JS FLACMetadataEditor

Allows you to edit metadata of FLAC files. CO

Versión del día 12/04/2018. Echa un vistazo a la versión más reciente.

Este script no debería instalarse directamente. Es una biblioteca que utilizan otros scripts mediante la meta-directiva de inclusión // @require https://update.greasyfork.org/scripts/40545/264746/JS%20FLACMetadataEditor.js

Tendrás que instalar una extensión para tu navegador como Tampermonkey, Greasemonkey o Violentmonkey si quieres utilizar este script.

Necesitarás instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Userscripts para instalar este script.

Necesitará instalar una extensión como Tampermonkey para instalar este script.

Necesitarás instalar una extensión para administrar scripts de usuario si quieres instalar este script.

(Ya tengo un administrador de scripts de usuario, déjame instalarlo)

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

(Ya tengo un administrador de estilos de usuario, déjame instalarlo)

// ==UserScript==
// @description Allows you to edit metadata of FLAC files. CO
// @name        JS FLACMetadataEditor
// @namespace   universe.earth.www.ahohnmyc
// @version     0.0.1
// @license     GPL-3.0-or-later
// @grant       none
// ==/UserScript==

class VorbisComment extends Array {}

class VorbisCommentPacket {
    /* Need to easy initialization */
    _addComment(field) {
        let value = field.split('=')[1];
        field = field.split('=')[0].toUpperCase();
        if (!this.hasOwnProperty(field))
            this[field] = new VorbisComment();
        if (!this[field].some(storedValue=> storedValue===value))
            this[field].push(value.toString());
        return this;
    }
    toStringArray() {
        let array = [];
        Object.keys(this).sort().forEach(key=> {
            this[key].forEach(value=> {
                array.push(key+'='+value);
            });
        });
        return array;
    }
}

class FLACMetadataBlockData {}

class FLACMetadataBlock {
    constructor() {
        this.blockType = '';
        this.blockTypeNubmer = 0;
        this.blockSize = 0;
        this.data = new FLACMetadataBlockData();
        this.offset = 0;
    }
    get serializedSize() {
        switch (this.blockType) {
            case 'STREAMINFO': return 34;
            case 'PADDING': return this.blockSize;
            case 'APPLICATION': return 4+this.data.applicationData.length;
            case 'SEEKTABLE': return this.data.points.length*18;
            case 'VORBIS_COMMENT':
                let totl = this.data.comments.toStringArray().reduce((sum, str)=>sum+4+str.toUTF8().length, 0);
                return 4+this.data.vendorString.length+4+ totl;
            case 'CUESHEET': return 0;
            case 'PICTURE': return 4+4+this.data.MIMEType.toUTF8().length+4+this.data.description.toUTF8().length+4+4+4+4+4+this.data.data.length;
        }
    }
}

class FLACMetadataBlocks extends Array {}

class FLACMetadata {
    constructor() {
        this.blocks = new FLACMetadataBlocks();
        this.framesOffset = 0;
        this.signature = '';
    }
}

class FLACMetadataEditor {
    constructor(buffer) {
        if (!buffer || typeof buffer !== 'object' || !('byteLength' in buffer)) {
            throw new Error('First argument should be an instance of ArrayBuffer or Buffer');
        }

        this.arrayBuffer = buffer;
        this.metadata = new FLACMetadata();

        String.prototype.toUTF8 = function(str = null) {
            return new TextEncoder().encode(str ? str : this);
        };

        this._parseMetadata();

