一款php生成验证码实现代码

一款php生成验证码实现代码，把自定义了session的目录，这样就不是php.ini里默认的session文件保存路径了，如下面session_save_path,可重新定义目录。

session_save_path,可重新定义目录。
*/
$sesssavepath = dirname(__file__)."/../data/sessions/";
if(is_writeable($sesssavepath) && is_readable($sesssavepath)){ session_save_path($sesssavepath); }
session_start();
$vstr = '';
for($i=0; $i<4; $i++) $vstr .= chr(mt_rand(65,90));
if(function_exists("imagecreate")){
 $ntime = time();
 if(empty($_session['verifycode_last']) || empty($_session['verifycode']) || ($ntime - $_session['verifycode_last'] > 5)){
  $_session['verifycode'] = strtolower($vstr);
  $_session['verifycode_last'] = $ntime;
 }
 $vstr = $_session['verifycode'];
 $vstrlen = strlen($vstr);
 $img = imagecreate(50,20);
 imagecolorallocate($img, 255,255,255);
 $line1 = imagecolorallocate($img,240,220,180);
 $line2 = imagecolorallocate($img,250,250,170);
 for($j=3;$j<=16;$j=$j+3){
  imageline($img,2,$j,48,$j,$line1);
 }
 for($j=2;$j<52;$j=$j+(mt_rand(3,6))){
  imageline($img,$j,2,$j-6,18,$line2);
 }
 $bordercolor = imagecolorallocate($img, 0x99,0x99,0x99);
 imagerectangle($img, 0, 0, 49, 19, $bordercolor);
 $fontcolor = imagecolorallocate($img, 48,61,50);
 for($i=0;$i<$vstrlen;$i++){
  $bc = mt_rand(0,1);
  $vstr[$i] = strtoupper($vstr[$i]);
  imagestring($img, 5, $i*10+6, mt_rand(2,4), $vstr[$i], $fontcolor);
 }

 header("pragma:no-cachern");
 header("cache-control:no-cachern");
 header("expires:0rn");

 if(function_exists("imagejpeg")){
  header("content-type:image/jpegrn");
  imagejpeg($img);
 }else{
  header("content-type:image/pngrn");
  imagepng($img);
 }
 imagedestroy($img);
 exit();
}

$ico_pic 是你要给图片加水印的水印图片，其它的参数都有详细的说明，如果你下大找这类代码可以下载保存成php文件再利用后面说的调用方法来调用本生成水印图片类代码。

 class smallpic{

  private $src_pic;//原图
  private $ico_pic = "003.png";//水印图
  private $ico_text = "水印";//水印文字
  private $small_width;//缩略图宽度
  private $small_height;//缩略图高度
  private $is_ico_pic = true;//是否加图片水印
  private $is_text = true;//是否加文字水印
  private $src_x = 20;//水印在原图的x坐标
  private $src_y = 20;//水印在原图的y坐标
  private $ut = "utf-8";//文字编码
  private $font_color = "#990000";//文字水印颜色
  private $samll_pic_name = "smallpic";//小图的名称
  private $big_pic_name = "bigpic";//大图的名称

  function __construct($src_pic,$small_width,$small_height){
   $this->checkfile($src_pic);
   $this->checkfile($this->ico_pic);
  $this->src_pic = $src_pic;
  $this->small_width = $small_width;
  $this->small_height = $small_height;
  }

 private function __get($property_name){
  return $this->$property_name;
 }

 private function __set($property_name,$value){
  return $this->$property_name = $value;
 }

 /**
  * 取得图片的一些基本信息，类型为array
  */
  function getimageinfo($image){
  return @getimagesize($image);
  }

