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CMaps binary packing
This commit is contained in:
Yury Delendik
parent
e5cd75083f
commit
69efd9cb96
13 changed files with 1156 additions and 35 deletions
437
external/cmapscompress/compress.js
vendored
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437
external/cmapscompress/compress.js
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/* Copyright 2014 Mozilla Foundation
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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var fs = require('fs');
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var path = require('path');
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var parseAdobeCMap = require('./parse.js').parseAdobeCMap;
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var optimizeCMap = require('./optimize.js').optimizeCMap;
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function compressCmap(srcPath, destPath, verify) {
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var content = fs.readFileSync(srcPath).toString();
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var inputData = parseAdobeCMap(content);
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optimizeCMap(inputData);
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var out = writeByte((inputData.type << 1) | inputData.wmode);
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if (inputData.comment) {
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out += writeByte(0xE0) + writeString(inputData.comment);
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}
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if (inputData.usecmap) {
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out += writeByte(0xE1) + writeString(inputData.usecmap);
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}
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var i = 0;
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while (i < inputData.body.length) {
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var item = inputData.body[i++], subitems = item.items;
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var first = item.items[0];
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var sequence = item.sequence === true;
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var flags = (item.type << 5) | (sequence ? 0x10 : 0);
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var nextStart, nextCode;
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switch (item.type) {
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case 0:
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out += writeByte(flags | getHexSize(first.start)) + writeNumber(subitems.length);
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out += first.start + writeNumber(subHex(first.end, first.start));
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nextStart = incHex(first.end);
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for (var j = 1; j < subitems.length; j++) {
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out += writeNumber(subHex(subitems[j].start, nextStart)) +
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writeNumber(subHex(subitems[j].end, subitems[j].start));
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nextStart = incHex(subitems[j].end);
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}
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break;
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case 1:
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out += writeByte(flags | getHexSize(first.start)) + writeNumber(subitems.length);
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out += first.start + writeNumber(subHex(first.end, first.start)) + writeNumber(first.code);
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nextStart = incHex(first.end);
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for (var j = 1; j < subitems.length; j++) {
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out += writeNumber(subHex(subitems[j].start, nextStart)) +
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writeNumber(subHex(subitems[j].end, subitems[j].start)) +
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writeNumber(subitems[j].code);
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nextStart = incHex(subitems[j].end);
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}
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break;
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case 2:
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out += writeByte(flags | getHexSize(first.char)) + writeNumber(subitems.length);
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out += first.char + writeNumber(first.code);
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nextStart = incHex(first.char);
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nextCode = first.code + 1;
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for (var j = 1; j < subitems.length; j++) {
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out += (sequence ? '' : writeNumber(subHex(subitems[j].char, nextStart))) +
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writeSigned(subitems[j].code - nextCode);
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nextStart = incHex(subitems[j].char);
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nextCode = item.items[j].code + 1;
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}
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break;
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case 3:
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out += writeByte(flags | getHexSize(first.start)) + writeNumber(subitems.length);
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out += first.start + writeNumber(subHex(first.end, first.start)) + writeNumber(first.code);
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nextStart = incHex(first.end);
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for (var j = 1; j < subitems.length; j++) {
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out += (sequence ? '' : writeNumber(subHex(subitems[j].start, nextStart))) +
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writeNumber(subHex(subitems[j].end, subitems[j].start)) +
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writeNumber(subitems[j].code);
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nextStart = incHex(subitems[j].end);
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}
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break;
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case 4:
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out += writeByte(flags | getHexSize(first.code)) + writeNumber(subitems.length);
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out += first.char + first.code;
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nextStart = incHex(first.char);
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nextCode = incHex(first.code);
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for (var j = 1; j < subitems.length; j++) {
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out += (sequence ? '' : writeNumber(subHex(subitems[j].char, nextStart))) +
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writeSigned(subHex(subitems[j].code, nextCode));
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nextStart = incHex(subitems[j].char);
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nextCode = incHex(subitems[j].code);
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}
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break;
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case 5:
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out += writeByte(flags | getHexSize(first.code)) + writeNumber(subitems.length);
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out += first.start + writeNumber(subHex(first.end, first.start)) + first.code;
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nextStart = incHex(first.end);
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for (var j = 1; j < subitems.length; j++) {
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out += (sequence ? '' : writeNumber(subHex(subitems[j].start, nextStart))) +
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writeNumber(subHex(subitems[j].end, subitems[j].start)) +
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subitems[j].code;
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nextStart = incHex(subitems[j].end);
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}
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break;
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}
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}
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fs.writeFileSync(destPath, new Buffer(out, 'hex'));
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if (verify) {
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var result2 = parseCMap(out);
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var isGood = JSON.stringify(inputData) == JSON.stringify(result2);
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if (!isGood) {
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throw new Error('Extracted data does not match the expected result');
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}
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}
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return {
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orig: fs.statSync(srcPath).size,
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packed: out.length >> 1
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};
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}
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function parseCMap(binaryData) {
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var reader = {
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buffer: binaryData,
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pos: 0,
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end: binaryData.length,
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readByte: function () {
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if (this.pos >= this.end) {
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return -1;
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}
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var d1 = fromHexDigit(this.buffer[this.pos]);
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var d2 = fromHexDigit(this.buffer[this.pos + 1]);
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this.pos += 2;
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return (d1 << 4) | d2;
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},
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readNumber: function () {
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var n = 0;
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var last;
