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node_modules/png-js/png.js | 560 lines | 17.0 KiB | application/javascript | JavascriptGenshiLexer |
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move datatable to yarn
 r789 /*
* MIT LICENSE
* Copyright (c) 2011 Devon Govett
*
* 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:
*
* The above copyright notice and this permission notice shall be included in all copies or
* substantial portions of the Software.
*
* 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.
*/
window.PNG = (function() {
let APNG_DISPOSE_OP_NONE = 0;
let APNG_DISPOSE_OP_BACKGROUND = 1;
let APNG_DISPOSE_OP_PREVIOUS = 2;
let APNG_BLEND_OP_SOURCE = 0;
let APNG_BLEND_OP_OVER = 1;
let scratchCanvas = document.createElement('canvas');
let scratchCtx = scratchCanvas.getContext('2d');
let makeImage = function(imageData) {
scratchCtx.width = imageData.width;
scratchCtx.height = imageData.height;
scratchCtx.clearRect(0, 0, imageData.width, imageData.height);
scratchCtx.putImageData(imageData, 0, 0);
const img = new Image();
img.src = scratchCanvas.toDataURL();
return img;
};
class PNG {
static load(url, canvas, callback) {
if (typeof canvas === 'function') {
callback = canvas;
}
const xhr = new XMLHttpRequest();
xhr.open('GET', url, true);
xhr.responseType = 'arraybuffer';
xhr.onload = () => {
const data = new Uint8Array(xhr.response || xhr.mozResponseArrayBuffer);
const png = new PNG(data);
if (typeof (canvas && canvas.getContext) === 'function') {
png.render(canvas);
}
return typeof callback === 'function' ? callback(png) : undefined;
};
return xhr.send(null);
}
constructor(data1) {
let i;
this.data = data1;
this.pos = 8; // Skip the default header
this.palette = [];
this.imgData = [];
this.transparency = {};
this.animation = null;
this.text = {};
let frame = null;
while (true) {
var data;
let chunkSize = this.readUInt32();
let section = '';
for (i = 0; i < 4; i++) {
section += String.fromCharCode(this.data[this.pos++]);
}
switch (section) {
case 'IHDR':
// we can grab interesting values from here (like width, height, etc)
this.width = this.readUInt32();
this.height = this.readUInt32();
this.bits = this.data[this.pos++];
this.colorType = this.data[this.pos++];
this.compressionMethod = this.data[this.pos++];
this.filterMethod = this.data[this.pos++];
this.interlaceMethod = this.data[this.pos++];
break;
case 'acTL':
// we have an animated PNG
this.animation = {
numFrames: this.readUInt32(),
numPlays: this.readUInt32() || Infinity,
frames: []
};
break;
case 'PLTE':
this.palette = this.read(chunkSize);
break;
case 'fcTL':
if (frame) {
this.animation.frames.push(frame);
}
this.pos += 4; // skip sequence number
frame = {
width: this.readUInt32(),
height: this.readUInt32(),
xOffset: this.readUInt32(),
yOffset: this.readUInt32()
};
var delayNum = this.readUInt16();
var delayDen = this.readUInt16() || 100;
frame.delay = (1000 * delayNum) / delayDen;
frame.disposeOp = this.data[this.pos++];
frame.blendOp = this.data[this.pos++];
frame.data = [];
break;
case 'IDAT':
case 'fdAT':
if (section === 'fdAT') {
this.pos += 4; // skip sequence number
chunkSize -= 4;
}
data = (frame && frame.data) || this.imgData;
for (i = 0; i < chunkSize; i++) {
data.push(this.data[this.pos++]);
}
break;
case 'tRNS':
// This chunk can only occur once and it must occur after the
// PLTE chunk and before the IDAT chunk.
this.transparency = {};
switch (this.colorType) {
case 3:
// Indexed color, RGB. Each byte in this chunk is an alpha for
// the palette index in the PLTE ("palette") chunk up until the
// last non-opaque entry. Set up an array, stretching over all
// palette entries which will be 0 (opaque) or 1 (transparent).
this.transparency.indexed = this.read(chunkSize);
var short = 255 - this.transparency.indexed.length;
if (short > 0) {
for (i = 0; i < short; i++) {
this.transparency.indexed.push(255);
}
}
break;
case 0:
// Greyscale. Corresponding to entries in the PLTE chunk.
