//Histogram - zmiana ekspozycji
//(c) 2008 Tomasz Lubinski
//www.algorytm.org
//---------------------------------------------------------------------------
#include <vcl.h>
#include <math.h>
#pragma hdrstop
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------


double LUT[256];

//---------------------------------------------------------------------------
//wyswietl wartosci tablicy LUT
void TForm1::UpdateLUT()
{
Chart3->SeriesList->Series[0]->Clear();
Chart3->SeriesList->Series[0]->AddArray(LUT, 255);
}

//---------------------------------------------------------------------------
//zmień wartosc kontrastu i przelicz nowe wartosci tablicy LUT
void __fastcall TForm1::UpDown1Click(TObject *Sender, TUDBtnType Button)
{
int i;
double a;
a = StrToFloat(Edit1->Text);
if (Button == btNext)
    a += 0.05;
else
    a -= 0.05;

if (a < 0.05)
    a = 0.05;

Edit1->Text = FloatToStr(a);
for (i=0; i<256; i++)
    if ((a*i) > 255)
        LUT[i] = 255;
    else
        LUT[i] = a*i;
UpdateLUT();
}

//---------------------------------------------------------------------------
//zainicjuj tablice LUT
void __fastcall TForm1::FormCreate(TObject *Sender)
{
int i;
for (i=0; i<256; i++)
    LUT[i] = i;
UpdateLUT();
}

//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int i, j, rvalue, gvalue, bvalue, grayvalue;
double r[256], g[256], b[256], gray[256];
TColor color;

for (i=0; i<256; i++)
{
    r[i] = 0;
    g[i] = 0;
    b[i] = 0;
    gray[i] = 0;
}

for (i=0; i<ObrazKolorowy->Width; i++)
    for (j=0; j<ObrazKolorowy->Height; j++)
    {
        color = ObrazKolorowy->Canvas->Pixels[i][j];
        rvalue = GetRValue(color);
        gvalue = GetGValue(color);
        bvalue = GetBValue(color);
        //zmien wartosc wedlug tablicy LUT
        color = (TColor)(LUT[rvalue] +
                   ((int)LUT[gvalue] << 8) +
                   ((int)LUT[bvalue] << 16));
        //oblicz histogram
        WynikKolorowy->Canvas->Pixels[i][j] = color;
        r[GetRValue(color)]++;
        g[GetGValue(color)]++;
        b[GetBValue(color)]++;
   }
Histogram1->SeriesList->Series[0]->Clear();
Histogram1->SeriesList->Series[1]->Clear();
Histogram1->SeriesList->Series[2]->Clear();
Histogram1->SeriesList->Series[0]->AddArray(r, 255);
Histogram1->SeriesList->Series[1]->AddArray(g, 255);
Histogram1->SeriesList->Series[2]->AddArray(b, 255);

for (i=0; i<ObrazMono->Width; i++)
    for (j=0; j<ObrazMono->Height; j++)
    {
        color = ObrazMono->Canvas->Pixels[i][j];
        grayvalue = GetRValue(color);
        //zmien wartosc wedlug tablicy LUT
        color = (TColor) LUT[grayvalue] +
                   ((int)LUT[grayvalue] << 8) +
                   ((int)LUT[grayvalue] << 16);
        //oblicz histogram
        WynikMono->Canvas->Pixels[i][j] = color;
        gray[GetRValue(color)]++;
    }
Histogram2->SeriesList->Series[0]->Clear();
Histogram2->SeriesList->Series[0]->AddArray(gray, 255);
}
//---------------------------------------------------------------------------