"PHP Programming Fastest understand" seventh: PHP picture verification code and thumbnail

Example 22 core code for image validation
Copy CodeThe code is as follows:
<?php
Header ("Content-type:image/png");
$num = ' 1234 ';
$imagewidth = 60;
$imageheight = 18;

$numimage = Imagecreate ($imagewidth, $imageheight);
Imagecolorallocate ($numimage, 240,240,240);
for ($i =0; $i <strlen ($num); $i + +) {
$x = Mt_rand (1,8) + $imagewidth * $i/4;
$y = Mt_rand (1, $imageheight/4);
$color =imagecolorallocate ($numimage, Mt_rand (0,150), Mt_rand (0,150), Mt_rand (0,150));
Imagestring ($numimage, 5, $x, $y, $num [$i], $color);
}

For ($i =0 $i <200; $i + +) {
$randcolor =imagecolorallocate ($numimage, Rand (200,255), Rand (200,255), Rand (200,255));
Imagesetpixel ($numimage, Rand ()%70,rand ()%20, $randcolor);
}
Imagepng ($numimage);
Imagedestroy ($numimage);
?>

This is the output of 4 authentication code example, for Chinese characters, need font file and Imagettftext function, when you use the Internet search it. You have to generate random numbers, there are mt_rand functions, you have to use the session to save the random number, if you need to turn to utf-8, you need the ICONV function.

instance 23 thumbnail
Copy CodeThe code is as follows:
<?php
Class SimpleImage {
var $image;
var $image _type;
function Load ($filename) {
$image _info = getimagesize ($filename);
$this->image_type = $image _info[2];
if ($this->image_type = = imagetype_jpeg) {
$this->image = Imagecreatefromjpeg ($filename);
} elseif ($this->image_type = = imagetype_gif) {
$this->image = imagecreatefromgif ($filename);
} elseif ($this->image_type = = imagetype_png) {
$this->image = imagecreatefrompng ($filename);
}
}
function Save ($filename, $image _type=imagetype_jpeg, $compression =75, $permissions =null) {
if ($image _type = = imagetype_jpeg) {
Imagejpeg ($this->image, $filename, $compression);
} elseif ($image _type = = imagetype_gif) {
Imagegif ($this->image, $filename);
} elseif ($image _type = = imagetype_png) {
Imagepng ($this->image, $filename);
}
if ($permissions!= null) {
chmod ($filename, $permissions);
}
}
function output ($image _type=imagetype_jpeg) {
if ($image _type = = imagetype_jpeg) {
Imagejpeg ($this->image);
} elseif ($image _type = = imagetype_gif) {
Imagegif ($this->image);
} elseif ($image _type = = imagetype_png) {
Imagepng ($this->image);
}
}
function GetWidth () {
Return Imagesx ($this->image);
}
function GetHeight () {
Return Imagesy ($this->image);
}
function Resizetoheight ($height) {
$ratio = $height/$this->getheight ();
$width = $this->getwidth () * $ratio;
$this->resize ($width, $height);
}
function Resizetowidth ($width) {
$ratio = $width/$this->getwidth ();
$height = $this->getheight () * $ratio;
$this->resize ($width, $height);
}
function scale ($scale) {
$width = $this->getwidth () * $scale/100;
$height = $this->getheight () * $scale/100;
$this->resize ($width, $height);
}
function Resize ($width, $height) {
$new _image = Imagecreatetruecolor ($width, $height);
Imagecopyresampled ($new _image, $this->image, 0, 0, 0, 0, $width, $height, $this->getwidth (), $this->getheight ( ));
$this->image = $new _image;
}
}

$newfile = Upload_dir. " /icons/". MD5 ($_session[' USER ']->email)." JPG "//Upload file saved directory
$image = new SimpleImage ();
$image->load ($_files[' icons '] [' tmp_name '])/temporary file name uploaded
$image->resizetowidth (80); Set width
$image->save ($newfile);
?>