iptcembed

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thomas at anakrome dot net
05-Jul-2005 12:02


here is a small code to remove all header from a jpg file, including IPTC, Exif, XMP...



function remove_XMP($image_in, $image_dest) {

  $filename_in = addslashes($image_in);

  list($width, $height) = getimagesize($filename_in);

  $image_dest = imagecreatetruecolor($width, $height);

  $image = imagecreatefromjpeg($filename_in);

  imagecopyresampled($image_dest, $image, 0, 0, 0, 0,  $width, $height,

  $width, $height);

  imagejpeg($image_dest, $filename); 

}



the problem comes from Photoshop CS cannot read IPTC if XMP is present.

removing XMP and other header _before_ adding IPTC with iptcembed is a good way.

muguran
13-May-2005 04:41


Pay attention not add codes with length of value equal to 0; the behavior could be strange...

(e.g. $iptc_old["2#015"][0] = "")

evan at nospam dot ozhiker dot com
10-Aug-2004 12:53


You might have noticed that several metadata fields in Photoshop are not available via IPTC. 

Also, Photoshop now uses XMP for it's primary metadata, meaning IPTC is only read by Photoshop if XMP is not present.



I have written a library "PHP JPEG Metadata Toolkit" which bypasses this problem as it allows reading, writing and interpreting of virtually any type of metadata, including XMP, IPTC and EXIF. 



Try it out, and download it at: 

http://www.ozhiker.com/electronics/pjmt/index.html

dj dot cyberdance at gmx dot at
30-May-2004 09:47


Yep it's me again :-) After some time I spent searching around for other possibilities to write IPTC fields to JPEG files I found this one:



http://www.zonageek.com/software/php/jpeg/index.php



This one seems to work pretty fine, remember that you have to install PEAR to get this running (Debian package php4-pear).

dj dot cyberdance at gmx dot at
06-May-2004 07:29


I've spent a whole day debugging my code (that was based on the example below, posted by knut) until I found out, that iptcembed() only works if the image specified in jpeg_file_name already has IPTC fields included.



That means that you cannot write IPTC fields in a jpeg file without preexisting IPTC information in it.



Updating of IPTC fields also worked only with a few files, I don't really know what it depends on whether it works or not. (Well, it depends on the IPTC header, that's for sure :-)



I'm using PHP 4.2.1, maybe this is fixed in more recent versions, but I don't believe...



Nevertheless, here's some piece of code I tried:



I replaced the line



<?

$iptc_old = iptcparse ($info["APP13"]);

?>



from knut's example below with



<?

$iptc_old["2#000"][0] = chr(0) . chr(2);

?>



This creates just an empty "Header" according to the IPTC spec. This one also is included when getting IPTC info using iptcparse(). So my intention was to create a fully new header, but when using iptcembed() afterwards, the file size of the new file was a little smaller than the original but without any IPTC info stored in it.

pprem at pprem dot net
21-Feb-2004 02:04


I've a problem with the ltrim fucntion: sometimes it remove more characters than it must, so it's better to delete the line



<?

//   $image = rtrim ($image, $endchar);

?>



in the XMP_remove_from_jpeg function

pprem at pprem dot net
20-Feb-2004 08:10


Reading and changing IPTC make no problem with the PEAR function, but recent Adobe software add XMP datas on JPEG files and read them instead of IPTC datas. If you need to change IPTC on a JPEG file and want Adobe PS7 read them, you have two solutions:

- writing XMP and IPTC datas

- writing IPTC datas and removing XMP datas



Because I've not enough time to work on XMP datas, I've choosen the second solution. Here is the result of this work:



<?php

// removing XMP datas from a JPEG file

// (c) Patrick Premartin 19/02/2004



function XMP_remove_from_jpeg (&$image) {

  $xmp_str = "http://ns.adobe.com/xap/1.0/";

  $xmp_end = "<?xpacket end='w'?>";

  $n_str = strpos ($image, $xmp_str);

  $n_end = strpos ($image, $xmp_end);

  if (($n_str !== false) && ($n_end !== false) && ($n_str < $n_end)) {

    $n_str -= 4; // FF E1 .x. .y. (xy is the length of the XMP block -> first char of this block

    $n_end += strlen ($xmp_end)-1; // last char of this block

    $endchar = $image [$n_str-1];

    if ($endchar == " ") {

      $endchar = "A";

    } else {

      $endchar = " ";

    }

    $xmp_len = $n_end-$n_str+1;

    $img_len = strlen ($image);

    $len = $img_len - $xmp_len;

    for ($i = $n_str; $i < $img_len; $i ++) {

      if ($i < $len) {

        $image [$i] = $image [$i+$xmp_len];

      } else {

        $image [$i] = $endchar;

      }

    }

    $image = rtrim ($image, $endchar);

    return true;

  } else {

    return false;

  }

}



function XMP_remove_from_jpegfile ($filename_in, $filename_out="") {

  if (""==$filename_out) {

    $filename_out = $filename_in;

  }

  if ((""!=$filename_in) && (file_exists ($filename_in)) && (($len_in = filesize ($filename_in)) > 0)) {

    // chargement du fichier en mmoire

    $f_in = fopen ($filename_in, "rb");

    $img = fread ($f_in, $len_in);

    fclose ($f_in);

    // suppression du XMP de l'image

    if (XMP_remove_from_jpeg ($img)) {

      // enregistrement du fichier sur disque

      $f_out = fopen ($filename_out, "wb");

      fwrite ($f_out, $img, strlen ($img));

      fclose ($f_out);

    }

  }

}



XMP_remove_from_jpegfile ("ps7_hr.jpg", "ps7_hr_.jpg"); // create a new picture without XMP datas



XMP_remove_from_jpegfile ("ps8_hr.jpg"); // replace the existing file

?>



In the future, I'll work on changing XMP datas and IPTC in the same way and will publish it ther or as a in PEAR.



