<?php
/*
Dynamic Heading Generator
By Stewart Rosenberger
http://www.stewartspeak.com/headings/
This script generates PNG images of text, written in
the font/size that you specify. These PNG images are passed
back to the browser. Optionally, they can be cached for later use.
If a cached image is found, a new image will not be generated,
and the existing copy will be sent to the browser.
Additional documentation on PHP's image handling capabilities can
be found at http://www.php.net/image/
*/
$font_file = 'ARIAL.TTF' ;
$font_size = 12 ;
$font_color = '#000000' ;
$background_color = '#ffffff' ;
$transparent_background = true ;
$cache_images = true ;
$cache_folder = 'cache' ;
/*
---------------------------------------------------------------------------
For basic usage, you should not need to edit anything below this comment.
If you need to further customize this script's abilities, make sure you
are familiar with PHP and its image handling capabilities.
---------------------------------------------------------------------------
*/
$mime_type = 'image/png' ;
$extension = '.png' ;
$send_buffer_size = 4096 ;
// check for GD support
if(!function_exists('ImageCreate'))
fatal_error('Error: Server does not support PHP image generation') ;
// clean up text
if(empty($_GET['text']))
fatal_error('Error: No text specified.') ;
$text = $_GET['text'] ;
if(get_magic_quotes_gpc())
$text = stripslashes($text) ;
$text = javascript_to_html($text) ;
// look for cached copy, send if it exists
$hash = md5(basename($font_file) . $font_size . $font_color .
$background_color . $transparent_background . $text) ;
$cache_filename = $cache_folder . '/' . $hash . $extension ;
if($cache_images && ($file = @fopen($cache_filename,'rb')))
{
header('Content-type: ' . $mime_type) ;
while(!feof($file))
print(($buffer = fread($file,$send_buffer_size))) ;
fclose($file) ;
exit ;
}
// check font availability
$font_found = is_readable($font_file) ;
if(!$font_found)
{
fatal_error('Error: The server is missing the specified font.') ;
}
// create image
$background_rgb = hex_to_rgb($background_color) ;
$font_rgb = hex_to_rgb($font_color) ;
$dip = get_dip($font_file,$font_size) ;
$box = @ImageTTFBBox($font_size,0,$font_file,$text) ;
$image = @ImageCreate(abs($box[2]-$box[0]),abs($box[5]-$dip)) ;
/*if(!$image || !$box)
{
fatal_error('Error: The server could not create this heading image.') ;
}*/
// allocate colors and draw text
$background_color = @ImageColorAllocate($image,$background_rgb['red'],
$background_rgb['green'],$background_rgb['blue']) ;
$font_color = ImageColorAllocate($image,$font_rgb['red'],
$font_rgb['green'],$font_rgb['blue']) ;
ImageTTFText($image,$font_size,0,-$box[0],abs($box[5]-$box[3])-$box[1],
$font_color,$font_file,$text) ;
// set transparency
if($transparent_background)
ImageColorTransparent($image,$background_color) ;
header('Content-type: ' . $mime_type) ;
ImagePNG($image) ;
// save copy of image for cache
if($cache_images)
{
@ImagePNG($image,$cache_filename) ;
}
ImageDestroy($image) ;
exit ;
/*
try to determine the "dip" (pixels dropped below baseline) of this
font for this size.
*/
function get_dip($font,$size)
{
$test_chars = 'abcdefghijklmnopqrstuvwxyz' .
'ABCDEFGHIJKLMNOPQRSTUVWXYZ' .
'1234567890' .
'!@#$%^&*()\'"\\/;.,`~<>[]{}-+_-=' ;
$box = @ImageTTFBBox($size,0,$font,$test_chars) ;
return $box[3] ;
}
/*
attempt to create an image containing the error message given.
if this works, the image is sent to the browser. if not, an error
is logged, and passed back to the browser as a 500 code instead.
*/
function fatal_error($message)
{
// send an image
if(function_exists('ImageCreate'))
{
$width = ImageFontWidth(5) * strlen($message) + 10 ;
$height = ImageFontHeight(5) + 10 ;
if($image = ImageCreate($width,$height))
{
$background = ImageColorAllocate($image,255,255,255) ;
$text_color = ImageColorAllocate($image,0,0,0) ;
ImageString($image,5,5,5,$message,$text_color) ;
header('Content-type: image/png') ;
ImagePNG($image) ;
ImageDestroy($image) ;
exit ;
}
}
// send 500 code
header("HTTP/1.0 500 Internal Server Error") ;
print($message) ;
exit ;
}
/*
decode an HTML hex-code into an array of R,G, and B values.
accepts these formats: (case insensitive) #ffffff, ffffff, #fff, fff
*/
function hex_to_rgb($hex)
{
// remove '#'
if(substr($hex,0,1) == '#')
$hex = substr($hex,1) ;
// expand short form ('fff') color
if(strlen($hex) == 3)
{
$hex = substr($hex,0,1) . substr($hex,0,1) .
substr($hex,1,1) . substr($hex,1,1) .
substr($hex,2,1) . substr($hex,2,1) ;
}
if(strlen($hex) != 6)
fatal_error('Error: Invalid color "'.$hex.'"') ;
// convert
$rgb['red'] = hexdec(substr($hex,0,2)) ;
$rgb['green'] = hexdec(substr($hex,2,2)) ;
$rgb['blue'] = hexdec(substr($hex,4,2)) ;
return $rgb ;
}
/*
convert embedded, javascript unicode characters into embedded HTML
entities. (e.g. '%u2018' => '‘'). returns the converted string.
*/
function javascript_to_html($text)
{
$matches = null ;
preg_match_all('/%u([0-9A-F]{4})/i',$text,$matches) ;
if(!empty($matches)) for($i=0;$i<sizeof($matches[0]);$i++)
$text = str_replace($matches[0][$i],
'&#'.hexdec($matches[1][$i]).';',$text) ;
return $text ;
}
?>That's my code. I get these errors:
Warning: imagecolorallocate(): supplied argument is not a valid Image resource in /var/www/ripgm/images/email.php on line 92
Warning: imagettftext() expects parameter 1 to be resource, boolean given in /var/www/ripgm/images/email.php on line 94
Warning: imagecolortransparent(): supplied argument is not a valid Image resource in /var/www/ripgm/images/email.php on line 98
Warning: Cannot modify header information - headers already sent by (output started at /var/www/ripgm/images/email.php:92) in /var/www/ripgm/images/email.php on line 100
Warning: imagepng(): supplied argument is not a valid Image resource in /var/www/ripgm/images/email.php on line 101
Warning: imagedestroy(): supplied argument is not a valid Image resource in /var/www/ripgm/images/email.php on line 109
Can anyone see any issues here?
