private static byte[] ExtractXMPPacket(BitmapMetadata xmp)
{
BitmapMetadata tiffMetaData = new BitmapMetadata("tiff");
tiffMetaData.SetQuery("/ifd/xmp", new BitmapMetadata("xmp"));
foreach (string tag in xmp)
{
object value = xmp.GetQuery(tag);
if (value is BitmapMetadata xmpSub)
{
CopySubIFDRecursive(ref tiffMetaData, xmpSub, "/ifd/xmp" + tag);
}
else
{
tiffMetaData.SetQuery("/ifd/xmp" + tag, value);
}
}
byte[] xmpBytes = null;
using (MemoryStream stream = new MemoryStream())
{
// Create a dummy tiff to extract the XMP packet from.
BitmapSource source = BitmapSource.Create(1, 1, 96.0, 96.0, PixelFormats.Gray8, null, new byte[] { 255 }, 1);
TiffBitmapEncoder encoder = new TiffBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(source, null, tiffMetaData, null));
encoder.Save(stream);
xmpBytes = TiffReader.ExtractXMP(stream);
}
return(xmpBytes);
}
/// <summary>
/// Extracts the meta data from the image.
/// </summary>
/// <param name="bytes">The output bytes.</param>
/// <param name="exif">set to <c>true</c> if the EXIF data is requested.</param>
/// <returns><c>true</c> if the meta data was extracted; otherwise, <c>false</c>.</returns>
/// <exception cref="System.ObjectDisposedException">The object has been disposed.</exception>
public bool Extract(out byte[] bytes, bool exif)
{
if (disposed)
{
throw new ObjectDisposedException(nameof(ImageMetaData));
}
bytes = null;
// Return the cached data if it has already been extracted.
if (exif)
{
if (extractedExif)
{
bytes = exifBytes;
return(bytes != null);
}
}
else
{
if (extractedXMP)
{
bytes = xmpBytes;
return(bytes != null);
}
}
#if !GDIPLUS
BitmapMetadata metaData = null;
try
{
metaData = image.Metadata as BitmapMetadata;
}
catch (NotSupportedException)
{
}
if (metaData == null)
{
extractedExif = true;
extractedXMP = true;
return(false);
}
if (exif)
{
BitmapMetadata exifMetaData = MetaDataConverter.GetEXIFMetaData(metaData);
if (exifMetaData == null)
{
extractedExif = true;
return(false);
}
metaData = exifMetaData;
}
else
{
BitmapMetadata xmpMetaData = MetaDataConverter.GetXMPMetaData(metaData);
if (xmpMetaData == null)
{
extractedXMP = true;
return(false);
}
metaData = xmpMetaData;
}
#endif
if (exif)
{
using (MemoryStream ms = new MemoryStream())
{
#if GDIPLUS
image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
#else
JpegBitmapEncoder enc = new JpegBitmapEncoder();
enc.Frames.Add(BitmapFrame.Create(image, null, metaData, null));
enc.Save(ms);
#endif
exifBytes = JpegReader.ExtractEXIF(ms.GetBuffer());
extractedExif = true;
bytes = exifBytes;
}
}
else
{
using (MemoryStream ms = new MemoryStream())
{
#if GDIPLUS
image.Save(ms, System.Drawing.Imaging.ImageFormat.Tiff);
#else
TiffBitmapEncoder enc = new TiffBitmapEncoder();
enc.Frames.Add(BitmapFrame.Create(image, null, metaData, null));
enc.Save(ms);
#endif
xmpBytes = TiffReader.ExtractXMP(ms);
extractedXMP = true;
bytes = xmpBytes;
}
}
return(bytes != null);
}