securityos/node_modules/music-metadata/lib/flac/FlacParser.js

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.FlacParser = void 0;
const token_types_1 = require("token-types");
const debug_1 = require("debug");
const util = require("../common/Util");
const Vorbis_1 = require("../ogg/vorbis/Vorbis");
const AbstractID3Parser_1 = require("../id3v2/AbstractID3Parser");
const FourCC_1 = require("../common/FourCC");
const VorbisParser_1 = require("../ogg/vorbis/VorbisParser");
const VorbisDecoder_1 = require("../ogg/vorbis/VorbisDecoder");
const debug = (0, debug_1.default)('music-metadata:parser:FLAC');
/**
 * FLAC supports up to 128 kinds of metadata blocks; currently the following are defined:
 * ref: https://xiph.org/flac/format.html#metadata_block
 */
var BlockType;
(function (BlockType) {
    BlockType[BlockType["STREAMINFO"] = 0] = "STREAMINFO";
    BlockType[BlockType["PADDING"] = 1] = "PADDING";
    BlockType[BlockType["APPLICATION"] = 2] = "APPLICATION";
    BlockType[BlockType["SEEKTABLE"] = 3] = "SEEKTABLE";
    BlockType[BlockType["VORBIS_COMMENT"] = 4] = "VORBIS_COMMENT";
    BlockType[BlockType["CUESHEET"] = 5] = "CUESHEET";
    BlockType[BlockType["PICTURE"] = 6] = "PICTURE";
})(BlockType || (BlockType = {}));
class FlacParser extends AbstractID3Parser_1.AbstractID3Parser {
    constructor() {
        super(...arguments);
        this.padding = 0;
    }
    /**
     * Initialize parser with output (metadata), input (tokenizer) & parsing options (options).
     * @param {INativeMetadataCollector} metadata Output
     * @param {ITokenizer} tokenizer Input
     * @param {IOptions} options Parsing options
     */
    init(metadata, tokenizer, options) {
        super.init(metadata, tokenizer, options);
        this.vorbisParser = new VorbisParser_1.VorbisParser(metadata, options);
        return this;
    }
    async postId3v2Parse() {
        const fourCC = await this.tokenizer.readToken(FourCC_1.FourCcToken);
        if (fourCC.toString() !== 'fLaC') {
            throw new Error('Invalid FLAC preamble');
        }
        let blockHeader;
        do {
            // Read block header
            blockHeader = await this.tokenizer.readToken(Metadata.BlockHeader);
            // Parse block data
            await this.parseDataBlock(blockHeader);
        } while (!blockHeader.lastBlock);
        if (this.tokenizer.fileInfo.size && this.metadata.format.duration) {
            const dataSize = this.tokenizer.fileInfo.size - this.tokenizer.position;
            this.metadata.setFormat('bitrate', 8 * dataSize / this.metadata.format.duration);
        }
    }
    parseDataBlock(blockHeader) {
        debug(`blockHeader type=${blockHeader.type}, length=${blockHeader.length}`);
        switch (blockHeader.type) {
            case BlockType.STREAMINFO:
                return this.parseBlockStreamInfo(blockHeader.length);
            case BlockType.PADDING:
                this.padding += blockHeader.length;
                break;
            case BlockType.APPLICATION:
                break;
            case BlockType.SEEKTABLE:
                break;
            case BlockType.VORBIS_COMMENT:
                return this.parseComment(blockHeader.length);
            case BlockType.CUESHEET:
                break;
            case BlockType.PICTURE:
                return this.parsePicture(blockHeader.length).then();
            default:
                this.metadata.addWarning('Unknown block type: ' + blockHeader.type);
        }
        // Ignore data block
        return this.tokenizer.ignore(blockHeader.length).then();
    }
    /**
     * Parse STREAMINFO
     */
    async parseBlockStreamInfo(dataLen) {
        if (dataLen !== Metadata.BlockStreamInfo.len)
            throw new Error('Unexpected block-stream-info length');
        const streamInfo = await this.tokenizer.readToken(Metadata.BlockStreamInfo);
        this.metadata.setFormat('container', 'FLAC');
        this.metadata.setFormat('codec', 'FLAC');
