How to add people tagging metadata

Question

I'm writing people tagging metadata to a jpg file that has yet no xmp block. Here is my code:

// add padding here already

...

// This works fine as I can see RegionInfo is created with WICExplorer

bitmapMetadata.SetQuery("/xmp/MP:RegionInfo", new BitmapMetadata("xmpstruct"));

// This works fine as I can see Regions is created with WICExplorer

bitmapMetadata.SetQuery("/xmp/MP:RegionInfo/MPRI:Regions", new BitmapMetadata("xmpbag"));

// This works fine as I can see 0 (XMP Struct Reader) is created with WICExplorer

bitmapMetadata.SetQuery("/xmp/MP:RegionInfo/MPRI:Regions/{ulong=0}", new BitmapMetadata("xmpstruct"));

// These two statement give System.AccessViolationException. Why?

bitmapMetadata.SetQuery("/xmp/MP:RegionInfo/MPRI:Regions/{ulong=0}/PersonDisplayName", "somename"));

bitmapMetadata.SetQuery("/xmp/MP:RegionInfo/MPRI:Regions/{ulong=0}/Rectangle", "somerectangle"));

//...others as... jpegEncoder.Frames.Add(...

The last two SetQuery() statements are not working. I don't know why? Could you help me out? Thanks!

Answer 1

Did you add padding to the file?

bitmapMetadata.SetQuery("/xmp/PaddingSchema:Padding", 5012);

I provide some more details here:

http://www.tassography.com/blog.aspx?b=63392908013