I
import
Unregistered / Unconfirmed
GUEST, unregistred user!
ehom (？！) Delphi中的基本图象处理代码～～～
[图像的旋转和翻转]
以下代码用ScanLine配合指针移动实现，用于24位色，至于其它色深的处理和有些代码为什么要这样写的问题可查看我的另一篇文章！
//旋转90度
procedure Rotate90(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOut
RGBTriple;
Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Height;
Bmp.Height := Bitmap.Width;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine;
Inc(rowOut,Height - j);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
//旋转180度
procedure Rotate180(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOutRGBTriple;
Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Width;
Bmp.Height := Bitmap.Height;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine[Height - j];
Inc(rowOut,Width - i);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
//旋转270度
procedure Rotate270(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOutRGBTriple;
Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Height;
Bmp.Height := Bitmap.Width;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine[Width - i];
Inc(rowOut,j);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
任意角度旋转就是将原图上的像素映射到新图上，以下代码为了好理解，并未进行充分优化！但速度上已经比较快了！我的另一篇文章中对优化问题进行了些简单说明，也就是尽量少用浮点运算！
前面为判断部分，如果是90,180,270这类特殊角度，将调用上面的代码，这样效率更高！
//任意角度
function RotateBitmap(Bitmap:TBitmap;Angle:Integer;BackColor:TColor):TBitmap;
var
i,j,iOriginal,jOriginal,CosPoint,SinPoint : integer;
RowOriginal,RowRotated : pRGBTriple;
SinTheta,CosTheta : Extended;
AngleAdd : integer;
begin
Result:=TBitmap.Create;
Result.PixelFormat := pf24bit;
Result.Canvas.Brush.Color:=BackColor;
Angle:=Angle Mod 360;
if Angle<0 then Angle:=360-Abs(Angle);
if Angle=0 then
Result.Assign(Bitmap)
else if Angle=90 then
begin
Result.Assign(Bitmap);
Rotate90(Result);//如果是旋转90度，直接调用上面的代码
end
else if (Angle>90) and (Angle<180) then
begin
AngleAdd:=90;
Angle:=Angle-AngleAdd;
end
else if Angle=180 then
begin
Result.Assign(Bitmap);
Rotate180(Result);//如果是旋转180度，直接调用上面的过程
end
else if (Angle>180) and (Angle<270) then
begin
AngleAdd:=180;
Angle:=Angle-AngleAdd;
end
else if Angle=270 then
begin
Result.Assign(Bitmap);
Rotate270(Result);//如果是旋转270度，直接调用上面的过程
end
else if (Angle>270) and (Angle<360) then
begin
AngleAdd:=270;
Angle:=Angle-AngleAdd;
end
else
AngleAdd:=0;
if (Angle>0) and (Angle<90) then
begin
SinCos((Angle + AngleAdd) * Pi / 180, SinTheta, CosTheta);
if (SinTheta * CosTheta) < 0 then
begin
Result.Width := Round(Abs(Bitmap.Width * CosTheta - Bitmap.Height * SinTheta));
Result.Height := Round(Abs(Bitmap.Width * SinTheta - Bitmap.Height * CosTheta));
end
else
begin
Result.Width := Round(Abs(Bitmap.Width * CosTheta + Bitmap.Height * SinTheta));
Result.Height := Round(Abs(Bitmap.Width * SinTheta + Bitmap.Height * CosTheta));
end;
CosTheta:=Abs(CosTheta);
SinTheta:=Abs(SinTheta);
if (AngleAdd=0) or (AngleAdd=180) then
begin
CosPoint:=Round(Bitmap.Height*CosTheta);
SinPoint:=Round(Bitmap.Height*SinTheta);
end
else
begin
SinPoint:=Round(Bitmap.Width*CosTheta);
CosPoint:=Round(Bitmap.Width*SinTheta);
end;
for j := 0 to Result.Height-1 do
begin
RowRotated := Result.Scanline[j];
for i := 0 to Result.Width-1 do
begin
Case AngleAdd of
0:
begin
jOriginal := Round((j+1)*CosTheta-(i+1-SinPoint)*SinTheta)-1;
iOriginal := Round((i+1)*CosTheta-(CosPoint-j-1)*SinTheta)-1;
end;
90:
begin
iOriginal := Round((j+1)*SinTheta-(i+1-SinPoint)*CosTheta)-1;
jOriginal := Bitmap.Height-Round((i+1)*SinTheta-(CosPoint-j-1)*CosTheta);
end;
180:
begin
jOriginal := Bitmap.Height-Round((j+1)*CosTheta-(i+1-SinPoint)*SinTheta);
iOriginal := Bitmap.Width-Round((i+1)*CosTheta-(CosPoint-j-1)*SinTheta);
end;
270:
begin
iOriginal := Bitmap.Width-Round((j+1)*SinTheta-(i+1-SinPoint)*CosTheta);
jOriginal := Round((i+1)*SinTheta-(CosPoint-j-1)*CosTheta)-1;
end;
end;
if (iOriginal >= 0) and (iOriginal <= Bitmap.Width-1)and
(jOriginal >= 0) and (jOriginal <= Bitmap.Height-1)
then
begin
RowOriginal := Bitmap.Scanline[jOriginal];
Inc(RowOriginal,iOriginal);
RowRotated^ := RowOriginal^;
