hackedteam/rcs-console

// ==================================================================
// Module:        WinBmpFileHdr.as
//
// Description:    Windows Bitmap File Header class
//                 - represents first 14 bytes of the file, aka fileheader
//
// Author(s):    C.T. Yeung     (cty)
//
// History:
// 14Feb09        first completion of decoder                        cty
// 21Feb09        fully functional as Windows paint bmp format.
//                - no compression and no 16bpp.                    cty
//
// Copyright (c) 2009 C.T.Yeung

// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:

// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
// ==================================================================
package com.WindowsBitmap
{
    import flash.utils.ByteArray;
    
    public class WinBmpFileHdr
    {
        public static const SIZE:int = 14;
        public var bytes:ByteArray;
        
        public var ubfType1:String="B";        // 1 byte - File id "B" 
        public var ubfType2:String="M";        // 1 byte - File id "M"
        public var lbfSize:uint;            // 4 bytes - File length in bytes
        public var iRes1:int;                // 2 bytes - reserved 0
        public var iRes2:int;                // 2 bytes - reserved 0
        public var lbfOffs:uint;            // 4 bytes - offset from start of file to image data
        
        private var bmpHdr:WinBmpHdr;
        private var bmpPal:WinBmpPal;
        private var bmpImg:WinBmpImg;

/////////////////////////////////////////////////////////////////////
// Initialization
        
        public function WinBmpFileHdr()
        {
        }
        
        public function setRef(bmpHdr:WinBmpHdr,
                               bmpPal:WinBmpPal,
                               bmpImg:WinBmpImg):void
        {
            this.bmpHdr = bmpHdr;
            this.bmpPal = bmpPal;
            this.bmpImg = bmpImg;
        }
        
        public function empty():void
        {
            lbfSize = 0;
            lbfOffs = 0;    
        }
        
        public function isEmpty():Boolean
        {
            if (!bmpHdr||!bmpPal||!bmpImg)
                return true;
            return false;
        }
        
/////////////////////////////////////////////////////////////////////
// public 

        /**
         * Encode data to bmp file (work in progress)
         * @return 
         */
        public function encode():Boolean
        {
            if (!bmpHdr)    return false;
            if (!bmpPal)    return false;
            if (!bmpImg)    return false;
            
            lbfOffs =     WinBmpFileHdr.SIZE +
                        WinBmpHdr.SIZE +
                        WinBmpPal.paletteSize(bmpHdr.ibiBitCount);
            
            lbfSize = lbfOffs + bmpHdr.lbiSizeImage;
                        
            bytes = new ByteArray();
            bytes.writeMultiByte(ubfType1, "us-ascii");    
            bytes.writeMultiByte(ubfType2, "us-ascii");    
            bytes.writeByte((lbfSize & 0xFF))
            bytes.writeByte((lbfSize & 0xFF00)>>(8))
            bytes.writeByte((lbfSize & 0xFF0000)>>(8*2))
            bytes.writeByte((lbfSize & 0xFF000000)>>(8*3))
            bytes.writeByte(0);
            bytes.writeByte(0);
            bytes.writeByte(0);
            bytes.writeByte(0);
            bytes.writeByte((lbfOffs & 0xFF))
            bytes.writeByte((lbfOffs & 0xFF00)>>(8))
            bytes.writeByte((lbfOffs & 0xFF0000)>>(8*2))
            bytes.writeByte((lbfOffs & 0xFF000000)>>(8*3))
            return true;
        }
        
        /**
         * Decode bmp file's bitmap file header.
         * Validate file format.
         * @param bytes
         * @return true if successful, false upon failure
         */        
        public function decode    (bytes:ByteArray)    // bytes of the entire file
                                :Boolean            // success or not
        {
            if (bytes.length < SIZE) return false;
            if (bytes[0] != 66) return false;
            if (bytes[1] != 77) return false;
            
            // file size
            lbfSize =     uint(bytes[2]);
            lbfSize +=     uint(bytes[3]) << (8); 
            lbfSize +=     uint(bytes[4]) << (8*2);  
            lbfSize +=     uint(bytes[5]) << (8*3);
            if (lbfSize != bytes.length) return false;
            
            // image pixel offset
            lbfOffs =  uint(bytes[10]);
            lbfOffs += uint(bytes[11]) << (8);
            lbfOffs += uint(bytes[12]) << (8*2);
            lbfOffs += uint(bytes[13]) << (8*3);
            if ( lbfOffs < WinBmpFileHdr.SIZE+WinBmpHdr.SIZE) return false;
            return true;
        }

/////////////////////////////////////////////////////////////////////
// private 

        /**
         * Calculate lbiOffs
         * - image offset position from start of file
         * @return 
         */        
        protected function get imageOffset():int 
        {
            var palByteCount:int = WinBmpPal.paletteSize(bmpHdr.ibiBitCount);
            return palByteCount + WinBmpFileHdr.SIZE + WinBmpHdr.SIZE;
        }
    }
}