first commit

node_modules/pngjs/lib/packer-async.js

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+"use strict";
+
+let util = require("util");
+let Stream = require("stream");
+let constants = require("./constants");
+let Packer = require("./packer");
+
+let PackerAsync = (module.exports = function (opt) {
+  Stream.call(this);
+
+  let options = opt || {};
+
+  this._packer = new Packer(options);
+  this._deflate = this._packer.createDeflate();
+
+  this.readable = true;
+});
+util.inherits(PackerAsync, Stream);
+
+PackerAsync.prototype.pack = function (data, width, height, gamma) {
+  // Signature
+  this.emit("data", Buffer.from(constants.PNG_SIGNATURE));
+  this.emit("data", this._packer.packIHDR(width, height));
+
+  if (gamma) {
+    this.emit("data", this._packer.packGAMA(gamma));
+  }
+
+  let filteredData = this._packer.filterData(data, width, height);
+
+  // compress it
+  this._deflate.on("error", this.emit.bind(this, "error"));
+
+  this._deflate.on(
+    "data",
+    function (compressedData) {
+      this.emit("data", this._packer.packIDAT(compressedData));
+    }.bind(this)
+  );
+
+  this._deflate.on(
+    "end",
+    function () {
+      this.emit("data", this._packer.packIEND());
+      this.emit("end");
+    }.bind(this)
+  );
+
+  this._deflate.end(filteredData);
+};