Zoom In help!!!

Hi there. I am creating a simple image editor in Netbeans 4.1. I have a Frame which has a panel listing options to the user such as Zoom In, Zoom Out, Set the picture to black and white etc. I then have a panel where images are loaded to and edited. I am in the process of making the Zoom In function work. I have set up the code in the frame and have been given the code for the panel with gaps that we need to fill in. My problem is that I can't get it to work. Below is the code

public void zoomIn() {
int row, column;
int r = 0, g = 1, b = 2; // To access arrays easily
int tLeft = 0, tRight = 4;
int mLeft = 0, mMid = 4, mRight = 8;
int cMod, cTemp;
// The counter for the actual array element, with RGBA as 4 entries
int block;
// One block of pixels to be expanded at a time
int rowTemp, rowModified;
int wmaxT, wmaxM;

if(zoomLevel > rowModified) return; // Cannot zoom any further
gTempBuffer.drawImage(myModifiedBuffer, 0, 0, this);
gModifiedBuffer.setColor(Color.white);
gModifiedBuffer.fillRect(0, 0, dPanel.width, dPanel.height);

hmax = myHeight[zoomLevel + 1]; // The zoomed height
if(hmax > dPanel.height) { // Keep to panel height
hmax = dPanel.height - dPanel.height / 3;
// Keep zoomed image to panel height
} else {
hmax = myHeight[zoomLevel];
}

wmaxT = myWidth[zoomLevel + 1];
if(wmaxT > dPanel.width) {
wmaxT = dPanel.width - dPanel.width/ 3;
} else {
wmaxT = myWidth[zoomLevel];
}

wmaxM = Math.min(myWidth[zoomLevel + 1], dPanel.width);

myTempRaster = myTempBuffer.getRaster();
myModifiedRaster = myModifiedBuffer.getRaster();
for( row = 0; row < (hmax / 2) - 1; row++){ // -1 to keep in range
rowTemp = row * 2; // 2 rows per pass
rowModified = row * 3; // 3 rows per pass

myTempRaster.getPixels(0, rowTemp, wmaxT, 1, myTempRasterArrayTop); // Top row to top array
myTempRaster.getPixels(0, rowTemp + 1, wmaxT, 1, myTempRasterArrayBot); // Bottom row to bot array
myModifiedRaster.getPixels(0, rowModified, wmaxM, 1, myModifiedRasterArrayTop); // Top row to top array
myModifiedRaster.getPixels(0, rowModified + 1, wmaxM, 1, myModifiedRasterArrayMid); // Bottom row to bot array
myModifiedRaster.getPixels(0, rowModified + 2, wmaxM, 1, myModifiedRasterArrayBot);

for(block = 0; block < wmaxT / 2; block++) { // Block is a pair of pixels
cTemp = block * 2 * 4;
// block counts 4 rgba entries to the array and 2 pixels
cMod = block * 3 * 4; // Modified block is 3 pixels * 4(rgba)

for(red = 0; red < 3; red++) {
myModifiedRasterArrayTop[cMod + red + mLeft] // Top left
= myTempRasterArrayTop[cTemp + red + tLeft];

myModifiedRasterArrayTop[cMod + red + mMid] = 0; // top middle

myModifiedRasterArrayTop[cMod + red + mRight] = // top right
myTempRasterArrayTop[cTemp + red + tRight];

myModifiedRasterArrayMid[cMod + red + mLeft] = 0; // middle left


myModifiedRasterArrayMid[cMod + red + mRight] = 0; // middle right

myModifiedRasterArrayBot[cMod + red + mLeft] = // bottom left
myTempRasterArrayBot[cTemp + red + tLeft];

myModifiedRasterArrayBot[cMod + red + mMid] = 0; // bottom middle

myModifiedRasterArrayBot[cMod + red + mRight] = // bottom right
myTempRasterArrayBot[cTemp + red + tRight];

myModifiedRasterArrayMid[cMod + red + mMid] = 0; // middle middle
}
}
myModifiedRaster.setPixels(0, rowModified, wmaxM, 1,
myModifiedRasterArrayTop);

myModifiedRaster.setPixels(0, rowModified + 1, wmaxM, 1,
myModifiedRasterArrayMid);

myModifiedRaster.setPixels(0, rowModified + 2, wmaxM, 1,
myModifiedRasterArrayBot);
}
zoomLevel++;
paintComponent(this.getGraphics());
}

Any Ideas?
Many thanks in advance for any responses i get