JS FLACMetadataEditor

Allows you to edit metadata of FLAC files. CO

当前为 2018-04-13 提交的版本,查看 最新版本

此脚本不应直接安装。它是供其他脚本使用的外部库,要使用该库请加入元指令 // @require https://update.greasyfork.org/scripts/40545/265001/JS%20FLACMetadataEditor.js

您需要先安装一个扩展,例如 篡改猴Greasemonkey暴力猴,之后才能安装此脚本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安装一个扩展,例如 篡改猴暴力猴,之后才能安装此脚本。

您需要先安装一个扩展,例如 篡改猴Userscripts ,之后才能安装此脚本。

您需要先安装一款用户脚本管理器扩展,例如 Tampermonkey,才能安装此脚本。

您需要先安装用户脚本管理器扩展后才能安装此脚本。

(我已经安装了用户脚本管理器,让我安装!)

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

(我已经安装了用户样式管理器,让我安装!)

// ==UserScript==
// @description Allows you to edit metadata of FLAC files. CO
// @name        JS FLACMetadataEditor
// @namespace   universe.earth.www.ahohnmyc
// @version     0.0.2
// @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';
        }
    }
    /* 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) {
                let splitted = field.split('=');
                if (!splitted[1]) return this;
                value = splitted[1];
                field = splitted[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(dataInput) {
        if (!dataInput.data || !dataInput.data || typeof dataInput.data !== 'object' || !('byteLength' in dataInput.data)) {
            throw new Error('Field "data" should be an instance of ArrayBuffer or Buffer');
        }
        dataInput.data = new Uint8Array(dataInput.data);

        const dataDefault = {
            APICtype: 3,
            MIMEType: 'image/jpeg',
            colorDepth: 0,
            colorNumber: 0,
            data: new Uint8Array([]),
            description: '',
            width: 0,
            height: 0,
        };

        let block = new FLACMetadataBlock();
        block.blockTypeNubmer = 6;
        block.blockType = 'PICTURE';
        for (let property in dataDefault) {
            if (dataInput[property]) {
                block.data[property] = dataInput[property];
            } else {
                block.data[property] = dataDefault[property];
            }
        }

        let bl = this.metadata.blocks;
        let index = bl.length;
        if (bl[bl.length-1].blockType === 'PADDING') index--;

        bl.splice(index, 0, block);
        this.metadata.blocks = bl;

        return this;
    }



    _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;
    }
}