        this.metadata.setFormat('lossless', true);
        this.metadata.setFormat('numberOfChannels', streamInfo.channels);
        this.metadata.setFormat('bitsPerSample', streamInfo.bitsPerSample);
        this.metadata.setFormat('sampleRate', streamInfo.sampleRate);
        if (streamInfo.totalSamples > 0) {
            this.metadata.setFormat('duration', streamInfo.totalSamples / streamInfo.sampleRate);
        }
    }
    /**
     * Parse VORBIS_COMMENT
     * Ref: https://www.xiph.org/vorbis/doc/Vorbis_I_spec.html#x1-640004.2.3
     */
    async parseComment(dataLen) {
        const data = await this.tokenizer.readToken(new token_types_1.Uint8ArrayType(dataLen));
        const decoder = new VorbisDecoder_1.VorbisDecoder(data, 0);
        decoder.readStringUtf8(); // vendor (skip)
        const commentListLength = decoder.readInt32();
        for (let i = 0; i < commentListLength; i++) {
            const tag = decoder.parseUserComment();
            this.vorbisParser.addTag(tag.key, tag.value);
        }
    }
    async parsePicture(dataLen) {
        if (this.options.skipCovers) {
            return this.tokenizer.ignore(dataLen);
        }
        else {
            const picture = await this.tokenizer.readToken(new Vorbis_1.VorbisPictureToken(dataLen));
            this.vorbisParser.addTag('METADATA_BLOCK_PICTURE', picture);
        }
    }
}
exports.FlacParser = FlacParser;
class Metadata {
}
Metadata.BlockHeader = {
    len: 4,
    get: (buf, off) => {
        return {
            lastBlock: util.getBit(buf, off, 7),
            type: util.getBitAllignedNumber(buf, off, 1, 7),
            length: token_types_1.UINT24_BE.get(buf, off + 1)
        };
    }
};
/**
 * METADATA_BLOCK_DATA
 * Ref: https://xiph.org/flac/format.html#metadata_block_streaminfo
 */
Metadata.BlockStreamInfo = {
    len: 34,
    get: (buf, off) => {
        return {
            // The minimum block size (in samples) used in the stream.
            minimumBlockSize: token_types_1.UINT16_BE.get(buf, off),
            // The maximum block size (in samples) used in the stream.
            // (Minimum blocksize == maximum blocksize) implies a fixed-blocksize stream.
            maximumBlockSize: token_types_1.UINT16_BE.get(buf, off + 2) / 1000,
            // The minimum frame size (in bytes) used in the stream.
            // May be 0 to imply the value is not known.
            minimumFrameSize: token_types_1.UINT24_BE.get(buf, off + 4),
            // The maximum frame size (in bytes) used in the stream.
            // May be 0 to imply the value is not known.
            maximumFrameSize: token_types_1.UINT24_BE.get(buf, off + 7),
            // Sample rate in Hz. Though 20 bits are available,
            // the maximum sample rate is limited by the structure of frame headers to 655350Hz.
            // Also, a value of 0 is invalid.
            sampleRate: token_types_1.UINT24_BE.get(buf, off + 10) >> 4,
            // probably slower: sampleRate: common.getBitAllignedNumber(buf, off + 10, 0, 20),
            // (number of channels)-1. FLAC supports from 1 to 8 channels
            channels: util.getBitAllignedNumber(buf, off + 12, 4, 3) + 1,
            // bits per sample)-1.
            // FLAC supports from 4 to 32 bits per sample. Currently the reference encoder and decoders only support up to 24 bits per sample.
            bitsPerSample: util.getBitAllignedNumber(buf, off + 12, 7, 5) + 1,
            // Total samples in stream.
            // 'Samples' means inter-channel sample, i.e. one second of 44.1Khz audio will have 44100 samples regardless of the number of channels.
            // A value of zero here means the number of total samples is unknown.
            totalSamples: util.getBitAllignedNumber(buf, off + 13, 4, 36),
            // the MD5 hash of the file (see notes for usage... it's a littly tricky)
            fileMD5: new token_types_1.Uint8ArrayType(16).get(buf, off + 18)
        };
    }
};