[亮度、对比度、饱和度的调整]

以下代码用ScanLine配合指针移动实现！

function Min(a, b: integer): integer;

begin

 if a < b then

  result := a

 else

  result := b;

end;

function Max(a, b: integer): integer;

begin

 if a > b then

  result := a

 else

  result := b;

end;

//亮度调整

procedure BrightnessChange(const SrcBmp,DestBmp:TBitmap;ValueChange:integer);

var

 i, j: integer;

 SrcRGB, DestRGB: pRGBTriple;

begin

 for i := 0 to SrcBmp.Height - 1 do

 begin

  SrcRGB := SrcBmp.ScanLine[i];

  DestRGB := DestBmp.ScanLine[i];

  for j := 0 to SrcBmp.Width - 1 do

  begin

   if ValueChange > 0 then

   begin

    DestRGB.rgbtRed := Min(255, SrcRGB.rgbtRed + ValueChange);

    DestRGB.rgbtGreen := Min(255, SrcRGB.rgbtGreen + ValueChange);

    DestRGB.rgbtBlue := Min(255, SrcRGB.rgbtBlue + ValueChange);

   end else begin

    DestRGB.rgbtRed := Max(0, SrcRGB.rgbtRed + ValueChange);

    DestRGB.rgbtGreen := Max(0, SrcRGB.rgbtGreen + ValueChange);

    DestRGB.rgbtBlue := Max(0, SrcRGB.rgbtBlue + ValueChange);

   end;

   Inc(SrcRGB);

   Inc(DestRGB);

  end;

 end;

end;

//对比度调整

procedure ContrastChange(const SrcBmp,DestBmp:TBitmap;ValueChange:integer);

var

 i, j: integer;

 SrcRow, DestRow: pRGBTriple;

begin

 for i := 0 to SrcBmp.Height - 1 do

 begin

  SrcRow := SrcBmp.ScanLine[i];

  DestRow := DestBmp.ScanLine[i];

  for j := 0 to SrcBmp.Width - 1 do

  begin

   if ValueChange>=0 then

   begin

   if SrcRow.rgbtRed >= 128 then

    DestRow.rgbtRed := Min(255, SrcRow.rgbtRed + (Abs(128 - SrcRow.rgbtRed) * ValueChange) div 128)

   else

    DestRow.rgbtRed := Max(0, SrcRow.rgbtRed - (Abs(128 - SrcRow.rgbtRed) * ValueChange) div 128);

   if SrcRow.rgbtGreen >= 128 then

    DestRow.rgbtGreen := Min(255, SrcRow.rgbtGreen + (Abs(128 - SrcRow.rgbtGreen) * ValueChange) div 128)

   else

    DestRow.rgbtGreen := Max(0, SrcRow.rgbtGreen - (Abs(128 - SrcRow.rgbtGreen) * ValueChange) div 128);

   if SrcRow.rgbtBlue >= 128 then

    DestRow.rgbtBlue := Min(255, SrcRow.rgbtBlue + (Abs(128 - SrcRow.rgbtBlue) * ValueChange) div 128)

   else

    DestRow.rgbtBlue := Max(0, SrcRow.rgbtBlue - (Abs(128 - SrcRow.rgbtBlue) * ValueChange) div 128);

   end

   else

   begin

   if SrcRow.rgbtRed >= 128 then

    DestRow.rgbtRed := Max(128, SrcRow.rgbtRed + (Abs(128 - SrcRow.rgbtRed) * ValueChange) div 128)

   else

    DestRow.rgbtRed := Min(128, SrcRow.rgbtRed - (Abs(128 - SrcRow.rgbtRed) * ValueChange) div 128);

   if SrcRow.rgbtGreen >= 128 then

    DestRow.rgbtGreen := Max(128, SrcRow.rgbtGreen + (Abs(128 - SrcRow.rgbtGreen) * ValueChange) div 128)

   else

    DestRow.rgbtGreen := Min(128, SrcRow.rgbtGreen - (Abs(128 - SrcRow.rgbtGreen) * ValueChange) div 128);

   if SrcRow.rgbtBlue >= 128 then

    DestRow.rgbtBlue := Max(128, SrcRow.rgbtBlue + (Abs(128 - SrcRow.rgbtBlue) * ValueChange) div 128)

   else

    DestRow.rgbtBlue := Min(128, SrcRow.rgbtBlue - (Abs(128 - SrcRow.rgbtBlue) * ValueChange) div 128);

   end;

   Inc(SrcRow);

   Inc(DestRow);

  end;

 end;

end;

//饱和度调整

procedure SaturationChange(const SrcBmp,DestBmp:TBitmap;ValueChange:integer);

var

 Grays: array[0..767] of Integer;

