public class XmpPacketWrapper : MetadataPackage, 
	IXmpType

Public Class XmpPacketWrapper
	Inherits MetadataPackage
	Implements IXmpType

public ref class XmpPacketWrapper : public MetadataPackage, 
	IXmpType

type XmpPacketWrapper =  
    class
        inherit MetadataPackage
        interface IXmpType
    end

using (Metadata metadata = new Metadata(Constants.GifWithXmp))
{
    IXmp root = metadata.GetRootPackage() as IXmp;
    if (root != null && root.XmpPackage != null)
    {
        // if there is no such scheme in the XMP package we should create it
        if (root.XmpPackage.Schemes.DublinCore == null)
        {
            root.XmpPackage.Schemes.DublinCore = new XmpDublinCorePackage();
        }
        root.XmpPackage.Schemes.DublinCore.Format = "image/gif";
        root.XmpPackage.Schemes.DublinCore.SetRights("Copyright (C) 2011-2021 GroupDocs. All Rights Reserved");
        root.XmpPackage.Schemes.DublinCore.SetSubject("test");

        if (root.XmpPackage.Schemes.CameraRaw == null)
        {
            root.XmpPackage.Schemes.CameraRaw = new XmpCameraRawPackage();
        }
        root.XmpPackage.Schemes.CameraRaw.Shadows = 50;
        root.XmpPackage.Schemes.CameraRaw.AutoBrightness = true;
        root.XmpPackage.Schemes.CameraRaw.AutoExposure = true;
        root.XmpPackage.Schemes.CameraRaw.CameraProfile = "test";
        root.XmpPackage.Schemes.CameraRaw.Exposure = 0.0001;

        // If you don't want to keep the old values just replace the whole scheme
        root.XmpPackage.Schemes.XmpBasic = new XmpBasicPackage();
        root.XmpPackage.Schemes.XmpBasic.CreateDate = DateTime.Today;
        root.XmpPackage.Schemes.XmpBasic.BaseUrl = "https://groupdocs.com";
        root.XmpPackage.Schemes.XmpBasic.Rating = 5;

        root.XmpPackage.Schemes.BasicJobTicket = new XmpBasicJobTicketPackage();

        // Set a complex type property
        root.XmpPackage.Schemes.BasicJobTicket.Jobs = new[]
        {
            new XmpJob
            {
                ID = "1",
                Name = "test job",
                Url = "https://groupdocs.com"
            },
        };

        // ... 

        metadata.Save(Constants.OutputGif);
    }
}