Captcha image not showing - php

Question

Ok...so...i'm trying the create my own Captcha to use on a webpage i'm working on.
Since i'm pretty much a noob on php i followed a youtube guide
i followed EVERY SINGLE STEP in this video, everything he did i did too, i dowloaded the same image lybrary(AnonymousClippings.tff btw) and etc BUT for some reason my captcha image is not showing.
I have to files, one for the captcha and one for the index(to call the image function so i can see the image) and use it in a form.
i'm sure the reason for not showing the image is pretty stupid but i just can't figure what's the problem.
if you know a easier way to create my own captcha i would apreciate.
captcha.php
<?php
class captcha{
private static $captcha = "__captcha__";
private static $font;
private static $width = 70;
private static $height = 70;
private static $font_size = 40;
private static $character_width = 40;
private static function session_start(){
if(!isset($_SESSION)){
session_start();
}
}
private static function set_font(){
self::$font = self::$captcha;
$AnonymousClippings = "HERE GOES ALL POSSIBLE CAHRS THAT THE CAPTCHA WILL BE ABLE TO SHOW FROM AnonymousClippings LYBRARY";
$handle = fopen(self::$font,"w+");
fwrite($handle, base64_encode($AnonymousClippings));
fclose($handle);
return self::$font;
}
public static function get_random(){
$type = rand(0,2);
switch ($type){
case 2:
$random = chr(rand(65, 90));
break;
case 1:
$random = chr(rand(97, 122));
break;
default:
$random = chr(rand(0,9));
break;
}
return $random;
}
private static function get_width(){
return self::$width;
}
private static function get_height(){
return self::$height;
}
private static function generate_code($length){
self::session_start();
$code=null;
for($i=0;$i<$length;$i++){
$code.=self::get_random();
}
$_SESSION[self::$captcha] = $code;
self::$width = $length * self::$character_width;
return $code;
}
public static function image(){
$length = 6;
$code = self::generate_code($length);
self::set_font();
ob_start();
$image = imagecreatetruecolor(self::get_width(),self::get_height());
$white = imagecolorallocate($image, 255, 255, 255);
imagefilledrectangle($image, 0, 0, self::get_width(), self::get_height(), $white);
for($dot=0;$dot<2000;$dot++){
$red = rand(0,255);
$green = rand(0,255);
$blue = rand(0,255);
$dot_color = imagecolorallocate($image, $red, $green, $blue);
$x1 = rand(0,self::get_width());
$y1= rand(0,self::get_height());
$x2 = $x1 +1;
$y2 = $y1 +1;
imageline($image, $x1, $y1, $x2, $y2, $dot_color);
}
for($start = $length*(-1); $start<0; $start++){
$color = imagecolorallocate($image, rand(0,177), rand(0,177), rand(0,177));
$character = substr($code, $start,1);
$x =($start+6)*self::$character_width;
$y = rand(self::get_height()-20, self::get_height() -10);
imagettftext($image, self::$font_size, 0, $x, $y, $color, self::$font, $character);
}
imagepng($image);
imagedestroy($image);
$source = ob_get_contents();
ob_end_clean();
unlink(self::$font);
return "data:image/png;base64,".base64_encode($source);
}
public static function get_code(){
self::session_start();
return $_SESSION[self::$captcha];
}
}
?>
index1.php
<?php
require_once("captcha.php");
if(isset($_POST["code"])){
if($_POST["code"]== captcha::get_code()){
echo "good";
}else{
echo "wrong";
}
}
?>
<form method="post">
<img src=" <?php captcha::image() ?>"/><br>
<input type="text" name="code"/><br>
<input type="submit" value="Check"/>
</form>

Answer 1

The methods end up returning the data but you never echo the output.
return "data:image/png;base64,".base64_encode($source);
Partially solved:
<img src="<?php echo captcha::image(); ?>"/><br>
Taken from the comments, next error is font path:
self::$font = self::$captcha;
Don't set em to the same value. $font must point to a font path (like ./arial.ttf).