Inc(RowRotated);
end
else
begin
Inc(RowRotated);
end;
end;
end;
end;
end;
虽然这已经实现了图像任意角度的旋转，但注意看看上面的代码，都是用Round取整，也就是在原图中找最近的像素填充到新图中，这样在边缘会产生锯齿！如果想效果更好，应该是用四个像素的值运算后得到新像素的值！
如对应到原图的坐标是(6.3,8.6)，用第一种方法可能就用(6,9)填充了该像素，但如果想消除边缘锯齿，就应该用(6,8)、(6,9)、(7,8)、(7,9)运算得出新点的像素，而边缘就用颜色等于背景色的点代替！
感兴趣的朋友可以找些二次线性插值资料看看，或者以后再讨论，这里就不多说了！
后面的浮雕滤镜效果其实就用到了线性插值的思想！
//水平翻转
procedure FlipHorz(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOutRGBTriple;
Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Width;
Bmp.Height := Bitmap.Height;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine[j];
Inc(rowOut,Width - i);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
//垂直翻转
procedure FlipVert(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOutRGBTriple;
Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Height;
Bmp.Height := Bitmap.Width;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine[Height - j];
Inc(rowOut,i);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
其实旋转90、180、270度，水平垂直翻转的原理基本类似，所以也可以改写为一个过程！
如果灵活的使用指针，减少用ScanLine的次数，代码效率还能有所提升～～～
[亮度、对比度、饱和度的调整]
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;
DestRGB := DestBmp.ScanLine;
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;
SrcRGB, DestRGB: pRGBTriple;
begin
for i := 0 to SrcBmp.Height - 1 do
begin
SrcRGB := SrcBmp.ScanLine;
DestRGB := DestBmp.ScanLine;
for j := 0 to SrcBmp.Width - 1 do
begin
if ValueChange>=0 then
begin
if SrcRGB.rgbtRed >= 128 then
DestRGB.rgbtRed := Min(255, SrcRGB.rgbtRed + ValueChange)
else
DestRGB.rgbtRed := Max(0, SrcRGB.rgbtRed - ValueChange);
if SrcRGB.rgbtGreen >= 128 then
DestRGB.rgbtGreen := Min(255, SrcRGB.rgbtGreen + ValueChange)
else
DestRGB.rgbtGreen := Max(0, SrcRGB.rgbtGreen - ValueChange);
if SrcRGB.rgbtBlue >= 128 then
DestRGB.rgbtBlue := Min(255, SrcRGB.rgbtBlue + ValueChange)
else
DestRGB.rgbtBlue := Max(0, SrcRGB.rgbtBlue - ValueChange);
end
else
begin
if SrcRGB.rgbtRed >= 128 then
DestRGB.rgbtRed := Max(128, SrcRGB.rgbtRed + ValueChange)
else
DestRGB.rgbtRed := Min(128, SrcRGB.rgbtRed - ValueChange);
if SrcRGB.rgbtGreen >= 128 then
DestRGB.rgbtGreen := Max(128, SrcRGB.rgbtGreen + ValueChange)
else
DestRGB.rgbtGreen := Min(128, SrcRGB.rgbtGreen - ValueChange);
if SrcRGB.rgbtBlue >= 128 then
DestRGB.rgbtBlue := Max(128, SrcRGB.rgbtBlue + ValueChange)
else
DestRGB.rgbtBlue := Min(128, SrcRGB.rgbtBlue - ValueChange);
end;
Inc(SrcRGB);
Inc(DestRGB);
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 * ValueChange) Shr 8;
x := 0;
for i := 0 to 255 do
begin
Gray := i - Alpha;
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;
DestRGB :=DestBmp.ScanLine;
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！
[常用滤镜效果]
过于浮雕效果，代码网上也有，但一般不支持角度变化！这里根据角度的不同，在一个像素周围的8个像素中取不同的两个运算得到新颜色值，用这个值和它求差值实现浮雕效果。用到了线性插值的思想。这里没有使用浮点运算！
//浮雕
procedure Emboss(SrcBmp,DestBmp:TBitmap;AzimuthChange:integer);overload;
var
i, j, Gray, Azimuthvalue, R, G, B: integer;
SrcRGB, SrcRGB1, SrcRGB2, DestRGB: pRGBTriple;
begin
for i := 0 to SrcBmp.Height - 1 do
begin
SrcRGB := SrcBmp.ScanLine;
DestRGB := DestBmp.ScanLine;
if (AzimuthChange >= -180) and (AzimuthChange < -135) then
begin
if i > 0 then
SrcRGB1 := SrcBmp.ScanLine[i-1]
else
SrcRGB1 := SrcRGB;
Inc(SrcRGB1);
SrcRGB2 := SrcRGB;
Inc(SrcRGB2);
end
else if (AzimuthChange >= -135) and (AzimuthChange < -90) then
begin
if i > 0 then
SrcRGB1 := SrcBmp.ScanLine[i-1]
else
SrcRGB1 := SrcRGB;
SrcRGB2 := SrcRGB1;
Inc(SrcRGB2);
end
else if (AzimuthChange >= -90) and (AzimuthChange < -45) then
begin
if i > 0 then
SrcRGB1 := SrcBmp.ScanLine[i-1]
else
SrcRGB1 := SrcRGB;
SrcRGB2 := SrcRGB1;
end
else if (AzimuthChange >= -45) and (AzimuthChange < 0) then
begin
SrcRGB1 := SrcRGB;
if i > 0 then
SrcRGB2 := SrcBmp.ScanLine[i-1]
else
SrcRGB2 := SrcRGB;
end
else if (AzimuthChange >= 0) and (AzimuthChange < 45) then
begin
SrcRGB2 := SrcRGB;
if (i < SrcBmp.Height - 1) then
SrcRGB1 := SrcBmp.ScanLine[i+1]
else
SrcRGB1 := SrcRGB;
end
else if (AzimuthChange >= 45) and (AzimuthChange < 90) then
