Computer Graphics:reflection along y axis

//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
int i,j;
int ht=Image1->Height;
int wt=Image1->Width;
for(i=0;i<ht;i++)
{
for(j=0;j<wt;j++)
{
Image2->Canvas->Pixels[wt-i][j]=Image1->Canvas->Pixels[i][j];
}
}
}
//---------------------------------------------------------------------------