chore: add mobile app

frontend-admin/node_modules/pngjs/lib/packer-async.js

@@ -0,0 +1,45 @@
+'use strict';
+
+var util = require('util');
+var Stream = require('stream');
+var constants = require('./constants');
+var Packer = require('./packer');
+
+var PackerAsync = module.exports = function(opt) {
+  Stream.call(this);
+
+  var 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', new Buffer(constants.PNG_SIGNATURE));
+  this.emit('data', this._packer.packIHDR(width, height));
+
+  if (gamma) {
+    this.emit('data', this._packer.packGAMA(gamma));
+  }
+
+  var 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);
+};