"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.OpusParser = void 0; const Token = require("token-types"); const VorbisParser_1 = require("../vorbis/VorbisParser"); const Opus = require("./Opus"); /** * Opus parser * Internet Engineering Task Force (IETF) - RFC 6716 * Used by OggParser */ class OpusParser extends VorbisParser_1.VorbisParser { constructor(metadata, options, tokenizer) { super(metadata, options); this.tokenizer = tokenizer; this.lastPos = -1; } /** * Parse first Opus Ogg page * @param {IPageHeader} header * @param {Buffer} pageData */ parseFirstPage(header, pageData) { this.metadata.setFormat('codec', 'Opus'); // Parse Opus ID Header this.idHeader = new Opus.IdHeader(pageData.length).get(pageData, 0); if (this.idHeader.magicSignature !== "OpusHead") throw new Error("Illegal ogg/Opus magic-signature"); this.metadata.setFormat('sampleRate', this.idHeader.inputSampleRate); this.metadata.setFormat('numberOfChannels', this.idHeader.channelCount); } parseFullPage(pageData) { const magicSignature = new Token.StringType(8, 'ascii').get(pageData, 0); switch (magicSignature) { case 'OpusTags': this.parseUserCommentList(pageData, 8); this.lastPos = this.tokenizer.position - pageData.length; break; default: break; } } calculateDuration(header) { if (this.metadata.format.sampleRate && header.absoluteGranulePosition >= 0) { // Calculate duration const pos_48bit = header.absoluteGranulePosition - this.idHeader.preSkip; this.metadata.setFormat('numberOfSamples', pos_48bit); this.metadata.setFormat('duration', pos_48bit / 48000); if (this.lastPos !== -1 && this.tokenizer.fileInfo.size && this.metadata.format.duration) { const dataSize = this.tokenizer.fileInfo.size - this.lastPos; this.metadata.setFormat('bitrate', 8 * dataSize / this.metadata.format.duration); } } } } exports.OpusParser = OpusParser;