php图像处理函数实例大全及php验证码

$im = imagecreatetruecolor(500, 300); //准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $white = imagecolorallocate($im, 255, 255, 255); //背景填充成黑色 imagefill($im,0,0, $black); //画一个矩形,填充成白色 imagefilledellipse($im, 258, 151, 200, 200, $white); //输出到浏览器或保存起来 header("content-type:image/png"); //输出图片 imagepng($im); //关闭画布 imagedestroy($im); ?> 复制代码数学函数:1，max();2，min();3，mt_rand();随机取一个数字 ?> 复制代码mt_rand随机取一个值 $arr = array("a","b","c","d","e"); $rkey = mt_rand(0,count($arr)-1); echo $arr[$rkey]; ?> 复制代码4.ceil();天花板 5.floor();6.round();四舍五入 echo floor(2.4);//2 echo round(2.4);//2 echo round(2.6);//3 ?> 复制代码6.pi(); //π 取圆周率 echo M_PI; ?> 复制代码图片处理函数使用场景1.验证码2.缩放3.裁剪4.水印例子： $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 //如果不填充背景,默认是黑色 imageellipse($im,258,151,200,200,$white); //4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码绘制图像:imagefill();imagesetpixel();//画像素点imageline();//画线imagerectangle();//画一个矩形imagepolygon();//画一个多边形imageellipse();//画一个椭圆imageare();画一个圆弧imagechar();//水平的画一个字符imagestring();//水平的画一行字符串例子： //画线 $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 //如果不填充背景,默认是黑色 imageline($im,0,0,500,300,$white); imageline($im,0,300,500,0,$white); imageline($im,0,150,500,150,$white); imageline($im,250,0,250,300,$white); //4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码例子： //添加干扰素 $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 //产生随机的点 for ($i=0; $i imagesetpixel($im,mt_rand(0,500),mt_rand(0,300),$white); } //产生随机的线 for ($j=0; $j imageline($im, mt_rand(0,500), mt_rand(0,300), mt_rand(0,500), mt_rand(0,300), $white); }//4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码例子： //画矩形: $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 imagerectangle($im, 20, 20, 480, 280, $white);// imagefilledrectangle($im, 20, 20, 480, 280, $white);//填充 //4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码例子： //imagepolygon 画多边形_画三角形 $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 $arr = array( 250,20, 60,240, 440,240 ); imagepolygon($im, $arr, 3, $white); //4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码例子，画一个3D饼状图 $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $red = imagecolorallocate($im, 255, 0, 0); $grayred = imagecolorallocate($im, 255, 100, 100); $green = imagecolorallocate($im, 0, 255, 0); $blue = imagecolorallocate($im, 0, 0, 255); $gray = imagecolorallocate($im, 200, 200, 200); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 for ($i=0; $i imagefilledarc($im, 250, 150+$i, 200, 200, 0, 70, $gray,IMG_ARC_PIE); imagefilledarc($im, 250, 150+$i, 200, 200, 70, 190, $grayred,IMG_ARC_PIE); imagefilledarc($im, 250, 150+$i, 200, 200, 190, 270, $green,IMG_ARC_PIE); imagefilledarc($im, 250, 150+$i, 200, 200, 270, 360, $blue,IMG_ARC_PIE); } imagefilledarc($im, 250, 150, 200, 200, 0, 70, $white,IMG_ARC_PIE); imagefilledarc($im, 250, 150, 200, 200, 70, 190, $red,IMG_ARC_PIE); imagefilledarc($im, 250, 150, 200, 200, 190, 270, $green,IMG_ARC_PIE); imagefilledarc($im, 250, 150, 200, 200, 270, 360, $blue,IMG_ARC_PIE); //4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码例子： //写文字: $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $red = imagecolorallocate($im, 255, 0, 0); $grayred = imagecolorallocate($im, 255, 100, 100); $green = imagecolorallocate($im, 0, 255, 0); $blue = imagecolorallocate($im, 0, 0, 255); $gray = imagecolorallocate($im, 200, 200, 200); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 $str= "imagestring($im, 5, 260, 160, $str, $green); //4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码例子： //写单个字符: $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $red = imagecolorallocate($im, 255, 0, 0); $grayred = imagecolorallocate($im, 255, 100, 100); $green = imagecolorallocate($im, 0, 255, 0); $blue = imagecolorallocate($im, 0, 0, 255); $gray = imagecolorallocate($im, 200, 200, 200); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 $str= "P"; imagechar($im, 5, 260, 160, $str, $green); //4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码例子， //在图片上面写字 $im = imagecreatetruecolor(500,300); //2.