--- /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.*;\r
+ import flash.utils.*;\r
+ \r
+ /**\r
+ * Class that converts BitmapData into a valid JPEG\r
+ */ \r
+ public class JPGEncoder\r
+ {\r
+\r
+ // Static table initialization\r
+ \r
+ private var ZigZag:Array = [\r
+ 0, 1, 5, 6,14,15,27,28,\r
+ 2, 4, 7,13,16,26,29,42,\r
+ 3, 8,12,17,25,30,41,43,\r
+ 9,11,18,24,31,40,44,53,\r
+ 10,19,23,32,39,45,52,54,\r
+ 20,22,33,38,46,51,55,60,\r
+ 21,34,37,47,50,56,59,61,\r
+ 35,36,48,49,57,58,62,63\r
+ ];\r
+ \r
+ private var YTable:Array = new Array(64);\r
+ private var UVTable:Array = new Array(64);\r
+ private var fdtbl_Y:Array = new Array(64);\r
+ private var fdtbl_UV:Array = new Array(64);\r
+ \r
+ private function initQuantTables(sf:int):void\r
+ {\r
+ var i:int;\r
+ var t:Number;\r
+ var YQT:Array = [\r
+ 16, 11, 10, 16, 24, 40, 51, 61,\r
+ 12, 12, 14, 19, 26, 58, 60, 55,\r
+ 14, 13, 16, 24, 40, 57, 69, 56,\r
+ 14, 17, 22, 29, 51, 87, 80, 62,\r
+ 18, 22, 37, 56, 68,109,103, 77,\r
+ 24, 35, 55, 64, 81,104,113, 92,\r
+ 49, 64, 78, 87,103,121,120,101,\r
+ 72, 92, 95, 98,112,100,103, 99\r
+ ];\r
+ for (i = 0; i < 64; i++) {\r
+ t = Math.floor((YQT[i]*sf+50)/100);\r
+ if (t < 1) {\r
+ t = 1;\r
+ } else if (t > 255) {\r
+ t = 255;\r
+ }\r
+ YTable[ZigZag[i]] = t;\r
+ }\r
+ var UVQT:Array = [\r
+ 17, 18, 24, 47, 99, 99, 99, 99,\r
+ 18, 21, 26, 66, 99, 99, 99, 99,\r
+ 24, 26, 56, 99, 99, 99, 99, 99,\r
+ 47, 66, 99, 99, 99, 99, 99, 99,\r
+ 99, 99, 99, 99, 99, 99, 99, 99,\r
+ 99, 99, 99, 99, 99, 99, 99, 99,\r
+ 99, 99, 99, 99, 99, 99, 99, 99,\r
+ 99, 99, 99, 99, 99, 99, 99, 99\r
+ ];\r
+ for (i = 0; i < 64; i++) {\r
+ t = Math.floor((UVQT[i]*sf+50)/100);\r
+ if (t < 1) {\r
+ t = 1;\r
+ } else if (t > 255) {\r
+ t = 255;\r
+ }\r
+ UVTable[ZigZag[i]] = t;\r
+ }\r
+ var aasf:Array = [\r
+ 1.0, 1.387039845, 1.306562965, 1.175875602,\r
+ 1.0, 0.785694958, 0.541196100, 0.275899379\r
+ ];\r
+ i = 0;\r
+ for (var row:int = 0; row < 8; row++)\r
+ {\r
+ for (var col:int = 0; col < 8; col++)\r
+ {\r
+ fdtbl_Y[i] = (1.0 / (YTable [ZigZag[i]] * aasf[row] * aasf[col] * 8.0));\r
+ fdtbl_UV[i] = (1.0 / (UVTable[ZigZag[i]] * aasf[row] * aasf[col] * 8.0));\r
+ i++;\r
+ }\r
+ }\r
+ }\r
+ \r
+ private var YDC_HT:Array;\r
+ private var UVDC_HT:Array;\r
+ private var YAC_HT:Array;\r
+ private var UVAC_HT:Array;\r
+ \r
+ private function computeHuffmanTbl(nrcodes:Array, std_table:Array):Array\r
+ {\r
+ var codevalue:int = 0;\r
+ var pos_in_table:int = 0;\r
+ var HT:Array = new Array();\r
+ for (var k:int=1; k<=16; k++) {\r
