copying a image pixel by pixel

[cohs]

can someone tell me why this only prints a black rectangle.

<?php
header("Content-type: image/jpg");
 $a = imagecreatefromjpeg("c:\C.jpg");

$x = imagesx($a);
$y = imagesy($a);

$new = imagecreatetruecolor($x,$y);
imagepalettecopy($new,$a);

for ($count2 =1; $count2 >=$y;$count2++){
for ($count = 1;$count >= $x;$count++){


$pixel = imagecolorat($a,$count,$count2);
$pix = imagecolorsforindex($a,$pixel);
$color = imagecolorallocate($new,$pix['red'],$pix['green'],$pix['blue']);

imagecolorset($new,$pix,$pix['red'],$pix['green'],$pix['blue']);

}
}


imagejpeg($new,"c:/test.jpg");


?>

i know its messy but i was moving things around to see what was wrong.

i updated the code a little bit. now when i try to runt he script it prompts me to download the script. 🙁

[wilku]

Jpeg is a true color image i.e. it has no palette of colors. It stores red, green, blue values for every pixel (before compression I mean).
To get RGB values for true color pictures use this (from php manual):

$rgb = imagecolorat($im, 10, 15);
$r = ($rgb >> 16) & 0xFF;
$g = ($rgb >> 8) & 0xFF;
$b = $rgb & 0xFF;

You don't allocate colors for true color images. I think you just need to use $rgb in imagesetpixel (instead of imagecolorset).