begin
if (i < SrcBmp.Height - 1) then
SrcRGB1 := SrcBmp.ScanLine[i+1]
else
SrcRGB1 := SrcRGB;
SrcRGB2 := SrcRGB1;
end
else if (AzimuthChange >= 90) and (AzimuthChange < 135) then
begin
if (i < SrcBmp.Height - 1) then
SrcRGB1 := SrcBmp.ScanLine[i+1]
else
SrcRGB1 := SrcRGB;
SrcRGB2 := SrcRGB1;
Inc(SrcRGB1);
end
else if (AzimuthChange >= 135) and (AzimuthChange <= 180) then
begin
if (i < SrcBmp.Height - 1) then
SrcRGB2 := SrcBmp.ScanLine[i+1]
else
SrcRGB2 := SrcRGB;
Inc(SrcRGB2);
SrcRGB1 := SrcRGB;
Inc(SrcRGB1);
end;
for j := 0 to SrcBmp.Width - 1 do
begin
if (AzimuthChange >= -180) and (AzimuthChange < -135) then
begin
Azimuthvalue := AzimuthChange + 180;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= -135) and (AzimuthChange < -90) then
begin
Azimuthvalue := AzimuthChange + 135;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= -90) and (AzimuthChange < -45) then
begin
if j=1 then Inc(SrcRGB1,-1);
Azimuthvalue := AzimuthChange + 90;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= -45) and (AzimuthChange < 0) then
begin
if j=1 then
begin
Inc(SrcRGB1,-1);
Inc(SrcRGB2,-1);
end;
Azimuthvalue := AzimuthChange + 45;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= 0) and (AzimuthChange < 45) then
begin
if j=1 then
begin
Inc(SrcRGB1,-1);
Inc(SrcRGB2,-1);
end;
Azimuthvalue := AzimuthChange;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= 45) and (AzimuthChange < 90) then
begin
if j=1 then Inc(SrcRGB2,-1);
Azimuthvalue := AzimuthChange - 45;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= 90) and (AzimuthChange < 135) then
begin
Azimuthvalue := AzimuthChange - 90;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= 135) and (AzimuthChange <= 180) then
begin
Azimuthvalue := AzimuthChange - 135;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end;
R:=Min(R,255);
R:=Max(R,0);
G:=Min(G,255);
G:=Max(G,0);
B:=Min(B,255);
B:=Max(B,0);
Gray := (R shr 2) + (R shr 4) + (G shr 1) + (G shr 4) + (B shr 3);
DestRGB.rgbtRed:=Gray;
DestRGB.rgbtGreen:=Gray;
DestRGB.rgbtBlue:=Gray;
if (j<SrcBmp.Width - 1) or not (((AzimuthChange>=-180) and (AzimuthChange<-135)) or ((AzimuthChange>=90) and (AzimuthChange<=180))) then
begin
Inc(SrcRGB1);
end;
if (j<SrcBmp.Width - 1) or not (((AzimuthChange>=135) and (AzimuthChange<180)) or ((AzimuthChange>=-180) and (AzimuthChange<=-90))) then
begin
Inc(SrcRGB2);
end;
Inc(SrcRGB);
Inc(DestRGB);
end;
end;
end;
procedure Emboss(Bmp:TBitmap;AzimuthChange:integer;ElevationChange:integer;WeightChange:integer);overload;
var
DestBmp:TBitmap;
begin
DestBmp:=TBitmap.Create;
DestBmp.Assign(Bmp);
Emboss(Bmp,DestBmp,AzimuthChange,ElevationChange,WeightChange);
Bmp.Assign(DestBmp);
end;
//反色
procedure Negative(Bmp:TBitmap);
var
i, j: Integer;
PRGB: pRGBTriple;
begin
Bmp.PixelFormat:=pf24Bit;
for i := 0 to Bmp.Height - 1 do
begin
PRGB := Bmp.ScanLine;
for j := 0 to Bmp.Width - 1 do
begin
PRGB^.rgbtRed :=not PRGB^.rgbtRed
PRGB^.rgbtGreen :=not PRGB^.rgbtGreen;
PRGB^.rgbtBlue :=not PRGB^.rgbtBlue;
Inc(PRGB);
end;
end;
end;
//曝光
procedure Exposure(Bmp:TBitmap);
var
i, j: integer;
PRGB: pRGBTriple;
begin
Bmp.PixelFormat:=pf24Bit;
for i := 0 to Bmp.Height - 1 do
begin
PRGB := Bmp.ScanLine;
for j := 0 to Bmp.Width - 1 do
begin
if PRGB^.rgbtRed<128 then
PRGB^.rgbtRed :=not PRGB^.rgbtRed
if PRGB^.rgbtGreen<128 then
PRGB^.rgbtGreen :=not PRGB^.rgbtGreen;
if PRGB^.rgbtBlue<128 then
PRGB^.rgbtBlue :=not PRGB^.rgbtBlue;
Inc(PRGB);
end;
end;
end;
//模糊
procedure Blur(SrcBmp:TBitmap);
var
i, j:Integer;
SrcRGBRGBTriple;
SrcNextRGBRGBTriple;
SrcPreRGBRGBTriple;
Value:Integer;
procedure IncRGB;
begin
Inc(SrcPreRGB);
Inc(SrcRGB);
Inc(SrcNextRGB);
end;
procedure DecRGB;
begin
Inc(SrcPreRGB,-1);
Inc(SrcRGB,-1);
Inc(SrcNextRGB,-1);
end;
begin
SrcBmp.PixelFormat:=pf24Bit;
for i := 0 to SrcBmp.Height - 1 do
begin
if i > 0 then
SrcPreRGB:=SrcBmp.ScanLine[i-1]
else
SrcPreRGB := SrcBmp.ScanLine;
SrcRGB := SrcBmp.ScanLine;
if i < SrcBmp.Height - 1 then
SrcNextRGB:=SrcBmp.ScanLine[i+1]
else