+ for (var j:int=1; j<=nrcodes[k]; j++) {\r
+ HT[std_table[pos_in_table]] = new BitString();\r
+ HT[std_table[pos_in_table]].val = codevalue;\r
+ HT[std_table[pos_in_table]].len = k;\r
+ pos_in_table++;\r
+ codevalue++;\r
+ }\r
+ codevalue*=2;\r
+ }\r
+ return HT;\r
+ }\r
+ \r
+ private var std_dc_luminance_nrcodes:Array = [0,0,1,5,1,1,1,1,1,1,0,0,0,0,0,0,0];\r
+ private var std_dc_luminance_values:Array = [0,1,2,3,4,5,6,7,8,9,10,11];\r
+ private var std_ac_luminance_nrcodes:Array = [0,0,2,1,3,3,2,4,3,5,5,4,4,0,0,1,0x7d];\r
+ private var std_ac_luminance_values:Array = [\r
+ 0x01,0x02,0x03,0x00,0x04,0x11,0x05,0x12,\r
+ 0x21,0x31,0x41,0x06,0x13,0x51,0x61,0x07,\r
+ 0x22,0x71,0x14,0x32,0x81,0x91,0xa1,0x08,\r
+ 0x23,0x42,0xb1,0xc1,0x15,0x52,0xd1,0xf0,\r
+ 0x24,0x33,0x62,0x72,0x82,0x09,0x0a,0x16,\r
+ 0x17,0x18,0x19,0x1a,0x25,0x26,0x27,0x28,\r
+ 0x29,0x2a,0x34,0x35,0x36,0x37,0x38,0x39,\r
+ 0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,\r
+ 0x4a,0x53,0x54,0x55,0x56,0x57,0x58,0x59,\r
+ 0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,\r
+ 0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,\r
+ 0x7a,0x83,0x84,0x85,0x86,0x87,0x88,0x89,\r
+ 0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,\r
+ 0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,\r
+ 0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,0xb5,0xb6,\r
+ 0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,\r
+ 0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,\r
+ 0xd5,0xd6,0xd7,0xd8,0xd9,0xda,0xe1,0xe2,\r
+ 0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,\r
+ 0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,\r
+ 0xf9,0xfa\r
+ ];\r
+ \r
+ private var std_dc_chrominance_nrcodes:Array = [0,0,3,1,1,1,1,1,1,1,1,1,0,0,0,0,0];\r
+ private var std_dc_chrominance_values:Array = [0,1,2,3,4,5,6,7,8,9,10,11];\r
+ private var std_ac_chrominance_nrcodes:Array = [0,0,2,1,2,4,4,3,4,7,5,4,4,0,1,2,0x77];\r
+ private var std_ac_chrominance_values:Array = [\r
+ 0x00,0x01,0x02,0x03,0x11,0x04,0x05,0x21,\r
+ 0x31,0x06,0x12,0x41,0x51,0x07,0x61,0x71,\r
+ 0x13,0x22,0x32,0x81,0x08,0x14,0x42,0x91,\r
+ 0xa1,0xb1,0xc1,0x09,0x23,0x33,0x52,0xf0,\r
+ 0x15,0x62,0x72,0xd1,0x0a,0x16,0x24,0x34,\r
+ 0xe1,0x25,0xf1,0x17,0x18,0x19,0x1a,0x26,\r
+ 0x27,0x28,0x29,0x2a,0x35,0x36,0x37,0x38,\r
+ 0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,\r
+ 0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,\r
+ 0x59,0x5a,0x63,0x64,0x65,0x66,0x67,0x68,\r
+ 0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,\r
