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9fe7ee0b81
- BMP Reader enhanced to full Microsoft specs:
+ support for 15,16 bit bitmaps.
+ support for strange color masks at 16, 32 bpp
+ rle4 and rle8 decoding
+ top-down stored bitmaps.
+ Palette behaviour changed: use palette at 1,4,8 bits.
+ Support for OnProgress
- BMP Writer support:
+ BitsPerPixel property.
+ Writing at all color depths.
+ RLE8 and RLE4 compression.
- Functions to create standard palettes:
CreateBlackAndWhitePalette
CreateWebSafePalette
CreateGrayScalePalette
CreateVGAPalette
git-svn-id: trunk@987 -
125 lines
3.2 KiB
ObjectPascal
125 lines
3.2 KiB
ObjectPascal
{*****************************************************************************}
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{
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This file is part of the Free Pascal's "Free Components Library".
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Copyright (c) 2003 by Mazen NEIFER of the Free Pascal development team
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BMP reader/writer common code.
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See the file COPYING.FPC, included in this distribution,
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for details about the copyright.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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}
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{*****************************************************************************}
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{$mode objfpc}{$h+}
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unit BMPcomn;
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interface
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const
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{BMP magic word is always 19778 : 'BM'}
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BMmagic=19778;
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{ Values for Compression field }
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BI_RGB = 0;
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BI_RLE8 = 1;
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BI_RLE4 = 2;
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BI_BITFIELDS = 3;
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BI_JPEG = 4;
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BI_PNG = 5;
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type
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TBitMapFileHeader = packed record
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{00+02 :File type}
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bfType:word;
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{02+04 :File size in bytes}
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bfSize:longint;
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{06+04 : Reserved}
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bfReserved:longint;
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{10+04 : Offset of image data : size if the file hieder + the info header + palette}
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bfOffset:longint;
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end;
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PBitMapFileHeader = ^TBitMapFileHeader;
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TBitMapInfoHeader = packed record
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{14+04 : Size of the bitmap info header : sould be 40=$28}
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Size:longint;
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{18+04 : Image width in pixels}
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Width:longint;
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{22+04 : Image height in pixels}
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Height:longint;
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{26+02 : Number of image planes : should be 1 always}
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Planes:word;
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{28+02 : Color resolution : Number of bits per pixel (1,4,8,16,24,32)}
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BitCount:word;
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{30+04 : Compression Type}
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Compression:longint;
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{34+04 : Size of image data (not headers nor palette): can be 0 if no compression}
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SizeImage:longint;
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{38+04 : Horizontal resolution in pixel/meter}
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XPelsPerMeter:Longint;
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{42+04 : Vertical resolution in pixel/meter}
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YPelsPerMeter:Longint;
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{46+04 : Number of colors used}
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ClrUsed:longint;
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{50+04 : Number of imprtant colors used : usefull for displaying on VGA256}
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ClrImportant:longint;
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end;
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PBitMapInfoHeader = ^TBitMapInfoHeader;
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TColorRGB=packed record
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B,G,R:Byte;
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end;
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PColorRGB = ^TColorRGB;
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TColorRGBA=packed record
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case Boolean of
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False:(B,G,R,A:Byte);
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True:(RGB:TColorRGB);
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end;
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PColorRGBA = ^TColorRGBA;
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{54+?? : Color map : Lenght of color map is 4 bytes + the rest until the beginning of image data fixed in BFH.bfOffset}
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TColorMap=TColorRGBA;
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procedure SwapBMPFileHeader(var BFH : TBitMapFileHeader);
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procedure SwapBMPInfoHeader(var BFI : TBitMapInfoHeader);
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implementation
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uses FPImgCmn;
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procedure SwapBMPFileHeader(var BFH : TBitMapFileHeader);
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begin
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with BFH do
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begin
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bfType:=swap(bfType);
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bfSize:=swap(bfSize);
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bfReserved:=swap(bfReserved);
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bfOffset:=swap(bfOffset);
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end;
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end;
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procedure SwapBMPInfoHeader(var BFI : TBitMapInfoHeader);
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begin
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with BFI do
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begin
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Size:=swap(Size);
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Width:=swap(Width);
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Height:=swap(Height);
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Planes:=swap(Planes);
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BitCount:=swap(BitCount);
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Compression:=swap(Compression);
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SizeImage:=swap(SizeImage);
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XPelsPerMeter:=swap(XPelsPerMeter);
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YPelsPerMeter:=swap(YPelsPerMeter);
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ClrUsed:=swap(ClrUsed);
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ClrImportant:=swap(ClrImportant);
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end;
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end;
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end.
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