SrcNextRGB:=SrcBmp.ScanLine;
for j := 0 to SrcBmp.Width - 1 do
begin
if j > 0 then DecRGB;
Value:=SrcPreRGB.rgbtRed+SrcRGB.rgbtRed+SrcNextRGB.rgbtRed;
if j > 0 then IncRGB;
Value:=Value+SrcPreRGB.rgbtRed+SrcRGB.rgbtRed+SrcNextRGB.rgbtRed;
if j < SrcBmp.Width - 1 then IncRGB;
Value:=(Value+SrcPreRGB.rgbtRed+SrcRGB.rgbtRed+SrcNextRGB.rgbtRed) div 9;
DecRGB;
SrcRGB.rgbtRed:=value;
if j > 0 then DecRGB;
Value:=SrcPreRGB.rgbtGreen+SrcRGB.rgbtGreen+SrcNextRGB.rgbtGreen;
if j > 0 then IncRGB;
Value:=Value+SrcPreRGB.rgbtGreen+SrcRGB.rgbtGreen+SrcNextRGB.rgbtGreen;
if j < SrcBmp.Width - 1 then IncRGB;
Value:=(Value+SrcPreRGB.rgbtGreen+SrcRGB.rgbtGreen+SrcNextRGB.rgbtGreen) div 9;
DecRGB;
SrcRGB.rgbtGreen:=value;
if j > 0 then DecRGB;
Value:=SrcPreRGB.rgbtBlue+SrcRGB.rgbtBlue+SrcNextRGB.rgbtBlue;
if j > 0 then IncRGB;
Value:=Value+SrcPreRGB.rgbtBlue+SrcRGB.rgbtBlue+SrcNextRGB.rgbtBlue;
if j < SrcBmp.Width - 1 then IncRGB;
Value:=(Value+SrcPreRGB.rgbtBlue+SrcRGB.rgbtBlue+SrcNextRGB.rgbtBlue) div 9;
DecRGB;
SrcRGB.rgbtBlue:=value;
IncRGB;
end;
end;
end;
//锐化
procedure Sharpen(SrcBmp:TBitmap);
var
i, j: integer;
SrcRGB: pRGBTriple;
SrcPreRGB: pRGBTriple;
Value: integer;
begin
SrcBmp.PixelFormat:=pf24Bit;
for i := 0 to SrcBmp.Height - 1 do
begin
SrcRGB := SrcBmp.ScanLine;
if i > 0 then
SrcPreRGB:=SrcBmp.ScanLine[i-1]
else
SrcPreRGB:=SrcBmp.ScanLine;
for j := 0 to SrcBmp.Width - 1 do
begin
if j = 1 then Dec(SrcPreRGB);
Value:=SrcRGB.rgbtRed+(SrcRGB.rgbtRed-SrcPreRGB.rgbtRed) div 2;
Value:=Max(0,Value);
Value:=Min(255,Value);
SrcRGB.rgbtRed:=value;
Value:=SrcRGB.rgbtGreen+(SrcRGB.rgbtGreen-SrcPreRGB.rgbtGreen) div 2;
Value:=Max(0,Value);
Value:=Min(255,Value);
SrcRGB.rgbtGreen:=value;
Value:=SrcRGB.rgbtBlue+(SrcRGB.rgbtBlue-SrcPreRGB.rgbtBlue) div 2;
Value:=Max(0,Value);
Value:=Min(255,Value);
SrcRGB.rgbtBlue:=value;
Inc(SrcRGB);
Inc(SrcPreRGB);
end;
end;
end;
由Delphi中的图像灰度化代码看基本图像处理～～～
http://expert.csdn.net/Expert/TopicView1.asp?id=1472467
模糊效果在处理指针移动时有些BUG,现贴出修正后的代码
//模糊
procedure Blur(SrcBmp:TBitmap);
var
i, j:Integer;
SrcRowRGBTriple;
SrcNextRowRGBTriple;
SrcPreRowRGBTriple;
Value:Integer;
procedure IncRow;
begin
Inc(SrcPreRow);
Inc(SrcRow);
Inc(SrcNextRow);
end;
procedure DecRow;
begin
Inc(SrcPreRow,-1);
Inc(SrcRow,-1);
Inc(SrcNextRow,-1);
end;
begin
SrcBmp.PixelFormat:=pf24Bit;
for i := 0 to SrcBmp.Height - 1 do
begin
if i > 0 then
SrcPreRow:=SrcBmp.ScanLine[i-1]
else
SrcPreRow := SrcBmp.ScanLine;
SrcRow := SrcBmp.ScanLine;
if i < SrcBmp.Height - 1 then
SrcNextRow:=SrcBmp.ScanLine[i+1]
else
SrcNextRow:=SrcBmp.ScanLine;
for j := 0 to SrcBmp.Width - 1 do
begin
if j > 0 then DecRow;
Value:=SrcPreRow.rgbtRed+SrcRow.rgbtRed+SrcNextRow.rgbtRed;
if j > 0 then IncRow;
Value:=Value+SrcPreRow.rgbtRed+SrcRow.rgbtRed+SrcNextRow.rgbtRed;
if j < SrcBmp.Width - 1 then IncRow;
Value:=(Value+SrcPreRow.rgbtRed+SrcRow.rgbtRed+SrcNextRow.rgbtRed) div 9;
if j < SrcBmp.Width - 1 then DecRow;
SrcRow.rgbtRed:=value;
if j > 0 then DecRow;
Value:=SrcPreRow.rgbtGreen+SrcRow.rgbtGreen+SrcNextRow.rgbtGreen;
if j > 0 then IncRow;
Value:=Value+SrcPreRow.rgbtGreen+SrcRow.rgbtGreen+SrcNextRow.rgbtGreen;
if j < SrcBmp.Width - 1 then IncRow;
Value:=(Value+SrcPreRow.rgbtGreen+SrcRow.rgbtGreen+SrcNextRow.rgbtGreen) div 9;
if j < SrcBmp.Width - 1 then DecRow;
SrcRow.rgbtGreen:=value;
if j > 0 then DecRow;
Value:=SrcPreRow.rgbtBlue+SrcRow.rgbtBlue+SrcNextRow.rgbtBlue;
if j > 0 then IncRow;
Value:=Value+SrcPreRow.rgbtBlue+SrcRow.rgbtBlue+SrcNextRow.rgbtBlue;
if j < SrcBmp.Width - 1 then IncRow;
Value:=(Value+SrcPreRow.rgbtBlue+SrcRow.rgbtBlue+SrcNextRow.rgbtBlue) div 9;
if j < SrcBmp.Width - 1 then DecRow;
SrcRow.rgbtBlue:=value;
IncRow;
end;
end;
end;
Windows provide two API "GetDeviceGammaRamp/SetDeviceGammaRamp" to perform gamma correction. In fact we need to have an 3 dimension buffer of 256 WORD to manipulate gamma correction. To change gamma it is necessary to change the RGB value of each color contained in the buffer by a float factor between 0.0 and 2.0.