+ 0x79,0x7a,0x82,0x83,0x84,0x85,0x86,0x87,\r
+ 0x88,0x89,0x8a,0x92,0x93,0x94,0x95,0x96,\r
+ 0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,\r
+ 0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,\r
+ 0xb5,0xb6,0xb7,0xb8,0xb9,0xba,0xc2,0xc3,\r
+ 0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,\r
+ 0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,\r
+ 0xe2,0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,\r
+ 0xea,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,\r
+ 0xf9,0xfa\r
+ ];\r
+ \r
+ private function initHuffmanTbl():void\r
+ {\r
+ YDC_HT = computeHuffmanTbl(std_dc_luminance_nrcodes,std_dc_luminance_values);\r
+ UVDC_HT = computeHuffmanTbl(std_dc_chrominance_nrcodes,std_dc_chrominance_values);\r
+ YAC_HT = computeHuffmanTbl(std_ac_luminance_nrcodes,std_ac_luminance_values);\r
+ UVAC_HT = computeHuffmanTbl(std_ac_chrominance_nrcodes,std_ac_chrominance_values);\r
+ }\r
+ \r
+ private var bitcode:Array = new Array(65535);\r
+ private var category:Array = new Array(65535);\r
+ \r
+ private function initCategoryNumber():void\r
+ {\r
+ var nrlower:int = 1;\r
+ var nrupper:int = 2;\r
+ var nr:int;\r
+ for (var cat:int=1; cat<=15; cat++) {\r
+ //Positive numbers\r
+ for (nr=nrlower; nr<nrupper; nr++) {\r
+ category[32767+nr] = cat;\r
+ bitcode[32767+nr] = new BitString();\r
+ bitcode[32767+nr].len = cat;\r
+ bitcode[32767+nr].val = nr;\r
+ }\r
+ //Negative numbers\r
+ for (nr=-(nrupper-1); nr<=-nrlower; nr++) {\r
+ category[32767+nr] = cat;\r
+ bitcode[32767+nr] = new BitString();\r
+ bitcode[32767+nr].len = cat;\r
+ bitcode[32767+nr].val = nrupper-1+nr;\r
+ }\r
+ nrlower <<= 1;\r
+ nrupper <<= 1;\r
+ }\r
+ }\r
+ \r
+ // IO functions\r
+ \r
+ private var byteout:ByteArray;\r
+ private var bytenew:int = 0;\r
+ private var bytepos:int = 7;\r
+ \r
+ private function writeBits(bs:BitString):void\r
+ {\r
+ var value:int = bs.val;\r
+ var posval:int = bs.len-1;\r
+ while ( posval >= 0 ) {\r
+ if (value & uint(1 << posval) ) {\r
+ bytenew |= uint(1 << bytepos);\r
+ }\r
+ posval--;\r
+ bytepos--;\r
+ if (bytepos < 0) {\r
+ if (bytenew == 0xFF) {\r
+ writeByte(0xFF);\r
+ writeByte(0);\r
+ }\r
+ else {\r
+ writeByte(bytenew);\r
+ }\r
+ bytepos=7;\r
+ bytenew=0;\r
+ }\r
+ }\r
+ }\r
+ \r
+ private function writeByte(value:int):void\r
+ {\r
+ byteout.writeByte(value);\r
+ }\r
+ \r
+ private function writeWord(value:int):void\r
+ {\r
+ writeByte((value>>8)&0xFF);\r
+ writeByte((value )&0xFF);\r
+ }\r
+ \r
+ // DCT & quantization core\r
+ \r
+ private function fDCTQuant(data:Array, fdtbl:Array):Array\r
