Working with IPTC IIM metadata
What is IPTC IIM?
The IPTC Information Interchange Model (IIM) is a set of metadata properties that can be applied to text, images, and other media types. The standard also defines a complex data structure that is utilized to store the properties. The IPTC IIM was developed by the International Press Telecommunications Council (IPTC) to expedite the international exchange of news among newspapers and news agencies. But nowadays it’s commonly used by amateur and commercial photographers. The standard is supported by many image creation and manipulation programs. IPTC IIM metadata can be embedded into a variety of image formats such as JPEG, TIFF, etc.
Reading basic IPTC IIM properties
To access IPTC metadata in a file of any supported format, GroupDocs.Metadata provides the IIptc.IptcPackage property. The following are the steps to read IPTC metadata:
- Load a file that contains IPTC metadata
- Extract the IPTC metadata package using the IIptc.IptcPackage property
- Read properties of the IptcApplicationRecord and IptcEnvelopeRecord class instances
The following code snippet gets IPTC properties of a JPEG image and displays them on the screen.
AdvancedUsage.WorkingWithMetadataStandards.
using (Metadata metadata = new Metadata(Constants.JpegWithIptc))
{
IIptc root = metadata.GetRootPackage() as IIptc;
if (root != null && root.IptcPackage != null)
{
if (root.IptcPackage.EnvelopeRecord != null)
{
Console.WriteLine(root.IptcPackage.EnvelopeRecord.DateSent);
Console.WriteLine(root.IptcPackage.EnvelopeRecord.Destination);
Console.WriteLine(root.IptcPackage.EnvelopeRecord.FileFormat);
Console.WriteLine(root.IptcPackage.EnvelopeRecord.FileFormatVersion);
// ...
}
if (root.IptcPackage.ApplicationRecord != null)
{
Console.WriteLine(root.IptcPackage.ApplicationRecord.Headline);
Console.WriteLine(root.IptcPackage.ApplicationRecord.ByLine);
Console.WriteLine(root.IptcPackage.ApplicationRecord.ByLineTitle);
Console.WriteLine(root.IptcPackage.ApplicationRecord.CaptionAbstract);
Console.WriteLine(root.IptcPackage.ApplicationRecord.City);
Console.WriteLine(root.IptcPackage.ApplicationRecord.DateCreated);
Console.WriteLine(root.IptcPackage.ApplicationRecord.ReleaseDate);
// ...
}
}
}
Reading all IPTC IIM datasets
In some cases, it’s necessary to read all IPTC datasets (metadata properties) from a file, including custom ones. To achieve this the GroupDocs.Metadata API provides direct access to the IPTC datasets extracted from a file.
- Load a file that contains IPTC metadata
- Extract the IPTC metadata package using the IIptc.IptcPackage property
- Iterate through all IPTC datasets
AdvancedUsage.WorkingWithMetadataStandards.
using (Metadata metadata = new Metadata(Constants.PsdWithIptc))
{
IIptc root = metadata.GetRootPackage() as IIptc;
if (root != null && root.IptcPackage != null)
{
foreach (var dataSet in root.IptcPackage.ToDataSetList())
{
Console.WriteLine(dataSet.RecordNumber);
Console.WriteLine(dataSet.DataSetNumber);
Console.WriteLine(dataSet.AlternativeName);
if (dataSet.Value.Type == MetadataPropertyType.PropertyValueArray)
{
foreach (var value in dataSet.Value.ToArray<PropertyValue>())
{
Console.Write("{0}, ", value);
}
Console.WriteLine();
}
else
{
Console.WriteLine(dataSet.Value);
}
}
}
}
Updating IPTC IIM properties
The GroupDocs.Metadata API facilitates the user to update IPTC metadata in a convenient way - using the IptcRecordSet class properties. Follow the below steps to update IPTC metadata in a file of any supported format.