上面的是系统支持的两个API（2000）
http://www.codeproject.com/useritems/gamma_manager.asp
回复人： ehom(？！) ( ) 信誉：128 2003-03-04 19:41:00 得分:0
//修改后的对比度调整代码
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;
DestRow := DestBmp.ScanLine;
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;
Top
[图像的旋转和翻转]
以下代码用ScanLine配合指针移动实现，用于24位色，至于其它色深的处理和有些代码为什么要这样写的问题可查看我的另一篇文章！
//旋转90度
procedure Rotate90(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOut
RGBTriple;Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Height;
Bmp.Height := Bitmap.Width;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine;
Inc(rowOut,Height - j);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
//旋转180度
procedure Rotate180(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOut
RGBTriple;Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Width;
Bmp.Height := Bitmap.Height;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine[Height - j];
Inc(rowOut,Width - i);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
//旋转270度
procedure Rotate270(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOut
RGBTriple;Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Height;
Bmp.Height := Bitmap.Width;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine[Width - i];
Inc(rowOut,j);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
任意角度旋转就是将原图上的像素映射到新图上，以下代码为了好理解，并未进行充分优化！但速度上已经比较快了！我的另一篇文章中对优化问题进行了些简单说明，也就是尽量少用浮点运算！
前面为判断部分，如果是90,180,270这类特殊角度，将调用上面的代码，这样效率更高！
//任意角度
function RotateBitmap(Bitmap:TBitmap;Angle:Integer;BackColor:TColor):TBitmap;
var
i,j,iOriginal,jOriginal,CosPoint,SinPoint : integer;
RowOriginal,RowRotated : pRGBTriple;
SinTheta,CosTheta : Extended;
AngleAdd : integer;
begin
Result:=TBitmap.Create;
Result.PixelFormat := pf24bit;
Result.Canvas.Brush.Color:=BackColor;
Angle:=Angle Mod 360;
if Angle<0 then Angle:=360-Abs(Angle);
if Angle=0 then
Result.Assign(Bitmap)
else if Angle=90 then
begin
Result.Assign(Bitmap);
Rotate90(Result);//如果是旋转90度，直接调用上面的代码
end
else if (Angle>90) and (Angle<180) then
begin
AngleAdd:=90;
Angle:=Angle-AngleAdd;
end
else if Angle=180 then
begin
Result.Assign(Bitmap);
Rotate180(Result);//如果是旋转180度，直接调用上面的过程
end
else if (Angle>180) and (Angle<270) then
begin
AngleAdd:=180;
Angle:=Angle-AngleAdd;
end
else if Angle=270 then
begin
Result.Assign(Bitmap);
Rotate270(Result);//如果是旋转270度，直接调用上面的过程
end
else if (Angle>270) and (Angle<360) then
begin
AngleAdd:=270;
Angle:=Angle-AngleAdd;
end
else
AngleAdd:=0;
if (Angle>0) and (Angle<90) then
begin
SinCos((Angle + AngleAdd) * Pi / 180, SinTheta, CosTheta);
if (SinTheta * CosTheta) < 0 then
begin
Result.Width := Round(Abs(Bitmap.Width * CosTheta - Bitmap.Height * SinTheta));
Result.Height := Round(Abs(Bitmap.Width * SinTheta - Bitmap.Height * CosTheta));
end
else
begin
Result.Width := Round(Abs(Bitmap.Width * CosTheta + Bitmap.Height * SinTheta));
Result.Height := Round(Abs(Bitmap.Width * SinTheta + Bitmap.Height * CosTheta));
end;
CosTheta:=Abs(CosTheta);
SinTheta:=Abs(SinTheta);
if (AngleAdd=0) or (AngleAdd=180) then
begin
CosPoint:=Round(Bitmap.Height*CosTheta);
SinPoint:=Round(Bitmap.Height*SinTheta);
end
else
begin
SinPoint:=Round(Bitmap.Width*CosTheta);
CosPoint:=Round(Bitmap.Width*SinTheta);
end;
for j := 0 to Result.Height-1 do
begin
RowRotated := Result.Scanline[j];
for i := 0 to Result.Width-1 do
begin
Case AngleAdd of
0:
begin
jOriginal := Round((j+1)*CosTheta-(i+1-SinPoint)*SinTheta)-1;
iOriginal := Round((i+1)*CosTheta-(CosPoint-j-1)*SinTheta)-1;
end;
90:
begin
iOriginal := Round((j+1)*SinTheta-(i+1-SinPoint)*CosTheta)-1;
jOriginal := Bitmap.Height-Round((i+1)*SinTheta-(CosPoint-j-1)*CosTheta);
end;
180:
begin
jOriginal := Bitmap.Height-Round((j+1)*CosTheta-(i+1-SinPoint)*SinTheta);
iOriginal := Bitmap.Width-Round((i+1)*CosTheta-(CosPoint-j-1)*SinTheta);
end;
270:
begin
iOriginal := Bitmap.Width-Round((j+1)*SinTheta-(i+1-SinPoint)*CosTheta);
jOriginal := Round((i+1)*SinTheta-(CosPoint-j-1)*CosTheta)-1;
end;
end;
if (iOriginal >= 0) and (iOriginal <= Bitmap.Width-1)and
(jOriginal >= 0) and (jOriginal <= Bitmap.Height-1)
then
begin
RowOriginal := Bitmap.Scanline[jOriginal];
Inc(RowOriginal,iOriginal);
RowRotated^ := RowOriginal^;
Inc(RowRotated);
end
else
begin
Inc(RowRotated);