准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $red = imagecolorallocate($im, 255, 0, 0); $grayred = imagecolorallocate($im, 255, 100, 100); $green = imagecolorallocate($im, 0, 255, 0); $blue = imagecolorallocate($im, 0, 0, 255); $gray = imagecolorallocate($im, 200, 200, 200); $white = imagecolorallocate($im, 255, 255, 255); //3.在画布上画图像或者文字 $str= "junzaivip"; $file = "E:/// $file = "fonts/SIMYOU.TTF"; imagettftext($im, 50, 0, 100, 200, $green, $file, $str); //4.输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //5.释放画布资源 imagedestroy($im); ?> 复制代码$im = imagecreatetruecolor(100,50); //准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $gray = imagecolorallocate($im, 200, 200, 200); //填充背景 imagefill($im, 0, 0, $gray); //文字坐标 $x = (100-4*20)/2 + 6; $y = (50-20)/2 + 20; //在画布上画图像或者文字 //把三个数组联系起来 $strarr = array_merge(range(1, 9),range(a, z),range(A, Z)); //打乱数组 shuffle($strarr); //array_slice:取数组的前几位 //Join 将数组变成字符串,并且以第一个变量做分隔符 $str = join('',array_slice($strarr, 0,4)); $file = "E:/// $file = "fonts/msyh.ttf"; imagettftext($im, 20, 0, $x, $y, $black, $file, $str); //输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //释放画布资源 imagedestroy($im); ?> 复制代码这个验证码版本只实现了验证图片的动态获取前台注册页面的验证码和生成图片的验证码进行比较验证码是由数字 小写字母 大写字母 随机组成index. reg table{ border-collapse: collapse; } 用户注册页面 姓 名: 密 码: 验证码: 复制代码reg.// echo $_POST['username']; // echo $_POST['password']; $code = strtolower($_POST['vcode']); // echo $code; // echo "// print_r($_SESSION); // echo "登录后复制"; $vstr = strtolower($_SESSION['vstr']); if ($code==$vstr) { //实现页面的跳转 echo "location='http://www.xingzuo51.com'"; }else{ echo "alert('验证码输入错误')"; //echo ""; echo "location='index."; } ?> 复制代码auth.session_start(); $width = 50;//验证码背景宽度 $height = 26;//验证码背景高速 $fonttype = 10;//验证码中字的大小 //准备画布 $im = imagecreatetruecolor($width,$height); //准备涂料 $black = imagecolorallocate($im, 0, 0, 0); $gray = imagecolorallocate($im, 200, 200, 200); //填充背景 imagefill($im, 0, 0, $gray); //文字坐标 $x = ($width-4*$fonttype)/2 +2; $y = ($height-$fonttype)/2 + $fonttype; //在画布上画图像或者文字 //把三个数组联系起来 $strarr = array_merge(range(1, 9),range(a, z),range(A, Z)); //打乱数组 shuffle($strarr); //array_slice:取数组的前几位 //Join 将数组变成字符串,并且以第一个变量做分隔符 $str = join('',array_slice($strarr, 0,4)); //把$str放入session中,可方便所有页面使用 $_SESSION['vstr'] = $str; $file = "E:/// $file = "fonts/msyh.ttf"; imagettftext($im, $fonttype, 0, $x, $y, $black, $file, $str); //输出最终图像或保存最终图像 header("content-type:image/png"); imagepng($im); //释放画布资源 imagedestroy($im); ?> 复制代码$x = imagesx($im); $y = imagesy($im); echo $x . $y; exit; header("content-type:image/jpeg"); imagejpeg($im); ?> 复制代码方法二获取图片的大小: $imgarr = getimagesize($imgfile); echo "print_r($imgarr); echo "登录后复制"; exit; $im = imagecreatefromjpeg("lyf.jpg"); echo $x . $y; header("content-type:image/jpeg"); imagejpeg($im); ?> 复制代码图片缩放函数: //为了得到大图的宽高 $imgarr = getimagesize($imgfile); $maxw = $imgarr[0]; $maxh = $imgarr[1]; $maxt = $imgarr[2]; $maxm = $imgarr['mime']; //为了把大图变为资源 $im = imagecreatefromjpeg("lyf.jpg"); //小图资源 $minw = 100; $minh = 400; //等比例缩放 if (($minw/$maxw)>($minh/$maxh)) { $rate = $minh/$maxh ;}else{ $rate = $minw / $maxw ; } $minw = floor($maxw * $rate); $minh = floor($maxh * $rate); $minim = imagecreatetruecolor($minw, $minh); //把大图缩放成小图 imagecopyresampled($minim, $im, 0, 0, 0, 0, $minw, $minh, $maxw, $maxh); //小图输出 header("content-type:{$maxm}"); //判断类型 switch ($maxt) { case 1: $imageout = "imagegif"; break; case 2: $imageout = "imagejpeg"; break; case 3: $imageout = "imagepng"; break; } $imageout($minim); $minfilename = "s_".$imgfile; $imageout($minim,$minfilename); // imagejpeg($im); //释放资源 imagedestroy($maxim); imagedestroy($minim); ?> 复制代码图片裁剪函数:imagecopyresampled();图片水印函数:imagecopy();3，裁剪4，水印 $minim = imagecreatefromjpeg("lyf.jpg"); $maxw = imagesx($maxim); $maxh = imagesy($maxim); $minw = imagesx($minim); $minh = imagesy($minim); imagecopy($maxim, $minim, $maxw-$minw, $maxh-$minh, 0, 0, $minw, $minh); header("content-type:image/jpeg"); imagejpeg($mamim); ?> 复制代码