        return this;
    }

    /* unpack */
    _getBytesAsNumber            (array, start=0, end=array.length-start) {return Array.from(array.subarray(start, start+end)).reduce     ((result, b)=>result=256*result+b, 0);}
    _getBytesAsNumberLittleEndian(array, start=0, end=array.length-start) {return Array.from(array.subarray(start, start+end)).reduceRight((result, b)=>result=256*result+b, 0);}
    _getBytesAsHexString (array, start=0, end=array.length-start) {return Array.from(array.subarray(start, start+end)).map(n=>(n>>4).toString(16)+(n&0xF).toString(16)).join('')}
    _getBytesAsUTF8String(array, start=0, end=array.length-start) {return new TextDecoder().decode(array.subarray(start, start+end));}
    _getBlockType(number){
        switch (number) {
            case 0: return 'STREAMINFO';
            case 1: return 'PADDING';
            case 2: return 'APPLICATION';
            case 3: return 'SEEKTABLE';
            case 4: return 'VORBIS_COMMENT';
            case 5: return 'CUESHEET';
            case 6: return 'PICTURE';
            case 127: return 'invalid, to avoid confusion with a frame sync code';
            default: return 'reserved';
        }
    }
    _getPictureType(typeNumber){
        const types = [
            'Other',
            '32x32 pixels \'file icon\' (PNG only)',
            'Other file icon',
            'Cover (front)',
            'Cover (back)',
            'Leaflet page',
            'Media (e.g. label side of CD)',
            'Lead artist/lead performer/soloist',
            'Artist/performer',
            'Conductor',
            'Band/Orchestra',
            'Composer',
            'Lyricist/text writer',
            'Recording Location',
            'During recording',
            'During performance',
            'Movie/video screen capture',
            'A bright coloured fish',
            'Illustration',
            'Band/artist logotype',
            'Publisher/Studio logotype'
        ];
        return typeNumber<types.length ? types[typeNumber] : 'reserved';
    }
    /* pack */
    _uint32ToUint8Array(uint32) {
        const eightBitMask = 0xff;
        return [
            (uint32 >>> 24) & eightBitMask,
            (uint32 >>> 16) & eightBitMask,
            (uint32 >>> 8) & eightBitMask,
            uint32 & eightBitMask,
        ];
    }
    _uint24ToUint8Array(uint32) {
        const eightBitMask = 0xff;
        return [
            (uint32 >>> 16) & eightBitMask,
            (uint32 >>> 8) & eightBitMask,
            uint32 & eightBitMask,
        ];
    }
    _uint16ToUint8Array(uint32) {
        const eightBitMask = 0xff;
        return [
            (uint32 >>> 8) & eightBitMask,
            uint32 & eightBitMask,
        ];
    }
    _hexStringToUint8Array(str) {
        return str.replace(/(\w\w)/g,'$1,').slice(0,-1).split(',').map(s=> (parseInt(s[0],16)<<4) + parseInt(s[1],16));
    }

    get _vorbisComment() {
        let block = this.metadata.blocks.find(block=>block.blockType==='VORBIS_COMMENT');
        if (block)
            return block.data;
    }

    addComment(field, value = null) {
        if (field) {
            if (!value) {
                value = field.split('=')[1];
                field = field.split('=')[0];
            }
            field = field.toUpperCase();
            if (!this._vorbisComment.comments.hasOwnProperty(field))
                this._vorbisComment.comments[field] = new VorbisComment();
            if (!this._vorbisComment.comments[field].find(storedValue=> storedValue===value))
                this._vorbisComment.comments[field].push(value.toString());
        }
        return this;
    }
    removeComment(field = null, value = null) {
        if (!field) {
            Object.keys(this._vorbisComment.comments).forEach(key=> delete this._vorbisComment.comments[key]);
        } else {
            field = field.toUpperCase();
            if (!value) {
                delete this._vorbisComment.comments[field];
            } else {
                value = value.toString();
                if (this.hasOwnProperty(field))
                    this._vorbisComment.comments[field] = this._vorbisComment.comments[field].filter(storedValue=> storedValue!==value);
            }
        }
        return this;
    }
    getComment(field) {
        return this._vorbisComment.comments[field.toUpperCase()];
    }

    addPicture(buffer, APICType, MIMEType, ) {
        if (!buffer || typeof buffer !== 'object' || !('byteLength' in buffer)) {
            throw new Error('First argument should be an instance of ArrayBuffer or Buffer');
        }

    }



    _serializeMetadataBlock(block) {
        let bytes = new Uint8Array(block.serializedSize);
        let data = block.data;
        let offset = 0;

        switch (block.blockType) {
            case 'STREAMINFO':
                bytes.set(this._uint16ToUint8Array(data.minBlockSize));
                offset += 2;
                bytes.set(this._uint16ToUint8Array(data.maxBlockSize), offset);
                offset += 2;
                bytes.set(this._uint24ToUint8Array(data.minFrameSize), offset);
                offset += 3;
                bytes.set(this._uint24ToUint8Array(data.maxFrameSize), offset);
                offset += 3;
                bytes.set(this._uint24ToUint8Array((data.sampleRate<<4) + (data.numberOfChannels-1<<1) + (data.bitsPerSample-1>>4)), offset);
                offset += 3;
                bytes[offset] = (((data.bitsPerSample-1&0xF)<<4) + (Math.trunc(data.totalSamples/Math.pow(2,32))&0xF));
                offset += 1;
                bytes.set(this._uint32ToUint8Array(data.totalSamples), offset);
                offset += 4;
                bytes.set(this._hexStringToUint8Array(data.rawMD5), offset);
                break;
            case 'PADDING':
                break;
            case 'APPLICATION':
                bytes.set(data.applicationID.toUTF8());
                offset += 4;
                bytes.set(data.applicationData, offset);
                break;
            case 'SEEKTABLE':
                data.points.forEach(point=> {
                    bytes.set(this._hexStringToUint8Array(point.sampleNumber), offset);
                    bytes.set(this._hexStringToUint8Array(point.offset), offset+8);
                    bytes.set(this._hexStringToUint8Array(point.numberOfSamples), offset+16);
                    offset += 18;
                });
                break;
            case 'VORBIS_COMMENT':
                    bytes.set(this._uint32ToUint8Array(data.vendorString.toUTF8().length).reverse(), offset);
                offset += 4;
                bytes.set(data.vendorString.toUTF8(), offset);
                offset += data.vendorString.toUTF8().length;

