php GD库生成分享海报

<?php/** * 图片处理 * @author Administrator * */class ImgGD{ ???/** ????* 创建分享图片 ????*/ ???public function createShareImg(){ ???????// 1 获取背景图尺寸 ???????list($bg_w,$bg_h) = getimagesize("../img/bg.jpg"); ???????// 2 创建画图 ???????$img = @imagecreatetruecolor($bg_w,$bg_h); ???????// 3 填充画布背景颜色 ???????$img_bg_color = imagecolorallocate($img,255,255,255); ???????imagefill($img,0,0,$img_bg_color); ???????// 4 将背景图填充到画布 ???????$bg_img = $this->getImgReource("../img/bg.jpg"); ???????imagecopyresized($img,$bg_img,0,0,0,0,$bg_w,$bg_h,$bg_w,$bg_h); ???????// 5 填空用户二维码 ???????$qrcode = $this->getImgReource("../img/qrcode.png"); ???????// 计算用户二维码所在x轴位置 ???????list($qr_w,$qr_h) = getimagesize("../img/qrcode.png"); ???????$qrcode_des_x = ceil(($bg_w - $qr_w)/2); ???????imagecopyresized($img,$qrcode,$qrcode_des_x,513,0,0,$qr_w,$qr_h,$qr_w,$qr_h); ???????// 6 填充用户信息 ???????$user_img_path = $this->thumbImg("../img/logo.png"); ???????$user_img = $this->getImgReource($user_img_path); ???????list($user_w,$user_h) = getimagesize($user_img_path); ???????imagecopyresized($img,$user_img,13,20,0,0,$user_w,$user_h,$user_w,$user_h); ???????// 填空用户名 ???????$user_name = "王小明"; ???????$font_color = ImageColorAllocate($img,253,254,255); //字体颜色 ???????$font_ttf = "../ziti/HYTangMeiRenJ-2.ttf"; ???????imagettftext($img,23,0,90,50,$font_color,$font_ttf,$user_name); ???????// 7 设置提示语 ???????$tip_text = "邀请你立即关注"; ???????imagettftext($img,17,0,90,80,$font_color,$font_ttf,$tip_text); ???????// 8 输出图片 ???????header("Content-type: image/png"); ???????imagepng($img); ???????// 9 释放空间 ???????imagedestroy($img); ???????imagedestroy($bg_img); ???????imagedestroy($qrcode); ???????imagedestory($user_img); ???} ???/** ????* 获取图像文件资源 ????* @param string $file ????* @return resource ????*/ ???protected function getImgReource($file){ ???????$file_ext = pathinfo($file,PATHINFO_EXTENSION); ???????switch ($file_ext){ ???????????case ‘jpg‘: ???????????case ‘jpeg‘: ???????????????$img_reources = @imagecreatefromjpeg($file); ???????????????break; ???????????case ‘png‘: ???????????????$img_reources = @imagecreatefrompng($file); ???????????????break; ???????????case ‘gif‘: ???????????????$img_reources = @imagecreatefromgif($file); ???????????????break; ???????} ???????return ?$img_reources; ???} ???/** ????* 缩放图片 ????* @param string $img ?????* @param string $file ????* @param number $th_w ????* @param number $th_h ????* @return boolean|string; ????*/ ???protected function thumbImg($img,$file=‘./‘,$th_w=62,$th_h=62){ ???????//给图像加大1像素的边框 ???????$new_th_h = $th_h + 4; ???????$new_th_w = $th_w + 4; ???????// 获取大图资源及图像大小 ???????list($max_w,$max_h) = getimagesize($img); ???????if($max_w < $th_w || $max_h < $th_h) return false; ???????$max_img = $this->getImgReource($img); ???????//新建真色彩画布 ???????$min_img = @imagecreatetruecolor($new_th_w,$new_th_h); ???????$bg_color = ImageColorAllocate($min_img,255,255,255); ???????imagefill($min_img,0,0,$bg_color);// ????????imagesavealpha($min_img,true); ???????imagecolortransparent($min_img,$bg_color); ????????imagecopyresampled($min_img,$max_img,2,2,0,0,$th_w,$th_h,$max_w,$max_h); ???????//输出图像到文件 ???????$min_img_path = $file . ‘thunm_‘.time().‘.png‘; ???????imagepng($min_img,$min_img_path); ???????if(!is_file($min_img_path)){ ???????????return false; ???????} ???????//释放空间 ???????imagedestroy($max_img); ???????imagedestroy($min_img); ???????return $min_img_path; ???}}//调用$gd_img = new ImgGD();$gd_img->createShareImg();

使用到的函数：
使用到的GD函数：

getimagesize()：该函数获取图像大小

imagecreatetruecolor() : 创建真色彩图像? ?imagecolorallocate():使用这个函数创建的图像画布图片会丢失色彩?

?imagecolorallocate() : 该函数用来设置颜色

imagecopyresized() : 拷贝图像调整图像大小

imagettftext() : 设置文本到图像上

imagepng() ： 输出图像为png格式??imagejpeg() : 输出为jpg格式??imagegif() : 输出为gif格式

如果直接输出图像要添加一句代码： header("Content-type: image/png");

imagedestroy() : 该函数销毁图像释放内存空间资源

imagecreatefromjpeg() : 该函数获取jpg格式图像对应的图像资源

imagecreatefrompng() :?该函数获取png格式图像对应的图像资源

imagecreatefromgif() :?该函数获取gif格式图像对应的图像资源

具体函数的使用可以参考php手册

php GD库生成分享海报

原文地址：http://blog.51cto.com/11016194/2327966