 Alpha: array[0..255] of Word;

 Gray, x, y: Integer;

 SrcRGB,DestRGB: pRGBTriple;

 i: Byte;

begin

ValueChange:=ValueChange+255;

for i := 0 to 255 do

 Alpha[i] := (i * ValueChange) Shr 8;

x := 0;

for i := 0 to 255 do

begin

 Gray := i - Alpha[i];

 Grays[x] := Gray;

 Inc(x);

 Grays[x] := Gray;

 Inc(x);

 Grays[x] := Gray;

 Inc(x);

end;

for y := 0 to SrcBmp.Height - 1 do

begin

 SrcRGB := SrcBmp.ScanLine[Y];

 DestRGB := DestBmp.ScanLine[Y];

 for x := 0 to SrcBmp.Width - 1 do

 begin

  Gray := Grays[SrcRGB.rgbtRed + SrcRGB.rgbtGreen + SrcRGB.rgbtBlue];

  if Gray + Alpha[SrcRGB.rgbtRed]>0 then

   DestRGB.rgbtRed := Min(255,Gray + Alpha[SrcRGB.rgbtRed])

  else

   DestRGB.rgbtRed := 0;

  if Gray + Alpha[SrcRGB.rgbtGreen]>0 then

   DestRGB.rgbtGreen := Min(255,Gray + Alpha[SrcRGB.rgbtGreen])

  else

   DestRGB.rgbtGreen := 0;

  if Gray + Alpha[SrcRGB.rgbtBlue]>0 then

   DestRGB.rgbtBlue := Min(255,Gray + Alpha[SrcRGB.rgbtBlue])

  else

   DestRGB.rgbtBlue := 0;

  Inc(SrcRGB);

  Inc(DestRGB);

 end;

end;

end;

//RGB调整

procedure RGBChange(SrcBmp,DestBmp:TBitmap;RedChange,GreenChange,BlueChange:integer);

var

 SrcRGB, DestRGB: pRGBTriple;

 i,j:integer;

begin

 for i := 0 to SrcBmp.Height- 1 do

 begin

  SrcRGB := SrcBmp.ScanLine[i];

  DestRGB :=DestBmp.ScanLine[i];

  for j := 0 to SrcBmp.Width - 1 do

  begin

   if RedChange> 0 then

    DestRGB.rgbtRed := Min(255, SrcRGB.rgbtRed + RedChange)

   else

    DestRGB.rgbtRed := Max(0, SrcRGB.rgbtRed + RedChange);

   if GreenChange> 0 then

    DestRGB.rgbtGreen := Min(255, SrcRGB.rgbtGreen + GreenChange)

   else

    DestRGB.rgbtGreen := Max(0, SrcRGB.rgbtGreen + GreenChange);

   if BlueChange> 0 then

    DestRGB.rgbtBlue := Min(255, SrcRGB.rgbtBlue + BlueChange)

   else

    DestRGB.rgbtBlue := Max(0, SrcRGB.rgbtBlue + BlueChange);

   Inc(SrcRGB);

   Inc(DestRGB);

  end;

 end;

end;

如果有些图像处理的基础，这些代码都比较好理解，主要是三原色的值不要超过(0-255)的范围，有些朋友没有注意这问题，当超过范围后，会出现些难看的“色斑”！

[颜色调整]

//RGB<=>BGR

procedure RGB2BGR(const Bitmap:TBitmap);

var

 X: Integer;

 Y: Integer;

 PRGB: pRGBTriple;

 Color: Byte;

begin

 for Y := 0 to (Bitmap.Height - 1) do

 begin

  for X := 0 to (Bitmap.Width - 1) do

  begin

   Color := PRGB^.rgbtRed;

   PRGB^.rgbtRed := PRGB^.rgbtBlue;

   PRGB^.rgbtBlue := Color;

   Inc(PRGB);

  end;

  end

 end;

end;

//灰度化(加权)

procedure Grayscale(const Bitmap:TBitmap);

var

 X: Integer;

 Y: Integer;

 PRGB: pRGBTriple;

 Gray: Byte;

begin

 for Y := 0 to (Bitmap.Height - 1) do

 begin

  PRGB := Bitmap.ScanLine[Y];

  for X := 0 to (Bitmap.Width - 1) do

  begin

   Gray := (77 * Red + 151 * Green + 28 * Blue) shr 8;

   PRGB^.rgbtRed:=Gray;

   PRGB^.rgbtGreen:=Gray;

   PRGB^.rgbtBlue:=Gray;

   Inc(PRGB);

  end;

 end;

end;

关于灰度化，我的另一篇文章中进行了详细的探讨！