+ {\r
+ var tmp0:Number, tmp1:Number, tmp2:Number, tmp3:Number, tmp4:Number, tmp5:Number, tmp6:Number, tmp7:Number;\r
+ var tmp10:Number, tmp11:Number, tmp12:Number, tmp13:Number;\r
+ var z1:Number, z2:Number, z3:Number, z4:Number, z5:Number, z11:Number, z13:Number;\r
+ var i:int;\r
+ /* Pass 1: process rows. */\r
+ var dataOff:int=0;\r
+ for (i=0; i<8; i++) {\r
+ tmp0 = data[dataOff+0] + data[dataOff+7];\r
+ tmp7 = data[dataOff+0] - data[dataOff+7];\r
+ tmp1 = data[dataOff+1] + data[dataOff+6];\r
+ tmp6 = data[dataOff+1] - data[dataOff+6];\r
+ tmp2 = data[dataOff+2] + data[dataOff+5];\r
+ tmp5 = data[dataOff+2] - data[dataOff+5];\r
+ tmp3 = data[dataOff+3] + data[dataOff+4];\r
+ tmp4 = data[dataOff+3] - data[dataOff+4];\r
+ \r
+ /* Even part */\r
+ tmp10 = tmp0 + tmp3; /* phase 2 */\r
+ tmp13 = tmp0 - tmp3;\r
+ tmp11 = tmp1 + tmp2;\r
+ tmp12 = tmp1 - tmp2;\r
+ \r
+ data[dataOff+0] = tmp10 + tmp11; /* phase 3 */\r
+ data[dataOff+4] = tmp10 - tmp11;\r
+ \r
+ z1 = (tmp12 + tmp13) * 0.707106781; /* c4 */\r
+ data[dataOff+2] = tmp13 + z1; /* phase 5 */\r
+ data[dataOff+6] = tmp13 - z1;\r
+ \r
+ /* Odd part */\r
+ tmp10 = tmp4 + tmp5; /* phase 2 */\r
+ tmp11 = tmp5 + tmp6;\r
+ tmp12 = tmp6 + tmp7;\r
+ \r
+ /* The rotator is modified from fig 4-8 to avoid extra negations. */\r
+ z5 = (tmp10 - tmp12) * 0.382683433; /* c6 */\r
+ z2 = 0.541196100 * tmp10 + z5; /* c2-c6 */\r
+ z4 = 1.306562965 * tmp12 + z5; /* c2+c6 */\r
+ z3 = tmp11 * 0.707106781; /* c4 */\r
+ \r
+ z11 = tmp7 + z3; /* phase 5 */\r
+ z13 = tmp7 - z3;\r
+ \r
+ data[dataOff+5] = z13 + z2; /* phase 6 */\r
+ data[dataOff+3] = z13 - z2;\r
+ data[dataOff+1] = z11 + z4;\r
+ data[dataOff+7] = z11 - z4;\r
+ \r
+ dataOff += 8; /* advance pointer to next row */\r
+ }\r
+ \r
+ /* Pass 2: process columns. */\r
+ dataOff = 0;\r
+ for (i=0; i<8; i++) {\r
+ tmp0 = data[dataOff+ 0] + data[dataOff+56];\r
+ tmp7 = data[dataOff+ 0] - data[dataOff+56];\r
+ tmp1 = data[dataOff+ 8] + data[dataOff+48];\r
+ tmp6 = data[dataOff+ 8] - data[dataOff+48];\r
+ tmp2 = data[dataOff+16] + data[dataOff+40];\r
+ tmp5 = data[dataOff+16] - data[dataOff+40];\r
+ tmp3 = data[dataOff+24] + data[dataOff+32];\r
+ tmp4 = data[dataOff+24] - data[dataOff+32];\r
+ \r
+ /* Even part */\r
+ tmp10 = tmp0 + tmp3; /* phase 2 */\r
+ tmp13 = tmp0 - tmp3;\r
+ tmp11 = tmp1 + tmp2;\r
+ tmp12 = tmp1 - tmp2;\r
+ \r
+ data[dataOff+ 0] = tmp10 + tmp11; /* phase 3 */\r
+ data[dataOff+32] = tmp10 - tmp11;\r
+ \r
+ z1 = (tmp12 + tmp13) * 0.707106781; /* c4 */\r
