server/helpers/ffmpeg-utils.ts

   1 import * as ffmpeg from 'fluent-ffmpeg'
   2 import { join } from 'path'
   3 import { VideoResolution } from '../../shared/models/videos'
   4 import { CONFIG, VIDEO_TRANSCODING_FPS } from '../initializers'
   5 import { unlinkPromise } from './core-utils'
   6 import { processImage } from './image-utils'
   7 import { logger } from './logger'
   8
   9 async function getVideoFileResolution (path: string) {
  10   const videoStream = await getVideoFileStream(path)
  11
  12   return {
  13     videoFileResolution: Math.min(videoStream.height, videoStream.width),
  14     isPortraitMode: videoStream.height > videoStream.width
  15   }
  16 }
  17
  18 async function getVideoFileFPS (path: string) {
  19   const videoStream = await getVideoFileStream(path)
  20
  21   for (const key of [ 'r_frame_rate' , 'avg_frame_rate' ]) {
  22     const valuesText: string = videoStream[key]
  23     if (!valuesText) continue
  24
  25     const [ frames, seconds ] = valuesText.split('/')
  26     if (!frames || !seconds) continue
  27
  28     const result = parseInt(frames, 10) / parseInt(seconds, 10)
  29     if (result > 0) return result
  30   }
  31
  32   return 0
  33 }
  34
  35 function getDurationFromVideoFile (path: string) {
  36   return new Promise<number>((res, rej) => {
  37     ffmpeg.ffprobe(path, (err, metadata) => {
  38       if (err) return rej(err)
  39
  40       return res(Math.floor(metadata.format.duration))
  41     })
  42   })
  43 }
  44
  45 async function generateImageFromVideoFile (fromPath: string, folder: string, imageName: string, size: { width: number, height: number }) {
  46   const pendingImageName = 'pending-' + imageName
  47
  48   const options = {
  49     filename: pendingImageName,
  50     count: 1,
  51     folder
  52   }
  53
  54   const pendingImagePath = join(folder, pendingImageName)
  55
  56   try {
  57     await new Promise<string>((res, rej) => {
  58       ffmpeg(fromPath)
  59         .on('error', rej)
  60         .on('end', () => res(imageName))
  61         .thumbnail(options)
  62     })
  63
  64     const destination = join(folder, imageName)
  65     await processImage({ path: pendingImagePath }, destination, size)
  66   } catch (err) {
  67     logger.error('Cannot generate image from video %s.', fromPath, err)
  68
  69     try {
  70       await unlinkPromise(pendingImagePath)
  71     } catch (err) {
  72       logger.debug('Cannot remove pending image path after generation error.', err)
  73     }
  74   }
  75 }
  76
  77 type TranscodeOptions = {
  78   inputPath: string
  79   outputPath: string
  80   resolution?: VideoResolution
  81   isPortraitMode?: boolean
  82 }
  83
  84 function transcode (options: TranscodeOptions) {
  85   return new Promise<void>(async (res, rej) => {
  86     const fps = await getVideoFileFPS(options.inputPath)
  87
  88     let command = ffmpeg(options.inputPath)
  89                     .output(options.outputPath)
  90                     .videoCodec('libx264')
  91                     .outputOption('-threads ' + CONFIG.TRANSCODING.THREADS)
  92                     .outputOption('-movflags faststart')
  93                     // .outputOption('-crf 18')
  94
  95     // Our player has some FPS limits
  96     if (fps > VIDEO_TRANSCODING_FPS.MAX) command = command.withFPS(VIDEO_TRANSCODING_FPS.MAX)
  97     else if (fps < VIDEO_TRANSCODING_FPS.MIN) command = command.withFPS(VIDEO_TRANSCODING_FPS.MIN)
  98
  99     if (options.resolution !== undefined) {
 100       // '?x720' or '720x?' for example
 101       const size = options.isPortraitMode === true ? `${options.resolution}x?` : `?x${options.resolution}`
 102       command = command.size(size)
 103     }
 104
 105     command.on('error', rej)
 106            .on('end', res)
 107            .run()
 108   })
 109 }
 110
 111 // ---------------------------------------------------------------------------
 112
 113 export {
 114   getVideoFileResolution,
 115   getDurationFromVideoFile,
 116   generateImageFromVideoFile,
 117   transcode,
 118   getVideoFileFPS
 119 }
 120
 121 // ---------------------------------------------------------------------------
 122
 123 function getVideoFileStream (path: string) {
 124   return new Promise<any>((res, rej) => {
 125     ffmpeg.ffprobe(path, (err, metadata) => {
 126       if (err) return rej(err)
 127
 128       const videoStream = metadata.streams.find(s => s.codec_type === 'video')
 129       if (!videoStream) throw new Error('Cannot find video stream of ' + path)
 130
 131       return res(videoStream)
 132     })
 133   })
 134 }