Подскажите пожалуйста, как исправить ошибку (Notice: imagecolorat(): 550,0 is out of bounds in)

Как исправить данную ошибку?

Notice: imagecolorat(): 550,0 is out of bounds in /Applications/XAMPP/xamppfiles/htdocs/
вот код:
$path = '1.jpg';
$size = getimagesize($path);
$img = imagecreatefromjpeg($path);


$x = 0;
$y = 0;
$color = array();
for ($i = 1; $i < $size[0] * $size[1]; $i++) {

$color_index = imagecolorat($img, $x, $y); //16777215
$color_tran = imagecolorsforindex($img, $color_index);

if (($color_tran['red'] == 0 && $color_tran['green'] == 0 && $color_tran['blue'] == 0)
or
($color_tran['red'] <= 255 && $color_tran['red'] >= 235 &&
$color_tran['green'] <= 255 && $color_tran['green'] >= 235 &&
$color_tran['blue'] <= 255 && $color_tran['blue'] >= 235)
or
($color_tran['red'] >= 190 && $color_tran['red'] <= 230 &&
$color_tran['green'] >= 225 && $color_tran['green'] <= 245 &&
$color_tran['blue'] >= 245 && $color_tran['blue'] <= 255)
) {
$color[$x][$y] = 1;
} else {
$color[$x][$y] = 1;
}

$x++;
if ($x > $size[0]) {
$x = 1;
$y++;
}
}

 

спасибо.