PHP uses the Gifencoder class to generate the GIF dynamic picture verification Code _php instance

I believe many people have thought how to use PHP to generate GIF animation to achieve dynamic picture verification code, the following is the implementation process.
Imagecode function through the Gifencoder class implementation of the GIF animated PHP source code, interested friends can study.

Effect
Copy CodeThe code is as follows:
/**

* Imagecode generate GIF picture verification

* @param $string string

* @param $width width

* @param $height Height

* */

function Imagecode ($string = ", $width = $height = 25)

{

$authstr = $string? $string: ((Time ()% 2 = = 0)? Mt_rand (9999): Mt_rand (10000, 99999));

$board _width = $width;

$board _height = $height;

Generate a 32-frame GIF animation

for ($i = 0; $i < $i + +)

{

Ob_start ();

$image = Imagecreate ($board _width, $board _height);

Imagecolorallocate ($image, 0,0,0);

Set Text color array

$colorList [] = Imagecolorallocate ($image, 15,73,210);

$colorList [] = Imagecolorallocate ($image, 0,64,0);

$colorList [] = Imagecolorallocate ($image, 0,0,64);

$colorList [] = Imagecolorallocate ($image, 0,128,128);

$colorList [] = Imagecolorallocate ($image, 27,52,47);

$colorList [] = Imagecolorallocate ($image, 51,0,102);

$colorList [] = Imagecolorallocate ($image, 0,0,145);

$colorList [] = Imagecolorallocate ($image, 0,0,113);

$colorList [] = Imagecolorallocate ($image, 0,51,51);

$colorList [] = Imagecolorallocate ($image, 158,180,35);

$colorList [] = Imagecolorallocate ($image, 59,59,59);

$colorList [] = Imagecolorallocate ($image, 0,0,0);

$colorList [] = Imagecolorallocate ($image, 1,128,180);

$colorList [] = Imagecolorallocate ($image, 0,153,51);

$colorList [] = Imagecolorallocate ($image, 60,131,1);

$colorList [] = Imagecolorallocate ($image, 0,0,0);

$fontcolor = Imagecolorallocate ($image, 0,0,0);

$gray = Imagecolorallocate ($image, 245,245,245);

$color = Imagecolorallocate ($image, 255,255,255);

$color 2 = imagecolorallocate ($image, 255,0,0);

Imagefill ($image, 0, 0, $gray);

$space = 15; Character Spacing

if ($i > 0)//Shield First frame

{

for ($k = 0; $k < strlen ($AUTHSTR); $k + +)

{

$colorRandom = Mt_rand (0,sizeof ($colorList)-1);

$float _top = rand (0,4);

$float _left = rand (0,3);

Imagestring ($image, 6, $space * $k, $top + $float _top, substr ($authstr, $k, 1), $colorList [$colorRandom]);

}

}

for ($k = 0; $k < $k + +)

{

$colorRandom = Mt_rand (0,sizeof ($colorList)-1);

Imagesetpixel ($image, Rand ()%70, Rand ()%15, $colorList [$colorRandom]);

}

Adding interference lines

for ($k = 0; $k < 3; $k + +)

{

$colorRandom = Mt_rand (0, sizeof ($colorList)-1);

$todrawline = rand (0,1);

$todrawline = 1;

if ($todrawline)

{

Imageline ($image, Mt_rand (0, $board _width), Mt_rand (0, $board _height), Mt_rand (0, $board _width), Mt_rand (0, $board _ height), $colorList [$colorRandom]);

}

Else

{

$w = Mt_rand (0, $board _width);

$h = Mt_rand (0, $board _width);

Imagearc ($image, $board _width-floor ($w/2), Floor ($h/2), $w, $h, Rand (90,180), Rand (180,270), $colorList [$colorRando M]);

}

}

Imagegif ($image);

Imagedestroy ($image);

$imagedata [] = Ob_get_contents ();

Ob_clean ();

+ + $i;