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do {
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var b = this.readByte();
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last = !(b & 0x80);
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n = (n << 7) | (b & 0x7F);
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} while (!last);
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return n;
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},
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readSigned: function () {
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var n = this.readNumber();
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return (n & 1) ? -(n >>> 1) - 1 : n >>> 1;
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},
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readHex: function (size) {
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var lengthInChars = (size + 1) << 1;
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var s = this.buffer.substr(this.pos, lengthInChars);
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this.pos += lengthInChars;
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return s;
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},
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readHexNumber: function (size) {
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var lengthInChars = (size + 1) << 1;
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var stack = [];
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do {
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var b = this.readByte();
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last = !(b & 0x80);
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stack.push(b & 0x7F);
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} while (!last);
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var s = '', buffer = 0, bufferSize = 0;
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while (s.length < lengthInChars) {
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while (bufferSize < 4 && stack.length > 0) {
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buffer = (stack.pop() << bufferSize) | buffer;
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bufferSize += 7;
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}
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s = toHexDigit(buffer & 15) + s;
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buffer >>= 4;
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bufferSize -= 4;
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}
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return s;
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},
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readHexSigned: function (size) {
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var num = this.readHexNumber(size);
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var sign = fromHexDigit(num[num.length - 1]) & 1 ? 15 : 0;
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var c = 0;
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var result = '';
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for (var i = 0; i < num.length; i++) {
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c = (c << 4) | fromHexDigit(num[i]);
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result += toHexDigit(sign ? (c >> 1) ^ sign : (c >> 1));
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c &= 1;
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}
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return result;
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},
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readString: function () {
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var len = this.readNumber();
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var s = '';
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for (var i = 0; i < len; i++) {
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s += String.fromCharCode(this.readNumber());
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}
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return s;
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}
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};
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var header = reader.readByte();
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var result = {
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type: header >> 1,
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wmode: header & 1,
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comment: null,
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usecmap: null,
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body: []
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};
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var b;
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while ((b = reader.readByte()) >= 0) {
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var type = b >> 5;
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if (type === 7) {
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switch (b & 0x1F) {
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case 0:
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result.comment = reader.readString();
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break;
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case 1:
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result.usecmap = reader.readString();
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break;
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}
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continue;
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}
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var sequence = !!(b & 0x10);
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var dataSize = b & 15;
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var subitems = [];
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var item = {
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type: type,
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items: subitems
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};
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if (sequence) {
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item.sequence = true;
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}
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var ucs2DataSize = 1;
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var subitemsCount = reader.readNumber();
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var start, end, code, char;
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switch (type) {
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case 0:
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start = reader.readHex(dataSize);
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end = addHex(reader.readHexNumber(dataSize), start);
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subitems.push({start: start, end: end});
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for (var i = 1; i < subitemsCount; i++) {
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start = addHex(reader.readHexNumber(dataSize), incHex(end));
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end = addHex(reader.readHexNumber(dataSize), start);
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subitems.push({start: start, end: end});
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}
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break;
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case 1:
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start = reader.readHex(dataSize);
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end = addHex(reader.readHexNumber(dataSize), start);
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code = reader.readNumber();
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subitems.push({start: start, end: end, code: code});
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for (var i = 1; i < subitemsCount; i++) {
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start = addHex(reader.readHexNumber(dataSize), incHex(end));
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end = addHex(reader.readHexNumber(dataSize), start);
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code = reader.readNumber();
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subitems.push({start: start, end: end, code: code});
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}
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break;
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case 2:
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char = reader.readHex(dataSize);
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code = reader.readNumber();
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subitems.push({char: char, code: code});
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for (var i = 1; i < subitemsCount; i++) {
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char = sequence ? incHex(char) : addHex(reader.readHexNumber(dataSize), incHex(char));
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code = reader.readSigned() + (code + 1);
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subitems.push({char: char, code: code});
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}
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break;
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case 3:
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start = reader.readHex(dataSize);
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end = addHex(reader.readHexNumber(dataSize), start);
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code = reader.readNumber();
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subitems.push({start: start, end: end, code: code});
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for (var i = 1; i < subitemsCount; i++) {
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start = sequence ? incHex(end) : addHex(reader.readHexNumber(dataSize), incHex(end));
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end = addHex(reader.readHexNumber(dataSize), start);
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code = reader.readNumber();
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subitems.push({start: start, end: end, code: code});
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}
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break;
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case 4:
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char = reader.readHex(ucs2DataSize);
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code = reader.readHex(dataSize);
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subitems.push({char: char, code: code});
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for (var i = 1; i < subitemsCount; i++) {