                let comments = data.comments.toStringArray();
                bytes.set(this._uint32ToUint8Array(comments.length).reverse(), offset);
                offset += 4;
                comments.forEach(comment=> {
                    bytes.set(this._uint32ToUint8Array(comment.toUTF8().length).reverse(), offset);
                    offset += 4;
                    bytes.set(comment.toUTF8(), offset);
                    offset += comment.toUTF8().length;
                });
                break;
            case 'CUESHEET':
                break;
            case 'PICTURE':
                bytes.set(this._uint32ToUint8Array(data.APICtype));
                offset += 4;
                bytes.set(this._uint32ToUint8Array(data.MIMEType.toUTF8().length), offset);
                offset += 4;
                bytes.set(data.MIMEType.toUTF8(), offset);
                offset += data.MIMEType.toUTF8().length;

                bytes.set(this._uint32ToUint8Array(data.description.toUTF8().length), offset);
                offset += 4;
                bytes.set(data.description.toUTF8(), offset);
                offset += data.description.toUTF8().length;

                bytes.set(this._uint32ToUint8Array(data.width), offset);
                offset += 4;
                bytes.set(this._uint32ToUint8Array(data.height), offset);
                offset += 4;
                bytes.set(this._uint32ToUint8Array(data.colorDepth), offset);
                offset += 4;
                bytes.set(this._uint32ToUint8Array(data.colorNumber), offset);
                offset += 4;
                bytes.set(this._uint32ToUint8Array(data.data.length), offset);
                offset += 4;
                bytes.set(data.data, offset);
                break;
        }
        return bytes;
    }

    serializeMetadata() {
        let newMetadataLengthFull = 4+this.metadata.blocks.reduce((sum, block)=>sum+4+block.serializedSize, 0);
        let newSize = newMetadataLengthFull + ((this.arrayBuffer.byteLength>this.metadata.framesOffset)? this.arrayBuffer.byteLength-this.metadata.framesOffset : 0);

        let bytes = new Uint8Array(newSize);
        bytes.set(this.metadata.signature.toUTF8());

        let offset = 4;
        let lastBlock = false;
        this.metadata.blocks.forEach((block, n, blocks)=>{
            if (blocks.length-1 === n) lastBlock = true;
            bytes[offset] = block.blockTypeNubmer | (lastBlock<<7);
            offset += 1;
            bytes.set(this._uint24ToUint8Array(block.serializedSize), offset);
            offset += 3;

            bytes.set(this._serializeMetadataBlock(block), offset);
            offset += block.serializedSize;
        });

        // console.info('old meta size: %d, new: %d, delta: %d', this.metadata.framesOffset, newMetadataLengthFull, Math.abs(this.metadata.framesOffset-newMetadataLengthFull) );
        // console.info('old size: %d, new: %d, delta: %d', this.arrayBuffer.byteLength, newSize, Math.abs(this.arrayBuffer.byteLength-newSize) );
        // console.info('frames size: %d, to copy: %d', this.arrayBuffer.byteLength-this.metadata.framesOffset, new Uint8Array(this.arrayBuffer).subarray(this.metadata.framesOffset).length);
        // console.info('offset: %d', offset );

        bytes.set(new Uint8Array(this.arrayBuffer).subarray(this.metadata.framesOffset), offset);