- Load a file that contains IPTC metadata
- Extract the IPTC metadata package using the IIptc.IptcPackage property
- Assign values to desired IPTC properties
- Save the changes
AdvancedUsage.WorkingWithMetadataStandards.
using (Metadata metadata = new Metadata(Constants.InputJpeg))
{
IIptc root = metadata.GetRootPackage() as IIptc;
if (root != null)
{
// Set the IPTC package if it's missing
if (root.IptcPackage == null)
{
root.IptcPackage = new IptcRecordSet();
}
if (root.IptcPackage.EnvelopeRecord == null)
{
root.IptcPackage.EnvelopeRecord = new IptcEnvelopeRecord();
}
root.IptcPackage.EnvelopeRecord.DateSent = DateTime.Now;
root.IptcPackage.EnvelopeRecord.ProductID = Guid.NewGuid().ToString();
// ...
if (root.IptcPackage.ApplicationRecord == null)
{
root.IptcPackage.ApplicationRecord = new IptcApplicationRecord();
}
root.IptcPackage.ApplicationRecord.ByLine = "GroupDocs";
root.IptcPackage.ApplicationRecord.Headline = "test";
root.IptcPackage.ApplicationRecord.ByLineTitle = "code sample";
root.IptcPackage.ApplicationRecord.ReleaseDate = DateTime.Today;
// ...
metadata.Save(Constants.OutputJpeg);
}
}
Adding or updating custom IPTC IIM datasets
The GroupDocs.Metadata API allows adding or updating custom datasets in an IPTC package.
- Load a file that contains IPTC metadata
- Extract the IPTC metadata package using the IIptc.IptcPackage property
- Set the IPTC package if it’s missing
- Add any number of custom datasets to the package (Please see the IptcDataSet class for more information)
- Save the changes
AdvancedUsage.WorkingWithMetadataStandards.
using (Metadata metadata = new Metadata(Constants.PsdWithIptc))
{
IIptc root = metadata.GetRootPackage() as IIptc;
if (root != null)
{
// Set the IPTC package if it's missing
if (root.IptcPackage == null)
{
root.IptcPackage = new IptcRecordSet();
}
// Add a know property using the DataSet API
root.IptcPackage.Set(new IptcDataSet((byte)IptcRecordType.ApplicationRecord, (byte)IptcApplicationRecordDataSet.BylineTitle, "test code sample"));
// Add a custom IPTC DataSet
root.IptcPackage.Set(new IptcDataSet(255, 255, new byte[] { 1, 2, 3 }));
metadata.Save(Constants.OutputPsd);
}
}
Adding repeatable IPTC IIM datasets
According to the IPTC IIM specification some datasets can be added to a record multiple times. The code snippet below demonstrates how to add a repeatable dataset to a record.
AdvancedUsage.WorkingWithMetadataStandards.
using (Metadata metadata = new Metadata(Constants.PsdWithIptc))
{
IIptc root = (IIptc)metadata.GetRootPackage();
// Set the IPTC package if it's missing
if (root.IptcPackage == null)
{
root.IptcPackage = new IptcRecordSet();
}
root.IptcPackage.Add(new IptcDataSet((byte)IptcRecordType.ApplicationRecord, (byte)IptcApplicationRecordDataSet.Keywords, "keyword 1"));
root.IptcPackage.Add(new IptcDataSet((byte)IptcRecordType.ApplicationRecord, (byte)IptcApplicationRecordDataSet.Keywords, "keyword 2"));
root.IptcPackage.Add(new IptcDataSet((byte)IptcRecordType.ApplicationRecord, (byte)IptcApplicationRecordDataSet.Keywords, "keyword 3"));
metadata.Save(Constants.OutputPsd);
}
// Check the output file
using (Metadata metadata = new Metadata(Constants.OutputPsd))
{
IIptc root = (IIptc)metadata.GetRootPackage();
var keywordsProperty = root.IptcPackage.ApplicationRecord[(byte)IptcApplicationRecordDataSet.Keywords];
foreach (var value in keywordsProperty.Value.ToArray<PropertyValue>())
{
Console.WriteLine(value);
}
}
Removing IPTC IIM metadata
To remove the IPTC package from a file just assign null to the IIptc.IptcPackage property. The code sample below shows how to remove IPTC metadata from a file.
AdvancedUsage.WorkingWithMetadataStandards.
using (Metadata metadata = new Metadata(Constants.JpegWithIptc))
{
IIptc root = metadata.GetRootPackage() as IIptc;
if (root != null)
{
root.IptcPackage = null;
metadata.Save(Constants.OutputJpeg);
}
}
More resources
GitHub examples
You may easily run the code above and see the feature in action in our GitHub examples:
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