29 lines
1.1 KiB
JavaScript
29 lines
1.1 KiB
JavaScript
/**
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* Extended Lame Header
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*/
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import * as Token from 'token-types';
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import * as common from '../common/Util.js';
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import { ReplayGain } from './ReplayGainDataFormat.js';
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/**
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* Info Tag
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* @link http://gabriel.mp3-tech.org/mp3infotag.html
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* @link https://github.com/quodlibet/mutagen/blob/abd58ee58772224334a18817c3fb31103572f70e/mutagen/mp3/_util.py#L112
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*/
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export const ExtendedLameHeader = {
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len: 27,
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get: (buf, off) => {
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const track_peak = Token.UINT32_BE.get(buf, off + 2);
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return {
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revision: common.getBitAllignedNumber(buf, off, 0, 4),
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vbr_method: common.getBitAllignedNumber(buf, off, 4, 4),
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lowpass_filter: 100 * Token.UINT8.get(buf, off + 1),
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track_peak: track_peak === 0 ? null : track_peak / 2 ** 23,
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track_gain: ReplayGain.get(buf, 6),
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album_gain: ReplayGain.get(buf, 8),
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music_length: Token.UINT32_BE.get(buf, off + 20),
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music_crc: Token.UINT8.get(buf, off + 24),
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header_crc: Token.UINT16_BE.get(buf, off + 24)
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};
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}
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};
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