На поведінку цих функцій випливають налаштування в php.ini.
  Exif supports automatically conversion for Unicode and JIS 
  character encodings of user comments when module
  mbstring
  is available. This is done by first decoding the comment
  using the specified characterset. The result is then encoded
  with another characterset which should match your
  HTTP output.
 
| Назва | Початково | Де можна змінювати | Журнал змін | 
|---|---|---|---|
| exif.encode_unicode | "ISO-8859-15" | INI_ALL | |
| exif.decode_unicode_motorola | "UCS-2BE" | INI_ALL | |
| exif.decode_unicode_intel | "UCS-2LE" | INI_ALL | |
| exif.encode_jis | "" | INI_ALL | |
| exif.decode_jis_motorola | "JIS" | INI_ALL | |
| exif.decode_jis_intel | "JIS" | INI_ALL | 
Тут є коротке пояснення директив конфігурації.
exif.encode_unicode
     string
    
     exif.encode_unicode defines the 
     characterset UNICODE user comments are handled.
     This defaults to ISO-8859-15 which should work for
     most non Asian countries. The setting can be empty
     or must be an encoding supported by mbstring. If it
     is empty the current internal encoding of mbstring is
     used.
    
exif.decode_unicode_motorola
     string
    
      exif.decode_unicode_motorola defines 
      the image internal characterset for Unicode encoded user 
      comments if image is in motorola byte order (big-endian).
      This setting cannot be empty but you can specify a list
      of encodings supported by mbstring. The default is UCS-2BE.
     
exif.decode_unicode_intel
     string
    
      exif.decode_unicode_intel defines 
      the image internal characterset for Unicode encoded user 
      comments if image is in intel byte order (little-endian).
      This setting cannot be empty but you can specify a list
      of encodings supported by mbstring. The default is UCS-2LE.
     
exif.encode_jis
     string
    
      exif.encode_jis defines the 
      characterset JIS user comments are handled.
      This defaults to an empty value which forces 
      the functions to use the current internal encoding
      of mbstring.
     
exif.decode_jis_motorola
     string
    
      exif.decode_jis_motorola defines 
      the image internal characterset for JIS encoded user 
      comments if image is in motorola byte order (big-endian).
      This setting cannot be empty but you can specify a list
      of encodings supported by mbstring. The default is JIS.
     
exif.decode_jis_intel
     string
    
      exif.decode_jis_intel defines 
      the image internal characterset for JIS encoded user 
      comments if image is in intel byte order (little-endian).
      This setting cannot be empty but you can specify a list
      of encodings supported by mbstring. The default is JIS.
     