end;
end;
end;
end;
end;
虽然这已经实现了图像任意角度的旋转，但注意看看上面的代码，都是用Round取整，也就是在原图中找最近的像素填充到新图中，这样在边缘会产生锯齿！如果想效果更好，应该是用四个像素的值运算后得到新像素的值！
如对应到原图的坐标是(6.3,8.6)，用第一种方法可能就用(6,9)填充了该像素，但如果想消除边缘锯齿，就应该用(6,8)、(6,9)、(7,8)、(7,9)运算得出新点的像素，而边缘就用颜色等于背景色的点代替！
感兴趣的朋友可以找些二次线性插值资料看看，或者以后再讨论，这里就不多说了！
后面的浮雕滤镜效果其实就用到了线性插值的思想！
//水平翻转
procedure FlipHorz(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOut
RGBTriple;Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Width;
Bmp.Height := Bitmap.Height;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine[j];
Inc(rowOut,Width - i);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
//垂直翻转
procedure FlipVert(const Bitmap:TBitmap);
var
i,j:Integer;
rowIn,rowOut
RGBTriple;Bmp:TBitmap;
Width,Height:Integer;
begin
Bmp:=TBitmap.Create;
Bmp.Width := Bitmap.Height;
Bmp.Height := Bitmap.Width;
Bmp.PixelFormat := pf24bit;
Width:=Bitmap.Width-1;
Height:=Bitmap.Height-1;
for j := 0 to Height do
begin
rowIn := Bitmap.ScanLine[j];
for i := 0 to Width do
begin
rowOut := Bmp.ScanLine[Height - j];
Inc(rowOut,i);
rowOut^ := rowIn^;
Inc(rowIn);
end;
end;
Bitmap.Assign(Bmp);
end;
其实旋转90、180、270度，水平垂直翻转的原理基本类似，所以也可以改写为一个过程！
如果灵活的使用指针，减少用ScanLine的次数，代码效率还能有所提升～～～
[亮度、对比度、饱和度的调整]
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;
DestRGB := DestBmp.ScanLine;
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;
SrcRGB, DestRGB: pRGBTriple;
begin
for i := 0 to SrcBmp.Height - 1 do
begin
SrcRGB := SrcBmp.ScanLine;
DestRGB := DestBmp.ScanLine;
for j := 0 to SrcBmp.Width - 1 do
begin
if ValueChange>=0 then
begin
if SrcRGB.rgbtRed >= 128 then
DestRGB.rgbtRed := Min(255, SrcRGB.rgbtRed + ValueChange)
else
DestRGB.rgbtRed := Max(0, SrcRGB.rgbtRed - ValueChange);
if SrcRGB.rgbtGreen >= 128 then
DestRGB.rgbtGreen := Min(255, SrcRGB.rgbtGreen + ValueChange)
else
DestRGB.rgbtGreen := Max(0, SrcRGB.rgbtGreen - ValueChange);
if SrcRGB.rgbtBlue >= 128 then
DestRGB.rgbtBlue := Min(255, SrcRGB.rgbtBlue + ValueChange)
else
DestRGB.rgbtBlue := Max(0, SrcRGB.rgbtBlue - ValueChange);
end
else
begin
if SrcRGB.rgbtRed >= 128 then
DestRGB.rgbtRed := Max(128, SrcRGB.rgbtRed + ValueChange)
else
DestRGB.rgbtRed := Min(128, SrcRGB.rgbtRed - ValueChange);
if SrcRGB.rgbtGreen >= 128 then
DestRGB.rgbtGreen := Max(128, SrcRGB.rgbtGreen + ValueChange)
else
DestRGB.rgbtGreen := Min(128, SrcRGB.rgbtGreen - ValueChange);
if SrcRGB.rgbtBlue >= 128 then
DestRGB.rgbtBlue := Max(128, SrcRGB.rgbtBlue + ValueChange)
else
DestRGB.rgbtBlue := Min(128, SrcRGB.rgbtBlue - ValueChange);
end;
Inc(SrcRGB);
Inc(DestRGB);
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 * ValueChange) Shr 8;
x := 0;
for i := 0 to 255 do
begin
Gray := i - Alpha;
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;
DestRGB :=DestBmp.ScanLine;
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！
[常用滤镜效果]
过于浮雕效果，代码网上也有，但一般不支持角度变化！这里根据角度的不同，在一个像素周围的8个像素中取不同的两个运算得到新颜色值，用这个值和它求差值实现浮雕效果。用到了线性插值的思想。这里没有使用浮点运算！
//浮雕
procedure Emboss(SrcBmp,DestBmp:TBitmap;AzimuthChange:integer);overload;
var
i, j, Gray, Azimuthvalue, R, G, B: integer;
SrcRGB, SrcRGB1, SrcRGB2, DestRGB: pRGBTriple;
begin
for i := 0 to SrcBmp.Height - 1 do
begin
SrcRGB := SrcBmp.ScanLine;
DestRGB := DestBmp.ScanLine;
if (AzimuthChange >= -180) and (AzimuthChange < -135) then
begin
if i > 0 then
SrcRGB1 := SrcBmp.ScanLine[i-1]
else
SrcRGB1 := SrcRGB;
Inc(SrcRGB1);
SrcRGB2 := SrcRGB;
Inc(SrcRGB2);
end
else if (AzimuthChange >= -135) and (AzimuthChange < -90) then
begin
if i > 0 then
SrcRGB1 := SrcBmp.ScanLine[i-1]
else
SrcRGB1 := SrcRGB;
SrcRGB2 := SrcRGB1;
Inc(SrcRGB2);
end
else if (AzimuthChange >= -90) and (AzimuthChange < -45) then
begin
if i > 0 then
SrcRGB1 := SrcBmp.ScanLine[i-1]
else
SrcRGB1 := SrcRGB;
SrcRGB2 := SrcRGB1;
end
else if (AzimuthChange >= -45) and (AzimuthChange < 0) then
begin
SrcRGB1 := SrcRGB;
if i > 0 then
SrcRGB2 := SrcBmp.ScanLine[i-1]
else
SrcRGB2 := SrcRGB;
end
else if (AzimuthChange >= 0) and (AzimuthChange < 45) then
begin
SrcRGB2 := SrcRGB;
if (i < SrcBmp.Height - 1) then
SrcRGB1 := SrcBmp.ScanLine[i+1]
else
SrcRGB1 := SrcRGB;
end
else if (AzimuthChange >= 45) and (AzimuthChange < 90) then
begin
if (i < SrcBmp.Height - 1) then
SrcRGB1 := SrcBmp.ScanLine[i+1]
else
SrcRGB1 := SrcRGB;
SrcRGB2 := SrcRGB1;
