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‎.gitignore

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node_modules
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*.hdr

‎LICENSE

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Copyright (C) 2013 Jon-Carlos Rivera
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Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

‎lib/color.js

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var expTable = Array.apply(null, new Array(256)).map(function (v,i) { return Math.pow(2, i - 128);});
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module.exports = {
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toFloatArray: function(r, g, b, e) {
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if (e === 0) return [0, 0, 0, 0];
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var m = expTable[e];
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return [r / 256 * m, g / 256 * m, b / 256 * m];
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}
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};

‎lib/hdr-read.js

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var stream = require('stream'),
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util = require('util'),
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colorUtil = require('./color');
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module.exports = HDRReader;
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var MINLEN = 8,
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MAXLEN = 0x7fff,
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HEADER_REGEX = /([\#\?]+)?([^=\n\r]+)?=?([^=\n\r]*)?([\n\r]+)/gi,
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DIMENSION_REGEX = /([+\-])([XY])\s(\d+)\s([+\-])([XY])\s(\d+)/i,
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HEADER_PREFIXES = {
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'#?': 'FILETYPE',
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'#': 'COMMENT',
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'undefined': 'HEADER'
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};
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function HDRReader (options) {
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if (!options) options = {};
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if (!options.highWaterMark) options.highWaterMark = 65536;
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stream.Writable.call(this, options);
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this.headers = {};
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this.comments = [];
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this.data = [];
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this.width = 0;
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this.height = 0;
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this._lastChunk = null;
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this._headerFinished = false;
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this._startOfScanline = true;
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this._newRLEScanline = false;
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this._row_major = true;
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this._scanlineSize = 0;
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}
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util.inherits(HDRReader, stream.Writable);
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HDRReader.prototype._write = function (chunk, encoding, next) {
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if (this._lastChunk) {
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this._lastChunk = Buffer.concat([this._lastChunk, chunk]);
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} else {
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this._lastChunk = chunk;
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}
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if (!this._headerFinished) {
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this._readHeader(this._lastChunk, encoding);
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return next();
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}
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while (this._lastChunk.length >= this._scanlineSize) {
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// this._processChunk(next);
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this._readScanline(this._lastChunk);
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}
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// this._copyRemainingBuffer(this._lastChunk, 0);
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return next();
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}
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HDRReader.prototype.end = function (chunk, encoding) {
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if (this._lastChunk) {
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if (chunk) this._lastChunk = Buffer.concat([this._lastChunk, chunk]);
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while (this._lastChunk.length > 0) {
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this._readScanline(this._lastChunk);
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}
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}
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this.emit('load');
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}
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HDRReader.prototype._processChunk = function (next) {
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if (this._lastChunk.length >= this._scanlineSize) {
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this._readScanline(this._lastChunk);
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return setImmediate(this._processChunk.bind(this, next));
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} else {
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this._copyRemainingBuffer(this._lastChunk, 0);
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return next();
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}
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}
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HDRReader.prototype._readScanline = function (chunk) {
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var firstPixel = [],
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scanline;
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firstPixel[0] = chunk.readUInt8(0);
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firstPixel[1] = chunk.readUInt8(1);
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firstPixel[2] = chunk.readUInt8(2);
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firstPixel[3] = chunk.readUInt8(3);
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if (this._isOldRLE(firstPixel)) {
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scanline = this._readOldRLE(chunk);
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} else {
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scanline = this._readNewRLE(chunk.slice(4))
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}
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firstPixel = null;
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if (this._row_major) {
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for (var i = this._start_x; i !== this._end_x; i += this._inc_x) {
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this._writePixel(i, this._current_y, colorUtil.toFloatArray.apply(null, scanline.shift()));
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}
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this._current_y += this._inc_y;
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} else {
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for (var i = this._start_y; i !== this._end_y; i += this._inc_y) {
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this._writePixel(this._current_x, i, colorUtil.toFloatArray.apply(null, scanline.shift()));
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}
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this._current_x += this._inc_x;
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}
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}
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HDRReader.prototype._readOldRLE = function (chunk) {
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var scanline = [],
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len = this._getScanlinePixels(),
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offset = 0,
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writePos = 0,
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i, rshift = 0;
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while (len > 0) {
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scanline[writePos] = [];
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scanline[writePos][0] = chunk.readUInt8(offset++);
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scanline[writePos][1] = chunk.readUInt8(offset++);
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scanline[writePos][2] = chunk.readUInt8(offset++);
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scanline[writePos][3] = chunk.readUInt8(offset++);
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if (scanline[writePos][0] === 1 &&
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scanline[writePos][1] === 1 &&
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scanline[writePos][2] === 1) {
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for (i = scanline[writePos][3] << rshift; i > 0; i--) {
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scanline[writePos] = [];
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scanline[writePos][0] = scanline[writePos - 1][0];
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scanline[writePos][1] = scanline[writePos - 1][1];
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scanline[writePos][2] = scanline[writePos - 1][2];
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scanline[writePos][3] = scanline[writePos - 1][3];
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writePos++;
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len--;
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}
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rshift += 8;
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}
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else {
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writePos++;
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len--;
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rshift = 0;
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}
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}
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this._trimRemainingBuffer(chunk, offset);
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return scanline;
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}
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HDRReader.prototype._readNewRLE = function (chunk) {
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var scanline = [],
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offset = 0;
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for (var i = 0; i < 4; i++) {
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for (var j = 0; j < this._getScanlinePixels(); ) {
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var code = chunk.readUInt8(offset++);
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if (code > 128) { // run
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code &= 127;
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var val = chunk.readUInt8(offset++);
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while (code--) {
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if (scanline[j] == null) scanline[j] = [];
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scanline[j++][i] = val;
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}
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} else { // non-run
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while(code--) {
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if (scanline[j] == null) scanline[j] = [];
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scanline[j++][i] = chunk.readUInt8(offset++);
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}
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}
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}
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}