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char = sequence ? incHex(char) : addHex(reader.readHexNumber(ucs2DataSize), incHex(char));
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code = addHex(reader.readHexSigned(dataSize), incHex(code));
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subitems.push({char: char, code: code});
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}
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break;
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case 5:
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start = reader.readHex(ucs2DataSize);
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end = addHex(reader.readHexNumber(ucs2DataSize), start);
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code = reader.readHex(dataSize);
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subitems.push({start: start, end: end, code: code});
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for (var i = 1; i < subitemsCount; i++) {
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start = sequence ? incHex(end) : addHex(reader.readHexNumber(ucs2DataSize), incHex(end));
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end = addHex(reader.readHexNumber(ucs2DataSize), start);
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code = reader.readHex(dataSize);
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subitems.push({start: start, end: end, code: code});
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}
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break;
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default:
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throw new Error('Unknown type: ' + type)
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}
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result.body.push(item);
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}
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return result;
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}
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function toHexDigit(n) {
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return n.toString(16);
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}
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function fromHexDigit(s) {
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return parseInt(s, 16);
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}
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function getHexSize(s) {
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return (s.length >> 1) - 1;
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}
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function writeByte(b) {
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return toHexDigit((b >> 4) & 15) + toHexDigit(b & 15);
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}
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function writeNumber(n) {
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if (typeof n === 'string') {
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var s = '', buffer = 0, bufferSize = 0;
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var i = n.length;
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while (i > 0) {
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--i;
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buffer = (fromHexDigit(n[i]) << bufferSize) | buffer;
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bufferSize += 4;
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if (bufferSize >= 7) {
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s = writeByte((buffer & 0x7f) | (s.length > 0 ? 0x80 : 0)) + s;
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buffer >>>= 7;
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bufferSize -= 7;
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}
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}
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if (buffer > 0) {
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s = writeByte((buffer & 0x7f) | (s.length > 0 ? 0x80 : 0)) + s;
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}
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while (s.indexOf('80') === 0) {
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s = s.substr(2);
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}
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return s;
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} else {
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var s = writeByte(n & 0x7F);
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n >>>= 7;
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while (n > 0) {
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s = writeByte((n & 0x7F) | 0x80) + s;
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n >>>= 7;
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}
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return s;
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}
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}
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function writeSigned(n) {
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if (typeof n === 'string') {
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var t = '';
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var c = fromHexDigit(n[0]);
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var neg = c >= 8;
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c = neg ? (c ^ 15) : c;
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for (var i = 1; i < n.length; i++) {
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var d = fromHexDigit(n[i]);
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c = (c << 4) | (neg ? (d ^ 15) : d);
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t += toHexDigit(c >> 3);
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c = c & 7;
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}
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t += toHexDigit((c << 1) | (neg ? 1 : 0));
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return writeNumber(t);
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}
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return n < 0 ? writeNumber(-2 * n - 1) : writeNumber(2 * n);
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}
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function writeString(s) {
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var t = writeNumber(s.length);
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for (var i = 0; i < s.length; i++) {
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t += writeNumber(s.charCodeAt(i));
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}
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return t;
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}
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function addHex(a, b) {
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var c = 0, s = '';
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for (var i = a.length - 1; i >= 0; i--) {
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c += fromHexDigit(a[i]) + fromHexDigit(b[i]);
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if (c >= 16) {
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s = toHexDigit(c - 16) + s;
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c = 1;
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} else {
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s = toHexDigit(c) + s;
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c = 0;
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}
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}
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return s;
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}
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function subHex(a, b) {
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var c = 0, s = '';
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for (var i = a.length - 1; i >= 0; i--) {
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c += fromHexDigit(a[i]) - fromHexDigit(b[i]);
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if (c < 0) {
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s = toHexDigit(c + 16) + s;
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c = -1;
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} else {
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s = toHexDigit(c) + s;
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c = 0;
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}
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}
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return s;
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}
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function incHex(a) {
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var c = 1, s = '';
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for (var i = a.length - 1; i >= 0; i--) {
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c += fromHexDigit(a[i]);
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if (c >= 16) {
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s = toHexDigit(c - 16) + s;
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c = 1;
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} else {
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s = toHexDigit(c) + s;
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c = 0;
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}
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}
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return s;
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}
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exports.compressCmaps = function (src, dest, verify) {
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var files = fs.readdirSync(src).filter(function (fn) {
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return fn.indexOf('.') < 0; // skipping files with the extension
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});
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files.forEach(function (fn) {
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var srcPath = path.join(src, fn);
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var destPath = path.join(dest, fn + '.bcmap');
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var stats = compressCmap(srcPath, destPath, verify);
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console.log('Compressing ' + fn + ': ' + stats.orig + ' vs ' + stats.packed +
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' ' + (stats.packed / stats.orig * 100).toFixed(1) + '%');
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});
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};
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