 /**
  * 把图片加载到php中
  * $image 传进来的图片
  */
  function getimage($image){
  $image_info = $this->getimageinfo($image);
  switch($image_info[2]){
   case 1:
    $img = @imagecreatefromgif($image);
    break;
   case 2:
    $img = @imagecreatefromjpeg($image);
    break;
   case 3:
    $img = @imagecreatefrompng($image);
    break;
  }
  return $img;
  }

 function createimageforsuffix($big_pic,$new_pic){
  $image_info = $this->getimageinfo($this->src_pic);
  switch($image_info[2]){
   case 1:
    //输出大图
    @imagegif($big_pic,$this->big_pic_name.".gif");
    //输出小图
    @imagegif($new_pic,$this->samll_pic_name.".gif");
    break;
   case 2:
    //输出大图
    @imagejpeg($big_pic,$this->big_pic_name.".jpg");
    //输出小图
    @imagejpeg($new_pic,$this->samll_pic_name.".jpg");
    break;
   case 3:
    //输出大图
    @imagepng($big_pic,$this->big_pic_name.".png");
    //输出小图
    @imagepng($new_pic,$this->samll_pic_name.".png");
    break;
  }
 }

 function checkfile($file){
  if(!file_exists($file)){
   die("图片:".$file."不存在！");
  }
 }

 function createsmallimage(){
  $big_pic = $this->getimage($this->src_pic);
  $big_pic_info = $this->getimageinfo($this->src_pic);
  $new_pic = $this->getimage($this->ico_pic);
  $new_pic_info = $this->getimageinfo($this->ico_pic);
  $rgb = $this->convcolor();

  //判断是按宽比例缩放还是按高比例缩放
  if($big_pic_info[0] > $big_pic_info[1]){
   $ratio = $this->small_width/(int)$big_pic_info[0];
   $small_pic_width = $this->small_width;
   $small_pic_height = (int)($big_pic_info[1]*$ratio);
  }else{
   $ratio = $this->small_height/(int)$big_pic_info[1];
   $small_pic_height = $this->small_height;
   $small_pic_width = (int)($big_pic_info[0]*$ratio);
  }

  //echo $small_pic_width = (int)($big_pic_info[0]*$ratio);
  //echo $small_pic_height = (int)($big_pic_info[1]*$ratio);

  //是否打图片水印
  if ($this->is_ico_pic){
   //打图片水印
   @imagecopy($big_pic,$new_pic,$this->src_x,$this->src_y,0,0,$new_pic_info[0],$new_pic_info[1]);
  }
  //是否打文字水印
  if ($this->is_text){
   //设置文字颜色
   $text_color = @imagecolorallocate($big_pic,$rgb[0],$rgb[1],$rgb[2]);
   //转换文字编码
   $text = @iconv($this->ut,"utf-8",$this->ico_text);
   //打文字水印
   @imagettftext($big_pic,12,0,$this->src_x,$this->src_y,$text_color,"simkai_0.ttf",$text);
  }
  //新建一个新图片的画板
  $new_pic = @imagecreatetruecolor($small_pic_width,$small_pic_height);
  //生成缩略图
  @imagecopyresized($new_pic,$big_pic,0,0,0,0,$small_pic_width,$small_pic_height,$big_pic_info[0],$big_pic_info[1]);
  //输出图
  $this->createimageforsuffix($big_pic,$new_pic);
 }

 /**
  * 类内部的功能函数把#000000转换成255,255,255
  */
 private function convcolor(){
  $rgb = array();
  $color = preg_replace("/#/","",$this->font_color);
  $c = hexdec($color);
  $r = ($c >> 16) & 0xff;
  $g = ($c >> 8) & 0xff;
  $b = $c & 0xff;
  $rgb[0] = $r;
  $rgb[1] = $g;
  $rgb[2] = $b;
  return $rgb;
 }
 }

//调用方法
 

$pic = new smallpic("002.jpg",600,300);
 $pic->is_text = true;
 $pic->is_ico_pic = true;
 $pic->ico_pic = "./images/004.png";
 $pic->ico_text = "新年快乐!";
 //$pic->src_x = 80;
 $pic->src_y = 80;
 $pic->ut = "utf-8";
 $pic->font_color = "#0521f8";
 $pic->samll_pic_name = "hslsamll";
 $pic->big_pic_name = "hslbig";
 $pic->createsmallimage();

