Innovenergy_trunk/frontend/node_modules/pngjs/lib/bitmapper.js

257 lines
6.2 KiB
JavaScript

'use strict';
var interlaceUtils = require('./interlace');
var pixelBppMapper = [
// 0 - dummy entry
function() {},
// 1 - L
// 0: 0, 1: 0, 2: 0, 3: 0xff
function(pxData, data, pxPos, rawPos) {
if (rawPos === data.length) {
throw new Error('Ran out of data');
}
var pixel = data[rawPos];
pxData[pxPos] = pixel;
pxData[pxPos + 1] = pixel;
pxData[pxPos + 2] = pixel;
pxData[pxPos + 3] = 0xff;
},
// 2 - LA
// 0: 0, 1: 0, 2: 0, 3: 1
function(pxData, data, pxPos, rawPos) {
if (rawPos + 1 >= data.length) {
throw new Error('Ran out of data');
}
var pixel = data[rawPos];
pxData[pxPos] = pixel;
pxData[pxPos + 1] = pixel;
pxData[pxPos + 2] = pixel;
pxData[pxPos + 3] = data[rawPos + 1];
},
// 3 - RGB
// 0: 0, 1: 1, 2: 2, 3: 0xff
function(pxData, data, pxPos, rawPos) {
if (rawPos + 2 >= data.length) {
throw new Error('Ran out of data');
}
pxData[pxPos] = data[rawPos];
pxData[pxPos + 1] = data[rawPos + 1];
pxData[pxPos + 2] = data[rawPos + 2];
pxData[pxPos + 3] = 0xff;
},
// 4 - RGBA
// 0: 0, 1: 1, 2: 2, 3: 3
function(pxData, data, pxPos, rawPos) {
if (rawPos + 3 >= data.length) {
throw new Error('Ran out of data');
}
pxData[pxPos] = data[rawPos];
pxData[pxPos + 1] = data[rawPos + 1];
pxData[pxPos + 2] = data[rawPos + 2];
pxData[pxPos + 3] = data[rawPos + 3];
}
];
var pixelBppCustomMapper = [
// 0 - dummy entry
function() {},
// 1 - L
// 0: 0, 1: 0, 2: 0, 3: 0xff
function(pxData, pixelData, pxPos, maxBit) {
var pixel = pixelData[0];
pxData[pxPos] = pixel;
pxData[pxPos + 1] = pixel;
pxData[pxPos + 2] = pixel;
pxData[pxPos + 3] = maxBit;
},
// 2 - LA
// 0: 0, 1: 0, 2: 0, 3: 1
function(pxData, pixelData, pxPos) {
var pixel = pixelData[0];
pxData[pxPos] = pixel;
pxData[pxPos + 1] = pixel;
pxData[pxPos + 2] = pixel;
pxData[pxPos + 3] = pixelData[1];
},
// 3 - RGB
// 0: 0, 1: 1, 2: 2, 3: 0xff
function(pxData, pixelData, pxPos, maxBit) {
pxData[pxPos] = pixelData[0];
pxData[pxPos + 1] = pixelData[1];
pxData[pxPos + 2] = pixelData[2];
pxData[pxPos + 3] = maxBit;
},
// 4 - RGBA
// 0: 0, 1: 1, 2: 2, 3: 3
function(pxData, pixelData, pxPos) {
pxData[pxPos] = pixelData[0];
pxData[pxPos + 1] = pixelData[1];
pxData[pxPos + 2] = pixelData[2];
pxData[pxPos + 3] = pixelData[3];
}
];
function bitRetriever(data, depth) {
var leftOver = [];
var i = 0;
function split() {
if (i === data.length) {
throw new Error('Ran out of data');
}
var byte = data[i];
i++;
var byte8, byte7, byte6, byte5, byte4, byte3, byte2, byte1;
switch (depth) {
default:
throw new Error('unrecognised depth');
case 16:
byte2 = data[i];
i++;
leftOver.push(((byte << 8) + byte2));
break;
case 4:
byte2 = byte & 0x0f;
byte1 = byte >> 4;
leftOver.push(byte1, byte2);
break;
case 2:
byte4 = byte & 3;
byte3 = byte >> 2 & 3;
byte2 = byte >> 4 & 3;
byte1 = byte >> 6 & 3;
leftOver.push(byte1, byte2, byte3, byte4);
break;
case 1:
byte8 = byte & 1;
byte7 = byte >> 1 & 1;
byte6 = byte >> 2 & 1;
byte5 = byte >> 3 & 1;
byte4 = byte >> 4 & 1;
byte3 = byte >> 5 & 1;
byte2 = byte >> 6 & 1;
byte1 = byte >> 7 & 1;
leftOver.push(byte1, byte2, byte3, byte4, byte5, byte6, byte7, byte8);
break;
}
}
return {
get: function(count) {
while (leftOver.length < count) {
split();
}
var returner = leftOver.slice(0, count);
leftOver = leftOver.slice(count);
return returner;
},
resetAfterLine: function() {
leftOver.length = 0;
},
end: function() {
if (i !== data.length) {
throw new Error('extra data found');
}
}
};
}
function mapImage8Bit(image, pxData, getPxPos, bpp, data, rawPos) { // eslint-disable-line max-params
var imageWidth = image.width;
var imageHeight = image.height;
var imagePass = image.index;
for (var y = 0; y < imageHeight; y++) {
for (var x = 0; x < imageWidth; x++) {
var pxPos = getPxPos(x, y, imagePass);
pixelBppMapper[bpp](pxData, data, pxPos, rawPos);
rawPos += bpp; //eslint-disable-line no-param-reassign
}
}
return rawPos;
}
function mapImageCustomBit(image, pxData, getPxPos, bpp, bits, maxBit) { // eslint-disable-line max-params
var imageWidth = image.width;
var imageHeight = image.height;
var imagePass = image.index;
for (var y = 0; y < imageHeight; y++) {
for (var x = 0; x < imageWidth; x++) {
var pixelData = bits.get(bpp);
var pxPos = getPxPos(x, y, imagePass);
pixelBppCustomMapper[bpp](pxData, pixelData, pxPos, maxBit);
}
bits.resetAfterLine();
}
}
exports.dataToBitMap = function(data, bitmapInfo) {
var width = bitmapInfo.width;
var height = bitmapInfo.height;
var depth = bitmapInfo.depth;
var bpp = bitmapInfo.bpp;
var interlace = bitmapInfo.interlace;
if (depth !== 8) {
var bits = bitRetriever(data, depth);
}
var pxData;
if (depth <= 8) {
pxData = new Buffer(width * height * 4);
}
else {
pxData = new Uint16Array(width * height * 4);
}
var maxBit = Math.pow(2, depth) - 1;
var rawPos = 0;
var images;
var getPxPos;
if (interlace) {
images = interlaceUtils.getImagePasses(width, height);
getPxPos = interlaceUtils.getInterlaceIterator(width, height);
}
else {
var nonInterlacedPxPos = 0;
getPxPos = function() {
var returner = nonInterlacedPxPos;
nonInterlacedPxPos += 4;
return returner;
};
images = [{ width: width, height: height }];
}
for (var imageIndex = 0; imageIndex < images.length; imageIndex++) {
if (depth === 8) {
rawPos = mapImage8Bit(images[imageIndex], pxData, getPxPos, bpp, data, rawPos);
}
else {
mapImageCustomBit(images[imageIndex], pxData, getPxPos, bpp, bits, maxBit);
}
}
if (depth === 8) {
if (rawPos !== data.length) {
throw new Error('extra data found');
}
}
else {
bits.end();
}
return pxData;
};