unit Unit16;

interface
uses windows,Graphics,comctrls;
const
MaxPixelCount = 32768;
type
pRGBArray = ^TRGBArray;
TRGBArray = ARRAY[0..MaxPixelCount-1] OF TRGBTriple;
function Min(a, b: integer): integer;
function Max(a, b: integer): integer;


procedure RGBChange(SrcBmp,DestBmp:Tbitmap;RedChange,GreenChange,
BlueChange:integer);overload;
procedure RGBChange(SrcBmp:Tbitmap;RedChange,GreenChange,BlueChange:integer;
AProgressBar:TProgressBar); overload;

procedure BrightnessChange(SrcBmp,DestBmp:Tbitmap;ValueChange:integer); overload;
procedure BrightnessChange(SrcBmp:Tbitmap;ValueChange:integer;
AProgressBar:TProgressBar); overload;
procedure ContrastChange(SrcBmp,DestBmp:Tbitmap;ValueChange:integer); overload;
procedure ContrastChange(SrcBmp:Tbitmap;ValueChange:integer;
AProgressBar:TProgressBar); overload;
implementation

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;

//rgb色彩
procedure RGBChange(SrcBmp,DestBmp:Tbitmap;RedChange,GreenChange,BlueChange:integer);
var
// R,G,B:integer;
SrcRow, DestRow:pRGBArray;
i,j:integer;
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
// add brightness value to pixel's RGB values
if RedChange> 0 then
DestRow[j].rgbtRed := Min(255, SrcRow[j].rgbtRed + RedChange)
else
DestRow[j].rgbtRed := Max(0, SrcRow[j].rgbtRed + RedChange);

if GreenChange> 0 then
DestRow[j].rgbtGreen := Min(255, SrcRow[j].rgbtGreen +GreenChange)
else
DestRow[j].rgbtGreen := Max(0, SrcRow[j].rgbtGreen +GreenChange);

if BlueChange> 0 then
DestRow[j].rgbtBlue := Min(255, SrcRow[j].rgbtBlue +BlueChange)
else
DestRow[j].rgbtBlue := Max(0, SrcRow[j].rgbtBlue +BlueChange);

end;
end;
end;

//rgb色彩
procedure RGBChange(SrcBmp:Tbitmap;RedChange,GreenChange,BlueChange:integer;AProgressBar:TProgressBar); overload;
var
// R,G,B:integer;
SrcRow :pRGBArray;
i,j:integer;
begin
AProgressBar.Max:=SrcBmp.Height- 1;
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
// add brightness value to pixel's RGB values
if RedChange> 0 then
SrcRow[j].rgbtRed := Min(255, SrcRow[j].rgbtRed + RedChange)
else
SrcRow[j].rgbtRed := Max(0, SrcRow[j].rgbtRed + RedChange);

if GreenChange> 0 then
SrcRow[j].rgbtGreen := Min(255, SrcRow[j].rgbtGreen +GreenChange)
else
SrcRow[j].rgbtGreen := Max(0, SrcRow[j].rgbtGreen +GreenChange);

if BlueChange> 0 then
SrcRow[j].rgbtBlue := Min(255, SrcRow[j].rgbtBlue +BlueChange)
else
SrcRow[j].rgbtBlue := Max(0, SrcRow[j].rgbtBlue +BlueChange);

end;
AProgressBar.Position:=i;
end;

end;


//亮度
procedure BrightnessChange(SrcBmp,DestBmp:Tbitmap;ValueChange:integer);
var
i, j: integer;
SrcRow, DestRow: pRGBArray;
begin
// get brightness increment value

// for each row of pixels
for i := 0 to SrcBmp.Height - 1 do
begin
SrcRow := SrcBmp.ScanLine[i];
DestRow := DestBmp.ScanLine[i];

// for each pixel in row
for j := 0 to SrcBmp.Width - 1 do
begin
// add brightness value to pixel's RGB values
if ValueChange > 0 then
begin
// RGB values must be less than 256
DestRow[j].rgbtRed := Min(255, SrcRow[j].rgbtRed +ValueChange);
DestRow[j].rgbtGreen := Min(255, SrcRow[j].rgbtGreen + ValueChange);
DestRow[j].rgbtBlue := Min(255, SrcRow[j].rgbtBlue +ValueChange);
end else begin
// RGB values must be greater or equal than 0
DestRow[j].rgbtRed := Max(0, SrcRow[j].rgbtRed +ValueChange);
DestRow[j].rgbtGreen := Max(0, SrcRow[j].rgbtGreen +ValueChange);
DestRow[j].rgbtBlue := Max(0, SrcRow[j].rgbtBlue +ValueChange);
end;
end;
end;
end;

//对比度
procedure ContrastChange(SrcBmp,DestBmp:Tbitmap;ValueChange:integer);
var
X, Y: Integer;
SrcRow,DestRow: pRGBArray;
begin
if valuechange>=0
then
begin

//AProgressBar.Max:=SrcBmp.Height - 1;
for Y := 0 to SrcBmp.Height - 1 do
begin
SrcRow := SrcBmp.ScanLine[Y];
DestRow:=DestBmp.ScanLine[y];
for X := 0 to SrcBmp.Width - 1 do
begin
if SrcRow[x].rgbtRed>=128 then DestRow[x].rgbtRed:=min(255,SrcRow[x].rgbtRed+ValueChange)
else
DestRow[x].rgbtRed:=max(0,SrcRow[x].rgbtRed-ValueChange);

if SrcRow[x].rgbtGreen>=128 then DestRow[x].rgbtGreen:=min(255,SrcRow[x].rgbtGreen+ValueChange)
else
DestRow[x].rgbtGreen:=max(0,SrcRow[x].rgbtGreen-ValueChange);
if SrcRow[x].rgbtBlue>=128 then DestRow[x].rgbtBlue:=min(255,SrcRow[x].rgbtBlue+ValueChange)
else
DestRow[x].rgbtBlue:=max(0,SrcRow[x].rgbtBlue-ValueChange);

end;
end;
end
else
begin
//AProgressBar.Position:=0;
//AProgressBar.Max:=SrcBmp.Height - 1;

for Y := 0 to SrcBmp.Height - 1 do
begin
SrcRow := SrcBmp.ScanLine[Y];
DestRow:=DestBmp.ScanLine[y];
for X := 0 to SrcBmp.Width - 1 do
begin
DestRow[x].rgbtRed:=min(128,SrcRow[x].rgbtRed-ValueChange);
DestRow[x].rgbtGreen:=min(128,SrcRow[x].rgbtGreen-ValueChange);
DestRow[x].rgbtBlue:=min(128,SrcRow[x].rgbtBlue-ValueChange);
end;

end;

end;
end;