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this._trimRemainingBuffer(chunk, offset);
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return scanline;
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}
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HDRReader.prototype._copyRemainingBuffer = function (chunk, consumed) {
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var remainingLen = chunk.length - consumed;
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this._lastChunk = new Buffer(remainingLen);
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chunk.copy(this._lastChunk, 0, consumed);
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// this._lastChunk = chunk.slice(consumed);
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}
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HDRReader.prototype._trimRemainingBuffer = function (chunk, consumed) {
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this._lastChunk = chunk.slice(consumed);
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}
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HDRReader.prototype._writePixel = function (x, y, pixelData) {
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var offset = (x + y * this.width) * 3;
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this.data[offset++] = pixelData[0];
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this.data[offset++] = pixelData[1];
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this.data[offset++] = pixelData[2];
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}
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HDRReader.prototype._readHeader = function (chunk) {
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var str = chunk.toString('ascii'),
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sliceOffset = 0,
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headerData;
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while (headerData = HEADER_REGEX.exec(str)) {
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sliceOffset += headerData[0].length;
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if (DIMENSION_REGEX.test(headerData[2])) {
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// Parse size header
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this._readSizeHeader(headerData[2]);
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this._headerFinished = true;
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break;
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} else {
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switch (HEADER_PREFIXES[String(headerData[1])]) {
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case 'FILETYPE':
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this.headers['RADIANCE'] = true;
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break;
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case 'HEADER':
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this.headers[headerData[2]] = this._processHeader(headerData[2], headerData[3]);
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break;
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case 'COMMENT':
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this.comments.push(headerData[2]);
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break;
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default:
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}
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}
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}
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this._trimRemainingBuffer(chunk, sliceOffset);
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}
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HDRReader.prototype._processHeader = function (headerName, headerValue) {
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switch (headerName.toUpperCase()) {
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case 'EXPOSURE':
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var val = parseFloat(headerValue);
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return ('EXPOSURE' in this.headers) ? this.headers['EXPOSURE'] * val : val;
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case 'COLORCORR':
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var vals = headerValue.split(/\s+/);
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vals = vals.map(parseFloat);
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return ('COLORCORR' in this.headers) ? this.headers['COLORCORR'].map(mults(vals)) : vals;
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default:
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return headerValue;
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}
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}
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HDRReader.prototype._isOldRLE = function (pixel) {
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var len = this._getScanlinePixels();
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if (len < MINLEN || len > MAXLEN) return true;
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if (pixel[0] !== 2) return true;
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if (pixel[1] !== 2 || pixel[2] & 128) return true;
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return false;
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}
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HDRReader.prototype._getScanlinePixels = function() {
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if (this._row_major) {
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return this.width;
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} else {
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return this.height;
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}
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}
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HDRReader.prototype._readSizeHeader = function(header) {
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var sizeData = header.match(DIMENSION_REGEX);
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if (sizeData[2].toLowerCase() === "y") {
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this._row_major = true;
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this.height = +sizeData[3];
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if (sizeData[1] === '-') {
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this._start_y = 0;
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this._end_y = this.height;
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this._inc_y = 1;
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this._current_y = this._start_y;
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} else {
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this._start_y = this.height - 1;
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this._end_y = -1;
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this._inc_y = -1;
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this._current_y = this._start_y;
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}
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this.width = +sizeData[6];
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if (sizeData[4] === '-') {
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this._start_x = this.width - 1;
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this._end_x = -1;
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this._inc_x = -1;
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this._current_x = this._start_x;
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} else {
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this._start_x = 0;
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this._end_x = this.width;
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this._inc_x = 1;
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this._current_x = this._start_x;
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}
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} else {
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this._row_major = false;
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this.width = +sizeData[3];
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if (sizeData[1] === '-') {
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this._start_x = 0;
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this._end_x = this.width;
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this._inc_x = 1;
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this._current_y = this._start_y;
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} else {
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this._start_x = this.width - 1;
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this._end_x = -1;
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this._inc_x = -1;
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this._current_x = this._start_x;
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}
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this.height = +sizeData[6];
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if (sizeData[4] === '-') {
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this._start_y = this.height - 1;
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this._end_y = -1;
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this._inc_y = -1;
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this._current_y = this._start_y;
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} else {
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this._start_y = 0;
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this._end_y = this.height;
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this._inc_y = 1;
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this._current_x = this._start_x;
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}
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}
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this._scanlineSize = this._getScanlinePixels() * 4 + 4; // Number of pixels + possible special pixel at beginning
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}
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function mults (m) {
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return function (v, i) {
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return m[i] * v;
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};
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}

‎lib/hdr.js

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module.exports = {
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reader: require('./hdr-read.js')
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}

‎package.json

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{
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"name": "hdr",
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"description": "Utilities for reading HDR image files",
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"version": "1.0.0",
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"homepage": "https://github.com/imbcmdth/hdr",
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"repository": {
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"type": "git",
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"url": "git://github.com/imbcmdth/hdr.git"
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},
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"author": {
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"name": "Jon-Carlos Rivera",
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"email": "[email protected]",
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"url": "http://jon-carlos.com"
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},
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"keywords": [
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"high dynamic range",
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"hdr"
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],
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"main": "./lib/hdr",
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"devDependencies": {
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"mocha": "1.8.1"
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},
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"scripts": {
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"test": "./node_modules/mocha/bin/mocha test"
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},
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"license": "MIT"
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}

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