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.