?>

1.用imagecreatetruecolor和imagecopyresampled函数分别取代imagecreate和imagecopyresized
2.给imagejpeg的第三个参数带上100(例:imagejpeg($ni,$tofile,100))

imagecreatetruecolor -- 新建一个真彩色图像
说明
resource imagecreatetruecolor ( int x_size, int y_size )
imagecreatetruecolor() 返回一个图像标识符，代表了一幅大小为 x_size 和 y_size 的黑色图像

*/

header ("content-type: image/png");
$im = @imagecreatetruecolor (50, 100)
     or die ("cannot initialize new gd image stream");
$text_color = imagecolorallocate ($im, 233, 14, 91);
imagestring ($im, 1, 5, 5,  "a simple text string", $text_color);
imagepng ($im);
imagedestroy ($im);

/*

如果使用普通的imagecreate()函数将造成图片质量失真的情况，从网上搜了一下解决办法，方法是用imagecreateruecolor()函数替换imagecreate()函数。
*/

function createpreview($img,$name,$path,$maxwidth,$maxheight,$quality){//图片,保存名称,保存路径,最大宽,最大高,质量
 $widthratio=0;
 $heightratio=0;
 $width=imagesx($img);
 $height=imagesy($img);
 //开始计算缩小比例
 if($width>$maxwidth||$height>$maxheight){
  if($width>$maxwidth){
   $widthratio=$maxwidth/$width;
  }
  if($height>$maxheight){
   $heightratio=$maxheight/$height;
  }
  if($widthratio>0&&$heightratio>0){
   if($widthratio<$heightratio){
    $ratio=$widthratio;
   }else{
    $ratio=$heightratio;
   }
  }elseif($widthratio>0){
   $ratio=$widthratio;
  }elseif($heightratio>0){
   $ratio=$heightratio;
  }
  //根据得出的比例,重新计算缩略图的宽和高
  $newwidth=$ratio*$width;
  $newheight=$ratio*$height;
  $newimg=imagecreatetruecolor($newwidth,$newheight); // 创建目标图
  imagecopyresized($newimg,$img,0,0,0,0,$newwidth,$newheight,$width,$height);
  imagejpeg($newimg,$path."s_".$name,$quality);
  imagedestroy($newimg);
 }else{
  imagejpeg($img,$path."s_".$name,$quality);
 }
}
/*

imagecopyresamples() ,其像素插值算法得到的图像边缘比较平滑.质量较好(但该函数的速度比 imagecopyresized() 慢).

在php中给图片增加水印有imagecreatefromjpeg imagecreatefrompng imagecopymerge imagejpeg就成了，只要你设置原图与水印图片就成了，下面看实例。
*/

代码如下	复制代码
header("content-type: image/jpeg"); $filename='temp/www.111cn.net/111cn.net.jpg'; $im=imagecreatefromjpeg($filename); $s=imagecreatefrompng('mb.111cn.net/pic/water_template.png'); imagecopymerge($im,$s,0,200,0,0,365,27,20); imagejpeg($im);

