PHP function imagettftext() and unicode

Question

I\'m using the PHP function imagettftext() to convert text into a GIF image. The text I am converting has Unicode characters including Japanese. Everything works fine on my

Answer 1

Here's the solution that finally worked for me:

$text = "你好";
// Convert UTF-8 string to HTML entities
$text = mb_convert_encoding($text, 'HTML-ENTITIES',"UTF-8");
// Convert HTML entities into ISO-8859-1
$text = html_entity_decode($text,ENT_NOQUOTES, "ISO-8859-1");
// Convert characters > 127 into their hexidecimal equivalents
$out = "";
for($i = 0; $i < strlen($text); $i++) {
    $letter = $text[$i];
    $num = ord($letter);
    if($num>127) {
      $out .= "&#$num;";
    } else {
      $out .=  $letter;
    }
}

Converting the string to HTML entities works except that the function imagettftext() doesn't accept named entities. For example,

日本語

is OK, but

ç

is not. Converting back to ISO-8859-1, converts the named entities back to characters, but there is a second problem. imagettftext() doesn't support characters with a value greater than >127. The final for-loop encodes these characters in hexadecimal. This solution is working for me with the text that I am using (includes Japanese, Chinese and accented latin characters for Portuguese), but I'm not 100% sure it will work in all cases.

All of these gymnastics are needed because imagettftext() doesn't really accept UTF-8 strings on my server.

Answer 2

Does that particular font file exist on your production machine? If using FTP to upload your files, are you using binary encoding?

Answer 3

My prime suspect is the font you are using for rendering.

According to http://fr3.php.net/imagettftext, different versions of the GD library used by php can show different behaviour.

• GD Version on your local machine: 2.0 or higher
• GD Version on your webhost server: bundled (2.0.34 compatible)

Edit: Another idea: can you verify that $text = '日本語'; is really saved like this on your production server? Maybe there is an encoding problem with your script.

Next edit: BKB already proposed that. So in case this is the cause: he was first with the answer ;-)

Answer 4

I have been having the same problem with a script that will render text in an image and output it. Problem was, that due to different browsers (or code hardiness/paranoia, whichever way you want to think of it), I had no way of knowing what encoding was being put inside the $_GET array.

Here is how I solved the problem.

$item_text = $_GET['text'];

# detect if the string was passed in as unicode
$text_encoding = mb_detect_encoding($item_text, 'UTF-8, ISO-8859-1');
# make sure it's in unicode
if ($text_encoding != 'UTF-8') {
    $item_text = mb_convert_encoding($item_text, 'UTF-8', $text_encoding);
}

# html numerically-escape everything (&#[dec];)
$item_text = mb_encode_numericentity($item_text,
    array (0x0, 0xffff, 0, 0xffff), 'UTF-8');

This solves any problem with imagettftext not being able to handle characters above #127 by simply changing ALL the characters (including multibyte Unicode characters) into their HTML numeric character entity—"A" for "A", "B" for "B", etc.—which the manual page claims support for.

Answer 5

I had the same problem. Converting font from otf to ttf helped. You can use FontForge (available in standard repository) to convert.