<?php
	function isImageBright($imagePath, $sampleRate = 10) {
		// Charger l'image
		$image = imagecreatefrompng($imagePath);
		if (!$image) return false;

		$width = imagesx($image);
		$height = imagesy($image);

		$totalBrightness = 0;
		$count = 0;

		// Parcourir l'image avec un pas (échantillonnage)
		for ($x = 0; $x < $width; $x += $sampleRate) {
			for ($y = 0; $y < $height; $y += $sampleRate) {
				$rgb = imagecolorat($image, $x, $y);
				$r = ($rgb >> 16) & 0xFF;
				$g = ($rgb >> 8) & 0xFF;
				$b = $rgb & 0xFF;

				// Formule de luminance relative
				$brightness = (0.299 * $r + 0.587 * $g + 0.114 * $b);
				$totalBrightness += $brightness;
				$count++;
			}
		}

		imagedestroy($image);

		$averageBrightness = $totalBrightness / $count;
		// echo  'averageBrightness = ' .$averageBrightness;

		// Seuil : 128 est généralement un bon point de séparation
		return $averageBrightness > 9;
	}
?>