function image_contour_alpha($im, $coul='000000', $trait=1)
{
	$image = valeurs_image_trans($im, "contour-$coul-$trait", "png");
	if (!$image) return("");

	include_ecrire("filtres");
	$couleurs = couleur_hex_to_dec($coul);
	$dr= $couleurs["red"];
	$dv= $couleurs["green"];
	$db= $couleurs["blue"];
	
	$x_i = $image["largeur"];
	$y_i = $image["hauteur"];
	
	$im = $image["fichier"];
	$dest = $image["fichier_dest"];
	
	$creer = $image["creer"];
	
	if ($creer) {
		$im = $image["fonction_imagecreatefrom"]($im);
		$im_ = imagecreatetruecolor($x_i, $y_i);
		@imagealphablending($im_, false);
		@imagesavealpha($im_,true);
		$color_t = ImageColorAllocateAlpha( $im_, 255, 255, 255 , 127 );
		imagefill ($im_, 0, 0, $color_t);

		for ($x = 0; $x < $x_i; $x++) {
			for ($y=0; $y < $y_i; $y++) {
			
				$rgb = ImageColorAt($im, $x, $y);
				$a = ($rgb >> 24) & 0xFF;
				
				$dif = false;
				$m = 0;
				$t = 0;
				for ($ix = -1*$trait/2; $ix <= $trait/2; $ix++) {
					for ($iy = -1*$trait/2; $iy <= $trait/2; $iy++) {
						$x2 = $x + $ix;
						$y2 = $y + $iy;
						if ($x2 >=0 AND $y2 >= 0 AND $x2 < $x_i AND $y2  < $y_i) {
						$t++;
							$rgb2 = ImageColorAt($im, $x2, $y2);
							$a2 = ($rgb2 >> 24) & 0xFF;
							$r2 = ($rgb2 >> 16) & 0xFF;
							$g2 = ($rgb2 >> 8) & 0xFF;
							$b2 = $rgb2 & 0xFF;
	
							if ($a != $a2) {
								$dx = min(abs($ix),abs($iy));
								$dy = max(abs($ix),abs($iy));
								if ($mem[$dx][$dy]) $d = $mem[$dx][$dy];
								else {
									$mem[$dx][$dy] = sqrt(($dx)*($dx)+($dy)*($dy));
									$d = $mem[$dx][$dy];
								}
								if ($d>0) {
									$m = $m + (abs($a2-$a) / $d);
								} else {
									$m = $m + 127;
								}
							}
						}
					}
				}
				$m = 127 - (($m / $t) * $trait);
				$m = min(max($m, 0), 127);
										
				$color = ImageColorAllocateAlpha( $im_, $dr, $dv, $db , round($m) );
				imagesetpixel ($im_, $x, $y, $color);			
			}
		}
		$image["fonction_image"]($im_, "$dest");
	}

	$class = $image["class"];
	if (strlen($class) > 1) $tags=" class='$class'";
	$tags = "$tags alt='".$image["alt"]."'";
	$style = $image["style"];
	if (strlen($style) > 1) $tags="$tags style='$style'";
	
	return "<img src='$dest'$tags />";
}