本文章提供这款图片处理类，他可以做的事情有把图片生成缩略图,可能给图片增加水印以及获取图片信息，算是比较实用代码又简洁的函数*/

代码如下

复制代码

class image {  public $info=array();  function __construct()  {   !extension_loaded('gd') && exit("www.111cn.net提示：服务器环境不支持gd库");   return true;  }  function image()  {   $this->__construct();  }    function thumb($image,$thumb_width=300,$thumb_height=225)  {   $info=$this->info($image);   $scale=min(1,min($thumb_width/$info['width'],$thumb_height/$info['height'])); //按比例缩放   $thumb_width=intval($info['width']*$scale);   $thumb_height=intval($info['height']*$scale);   $createfunc='imagecreatefrom'.($info['type']=='jpg'?'jpeg':$info['type']);   $im=$createfunc($image);   $thumb_im=$info['type']!='gif' && function_exists('imagecreatetruecolor')?imagecreatetruecolor($thumb_width,$thumb_height):imagecreate($thumb_width,$thumb_height);   imagecopyresampled($thumb_im,$im,0,0,0,0,$thumb_width,$thumb_height,$info['width'],$info['height']);   if($info['type']=='gif' || $info['type']=='png')   {    $bgcolor=imagecolorallocate($thumb_im,0,255,0);    imagecolortransparent($thumb_im,$bgcolor);   }   $imagefunc='image'.($info['type']=='jpg'?'jpeg':$info['type']);   $thumbname='thumb_'.$info['name'].'.'.$info['type'];   $imagefunc($thumb_im,$info['path'].$thumbname);   imagedestroy($im);   imagedestroy($thumb_im);   return $info['path'].$thumbname;    }  function watermark($image,$pos=9,$watermarkimg='images/watermark.gif',$pct=65,$text='',$w_font=5,$w_color='#ff0000')  {   $imageinfo=$this->info($image);   $source_w=$imageinfo['width'];   $source_h=$imageinfo['height'];   $imagecreatefunc='imagecreatefrom'.($imageinfo['type']=='jpg'?'jpeg':$imageinfo['type']);   $im=$imagecreatefunc($image);   if(!empty($watermarkimg) && file_exists($watermarkimg)) //添加图片水印   {    $iswaterimage=true;    $watermarkinfo=$this->info($watermarkimg);    $width=$watermarkinfo['width'];    $height=$watermarkinfo['height'];    $watermarkcreatefunc='imagecreatefrom'.($watermarkinfo['type']=='jpg'?'jpeg':$watermarkinfo['type']);    $watermark_im=$watermarkcreatefunc($watermarkimg);   }   else //添加文字水印   {    $iswaterimage=false;    if(!empty($w_color) && strlen($w_color)==7)    {     $r=hexdec(substr($w_color,1,2));     $g=hexdec(substr($w_color,3,2));     $b=hexdec(substr($w_color,5,2));    }    $temp = imagettfbbox(ceil($w_font*2.5), 0, 'fonts/alger.ttf', $text);    $width = $temp[2] - $temp[6];    $height = $temp[3] - $temp[7];    unset($temp);   }   switch($pos)   {    case 0:     $wx = mt_rand(0,($source_w - $width));     $wy = mt_rand(0,($source_h - $height));     break;    case 1:     $wx = 5;     $wy = 5;     break;    case 2:     $wx = ($source_w - $width) / 2;     $wy = 5;     break;    case 3:     $wx = $source_w - $width-5;     $wy = 5;     break;    case 4:     $wx = 5;     $wy = ($source_h - $height) / 2;     break;    case 5:     $wx = ($source_w - $width) / 2;     $wy = ($source_h - $height) / 2;     break;    case 6:     $wx = $source_w - $width-5;     $wy = ($source_h - $height) / 2;     break;    case 7:     $wx = 5;     $wy = $source_h - $height-5;     break;    case 8:     $wx = ($source_w - $width) / 2;     $wy = $source_h - $height-5;     break;    default:     $wx = $source_w - $width-5;     $wy = $source_h - $height-5;     break;   }   if($iswaterimage)   {    if($imageinfo['type'] == 'png') {     imagecopy($im, $watermark_im, $wx, $wy, 0, 0, $width, $height);    } else {     imagecopymerge($im, $watermark_im, $wx, $wy, 0, 0, $width, $height, $pct);    }   }   else   {    imagestring($im,$w_font,$wx,$wy,$text,imagecolorallocate($im,$r,$g,$b));   }   $imagefunc='image'.($imageinfo['type']=='jpg'?'jpeg':$imageinfo['type']);   $imagefunc($im,$image);   imagedestroy($im);   return true;  }  function info($image)  {   $info=array();   $info['size']=filesize($image);   $imageinfo=getimagesize($image);   $info['width']=$imageinfo[0];   $info['height']=$imageinfo[1];   $info['width_height']=$imageinfo[3];   $info['mime']=$imageinfo['mime'];   unset($imageinfo);   $imageinfo=pathinfo($image);   $info['path']=$imageinfo['dirname'].'/';   $info['type']=strtolower($imageinfo['extension']); //图片类型，不含'.'   $info['name']=$imageinfo['filename'];   unset($imageinfo,$name);   $this->info=$info;   return $info;  } }