end
else if (AzimuthChange >= 90) and (AzimuthChange < 135) then
begin
if (i < SrcBmp.Height - 1) then
SrcRGB1 := SrcBmp.ScanLine[i+1]
else
SrcRGB1 := SrcRGB;
SrcRGB2 := SrcRGB1;
Inc(SrcRGB1);
end
else if (AzimuthChange >= 135) and (AzimuthChange <= 180) then
begin
if (i < SrcBmp.Height - 1) then
SrcRGB2 := SrcBmp.ScanLine[i+1]
else
SrcRGB2 := SrcRGB;
Inc(SrcRGB2);
SrcRGB1 := SrcRGB;
Inc(SrcRGB1);
end;
for j := 0 to SrcBmp.Width - 1 do
begin
if (AzimuthChange >= -180) and (AzimuthChange < -135) then
begin
Azimuthvalue := AzimuthChange + 180;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= -135) and (AzimuthChange < -90) then
begin
Azimuthvalue := AzimuthChange + 135;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= -90) and (AzimuthChange < -45) then
begin
if j=1 then Inc(SrcRGB1,-1);
Azimuthvalue := AzimuthChange + 90;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= -45) and (AzimuthChange < 0) then
begin
if j=1 then
begin
Inc(SrcRGB1,-1);
Inc(SrcRGB2,-1);
end;
Azimuthvalue := AzimuthChange + 45;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= 0) and (AzimuthChange < 45) then
begin
if j=1 then
begin
Inc(SrcRGB1,-1);
Inc(SrcRGB2,-1);
end;
Azimuthvalue := AzimuthChange;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= 45) and (AzimuthChange < 90) then
begin
if j=1 then Inc(SrcRGB2,-1);
Azimuthvalue := AzimuthChange - 45;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= 90) and (AzimuthChange < 135) then
begin
Azimuthvalue := AzimuthChange - 90;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end
else if (AzimuthChange >= 135) and (AzimuthChange <= 180) then
begin
Azimuthvalue := AzimuthChange - 135;
R:=SrcRGB.rgbtRed-((SrcRGB1.rgbtRed)*Azimuthvalue div 45)-((SrcRGB2.rgbtRed)*(45-Azimuthvalue) div 45)+78;
G:=SrcRGB.rgbtGreen-((SrcRGB1.rgbtGreen)*Azimuthvalue div 45)-((SrcRGB2.rgbtGreen)*(45-Azimuthvalue) div 45)+78;
B:=SrcRGB.rgbtBlue-((SrcRGB1.rgbtBlue)*Azimuthvalue div 45)-((SrcRGB2.rgbtBlue)*(45-Azimuthvalue) div 45)+78;
end;
R:=Min(R,255);
R:=Max(R,0);
G:=Min(G,255);
G:=Max(G,0);
B:=Min(B,255);
B:=Max(B,0);
Gray := (R shr 2) + (R shr 4) + (G shr 1) + (G shr 4) + (B shr 3);
DestRGB.rgbtRed:=Gray;
DestRGB.rgbtGreen:=Gray;
DestRGB.rgbtBlue:=Gray;
if (j<SrcBmp.Width - 1) or not (((AzimuthChange>=-180) and (AzimuthChange<-135)) or ((AzimuthChange>=90) and (AzimuthChange<=180))) then
begin
Inc(SrcRGB1);
end;
if (j<SrcBmp.Width - 1) or not (((AzimuthChange>=135) and (AzimuthChange<180)) or ((AzimuthChange>=-180) and (AzimuthChange<=-90))) then
begin
Inc(SrcRGB2);
end;
Inc(SrcRGB);
Inc(DestRGB);
end;
end;
end;
procedure Emboss(Bmp:TBitmap;AzimuthChange:integer;ElevationChange:integer;WeightChange:integer);overload;
var
DestBmp:TBitmap;
begin
DestBmp:=TBitmap.Create;
DestBmp.Assign(Bmp);
Emboss(Bmp,DestBmp,AzimuthChange,ElevationChange,WeightChange);
Bmp.Assign(DestBmp);
end;
//反色
procedure Negative(Bmp:TBitmap);
var
i, j: Integer;
PRGB: pRGBTriple;
begin
Bmp.PixelFormat:=pf24Bit;
for i := 0 to Bmp.Height - 1 do
begin
PRGB := Bmp.ScanLine;
for j := 0 to Bmp.Width - 1 do
begin
PRGB^.rgbtRed :=not PRGB^.rgbtRed
PRGB^.rgbtGreen :=not PRGB^.rgbtGreen;
PRGB^.rgbtBlue :=not PRGB^.rgbtBlue;
Inc(PRGB);
end;
end;
end;
//曝光
procedure Exposure(Bmp:TBitmap);
var
i, j: integer;
PRGB: pRGBTriple;
begin
Bmp.PixelFormat:=pf24Bit;
for i := 0 to Bmp.Height - 1 do
begin
PRGB := Bmp.ScanLine;
for j := 0 to Bmp.Width - 1 do
begin
if PRGB^.rgbtRed<128 then
PRGB^.rgbtRed :=not PRGB^.rgbtRed
if PRGB^.rgbtGreen<128 then
PRGB^.rgbtGreen :=not PRGB^.rgbtGreen;
if PRGB^.rgbtBlue<128 then
PRGB^.rgbtBlue :=not PRGB^.rgbtBlue;
Inc(PRGB);
end;
end;
end;
//模糊
procedure Blur(SrcBmp:TBitmap);
var
i, j:Integer;
SrcRGB
RGBTriple;SrcNextRGB
RGBTriple;SrcPreRGB
RGBTriple;Value:Integer;
procedure IncRGB;
begin
Inc(SrcPreRGB);
Inc(SrcRGB);
Inc(SrcNextRGB);
end;
procedure DecRGB;
begin
Inc(SrcPreRGB,-1);
Inc(SrcRGB,-1);
Inc(SrcNextRGB,-1);
end;
begin
SrcBmp.PixelFormat:=pf24Bit;
for i := 0 to SrcBmp.Height - 1 do
begin
if i > 0 then
SrcPreRGB:=SrcBmp.ScanLine[i-1]
else
SrcPreRGB := SrcBmp.ScanLine;
SrcRGB := SrcBmp.ScanLine;
if i < SrcBmp.Height - 1 then
SrcNextRGB:=SrcBmp.ScanLine[i+1]
else
SrcNextRGB:=SrcBmp.ScanLine;
for j := 0 to SrcBmp.Width - 1 do
