private ByteVector RenderExifSegment()
{
IFDTag exif = ImageTag.Exif;
if (exif == null)
{
return(null);
}
uint first_ifd_offset = 8;
var renderer = new IFDRenderer(true, exif.Structure, first_ifd_offset);
ByteVector exif_data = renderer.Render();
uint segment_size = (uint)(first_ifd_offset + exif_data.Count + 2 + 6);
if (segment_size > ushort.MaxValue)
{
throw new Exception("Exif Segment is too big to render");
}
ByteVector data = new ByteVector(new byte[] { 0xFF, (byte)Marker.APP1 });
data.Add(ByteVector.FromUShort((ushort)segment_size));
data.Add("Exif\0\0");
data.Add(ByteVector.FromString("MM", StringType.Latin1));
data.Add(ByteVector.FromUShort(42));
data.Add(ByteVector.FromUInt(first_ifd_offset));
data.Add(exif_data);
return(data);
}
public ByteVector Render(bool is_bigendian, uint offset, out ushort type, out uint count)
{
type = (ushort)IFDEntryType.Undefined;
var renderer = new IFDRenderer(this.is_bigendian ?? is_bigendian, Structure, absolute_offset?offset + ifd_offset:ifd_offset);
ByteVector data = renderer.Render();
data.Insert(0, prefix);
count = (uint)data.Count;
return(data);
}
private void WriteFile()
{
IFDTag exif = ImageTag.Exif;
if (exif == null)
{
throw new Exception("Tiff file without tags");
}
UpdateTags(exif);
uint first_ifd_offset = 8;
ByteVector data = RenderHeader(first_ifd_offset);
var renderer = new IFDRenderer(IsBigEndian, exif.Structure, first_ifd_offset);
data.Add(renderer.Render());
Insert(data, 0, Length);
}
/// <summary>
/// Creates a <see cref="ByteVector"/> for the Exif segment of this file
/// </summary>
/// <returns>
/// A <see cref="ByteVector"/> with the whole Exif segment, if exif tags
/// exists, otherwise null.
/// </returns>
ByteVector RenderExifSegment()
{
// Check, if IFD0 is contained
IFDTag exif = ImageTag.Exif;
if (exif == null)
{
return(null);
}
// first IFD starts at 8
uint first_ifd_offset = 8;
// Render IFD0
// FIXME: store endianess and use it here
var renderer = new IFDRenderer(true, exif.Structure, first_ifd_offset);
ByteVector exif_data = renderer.Render();
uint segment_size = (uint)(first_ifd_offset + exif_data.Count + 2 + 6);
// do not render data segments, which cannot fit into the possible segment size
if (segment_size > ushort.MaxValue)
{
throw new Exception("Exif Segment is too big to render");
}
// Create whole segment
var data = new ByteVector(new byte[] { 0xFF, (byte)Marker.APP1 })
{
ByteVector.FromUShort((ushort)segment_size),
"Exif\0\0",
ByteVector.FromString("MM", StringType.Latin1),
ByteVector.FromUShort(42),
ByteVector.FromUInt(first_ifd_offset),
// Add ifd data itself
exif_data
};
return(data);
}
/// <summary>
/// Renders the current instance to a <see cref="ByteVector"/>
/// </summary>
/// <param name="is_bigendian">
/// A <see cref="System.Boolean"/> indicating the endianess for rendering.
/// </param>
/// <param name="offset">
/// A <see cref="System.UInt32"/> with the offset, the data is stored.
/// </param>
/// <param name="type">
/// A <see cref="System.UInt16"/> the ID of the type, which is rendered
/// </param>
/// <param name="count">
/// A <see cref="System.UInt32"/> with the count of the values which are
/// rendered.
/// </param>
/// <returns>
/// A <see cref="ByteVector"/> with the rendered data.
/// </returns>
public ByteVector Render (bool is_bigendian, uint offset, out ushort type, out uint count)
{
type = (ushort) IFDEntryType.Undefined;
var renderer =
new IFDRenderer (this.is_bigendian ?? is_bigendian, Structure, absolute_offset ? offset + ifd_offset : ifd_offset);
ByteVector data = renderer.Render ();
data.Insert (0, prefix);
count = (uint) data.Count;
return data;
}