+ data[dataOff+16] = tmp13 + z1; /* phase 5 */\r
+ data[dataOff+48] = tmp13 - z1;\r
+ \r
+ /* Odd part */\r
+ tmp10 = tmp4 + tmp5; /* phase 2 */\r
+ tmp11 = tmp5 + tmp6;\r
+ tmp12 = tmp6 + tmp7;\r
+ \r
+ /* The rotator is modified from fig 4-8 to avoid extra negations. */\r
+ z5 = (tmp10 - tmp12) * 0.382683433; /* c6 */\r
+ z2 = 0.541196100 * tmp10 + z5; /* c2-c6 */\r
+ z4 = 1.306562965 * tmp12 + z5; /* c2+c6 */\r
+ z3 = tmp11 * 0.707106781; /* c4 */\r
+ \r
+ z11 = tmp7 + z3; /* phase 5 */\r
+ z13 = tmp7 - z3;\r
+ \r
+ data[dataOff+40] = z13 + z2; /* phase 6 */\r
+ data[dataOff+24] = z13 - z2;\r
+ data[dataOff+ 8] = z11 + z4;\r
+ data[dataOff+56] = z11 - z4;\r
+ \r
+ dataOff++; /* advance pointer to next column */\r
+ }\r
+ \r
+ // Quantize/descale the coefficients\r
+ for (i=0; i<64; i++) {\r
+ // Apply the quantization and scaling factor & Round to nearest integer\r
+ data[i] = Math.round((data[i]*fdtbl[i]));\r
+ }\r
+ return data;\r
+ }\r
+ \r
+ // Chunk writing\r
+ \r
+ private function writeAPP0():void\r
+ {\r
+ writeWord(0xFFE0); // marker\r
+ writeWord(16); // length\r
+ writeByte(0x4A); // J\r
+ writeByte(0x46); // F\r
+ writeByte(0x49); // I\r
+ writeByte(0x46); // F\r
+ writeByte(0); // = "JFIF",'\0'\r
+ writeByte(1); // versionhi\r
+ writeByte(1); // versionlo\r
+ writeByte(0); // xyunits\r
+ writeWord(1); // xdensity\r
+ writeWord(1); // ydensity\r
+ writeByte(0); // thumbnwidth\r
+ writeByte(0); // thumbnheight\r
+ }\r
+ \r
+ private function writeSOF0(width:int, height:int):void\r
+ {\r
+ writeWord(0xFFC0); // marker\r
+ writeWord(17); // length, truecolor YUV JPG\r
+ writeByte(8); // precision\r
+ writeWord(height);\r
+ writeWord(width);\r
+ writeByte(3); // nrofcomponents\r
+ writeByte(1); // IdY\r
+ writeByte(0x11); // HVY\r
+ writeByte(0); // QTY\r
+ writeByte(2); // IdU\r
+ writeByte(0x11); // HVU\r
+ writeByte(1); // QTU\r
+ writeByte(3); // IdV\r
+ writeByte(0x11); // HVV\r
+ writeByte(1); // QTV\r
+ }\r
+ \r
+ private function writeDQT():void\r
+ {\r
+ writeWord(0xFFDB); // marker\r
+ writeWord(132); // length\r
+ writeByte(0);\r
+ var i:int;\r
+ for (i=0; i<64; i++) {\r
+ writeByte(YTable[i]);\r
+ }\r
+ writeByte(1);\r
+ for (i=0; i<64; i++) {\r
+ writeByte(UVTable[i]);\r
+ }\r
+ }\r
+ \r
+ private function writeDHT():void\r
+ {\r
+ writeWord(0xFFC4); // marker\r
+ writeWord(0x01A2); // length\r
+ var i:int;\r
+ \r
+ writeByte(0); // HTYDCinfo\r
+ for (i=0; i<16; i++) {\r
+ writeByte(std_dc_luminance_nrcodes[i+1]);\r
+ }\r
+ for (i=0; i<=11; i++) {\r
+ writeByte(std_dc_luminance_values[i]);\r
