<!-- サンプルコード -->
<?php
$image = ImageCreate(300,300);
$GrayArea = ImageColorAllocate($image,0xAA,0xAA,0xAA);
$blackArea = ImageColorAllocate($image,0x00,0x00,0x00);
ImageFilledRectangle($image,50,50,250,250,$blackArea);
header('Content-Type: image/png');
ImagePNG($image);
?>
