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Question:

How to do simple staf (get XMP data) with the library?

Jan 26 '15 at 08:54

I am very new to this lib and want to ask few questions:

  1. Does this support EXIF tags?
  2. Where are the domains documented? e.g. Iptc4xmpCore, what are names for other cores/props?

  3. I tried to get XMP data like: CkXmp xmp;

            bool success;
        success = xmp.LoadAppFile("C:\\Users\\User\\Downloads\\sample1.jpg");
        CkXml *xml = 0;
        xml = xmp.GetEmbedded(0);
        if (!(xml == 0))
        {
            StringSet(temporary_string, "Failed!");
            success = xml->SaveXml("xmpMetaData.xml");
        }
        delete xml;

But the result was empty since xmp.get_NumEmbedded() = 0. Why? What am I doing wrong?

Thanks much!!

Accepted Answer

Mikayel,

Chilkat XMP does not support EXIF tags. :(

The AddNsMapping can be used to add namespaces (domains) that are not automatically hard-coded within Chilkat XMP. The ones that are hard coded are: 

"dc"  -- "http://purl.org/dc/elements/1.1/"
"xmpPLUS"  -- "http://ns.adobe.com/xap/1.0/PLUS/"
"MicrosoftPhoto"  -- "http://ns.microsoft.com/photo/1.0/"
"Iptc4xmpCore"  -- "http://iptc.org/std/Iptc4xmpCore/1.0/xmlns/"
"exif"  -- "http://ns.adobe.com/exif/1.0/"
"pdf"  -- "http://ns.adobe.com/pdf/1.3/"
"photoshop"  -- "http://ns.adobe.com/photoshop/1.0/"
"tiff"  -- "http://ns.adobe.com/tiff/1.0/"
"xap"  -- "http://ns.adobe.com/xap/1.0/"
"stRef"  -- "http://ns.adobe.com/xap/1.0/sType/ResourceRef"
"xapMM"/"xmpMM"  -- "http://ns.adobe.com/xap/1.0/mm/"
"xapRights"  -- "http://ns.adobe.com/xap/1.0/rights/"
"xmp"  -- "http://ns.adobe.com/xap/1.0/"
"xmpBJ"  -- "http://ns.adobe.com/xap/1.0/bj/"
"xmpTPg"  -- "http://ns.adobe.com/xap/1.0/t/pg/"
"xmpDM"  -- "http://ns.adobe.com/xmp/1.0/DynamicMedia/"
"xmpRights"  -- "http://ns.adobe.com/xap/1.0/rights/"
"crs"  -- "http://ns.adobe.com/camera-rawsettings/1.0/"
"aux"  -- "http://ns.adobe.com/exif/1.0/aux/"

If get_NumEmbedded did not return the expected count, then turn on verbose logging by setting the VerboseLogging property = true (xmp.put_VerboseLogging(true)), make sure you're using the latest version of Chilkat, which is v9.5.0.47 right now, and examine the LastErrorText after the call to LoadAppFile so you can see the internals/details of the JPG parsing.