// Grey is two bytes, range 0 .. (2 ^ bit-depth) - 1
this.transparency.grayscale = this.read(chunkSize)[0];
break;
case 2:
// True color with proper alpha channel.
this.transparency.rgb = this.read(chunkSize);
break;
}
break;
case 'tEXt':
var text = this.read(chunkSize);
var index = text.indexOf(0);
var key = String.fromCharCode.apply(String, text.slice(0, index));
this.text[key] = String.fromCharCode.apply(
String,
text.slice(index + 1)
);
break;
case 'IEND':
if (frame) {
this.animation.frames.push(frame);
}
// we've got everything we need!
switch (this.colorType) {
case 0:
case 3:
case 4:
this.colors = 1;
break;
case 2:
case 6:
this.colors = 3;
break;
}
this.hasAlphaChannel = [4, 6].includes(this.colorType);
var colors = this.colors + (this.hasAlphaChannel ? 1 : 0);
this.pixelBitlength = this.bits * colors;
switch (this.colors) {
case 1:
this.colorSpace = 'DeviceGray';
break;
case 3:
this.colorSpace = 'DeviceRGB';
break;
}
this.imgData = new Uint8Array(this.imgData);
return;
break;
default:
// unknown (or unimportant) section, skip it
this.pos += chunkSize;
}
this.pos += 4; // Skip the CRC
if (this.pos > this.data.length) {
throw new Error('Incomplete or corrupt PNG file');
}
}
}
read(bytes) {
const result = new Array(bytes);
for (let i = 0; i < bytes; i++) {
result[i] = this.data[this.pos++];
}
return result;
}
readUInt32() {
const b1 = this.data[this.pos++] << 24;
const b2 = this.data[this.pos++] << 16;
const b3 = this.data[this.pos++] << 8;
const b4 = this.data[this.pos++];
return b1 | b2 | b3 | b4;
}
readUInt16() {
const b1 = this.data[this.pos++] << 8;
const b2 = this.data[this.pos++];
return b1 | b2;
}
decodePixels(data) {
if (data == null) {
data = this.imgData;
}
if (data.length === 0) {
return new Uint8Array(0);
}
data = new FlateStream(data);
data = data.getBytes();
const { width, height } = this;
const pixelBytes = this.pixelBitlength / 8;
const pixels = new Uint8Array(width * height * pixelBytes);
const { length } = data;
let pos = 0;
function pass(x0, y0, dx, dy, singlePass = false) {
const w = Math.ceil((width - x0) / dx);
const h = Math.ceil((height - y0) / dy);
const scanlineLength = pixelBytes * w;
const buffer = singlePass ? pixels : new Uint8Array(scanlineLength * h);
let row = 0;
let c = 0;
while (row < h && pos < length) {
var byte, col, i, left, upper;
switch (data[pos++]) {
case 0: // None
for (i = 0; i < scanlineLength; i++) {
buffer[c++] = data[pos++];
}
break;
case 1: // Sub
for (i = 0; i < scanlineLength; i++) {
byte = data[pos++];
left = i < pixelBytes ? 0 : buffer[c - pixelBytes];
buffer[c++] = (byte + left) % 256;
}
break;
case 2: // Up
for (i = 0; i < scanlineLength; i++) {
byte = data[pos++];
col = (i - (i % pixelBytes)) / pixelBytes;
upper =
row &&
buffer[
(row - 1) * scanlineLength +
col * pixelBytes +
(i % pixelBytes)
];
buffer[c++] = (upper + byte) % 256;
}
break;
case 3: // Average
for (i = 0; i < scanlineLength; i++) {
byte = data[pos++];
col = (i - (i % pixelBytes)) / pixelBytes;
left = i < pixelBytes ? 0 : buffer[c - pixelBytes];
upper =
row &&
buffer[
(row - 1) * scanlineLength +
col * pixelBytes +
(i % pixelBytes)
];
buffer[c++] = (byte + Math.floor((left + upper) / 2)) % 256;
}
break;
case 4: // Paeth
for (i = 0; i < scanlineLength; i++) {
var paeth, upperLeft;
byte = data[pos++];
col = (i - (i % pixelBytes)) / pixelBytes;
left = i < pixelBytes ? 0 : buffer[c - pixelBytes];
if (row === 0) {
upper = upperLeft = 0;
} else {
upper =
buffer[
(row - 1) * scanlineLength +
col * pixelBytes +
(i % pixelBytes)
];
upperLeft =
col &&
buffer[
(row - 1) * scanlineLength +
(col - 1) * pixelBytes +
(i % pixelBytes)
];
}
const p = left + upper - upperLeft;
const pa = Math.abs(p - left);
const pb = Math.abs(p - upper);
const pc = Math.abs(p - upperLeft);
if (pa <= pb && pa <= pc) {
paeth = left;
} else if (pb <= pc) {
paeth = upper;
} else {
paeth = upperLeft;
}
buffer[c++] = (byte + paeth) % 256;
}
break;
default:
throw new Error(`Invalid filter algorithm: ${data[pos - 1]}`);
}
if (!singlePass) {
let pixelsPos = ((y0 + row * dy) * width + x0) * pixelBytes;