+ }\r
+ \r
+ writeByte(0x10); // HTYACinfo\r
+ for (i=0; i<16; i++) {\r
+ writeByte(std_ac_luminance_nrcodes[i+1]);\r
+ }\r
+ for (i=0; i<=161; i++) {\r
+ writeByte(std_ac_luminance_values[i]);\r
+ }\r
+ \r
+ writeByte(1); // HTUDCinfo\r
+ for (i=0; i<16; i++) {\r
+ writeByte(std_dc_chrominance_nrcodes[i+1]);\r
+ }\r
+ for (i=0; i<=11; i++) {\r
+ writeByte(std_dc_chrominance_values[i]);\r
+ }\r
+ \r
+ writeByte(0x11); // HTUACinfo\r
+ for (i=0; i<16; i++) {\r
+ writeByte(std_ac_chrominance_nrcodes[i+1]);\r
+ }\r
+ for (i=0; i<=161; i++) {\r
+ writeByte(std_ac_chrominance_values[i]);\r
+ }\r
+ }\r
+ \r
+ private function writeSOS():void\r
+ {\r
+ writeWord(0xFFDA); // marker\r
+ writeWord(12); // length\r
+ writeByte(3); // nrofcomponents\r
+ writeByte(1); // IdY\r
+ writeByte(0); // HTY\r
+ writeByte(2); // IdU\r
+ writeByte(0x11); // HTU\r
+ writeByte(3); // IdV\r
+ writeByte(0x11); // HTV\r
+ writeByte(0); // Ss\r
+ writeByte(0x3f); // Se\r
+ writeByte(0); // Bf\r
+ }\r
+ \r
+ // Core processing\r
+ private var DU:Array = new Array(64);\r
+ \r
+ private function processDU(CDU:Array, fdtbl:Array, DC:Number, HTDC:Array, HTAC:Array):Number\r
+ {\r
+ var EOB:BitString = HTAC[0x00];\r
+ var M16zeroes:BitString = HTAC[0xF0];\r
+ var i:int;\r
+ \r
+ var DU_DCT:Array = fDCTQuant(CDU, fdtbl);\r
+ //ZigZag reorder\r
+ for (i=0;i<64;i++) {\r
+ DU[ZigZag[i]]=DU_DCT[i];\r
+ }\r
+ var Diff:int = DU[0] - DC; DC = DU[0];\r
+ //Encode DC\r
+ if (Diff==0) {\r
+ writeBits(HTDC[0]); // Diff might be 0\r
+ } else {\r
+ writeBits(HTDC[category[32767+Diff]]);\r
+ writeBits(bitcode[32767+Diff]);\r
+ }\r
+ //Encode ACs\r
+ var end0pos:int = 63;\r
+ for (; (end0pos>0)&&(DU[end0pos]==0); end0pos--) {\r
+ };\r
+ //end0pos = first element in reverse order !=0\r
+ if ( end0pos == 0) {\r
+ writeBits(EOB);\r
+ return DC;\r
+ }\r
+ i = 1;\r
+ while ( i <= end0pos ) {\r
+ var startpos:int = i;\r
+ for (; (DU[i]==0) && (i<=end0pos); i++) {\r
+ }\r
+ var nrzeroes:int = i-startpos;\r
+ if ( nrzeroes >= 16 ) {\r
+ for (var nrmarker:int=1; nrmarker <= nrzeroes/16; nrmarker++) {\r
+ writeBits(M16zeroes);\r
+ }\r
+ nrzeroes = int(nrzeroes&0xF);\r
+ }\r
+ writeBits(HTAC[nrzeroes*16+category[32767+DU[i]]]);\r
+ writeBits(bitcode[32767+DU[i]]);\r
+ i++;\r
+ }\r
+ if ( end0pos != 63 ) {\r
+ writeBits(EOB);\r
+ }\r
+ return DC;\r
+ }\r
+ \r
+ private var YDU:Array = new Array(64);\r
+ private var UDU:Array = new Array(64);\r
+ private var VDU:Array = new Array(64);\r
+ \r
+ private function RGB2YUV(img:BitmapData, xpos:int, ypos:int):void\r
