+++ /dev/null
-/*\r
- Copyright (c) 2008, Adobe Systems Incorporated\r
- All rights reserved.\r
-\r
- Redistribution and use in source and binary forms, with or without \r
- modification, are permitted provided that the following conditions are\r
- met:\r
-\r
- * Redistributions of source code must retain the above copyright notice, \r
- this list of conditions and the following disclaimer.\r
- \r
- * Redistributions in binary form must reproduce the above copyright\r
- notice, this list of conditions and the following disclaimer in the \r
- documentation and/or other materials provided with the distribution.\r
- \r
- * Neither the name of Adobe Systems Incorporated nor the names of its \r
- contributors may be used to endorse or promote products derived from \r
- this software without specific prior written permission.\r
-\r
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS\r
- IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,\r
- THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR\r
- PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR \r
- CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,\r
- EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,\r
- PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR\r
- PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF\r
- LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING\r
- NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS\r
- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\r
-*/\r
-package com.adobe.images\r
-{\r
- import flash.geom.*;\r
- import flash.display.Bitmap;\r
- import flash.display.BitmapData;\r
- import flash.utils.ByteArray;\r
-\r
- /**\r
- * Class that converts BitmapData into a valid PNG\r
- */ \r
- public class PNGEncoder\r
- {\r
- /**\r
- * Created a PNG image from the specified BitmapData\r
- *\r
- * @param image The BitmapData that will be converted into the PNG format.\r
- * @return a ByteArray representing the PNG encoded image data.\r
- * @langversion ActionScript 3.0\r
- * @playerversion Flash 9.0\r
- * @tiptext\r
- */ \r
- public static function encode(img:BitmapData):ByteArray {\r
- // Create output byte array\r
- var png:ByteArray = new ByteArray();\r
- // Write PNG signature\r
- png.writeUnsignedInt(0x89504e47);\r
- png.writeUnsignedInt(0x0D0A1A0A);\r
- // Build IHDR chunk\r
- var IHDR:ByteArray = new ByteArray();\r
- IHDR.writeInt(img.width);\r
- IHDR.writeInt(img.height);\r
- IHDR.writeUnsignedInt(0x08060000); // 32bit RGBA\r
- IHDR.writeByte(0);\r
- writeChunk(png,0x49484452,IHDR);\r
- // Build IDAT chunk\r
- var IDAT:ByteArray= new ByteArray();\r
- for(var i:int=0;i < img.height;i++) {\r
- // no filter\r
- IDAT.writeByte(0);\r
- var p:uint;\r
- var j:int;\r
- if ( !img.transparent ) {\r
- for(j=0;j < img.width;j++) {\r
- p = img.getPixel(j,i);\r
- IDAT.writeUnsignedInt(\r
- uint(((p&0xFFFFFF) << 8)|0xFF));\r
- }\r
- } else {\r
- for(j=0;j < img.width;j++) {\r
- p = img.getPixel32(j,i);\r
- IDAT.writeUnsignedInt(\r
- uint(((p&0xFFFFFF) << 8)|\r
- (p>>>24)));\r
- }\r
- }\r
- }\r
- IDAT.compress();\r
- writeChunk(png,0x49444154,IDAT);\r
- // Build IEND chunk\r
- writeChunk(png,0x49454E44,null);\r
- // return PNG\r
- return png;\r
- }\r
- \r
- private static var crcTable:Array;\r
- private static var crcTableComputed:Boolean = false;\r
- \r
- private static function writeChunk(png:ByteArray, \r
- type:uint, data:ByteArray):void {\r
- if (!crcTableComputed) {\r
- crcTableComputed = true;\r
- crcTable = [];\r
- var c:uint;\r
- for (var n:uint = 0; n < 256; n++) {\r
- c = n;\r
- for (var k:uint = 0; k < 8; k++) {\r
- if (c & 1) {\r
- c = uint(uint(0xedb88320) ^ \r
- uint(c >>> 1));\r
- } else {\r
- c = uint(c >>> 1);\r
- }\r
- }\r
- crcTable[n] = c;\r
- }\r
- }\r
- var len:uint = 0;\r
- if (data != null) {\r
- len = data.length;\r
- }\r
- png.writeUnsignedInt(len);\r
- var p:uint = png.position;\r
- png.writeUnsignedInt(type);\r
- if ( data != null ) {\r
- png.writeBytes(data);\r
- }\r
- var e:uint = png.position;\r
- png.position = p;\r
- c = 0xffffffff;\r
- for (var i:int = 0; i < (e-p); i++) {\r
- c = uint(crcTable[\r
- (c ^ png.readUnsignedByte()) & \r
- uint(0xff)] ^ uint(c >>> 8));\r
- }\r
- c = uint(c^uint(0xffffffff));\r
- png.position = e;\r
- png.writeUnsignedInt(c);\r
- }\r
- }\r
-}
\ No newline at end of file