let bufferPos = row * scanlineLength;
for (i = 0; i < w; i++) {
for (let j = 0; j < pixelBytes; j++)
pixels[pixelsPos++] = buffer[bufferPos++];
pixelsPos += (dx - 1) * pixelBytes;
}
}
row++;
}
}
if (this.interlaceMethod === 1) {
/*
1 6 4 6 2 6 4 6
7 7 7 7 7 7 7 7
5 6 5 6 5 6 5 6
7 7 7 7 7 7 7 7
3 6 4 6 3 6 4 6
7 7 7 7 7 7 7 7
5 6 5 6 5 6 5 6
7 7 7 7 7 7 7 7
*/
pass(0, 0, 8, 8); // 1
pass(4, 0, 8, 8); // 2
pass(0, 4, 4, 8); // 3
pass(2, 0, 4, 4); // 4
pass(0, 2, 2, 4); // 5
pass(1, 0, 2, 2); // 6
pass(0, 1, 1, 2); // 7
} else {
pass(0, 0, 1, 1, true);
}
return pixels;
}
decodePalette() {
const { palette } = this;
const { length } = palette;
const transparency = this.transparency.indexed || [];
const ret = new Uint8Array((transparency.length || 0) + length);
let pos = 0;
let c = 0;
for (let i = 0; i < length; i += 3) {
var left;
ret[pos++] = palette[i];
ret[pos++] = palette[i + 1];
ret[pos++] = palette[i + 2];
ret[pos++] = (left = transparency[c++]) != null ? left : 255;
}
return ret;
}
copyToImageData(imageData, pixels) {
let j, k;
let { colors } = this;
let palette = null;
let alpha = this.hasAlphaChannel;
if (this.palette.length) {
palette =
this._decodedPalette || (this._decodedPalette = this.decodePalette());
colors = 4;
alpha = true;
}
const data = imageData.data || imageData;
const { length } = data;
const input = palette || pixels;
let i = (j = 0);
if (colors === 1) {
while (i < length) {
k = palette ? pixels[i / 4] * 4 : j;
const v = input[k++];
data[i++] = v;
data[i++] = v;
data[i++] = v;
data[i++] = alpha ? input[k++] : 255;
j = k;
}
} else {
while (i < length) {
k = palette ? pixels[i / 4] * 4 : j;
data[i++] = input[k++];
data[i++] = input[k++];
data[i++] = input[k++];
data[i++] = alpha ? input[k++] : 255;
j = k;
}
}
}
decode() {
const ret = new Uint8Array(this.width * this.height * 4);
this.copyToImageData(ret, this.decodePixels());
return ret;
}
decodeFrames(ctx) {
if (!this.animation) {
return;
}
for (let i = 0; i < this.animation.frames.length; i++) {
const frame = this.animation.frames[i];
const imageData = ctx.createImageData(frame.width, frame.height);
const pixels = this.decodePixels(new Uint8Array(frame.data));
this.copyToImageData(imageData, pixels);
frame.imageData = imageData;
frame.image = makeImage(imageData);
}
}
renderFrame(ctx, number) {
const { frames } = this.animation;
const frame = frames[number];
const prev = frames[number - 1];
// if we're on the first frame, clear the canvas
if (number === 0) {
ctx.clearRect(0, 0, this.width, this.height);
}
// check the previous frame's dispose operation
if ((prev && prev.disposeOp) === APNG_DISPOSE_OP_BACKGROUND) {
ctx.clearRect(prev.xOffset, prev.yOffset, prev.width, prev.height);
} else if ((prev && prev.disposeOp) === APNG_DISPOSE_OP_PREVIOUS) {
ctx.putImageData(prev.imageData, prev.xOffset, prev.yOffset);
}
// APNG_BLEND_OP_SOURCE overwrites the previous data
if (frame.blendOp === APNG_BLEND_OP_SOURCE) {
ctx.clearRect(frame.xOffset, frame.yOffset, frame.width, frame.height);
}
// draw the current frame
return ctx.drawImage(frame.image, frame.xOffset, frame.yOffset);
}
animate(ctx) {
let frameNumber = 0;
const { numFrames, frames, numPlays } = this.animation;
const doFrame = () => {
const f = frameNumber++ % numFrames;
const frame = frames[f];
this.renderFrame(ctx, f);
if (numFrames > 1 && frameNumber / numFrames < numPlays) {
this.animation._timeout = setTimeout(doFrame, frame.delay);
}
};
doFrame();
}
stopAnimation() {
return clearTimeout(this.animation && this.animation._timeout);
}
render(canvas) {
// if this canvas was displaying another image before,
// stop the animation on it
if (canvas._png) {
canvas._png.stopAnimation();
}
canvas._png = this;
canvas.width = this.width;
canvas.height = this.height;
const ctx = canvas.getContext('2d');
if (this.animation) {
this.decodeFrames(ctx);
return this.animate(ctx);
} else {
const data = ctx.createImageData(this.width, this.height);
this.copyToImageData(data, this.decodePixels());
return ctx.putImageData(data, 0, 0);
}
}
}
return PNG;
})();