/// <summary>
/// Advance the stream to a new word boundary, padding if necessary
/// </summary>
/// <param name="tiffStream"></param>
/// <returns></returns>
static uint SeekToNewWord(TiffStreamWriter tiffStream)
{
var offset = (uint)tiffStream.SeekWord(0, SeekOrigin.End);
if (offset % 2 > 0)
{
tiffStream.WriteByte(0x00); offset++;
} // advance if not on word boundary
return(offset);
}
public void Save(Stream stream)
{
using (var tiffStream = new TiffStreamWriter(forceBigEndian: IsBigEndian))
{
WriteTo(tiffStream);
tiffStream.Seek(0, SeekOrigin.Begin);
tiffStream.CopyTo(stream);
}
}
public void Save(string fileName)
{
using (var tiffStream = new TiffStreamWriter(forceBigEndian: IsBigEndian))
{
WriteTo(tiffStream);
using (var stream = new FileStream(fileName, FileMode.CreateNew, FileAccess.ReadWrite, FileShare.Read))
{
tiffStream.Seek(0, SeekOrigin.Begin);
tiffStream.CopyTo(stream);
}
}
}
void WriteTo(TiffStreamWriter tiffStream)
{
tiffStream.WriteHeader();
tiffStream.WriteDWord(8); // IFD0 will always be immediately after the header, at offset 0x08
uint previousOffset = 0;
foreach (var image in Images)
{
var imageOffset = WriteImage(image, tiffStream);
// update the pointer from the previous image, then seek back to the current offset
if (previousOffset != 0)
{
tiffStream.UpdateIFDPointer(previousOffset, imageOffset);
tiffStream.Seek(imageOffset, SeekOrigin.Begin);
}
previousOffset = imageOffset;
}
}
uint WriteImage(Image image, TiffStreamWriter tiffStream)
{
if (image.SubImages.Count > 0)
{
throw new TiffWriteException("Writing pyramid/subimage files is not currently supported");
}
var imageOffset = SeekToNewWord(tiffStream);
// prep the current set of tags, and write the initial IFD
if (image.Exif?.Count > 0 && !image.Tags.Any(t => t.ID == (ushort)PrivateTags.ExifIFD))
{
// We have EXIF tags to write, and no current ExifIFD pointer
image.Tags.Add(new Tag <uint>()
{
ID = (ushort)PrivateTags.ExifIFD, DataType = TagDataType.Long, Length = 1, Values = new uint[] { 0 }
});
}
else if ((image.Exif?.Count ?? 0) == 0 && image.Tags.Any(t => t.ID == (ushort)PrivateTags.ExifIFD))
{
// There are no EXIF tags to write, get rid of the superfluous pointer
image.Tags.RemoveAll(t => t.ID == (ushort)Tags.PrivateTags.ExifIFD);
}
tiffStream.WriteIFD(image.Tags);
// write image strip data
tiffStream.WriteStrips(imageOffset, image.Strips.ToArray());
// write Exif block, if necessary, and update the original tag pointer
if (image.Exif?.Count > 0)
{
var exifIfdOffset = SeekToNewWord(tiffStream);
tiffStream.WriteIFD(image.Exif);
var exifTag = image.Tags.Where(t => t.ID == (ushort)PrivateTags.ExifIFD).First() as Tag <uint>;
exifTag.Values[0] = exifIfdOffset;
tiffStream.UpdateTags(exifTag);
}
return(imageOffset);
}
