基本圖象處理代碼(2)

2019-11-18 18:37:39

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[亮度、對比度、飽和度的調整]

//亮度調整
PRocedure BrightnessChange(const SrcBmp,DestBmp:TBitmap;ValueChange:integer);
var
i, j: integer;
SrcRGB, DestRGB: pRGBTriple;
Table: array[0..255]of Byte;
begin
if ValueChange > 0 then
    for i := 0 to 255 do
      Table[i]:=Byte(i + ((ValueChange * (i xor 255)) shr 8))
else
    for i := 0 to 255 do
      Table[i]:=Byte(i - ((Abs(ValueChange) * i) shr 8));
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
      DestRGB^.rgbtRed := Table[SrcRGB^.rgbtRed];
      DestRGB^.rgbtGreen := Table[SrcRGB^.rgbtGreen];
      DestRGB^.rgbtBlue := Table[SrcRGB^.rgbtBlue];
      Inc(SrcRGB);
      Inc(DestRGB);
    end;
end;
end;

//對比度調整
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;

//飽和度調整
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調整
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;

如果有些圖像處理的基礎，這些代碼都比較好理解，主要是三原色的值不要超過(0-255)的范圍，有些朋友沒有注意這問題，當超過范圍后，會出現些難看的“色斑”！

[顏色調整]

//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(加權)
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;