PeerTube/shared/extra-utils/ffprobe.ts

188 lines
5.4 KiB
TypeScript

import { ffprobe, FfprobeData } from 'fluent-ffmpeg'
import { VideoFileMetadata } from '@shared/models/videos'
/**
*
* Helpers to run ffprobe and extract data from the JSON output
*
*/
function ffprobePromise (path: string) {
return new Promise<FfprobeData>((res, rej) => {
ffprobe(path, (err, data) => {
if (err) return rej(err)
return res(data)
})
})
}
async function isAudioFile (path: string, existingProbe?: FfprobeData) {
const videoStream = await getVideoStreamFromFile(path, existingProbe)
return !videoStream
}
async function getAudioStream (videoPath: string, existingProbe?: FfprobeData) {
// without position, ffprobe considers the last input only
// we make it consider the first input only
// if you pass a file path to pos, then ffprobe acts on that file directly
const data = existingProbe || await ffprobePromise(videoPath)
if (Array.isArray(data.streams)) {
const audioStream = data.streams.find(stream => stream['codec_type'] === 'audio')
if (audioStream) {
return {
absolutePath: data.format.filename,
audioStream,
bitrate: parseInt(audioStream['bit_rate'] + '', 10)
}
}
}
return { absolutePath: data.format.filename }
}
function getMaxAudioBitrate (type: 'aac' | 'mp3' | string, bitrate: number) {
const maxKBitrate = 384
const kToBits = (kbits: number) => kbits * 1000
// If we did not manage to get the bitrate, use an average value
if (!bitrate) return 256
if (type === 'aac') {
switch (true) {
case bitrate > kToBits(maxKBitrate):
return maxKBitrate
default:
return -1 // we interpret it as a signal to copy the audio stream as is
}
}
/*
a 192kbit/sec mp3 doesn't hold as much information as a 192kbit/sec aac.
That's why, when using aac, we can go to lower kbit/sec. The equivalences
made here are not made to be accurate, especially with good mp3 encoders.
*/
switch (true) {
case bitrate <= kToBits(192):
return 128
case bitrate <= kToBits(384):
return 256
default:
return maxKBitrate
}
}
async function getVideoStreamSize (path: string, existingProbe?: FfprobeData): Promise<{ width: number, height: number }> {
const videoStream = await getVideoStreamFromFile(path, existingProbe)
return videoStream === null
? { width: 0, height: 0 }
: { width: videoStream.width, height: videoStream.height }
}
async function getVideoFileResolution (path: string, existingProbe?: FfprobeData) {
const size = await getVideoStreamSize(path, existingProbe)
return {
width: size.width,
height: size.height,
ratio: Math.max(size.height, size.width) / Math.min(size.height, size.width),
resolution: Math.min(size.height, size.width),
isPortraitMode: size.height > size.width
}
}
async function getVideoFileFPS (path: string, existingProbe?: FfprobeData) {
const videoStream = await getVideoStreamFromFile(path, existingProbe)
if (videoStream === null) return 0
for (const key of [ 'avg_frame_rate', 'r_frame_rate' ]) {
const valuesText: string = videoStream[key]
if (!valuesText) continue
const [ frames, seconds ] = valuesText.split('/')
if (!frames || !seconds) continue
const result = parseInt(frames, 10) / parseInt(seconds, 10)
if (result > 0) return Math.round(result)
}
return 0
}
async function getMetadataFromFile (path: string, existingProbe?: FfprobeData) {
const metadata = existingProbe || await ffprobePromise(path)
return new VideoFileMetadata(metadata)
}
async function getVideoFileBitrate (path: string, existingProbe?: FfprobeData): Promise<number> {
const metadata = await getMetadataFromFile(path, existingProbe)
let bitrate = metadata.format.bit_rate as number
if (bitrate && !isNaN(bitrate)) return bitrate
const videoStream = await getVideoStreamFromFile(path, existingProbe)
if (!videoStream) return undefined
bitrate = videoStream?.bit_rate
if (bitrate && !isNaN(bitrate)) return bitrate
return undefined
}
async function getDurationFromVideoFile (path: string, existingProbe?: FfprobeData) {
const metadata = await getMetadataFromFile(path, existingProbe)
return Math.round(metadata.format.duration)
}
async function getVideoStreamFromFile (path: string, existingProbe?: FfprobeData) {
const metadata = await getMetadataFromFile(path, existingProbe)
return metadata.streams.find(s => s.codec_type === 'video') || null
}
async function canDoQuickAudioTranscode (path: string, probe?: FfprobeData): Promise<boolean> {
const parsedAudio = await getAudioStream(path, probe)
if (!parsedAudio.audioStream) return true
if (parsedAudio.audioStream['codec_name'] !== 'aac') return false
const audioBitrate = parsedAudio.bitrate
if (!audioBitrate) return false
const maxAudioBitrate = getMaxAudioBitrate('aac', audioBitrate)
if (maxAudioBitrate !== -1 && audioBitrate > maxAudioBitrate) return false
const channelLayout = parsedAudio.audioStream['channel_layout']
// Causes playback issues with Chrome
if (!channelLayout || channelLayout === 'unknown') return false
return true
}
// ---------------------------------------------------------------------------
export {
getVideoStreamSize,
getVideoFileResolution,
getMetadataFromFile,
getMaxAudioBitrate,
getVideoStreamFromFile,
getDurationFromVideoFile,
getAudioStream,
getVideoFileFPS,
isAudioFile,
ffprobePromise,
getVideoFileBitrate,
canDoQuickAudioTranscode
}