts < 0.25) { 
        pts = 0.25  
    } else if (pts > 4) { 
        pts = 4 
    } 
    Option.add('-vf', `setpts=${pts}*PTS`) 
} 
//调色 
if (contrast !== undefined || brightness !== undefined || saturation !== undefined) { 
    const list = [] 
    if (contrast !== undefined) { 
        list.push(`contrast=${contrast}`) 
    } 
    if (brightness !== undefined) { 
        list.push(`brightness=${brightness}`) 
    } 
    if (saturation !== undefined) { 
        list.push(`saturation=${saturation}`) 
    } 
    Option.add("-vf", 'eq=' + list.join(':')); 
} 
if (crop) { 
    Option.add('-vf', `crop=${crop}`) 
} 
//特效 
if (effects && effects != '默认') { 
    switch(effects){ 
        case '边缘' : Option.add("-vf", "edgedetect=low=0.1:high=0.4");break; 
        case '油画' : Option.add("-vf", "edgedetect=mode=colormix:high=0");break; 
        case '上下切割' : Option.add("-vf", "stereo3d=abl:sbsr");break; 
        case '模糊' : Option.add('-vf','boxblur=2:1');break; 
        case '防抖' : Option.add('-vf','deshake=edge=1:search=0');break; 
        case '倒放' : Option.add('-vf','reverse');break; 
        default: break; 
    } 
}