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| author | Cash Costello <cash.costello@gmail.com> | 2010-10-24 21:08:27 +0000 |
|---|---|---|
| committer | Cash Costello <cash.costello@gmail.com> | 2010-10-24 21:08:27 +0000 |
| commit | da1493b95a2f0b5000a487ae373c9318c58d0b2d (patch) | |
| tree | a339b053ade9fb15a1717bdf248a59afc9b3d239 /vendors/uploadify/com/adobe/images/PNGEncoder.as | |
| parent | 5161b1c8fdc8ff69005f864a89127fc18db6d4ed (diff) | |
| download | elgg-da1493b95a2f0b5000a487ae373c9318c58d0b2d.tar.gz elgg-da1493b95a2f0b5000a487ae373c9318c58d0b2d.tar.bz2 | |
partial implementation of flash uploader
Diffstat (limited to 'vendors/uploadify/com/adobe/images/PNGEncoder.as')
| -rw-r--r-- | vendors/uploadify/com/adobe/images/PNGEncoder.as | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/vendors/uploadify/com/adobe/images/PNGEncoder.as b/vendors/uploadify/com/adobe/images/PNGEncoder.as new file mode 100644 index 000000000..83c95f629 --- /dev/null +++ b/vendors/uploadify/com/adobe/images/PNGEncoder.as @@ -0,0 +1,141 @@ +/*
+ Copyright (c) 2008, Adobe Systems Incorporated
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are
+ met:
+
+ * Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+ * Neither the name of Adobe Systems Incorporated nor the names of its
+ contributors may be used to endorse or promote products derived from
+ this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+package com.adobe.images
+{
+ import flash.geom.*;
+ import flash.display.Bitmap;
+ import flash.display.BitmapData;
+ import flash.utils.ByteArray;
+
+ /**
+ * Class that converts BitmapData into a valid PNG
+ */
+ public class PNGEncoder
+ {
+ /**
+ * Created a PNG image from the specified BitmapData
+ *
+ * @param image The BitmapData that will be converted into the PNG format.
+ * @return a ByteArray representing the PNG encoded image data.
+ * @langversion ActionScript 3.0
+ * @playerversion Flash 9.0
+ * @tiptext
+ */
+ public static function encode(img:BitmapData):ByteArray {
+ // Create output byte array
+ var png:ByteArray = new ByteArray();
+ // Write PNG signature
+ png.writeUnsignedInt(0x89504e47);
+ png.writeUnsignedInt(0x0D0A1A0A);
+ // Build IHDR chunk
+ var IHDR:ByteArray = new ByteArray();
+ IHDR.writeInt(img.width);
+ IHDR.writeInt(img.height);
+ IHDR.writeUnsignedInt(0x08060000); // 32bit RGBA
+ IHDR.writeByte(0);
+ writeChunk(png,0x49484452,IHDR);
+ // Build IDAT chunk
+ var IDAT:ByteArray= new ByteArray();
+ for(var i:int=0;i < img.height;i++) {
+ // no filter
+ IDAT.writeByte(0);
+ var p:uint;
+ var j:int;
+ if ( !img.transparent ) {
+ for(j=0;j < img.width;j++) {
+ p = img.getPixel(j,i);
+ IDAT.writeUnsignedInt(
+ uint(((p&0xFFFFFF) << 8)|0xFF));
+ }
+ } else {
+ for(j=0;j < img.width;j++) {
+ p = img.getPixel32(j,i);
+ IDAT.writeUnsignedInt(
+ uint(((p&0xFFFFFF) << 8)|
+ (p>>>24)));
+ }
+ }
+ }
+ IDAT.compress();
+ writeChunk(png,0x49444154,IDAT);
+ // Build IEND chunk
+ writeChunk(png,0x49454E44,null);
+ // return PNG
+ return png;
+ }
+
+ private static var crcTable:Array;
+ private static var crcTableComputed:Boolean = false;
+
+ private static function writeChunk(png:ByteArray,
+ type:uint, data:ByteArray):void {
+ if (!crcTableComputed) {
+ crcTableComputed = true;
+ crcTable = [];
+ var c:uint;
+ for (var n:uint = 0; n < 256; n++) {
+ c = n;
+ for (var k:uint = 0; k < 8; k++) {
+ if (c & 1) {
+ c = uint(uint(0xedb88320) ^
+ uint(c >>> 1));
+ } else {
+ c = uint(c >>> 1);
+ }
+ }
+ crcTable[n] = c;
+ }
+ }
+ var len:uint = 0;
+ if (data != null) {
+ len = data.length;
+ }
+ png.writeUnsignedInt(len);
+ var p:uint = png.position;
+ png.writeUnsignedInt(type);
+ if ( data != null ) {
+ png.writeBytes(data);
+ }
+ var e:uint = png.position;
+ png.position = p;
+ c = 0xffffffff;
+ for (var i:int = 0; i < (e-p); i++) {
+ c = uint(crcTable[
+ (c ^ png.readUnsignedByte()) &
+ uint(0xff)] ^ uint(c >>> 8));
+ }
+ c = uint(c^uint(0xffffffff));
+ png.position = e;
+ png.writeUnsignedInt(c);
+ }
+ }
+}
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