        this.arrayBuffer = bytes.buffer;
        return this;
    }


    _parseMetadataBlock(array, arrayOffset, type, size) {
        let blockData = array.subarray(arrayOffset, arrayOffset+size);
        let offset = 0;
        let data = new FLACMetadataBlockData();
        switch (type) {
            case 'STREAMINFO':
                data.minBlockSize = this._getBytesAsNumber(blockData, offset, 2);
                offset += 2;
                data.maxBlockSize = this._getBytesAsNumber(blockData, offset, 2);
                offset += 2;
                data.minFrameSize = this._getBytesAsNumber(blockData, offset, 3);
                offset += 3;
                data.maxFrameSize = this._getBytesAsNumber(blockData, offset, 3);
                offset += 3;
                data.sampleRate = this._getBytesAsNumber(blockData, offset, 3)>>4;
                offset += 2;
                data.numberOfChannels = 1+ ((blockData[offset]>>1) &7);
                data.bitsPerSample = 1+ ((1&blockData[offset]) <<4) + (blockData[offset+1]>>4);
                offset += 1;
                data.totalSamples = (blockData[offset]&0xF)*Math.pow(2,32) + this._getBytesAsNumber(blockData, offset+1, 4);
                offset += 5;
                data.rawMD5 = this._getBytesAsHexString(blockData, offset, 16).toUpperCase();
                break;
            case 'PADDING':
                break;
            case 'APPLICATION':
                data.applicationID = this._getBytesAsUTF8String(blockData, offset, 4);
                offset += 4;
                data.applicationData = blockData.subarray(offset);
                break;
            case 'SEEKTABLE':
                data.pointCount = size/18;
                data.points = [];
                for (let i=0; i<data.pointCount; i++) {
                    data.points.push({
                        sampleNumber: this._getBytesAsHexString(blockData, offset, 8),
                        offset: this._getBytesAsHexString(blockData, offset+8, 8),
                        numberOfSamples: this._getBytesAsHexString(blockData, offset+16, 2)
                    });
                    offset += 18;
                }
                break;
            case 'VORBIS_COMMENT':
                let vendorLength = this._getBytesAsNumberLittleEndian(blockData, offset, 4);
                offset += 4;
                data.vendorString = this._getBytesAsUTF8String(blockData, offset, vendorLength);
                offset += vendorLength;

                let userCommentListLength = this._getBytesAsNumberLittleEndian(blockData, offset, 4);
                offset += 4;
                data.comments = new VorbisCommentPacket();

                let commentLength = 0;
                for (let i=0; i<userCommentListLength; i++) {
                    commentLength = this._getBytesAsNumberLittleEndian(blockData, offset, 4);
                    offset += 4;
                    data.comments._addComment(this._getBytesAsUTF8String(blockData, offset, commentLength));
                    offset += commentLength;
                }
                break;
            case 'CUESHEET':
                break;
            case 'PICTURE':
                data.APICtype = this._getBytesAsNumber(blockData, offset, 4);
                offset += 4;
                let MIMELength = this._getBytesAsNumber(blockData, offset, 4);
                offset += 4;
                data.MIMEType = this._getBytesAsUTF8String(blockData, offset, MIMELength);
                offset += MIMELength;
                let descriptionLength = this._getBytesAsNumber(blockData, offset, 4);
                offset += 4;
                data.description = this._getBytesAsUTF8String(blockData, offset, descriptionLength);
                offset += descriptionLength;
                data.width = this._getBytesAsNumber(blockData, offset, 4);
                offset += 4;
                data.height = this._getBytesAsNumber(blockData, offset, 4);
                offset += 4;
                data.colorDepth = this._getBytesAsNumber(blockData, offset, 4);
                offset += 4;
                data.colorNumber = this._getBytesAsNumber(blockData, offset, 4);
                offset += 4;
                let binarySize = this._getBytesAsNumber(blockData, offset, 4);
                offset += 4;
                data.data = blockData.subarray(offset, offset+binarySize);
                break;
        }
        return data;
    }

    _parseMetadata() {
        let bytes = new Uint8Array(this.arrayBuffer);

        this.metadata.signature = this._getBytesAsUTF8String(bytes,0,4);

        let offset = 4;
        let lastBlock = false;
        let block;

        let iteration = 0;
        while (!lastBlock && offset < bytes.length) {
            if (iteration++ > 42) throw new RangeError('Too much METADATA_BLOCKS. Looks like file corrupted');

            block = new FLACMetadataBlock();

            block.offset = offset;
            lastBlock = !!(bytes[offset] >> 7);
            block.blockTypeNubmer = bytes[offset] & 127;
            block.blockType = this._getBlockType(block.blockTypeNubmer);
            offset += 1;
            block.blockSize = this._getBytesAsNumber(bytes, offset, 3);
            offset += 3;
            block.data = this._parseMetadataBlock(bytes, offset, block.blockType, block.blockSize);
            offset += block.blockSize;

            // if (block.blockType !== 'PADDING')
                this.metadata.blocks.push(block);
        }
        this.metadata.framesOffset = offset;
        return this;
    }
}