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php tutorial image processing class (generate thumbnails, add watermarks, obtain image information)
This article provides this image processing class. What it can do is generate thumbnails of images, add watermarks to images, and obtain image information. It is a relatively practical and concise function*/
class image
{
public $info=array();function __construct()
{
!extension_loaded('gd') && exit("www.bKjia.c0m prompt: The server environment does not support the gd library");
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'])); //Scale proportionally
$thumb_width=intval($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']); //Image type, excluding '.'
$info['name']=$imageinfo['filename'];
unset($imageinfo,$name);
$this->info=$info;
Return $info;
}
}