php生成缩略图，加水印种

php生成缩略图，加水印种

php生成缩略图，加水印类

这个一个简单的GD库操作

 $dinfo['height'] || $winfo['width'] > $dinfo['width']) {
			return false;
		}

		// 两张图,读到画布上! 但是图片可能是png,可能是jpeg,用什么函数读?
		$dfunc = 'imagecreatefrom' . $dinfo['ext'];
		$wfunc = 'imagecreatefrom' . $winfo['ext'];

		if (!function_exists($dfunc) || !function_exists($wfunc)) {
			return false;
		}

		// 动态加载函数来创建画布
		$dim = $dfunc($dst);
		// 创建待操作的画布
		$wim = $wfunc($water);
		// 创建水印画布

		// 根据水印的位置 计算粘贴的坐标
		switch($pos) {
			case 0 :
				// 左上角
				$posx = 0;
				$posy = 0;
				break;

			case 1 :
				// 右上角
				$posx = $dinfo['width'] - $winfo['width'];
				$posy = 0;
				break;

			case 3 :
				// 左下角
				$posx = 0;
				$posy = $dinfo['height'] - $winfo['height'];
				break;

			default :
				$posx = $dinfo['width'] - $winfo['width'];
				$posy = $dinfo['height'] - $winfo['height'];
		}

		// 加水印
		imagecopymerge($dim, $wim, $posx, $posy, 0, 0, $winfo['width'], $winfo['height'], $alpha);

		// 保存
		if (!$save) {
			$save = $dst;
			unlink($dst);
			// 删除原图
		}

		$createfunc = 'image' . $dinfo['ext'];
		$createfunc($dim, $save);

		imagedestroy($dim);
		imagedestroy($wim);

		return true;
	}

	/**
	 thumb 生成缩略图
	 等比例缩放,两边留白
	 **/
	public static function thumb($dst, $save = NULL, $width = 200, $height = 200) {
		// 首先判断待处理的图片存不存在
		$dinfo = self::imageInfo($dst);
		if ($dinfo == false) {
			return false;
		}

		// 计算缩放比例
		$calc = min($width / $dinfo['width'], $height / $dinfo['height']);

		// 创建原始图的画布
		$dfunc = 'imagecreatefrom' . $dinfo['ext'];
		$dim = $dfunc($dst);

		// 创建缩略画布
		$tim = imagecreatetruecolor($width, $height);

		// 创建白色填充缩略画布
		$white = imagecolorallocate($tim, 255, 255, 255);

		// 填充缩略画布
		imagefill($tim, 0, 0, $white);

		// 复制并缩略
		$dwidth = (int)$dinfo['width'] * $calc;
		$dheight = (int)$dinfo['height'] * $calc;

		$paddingx = (int)($width - $dwidth) / 2;
		$paddingy = (int)($height - $dheight) / 2;

		imagecopyresampled($tim, $dim, $paddingx, $paddingy, 0, 0, $dwidth, $dheight, $dinfo['width'], $dinfo['height']);

		// 保存图片
		if (!$save) {
			$save = $dst;
			unlink($dst);
		}

		$createfunc = 'image' . $dinfo['ext'];
		$createfunc($tim, $save);

		imagedestroy($dim);
		imagedestroy($tim);

		return true;

	}

}

// print_r(ImageTool::imageInfo('./home.jpg'));
/*
 echo ImageTool::water('./home.jpg','./smallfeng.png','home1.jpg',0)?'OK':'FAIL';
 echo ImageTool::water('./home.jpg','./smallfeng.png','home2.jpg',1)?'OK':'FAIL';
 echo ImageTool::water('./home.jpg','./smallfeng.png','home3.jpg',2)?'OK':'FAIL';
 echo ImageTool::water('./home.jpg','./smallfeng.png','home4.jpg',3)?'OK':'FAIL';
 */