+ {\r
+ var pos:int=0;\r
+ for (var y:int=0; y<8; y++) {\r
+ for (var x:int=0; x<8; x++) {\r
+ var P:uint = img.getPixel32(xpos+x,ypos+y);\r
+ var R:Number = Number((P>>16)&0xFF);\r
+ var G:Number = Number((P>> 8)&0xFF);\r
+ var B:Number = Number((P )&0xFF);\r
+ YDU[pos]=((( 0.29900)*R+( 0.58700)*G+( 0.11400)*B))-128;\r
+ UDU[pos]=(((-0.16874)*R+(-0.33126)*G+( 0.50000)*B));\r
+ VDU[pos]=((( 0.50000)*R+(-0.41869)*G+(-0.08131)*B));\r
+ pos++;\r
+ }\r
+ }\r
+ }\r
+ \r
+ /**\r
+ * Constructor for JPEGEncoder class\r
+ *\r
+ * @param quality The quality level between 1 and 100 that detrmines the\r
+ * level of compression used in the generated JPEG\r
+ * @langversion ActionScript 3.0\r
+ * @playerversion Flash 9.0\r
+ * @tiptext\r
+ */ \r
+ public function JPGEncoder(quality:Number = 50)\r
+ {\r
+ if (quality <= 0) {\r
+ quality = 1;\r
+ }\r
+ if (quality > 100) {\r
+ quality = 100;\r
+ }\r
+ var sf:int = 0;\r
+ if (quality < 50) {\r
+ sf = int(5000 / quality);\r
+ } else {\r
+ sf = int(200 - quality*2);\r
+ }\r
+ // Create tables\r
+ initHuffmanTbl();\r
+ initCategoryNumber();\r
+ initQuantTables(sf);\r
+ }\r
+ \r
+ /**\r
+ * Created a JPEG image from the specified BitmapData\r
+ *\r
+ * @param image The BitmapData that will be converted into the JPEG format.\r
+ * @return a ByteArray representing the JPEG encoded image data.\r
+ * @langversion ActionScript 3.0\r
+ * @playerversion Flash 9.0\r
+ * @tiptext\r
+ */ \r
+ public function encode(image:BitmapData):ByteArray\r
+ {\r
+ // Initialize bit writer\r
+ byteout = new ByteArray();\r
+ bytenew=0;\r
+ bytepos=7;\r
+ \r
+ // Add JPEG headers\r
+ writeWord(0xFFD8); // SOI\r
+ writeAPP0();\r
+ writeDQT();\r
+ writeSOF0(image.width,image.height);\r
+ writeDHT();\r
+ writeSOS();\r
+\r
+ \r
+ // Encode 8x8 macroblocks\r
+ var DCY:Number=0;\r
+ var DCU:Number=0;\r
+ var DCV:Number=0;\r
+ bytenew=0;\r
+ bytepos=7;\r
+ for (var ypos:int=0; ypos<image.height; ypos+=8) {\r
+ for (var xpos:int=0; xpos<image.width; xpos+=8) {\r
+ RGB2YUV(image, xpos, ypos);\r
+ DCY = processDU(YDU, fdtbl_Y, DCY, YDC_HT, YAC_HT);\r
+ DCU = processDU(UDU, fdtbl_UV, DCU, UVDC_HT, UVAC_HT);\r
+ DCV = processDU(VDU, fdtbl_UV, DCV, UVDC_HT, UVAC_HT);\r
+ }\r
+ }\r
+ \r
+ // Do the bit alignment of the EOI marker\r
+ if ( bytepos >= 0 ) {\r
+ var fillbits:BitString = new BitString();\r
+ fillbits.len = bytepos+1;\r
+ fillbits.val = (1<<(bytepos+1))-1;\r
+ writeBits(fillbits);\r
+ }\r
+ \r
+ writeWord(0xFFD9); //EOI\r
+ return byteout;\r
+ }\r
+ }\r
+}\r