begin
if j > 0 then DecRGB;
Value:=SrcPreRGB.rgbtRed+SrcRGB.rgbtRed+SrcNextRGB.rgbtRed;
if j > 0 then IncRGB;
Value:=Value+SrcPreRGB.rgbtRed+SrcRGB.rgbtRed+SrcNextRGB.rgbtRed;
if j < SrcBmp.Width - 1 then IncRGB;
Value:=(Value+SrcPreRGB.rgbtRed+SrcRGB.rgbtRed+SrcNextRGB.rgbtRed) div 9;
DecRGB;
SrcRGB.rgbtRed:=value;
if j > 0 then DecRGB;
Value:=SrcPreRGB.rgbtGreen+SrcRGB.rgbtGreen+SrcNextRGB.rgbtGreen;
if j > 0 then IncRGB;
Value:=Value+SrcPreRGB.rgbtGreen+SrcRGB.rgbtGreen+SrcNextRGB.rgbtGreen;
if j < SrcBmp.Width - 1 then IncRGB;
Value:=(Value+SrcPreRGB.rgbtGreen+SrcRGB.rgbtGreen+SrcNextRGB.rgbtGreen) div 9;
DecRGB;
SrcRGB.rgbtGreen:=value;
if j > 0 then DecRGB;
Value:=SrcPreRGB.rgbtBlue+SrcRGB.rgbtBlue+SrcNextRGB.rgbtBlue;
if j > 0 then IncRGB;
Value:=Value+SrcPreRGB.rgbtBlue+SrcRGB.rgbtBlue+SrcNextRGB.rgbtBlue;
if j < SrcBmp.Width - 1 then IncRGB;
Value:=(Value+SrcPreRGB.rgbtBlue+SrcRGB.rgbtBlue+SrcNextRGB.rgbtBlue) div 9;
DecRGB;
SrcRGB.rgbtBlue:=value;
IncRGB;
end;
end;
end;
//锐化
procedure Sharpen(SrcBmp:TBitmap);
var
i, j: integer;
SrcRGB: pRGBTriple;
SrcPreRGB: pRGBTriple;
Value: integer;
begin
SrcBmp.PixelFormat:=pf24Bit;
for i := 0 to SrcBmp.Height - 1 do
begin
SrcRGB := SrcBmp.ScanLine;
if i > 0 then
SrcPreRGB:=SrcBmp.ScanLine[i-1]
else
SrcPreRGB:=SrcBmp.ScanLine;
for j := 0 to SrcBmp.Width - 1 do
begin
if j = 1 then Dec(SrcPreRGB);
Value:=SrcRGB.rgbtRed+(SrcRGB.rgbtRed-SrcPreRGB.rgbtRed) div 2;
Value:=Max(0,Value);
Value:=Min(255,Value);
SrcRGB.rgbtRed:=value;
Value:=SrcRGB.rgbtGreen+(SrcRGB.rgbtGreen-SrcPreRGB.rgbtGreen) div 2;
Value:=Max(0,Value);
Value:=Min(255,Value);
SrcRGB.rgbtGreen:=value;
Value:=SrcRGB.rgbtBlue+(SrcRGB.rgbtBlue-SrcPreRGB.rgbtBlue) div 2;
Value:=Max(0,Value);
Value:=Min(255,Value);
SrcRGB.rgbtBlue:=value;
Inc(SrcRGB);
Inc(SrcPreRGB);
end;
end;
end;
由Delphi中的图像灰度化代码看基本图像处理～～～
http://expert.csdn.net/Expert/TopicView1.asp?id=1472467
模糊效果在处理指针移动时有些BUG,现贴出修正后的代码
//模糊
procedure Blur(SrcBmp:TBitmap);
var
i, j:Integer;
SrcRow
RGBTriple;SrcNextRow
RGBTriple;SrcPreRow
RGBTriple;Value:Integer;
procedure IncRow;
begin
Inc(SrcPreRow);
Inc(SrcRow);
Inc(SrcNextRow);
end;
procedure DecRow;
begin
Inc(SrcPreRow,-1);
Inc(SrcRow,-1);
Inc(SrcNextRow,-1);
end;
begin
SrcBmp.PixelFormat:=pf24Bit;
for i := 0 to SrcBmp.Height - 1 do
begin
if i > 0 then
SrcPreRow:=SrcBmp.ScanLine[i-1]
else
SrcPreRow := SrcBmp.ScanLine;
SrcRow := SrcBmp.ScanLine;
if i < SrcBmp.Height - 1 then
SrcNextRow:=SrcBmp.ScanLine[i+1]
else
SrcNextRow:=SrcBmp.ScanLine;
for j := 0 to SrcBmp.Width - 1 do
begin
if j > 0 then DecRow;
Value:=SrcPreRow.rgbtRed+SrcRow.rgbtRed+SrcNextRow.rgbtRed;
if j > 0 then IncRow;
Value:=Value+SrcPreRow.rgbtRed+SrcRow.rgbtRed+SrcNextRow.rgbtRed;
if j < SrcBmp.Width - 1 then IncRow;
Value:=(Value+SrcPreRow.rgbtRed+SrcRow.rgbtRed+SrcNextRow.rgbtRed) div 9;
if j < SrcBmp.Width - 1 then DecRow;
SrcRow.rgbtRed:=value;
if j > 0 then DecRow;
Value:=SrcPreRow.rgbtGreen+SrcRow.rgbtGreen+SrcNextRow.rgbtGreen;
if j > 0 then IncRow;
Value:=Value+SrcPreRow.rgbtGreen+SrcRow.rgbtGreen+SrcNextRow.rgbtGreen;
if j < SrcBmp.Width - 1 then IncRow;
Value:=(Value+SrcPreRow.rgbtGreen+SrcRow.rgbtGreen+SrcNextRow.rgbtGreen) div 9;
if j < SrcBmp.Width - 1 then DecRow;
SrcRow.rgbtGreen:=value;
if j > 0 then DecRow;
Value:=SrcPreRow.rgbtBlue+SrcRow.rgbtBlue+SrcNextRow.rgbtBlue;
if j > 0 then IncRow;
Value:=Value+SrcPreRow.rgbtBlue+SrcRow.rgbtBlue+SrcNextRow.rgbtBlue;
if j < SrcBmp.Width - 1 then IncRow;
Value:=(Value+SrcPreRow.rgbtBlue+SrcRow.rgbtBlue+SrcNextRow.rgbtBlue) div 9;
if j < SrcBmp.Width - 1 then DecRow;
SrcRow.rgbtBlue:=value;
IncRow;
end;
end;
end;
Windows provide two API "GetDeviceGammaRamp/SetDeviceGammaRamp" to perform gamma correction. In fact we need to have an 3 dimension buffer of 256 WORD to manipulate gamma correction. To change gamma it is necessary to change the RGB value of each color contained in the buffer by a float factor between 0.0 and 2.0.
上面的是系统支持的两个API（2000）
http://www.codeproject.com/useritems/gamma_manager.asp
回复人： ehom(？！) ( ) 信誉：128 2003-03-04 19:41:00 得分:0
//修改后的对比度调整代码
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;
DestRow := DestBmp.ScanLine;
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;
Top