May the force be with us :-)

pprem
15-Feb-2004 11:00


I confirm: Photoshop 7 and other recent Adobe programs use XMP instead of IPTC. They write datas in IPTC format only for compatibility with older programs, but use only XMP.



I'm working on a program that write XMP and IPTC together and probably post it here as soon as possible.

collord
28-Jan-2004 05:20


Regarding issues with photoshop IPTC... Photoshop actually prefers a different embedded metadata format, XMP, which is RDF-based. When Photoshop manages metadata via File Info, what you're actually doing is manipulating RDF in a "photoshop" namespace as well as the standard Dublin Core (dc) namespace, and a couple others. When a file is written that supports IPTC, the equivalent fields e.g. copyright, keywords, etc. are serialized into the IPTC block. 



So, if one manipulates the IPTC block of a Photoshop-generated image and leaves the XMP block alone, it's my guess that Photoshop will treat data from the XMP as authoritative. 



HTH, jerritt

jofr at gmx dot com
30-Dec-2003 02:42


I found out, that iptcembed does not overwrite the full IPTC-Tags from Photoshop.

If you modify the IPTC-Tag with iptcembed, Photoshop will still show you the old IPTC-Tag.

Programs like Fotostation works fine.



JO

bob at lucid-systems dot com
23-Aug-2002 06:37


The above example doesn't handle keywords properly. The 'create string' code needs to be modified to cater for the array:



$c = count ($iptc_old[$s]);

for ($i=0; $i <$c; $i++)

    {

    $iptc_new .= iptc_maketag(2, $tag, $iptc_old[$s][$i]);

    }

rupix at rediffmail dot com
28-Jan-2002 08:24


Windows makes a distinction between 'text' and 'binary' files. So if you run the above code on a windows platform, it will produce a garbled image. To overcome this problem put the file mode in fopen() as 'wb' instead of 'w'. 



Cheerio !!



Rupinder

knut dot satre dot NoSpam at No_Spam dot nord dot no
28-Jan-2002 07:45


Example to read IPTC text from an image, changing the text an write to a new file using the functions iptcparse and iptcembed.

 

Also a list of the most common IPTC fields.



<?

// original file name

$image_name_old = "test.jpg";



// New file name

$image_name_new = "test2.jpg";



// Reads the IPTC text in to the array '$iptc'

// The number after the '#' is the IPTC field

// Ex: $iptc["2#120"][0] is Caption

// $iptc["2#055"][0]; is Creation date

$size = GetImageSize ("$image_name_old",&$info);

$iptc_old = iptcparse ($info["APP13"]);



// Adding or replacing IPTC text

   // This ex. replace the original category or create it if it dos not exist

   $iptc_old["2#015"][0] = "Sport";

   // .. and adding more text to the original caption

   $iptc_old["2#120"][0] .= " More caption text";



   // Making the new IPTC string

   foreach (array_keys($iptc_old) as $s){

      // Finds the IPTC numbers

      $tag = str_replace("2#", "", $s);

      // Creating the string

      $iptc_new .= iptc_maketag(2, $tag, $iptc_old[$s][0]);

   }



// The original file and the new IPTC Text into $content

// Mode 0 - puts the image file into $content

// Mode 1 - puts the image file into $content and directly to the web client

// Mode 2 - puts the image file to web client

$mode = 0;

$content = iptcembed($iptc_new, $image_name_old, $mode);



// writes the new file

$fp = fopen($image_name_new, "w");

fwrite($fp, $content);

fclose($fp);



// Function to format the new IPTC text, (thanks to Thies C. Arntzen)

function iptc_maketag($rec,$dat,$val){

         $len = strlen($val);

         if ($len < 0x8000)

                  return chr(0x1c).chr($rec).chr($dat).

                  chr($len >> 8).

                  chr($len & 0xff).

                  $val;

         else

                  return chr(0x1c).chr($rec).chr($dat).

                  chr(0x80).chr(0x04).

                  chr(($len >> 24) & 0xff).

                  chr(($len >> 16) & 0xff).

                  chr(($len >> 8 ) & 0xff).

                  chr(($len ) & 0xff).

                  $val;

}



?>



--- The most common IPTC Fileds

005 - Object Name

007 - Edit Status

010 - Priority

015 - Category

020 - Supplemental Category

022 - Fixture Identifier

025 - Keywords

030 - Release Date

035 - Release Time

040 - Special Instructions

045 - Reference Service

047 - Reference Date

050 - Reference Number

055 - Created Date

060 - Created Time

065 - Originating Program

070 - Program Version

075 - Object Cycle

080 - Byline

085 - Byline Title

090 - City

095 - Province State

100 - Country Code

101 - Country

103 - Original Transmission Reference

105 - Headline

110 - Credit

115 - Source

116 - Copyright String

120 - Caption

121 - Local Caption

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