}

$gif = new Gifencoder ($imagedata);

Header (' content-type:image/gif ');

echo $gif->getanimation ();

}

Gifencoder class Source:
Copy CodeThe code is as follows:
<?php
Class Gifencoder {
var $GIF = "gif89a"; /* GIF Header 6 bytes */
var $VER = "Gifencoder V2.06"; /* Encoder version */
var $BUF = Array ();
var $LOP = 0;
var $DIS = 2;
var $COL =-1;
var $IMG =-1;
var $ERR = Array (
' ERR00 ' = ' Does not supported function for only one image! ',
' ERR01 ' = ' Source is not a GIF image! ',
' ERR02 ' = ' unintelligible flag ',
' ERR03 ' = ' Could not make animation from animated GIF source ',
);
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: Gifencoder ...
::
*/
function Gifencoder (
$GIF _src, $GIF _dly, $GIF _lop, $GIF _dis,
$GIF _red, $GIF _grn, $GIF _blu, $GIF _mod
) {
if (! Is_array ($GIF _src) &&! Is_array ($GIF _tim)) {
printf ("%s:%s", $this->ver, $this->err [' ERR00 ']);
Exit (0);
}
$this->lop = ($GIF _lop >-1)? $GIF _lop:0;
$this->dis = ($GIF _dis >-1)? (($GIF _dis < 3) $GIF _dis:3): 2;
$this->col = ($GIF _red > 1 && $GIF _grn > 1 && $GIF _blu >-1)?
($GIF _red | ($GIF _grn << 8) | ($GIF _blu << 16)) :-1;
for ($i = 0; $i < count ($GIF _src); $i + +) {
if (Strtolower ($GIF _mod) = = "url") {
$this->buf [] = Fread (fopen ($GIF _src [$i], "RB"), FileSize ($GIF _src [$i]));
}
else if (Strtolower ($GIF _mod) = = "Bin") {
$this->buf [] = $GIF _src [$i];
}
else {
printf ("%s:%s (%s)!", $this->ver, $this->err [' ERR02 '], $GIF _mod);
Exit (0);
}
if (substr ($this->buf [$i], 0, 6)! = "gif87a" && substr ($this->buf [$i], 0, 6)! = "gif89a") {
printf ("%s:%d%s", $this->ver, $i, $this->err [' ERR01 ']);
Exit (0);
}
for ($j = (3 * (2 << (ord ($this->buf [$i] {ten}) & 0x07)), $k = TRUE; $k; $j + +) {
Switch ($this->buf [$i] {$j}) {
Case "!":
if ((substr ($this->buf [$i], ($j + 3), 8)) = = "NETSCAPE") {
printf ("%s:%s (%s source)!", $this->ver, $this->err [' ERR03 '], ($i + 1));
Exit (0);
}
Break
Case ";":
$k = FALSE;
Break
}
}
}
Gifencoder::gifaddheader ();
for ($i = 0; $i < count ($this->buf); $i + +) {
Gifencoder::gifaddframes ($i, $GIF _dly [$i]);
}
Gifencoder::gifaddfooter ();
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: Gifaddheader ...
::
*/
function Gifaddheader () {
$cmap = 0;
if (Ord ($this->buf [0] {ten}) & 0x80) {
$cmap = 3 * (2 << (ord ($this->buf [0] {ten}) & 0x07));
$this->gif. = substr ($this->buf [0], 6, 7);
$this->gif. = substr ($this->buf [0], $cmap);
$this->gif. = "!/377/13NETSCAPE2.0/3/1". Gifencoder::gifword ($this->lop). "/0";
}
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: Gifaddframes ...
::
*/
function Gifaddframes ($i, $d) {
$Locals _STR = 3 * (2 << (ord ($this->buf [$i] {ten}) & 0x07);
$Locals _end = strlen ($this->buf [$i])-$Locals _str-1;
$Locals _tmp = substr ($this->buf [$i], $Locals _str, $Locals _end);
