Icard/angular-clarity-master(work.../node_modules/pngjs/lib/png.js

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2024-07-16 14:55:36 +00:00
"use strict";
let util = require("util");
let Stream = require("stream");
let Parser = require("./parser-async");
let Packer = require("./packer-async");
let PNGSync = require("./png-sync");
let PNG = (exports.PNG = function (options) {
Stream.call(this);
options = options || {}; // eslint-disable-line no-param-reassign
// coerce pixel dimensions to integers (also coerces undefined -> 0):
this.width = options.width | 0;
this.height = options.height | 0;
this.data =
this.width > 0 && this.height > 0
? Buffer.alloc(4 * this.width * this.height)
: null;
if (options.fill && this.data) {
this.data.fill(0);
}
this.gamma = 0;
this.readable = this.writable = true;
this._parser = new Parser(options);
this._parser.on("error", this.emit.bind(this, "error"));
this._parser.on("close", this._handleClose.bind(this));
this._parser.on("metadata", this._metadata.bind(this));
this._parser.on("gamma", this._gamma.bind(this));
this._parser.on(
"parsed",
function (data) {
this.data = data;
this.emit("parsed", data);
}.bind(this)
);
this._packer = new Packer(options);
this._packer.on("data", this.emit.bind(this, "data"));
this._packer.on("end", this.emit.bind(this, "end"));
this._parser.on("close", this._handleClose.bind(this));
this._packer.on("error", this.emit.bind(this, "error"));
});
util.inherits(PNG, Stream);
PNG.sync = PNGSync;
PNG.prototype.pack = function () {
if (!this.data || !this.data.length) {
this.emit("error", "No data provided");
return this;
}
process.nextTick(
function () {
this._packer.pack(this.data, this.width, this.height, this.gamma);
}.bind(this)
);
return this;
};
PNG.prototype.parse = function (data, callback) {
if (callback) {
let onParsed, onError;
onParsed = function (parsedData) {
this.removeListener("error", onError);
this.data = parsedData;
callback(null, this);
}.bind(this);
onError = function (err) {
this.removeListener("parsed", onParsed);
callback(err, null);
}.bind(this);
this.once("parsed", onParsed);
this.once("error", onError);
}
this.end(data);
return this;
};
PNG.prototype.write = function (data) {
this._parser.write(data);
return true;
};
PNG.prototype.end = function (data) {
this._parser.end(data);
};
PNG.prototype._metadata = function (metadata) {
this.width = metadata.width;
this.height = metadata.height;
this.emit("metadata", metadata);
};
PNG.prototype._gamma = function (gamma) {
this.gamma = gamma;
};
PNG.prototype._handleClose = function () {
if (!this._parser.writable && !this._packer.readable) {
this.emit("close");
}
};
PNG.bitblt = function (src, dst, srcX, srcY, width, height, deltaX, deltaY) {
// eslint-disable-line max-params
// coerce pixel dimensions to integers (also coerces undefined -> 0):
/* eslint-disable no-param-reassign */
srcX |= 0;
srcY |= 0;
width |= 0;
height |= 0;
deltaX |= 0;
deltaY |= 0;
/* eslint-enable no-param-reassign */
if (
srcX > src.width ||
srcY > src.height ||
srcX + width > src.width ||
srcY + height > src.height
) {
throw new Error("bitblt reading outside image");
}
if (
deltaX > dst.width ||
deltaY > dst.height ||
deltaX + width > dst.width ||
deltaY + height > dst.height
) {
throw new Error("bitblt writing outside image");
}
for (let y = 0; y < height; y++) {
src.data.copy(
dst.data,
((deltaY + y) * dst.width + deltaX) << 2,
((srcY + y) * src.width + srcX) << 2,
((srcY + y) * src.width + srcX + width) << 2
);
}
};
PNG.prototype.bitblt = function (
dst,
srcX,
srcY,
width,
height,
deltaX,
deltaY
) {
// eslint-disable-line max-params
PNG.bitblt(this, dst, srcX, srcY, width, height, deltaX, deltaY);
return this;
};
PNG.adjustGamma = function (src) {
if (src.gamma) {
for (let y = 0; y < src.height; y++) {
for (let x = 0; x < src.width; x++) {
let idx = (src.width * y + x) << 2;
for (let i = 0; i < 3; i++) {
let sample = src.data[idx + i] / 255;
sample = Math.pow(sample, 1 / 2.2 / src.gamma);
src.data[idx + i] = Math.round(sample * 255);
}
}
}
src.gamma = 0;
}
};
PNG.prototype.adjustGamma = function () {
PNG.adjustGamma(this);
};