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) }) }) } // --------------------------------------------------------------------------- // Audio // --------------------------------------------------------------------------- const imageCodecs = new Set([ 'ansi', 'apng', 'bintext', 'bmp', 'brender_pix', 'dpx', 'exr', 'fits', 'gem', 'gif', 'jpeg2000', 'jpgls', 'mjpeg', 'mjpegb', 'msp2', 'pam', 'pbm', 'pcx', 'pfm', 'pgm', 'pgmyuv', 'pgx', 'photocd', 'pictor', 'png', 'ppm', 'psd', 'sgi', 'sunrast', 'svg', 'targa', 'tiff', 'txd', 'webp', 'xbin', 'xbm', 'xface', 'xpm', 'xwd' ]) async function isAudioFile (path: string, existingProbe?: FfprobeData) { const videoStream = await getVideoStream(path, existingProbe) if (!videoStream) return true if (imageCodecs.has(videoStream.codec_name)) return true return false } async function hasAudioStream (path: string, existingProbe?: FfprobeData) { const { audioStream } = await getAudioStream(path, existingProbe) return !!audioStream } 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 } } // --------------------------------------------------------------------------- // Video // --------------------------------------------------------------------------- async function getVideoStreamDimensionsInfo (path: string, existingProbe?: FfprobeData) { const videoStream = await getVideoStream(path, existingProbe) if (!videoStream) return undefined return { width: videoStream.width, height: videoStream.height, ratio: Math.max(videoStream.height, videoStream.width) / Math.min(videoStream.height, videoStream.width), resolution: Math.min(videoStream.height, videoStream.width), isPortraitMode: videoStream.height > videoStream.width } } async function getVideoStreamFPS (path: string, existingProbe?: FfprobeData) { const videoStream = await getVideoStream(path, existingProbe) if (!videoStream) 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 buildFileMetadata (path: string, existingProbe?: FfprobeData) { const metadata = existingProbe || await ffprobePromise(path) return new VideoFileMetadata(metadata) } async function getVideoStreamBitrate (path: string, existingProbe?: FfprobeData): Promise<number> { const metadata = await buildFileMetadata(path, existingProbe) let bitrate = metadata.format.bit_rate as number if (bitrate && !isNaN(bitrate)) return bitrate const videoStream = await getVideoStream(path, existingProbe) if (!videoStream) return undefined bitrate = videoStream?.bit_rate if (bitrate && !isNaN(bitrate)) return bitrate return undefined } async function getVideoStreamDuration (path: string, existingProbe?: FfprobeData) { const metadata = await buildFileMetadata(path, existingProbe) return Math.round(metadata.format.duration) } async function getVideoStream (path: string, existingProbe?: FfprobeData) { const metadata = await buildFileMetadata(path, existingProbe) return metadata.streams.find(s => s.codec_type === 'video') } // --------------------------------------------------------------------------- export { getVideoStreamDimensionsInfo, buildFileMetadata, getMaxAudioBitrate, getVideoStream, getVideoStreamDuration, getAudioStream, getVideoStreamFPS, isAudioFile, ffprobePromise, getVideoStreamBitrate, hasAudioStream }