$Global _len = 2 << (ord ($this->buf [0] {ten}) & 0x07);
$Locals _len = 2 << (ord ($this->buf [$i] {ten}) & 0x07);
$Global _rgb = substr ($this->buf [0], 13,
3 * (2 << (ord ($this->buf [0] {ten}) & 0x07));
$Locals _rgb = substr ($this->buf [$i], 13,
3 * (2 << (ord ($this->buf [$i] {ten}) & 0x07));
$Locals _ext = "!/xf9/x04". Chr (($this->dis << 2) + 0).
Chr (($d >> 0) & 0xFF). Chr (($d >> 8) & 0xFF). "/x0/x0";
if ($this->col >-1 && ord ($this->buf [$i] {ten}) & 0x80) {
for ($j = 0; $j < (2 << (ord ($this->buf [$i] {ten}) & 0x07), $j + +) {
if (
Ord ($Locals _rgb {3 * $j + 0}) = = ($this->col >> 0) & 0xFF &
Ord ($Locals _rgb {3 * $j + 1}) = = ($this->col >> 8) & 0xFF &
Ord ($Locals _rgb {3 * $j + 2}) = = ($this->col >>) & 0xFF
) {
$Locals _ext = "!/xf9/x04". Chr (($this->dis << 2) + 1).
Chr (($d >> 0) & 0xFF). Chr (($d >> 8) & 0xFF). Chr ($j). "/x0";
Break
}
}
}
Switch ($Locals _tmp {0}) {
Case "!":
$Locals _img = substr ($Locals _tmp, 8, 10);
$Locals _tmp = substr ($Locals _tmp, strlen ($Locals _tmp)-18);
Break
Case ",":
$Locals _img = substr ($Locals _tmp, 0, 10);
$Locals _tmp = substr ($Locals _tmp, ten, strlen ($Locals _tmp)-10);
Break
}
if (Ord ($this->buf [$i] {ten}) & 0x80 && $this->img >-1) {
if ($Global _len = = $Locals _len) {
if (Gifencoder::gifblockcompare ($Global _rgb, $Locals _rgb, $Global _len)) {
$this->gif. = ($Locals _ext. $Locals _img. $Locals _tmp);
}
else {
$byte = Ord ($Locals _img {9});
$byte |= 0x80;
$byte &= 0xF8;
$byte |= (Ord ($this->buf [0] {ten}) & 0x07);
$Locals _img {9} = Chr ($byte);
$this->gif. = ($Locals _ext. $Locals _img $Locals _rgb. $Locals _tmp);
}
}
else {
$byte = Ord ($Locals _img {9});
$byte |= 0x80;
$byte &= 0xF8;
$byte |= (Ord ($this->buf [$i] {ten}) & 0x07);
$Locals _img {9} = Chr ($byte);
$this->gif. = ($Locals _ext. $Locals _img $Locals _rgb. $Locals _tmp);
}
}
else {
$this->gif. = ($Locals _ext. $Locals _img. $Locals _tmp);
}
$this->img = 1;
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: Gifaddfooter ...
::
*/
function Gifaddfooter () {
$this->gif. = ";";
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: Gifblockcompare ...
::
*/
function Gifblockcompare ($GlobalBlock, $LocalBlock, $Len) {
for ($i = 0; $i < $Len; $i + +) {
if (
$GlobalBlock {3 * $i + 0}! = $LocalBlock {3 * $i + 0} | |
$GlobalBlock {3 * $i + 1}! = $LocalBlock {3 * $i + 1} | |
$GlobalBlock {3 * $i + 2}! = $LocalBlock {3 * $i + 2}
) {
return (0);
}
}
return (1);
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: Gifword ...
::
*/
function Gifword ($int) {
Return (Chr ($int & 0xFF). Chr (($int >> 8) & 0xFF));
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: Getanimation ...
::
*/
function Getanimation () {
Return ($this->gif);
}
}
?>

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