private void ReadImageFileHeader()
{
_reader.Stream.Position = 0;
short byteOrder = _reader.ReadInt16();
if (byteOrder == 0x4949)
{
_reader.StreamIsLittleEndian = true;
}
else if (byteOrder == 0x4d4d)
{
_reader.StreamIsLittleEndian = false;
}
else
{
throw new Exception($"Not a TIFF file: {byteOrder}");
}
short meaningOfLife = _reader.ReadInt16();
if (meaningOfLife == 42)
{
_bigTiff = false;
}
else if (meaningOfLife == 43)
{
_bigTiff = true;
}
else
{
throw new Exception($"Not a TIFF file. Life: {meaningOfLife}");
}
if (_bigTiff)
{
if (_reader.ReadUInt16() != 8)
{
throw new Exception("Offset should be size 8 in BigTIFF");
}
_reader.ReadUInt16(); // always 0
}
}
private object ReadFieldValueAsObject(BinaryReader2 reader, FieldType fieldType)
{
switch (fieldType)
{
case FieldType.Int64:
return(reader.ReadInt64());
case FieldType.UInt64:
return(reader.ReadInt64());
case FieldType.Int32:
return(reader.ReadInt32());
case FieldType.UInt32:
return(reader.ReadUInt32());
case FieldType.Int16:
return(reader.ReadInt16());
case FieldType.UInt16:
return(reader.ReadUInt16());
case FieldType.Byte:
return(reader.ReadByte());
case FieldType.SByte:
return(reader.ReadSByte());
case FieldType.Float:
return(reader.ReadSingle());
case FieldType.Double:
return(reader.ReadDouble());
case FieldType.Rational:
return(new Rational(reader.ReadUInt32(), reader.ReadUInt32()));
case FieldType.SRational:
return(new SRational(reader.ReadInt32(), reader.ReadInt32()));
}
Console.WriteLine($"Unknown field type {fieldType}");
return(0);
}
private ImageFileDirectory[] ReadImageFileDirectories()
{
var ifdList = new List <ImageFileDirectory>();
long ifdOffset = _bigTiff ? _reader.ReadInt64() : _reader.ReadUInt32();
while (ifdOffset > 0)
{
_reader.Stream.Position = ifdOffset;
var ifd = new ImageFileDirectory();
long numFields = _bigTiff ? _reader.ReadInt64() : _reader.ReadUInt16();
int sizeInBytes = (int)numFields * (2 + 2 + 2 * (_bigTiff ? 8 : 4)) + (_bigTiff ? 8 : 4);
using (var ifdReader = new BinaryReader2(new MemoryStream(_reader.ReadBytes(sizeInBytes))))
{
ifdReader.StreamIsLittleEndian = _reader.StreamIsLittleEndian;
for (int i = 0; i < numFields; i++)
{
IfdTag tag = (IfdTag)ifdReader.ReadUInt16();
FieldType fieldType = (FieldType)ifdReader.ReadUInt16();
int numValues = _bigTiff ? (int)ifdReader.ReadInt64() : (int)ifdReader.ReadUInt32();
long pos = ifdReader.Stream.Position;
switch (tag)
{
case IfdTag.ImageWidth:
{
ifd.ImageWidth = ReadFieldValue <int>(ifdReader, fieldType);
}
break;
case IfdTag.ImageHeight:
{
ifd.ImageHeight = ReadFieldValue <int>(ifdReader, fieldType);
}
break;
case IfdTag.BitsPerSample:
{
if (numValues == 1)
{
ifd.BitsPerSample = ReadFieldValue <ushort>(ifdReader, fieldType);
}
else
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
var bitsPerSamples = ReadFieldValues <ushort>(_reader, fieldType, numValues);
ifd.BitsPerSample = (ushort)bitsPerSamples[0];
if (bitsPerSamples.Any(bps => bps != ifd.BitsPerSample))
{
throw new NotSupportedException($"BitsPerSample must be the same for all samples: {string.Join(", ", bitsPerSamples)}");
}
}
}
break;
case IfdTag.PhotometricInterpretation:
{
ifd.PhotometricInterpretation = ReadFieldValue <PhotometricInterpretation>(ifdReader, fieldType);
}
break;
case IfdTag.Compression:
{
ifd.Compression = ReadFieldValue <Compression>(ifdReader, fieldType);
}
break;
case IfdTag.SamplesPerPixel:
{
ifd.SamplesPerPixel = ReadFieldValue <ushort>(ifdReader, fieldType);
}
break;
case IfdTag.RowsPerStrip:
{
ifd.RowsPerStrip = ReadFieldValue <uint>(ifdReader, fieldType);
}
break;
case IfdTag.PlanarConfiguration:
{
ifd.PlanarConfiguration = ReadFieldValue <PlanarConfiguration>(ifdReader, fieldType);
}
break;
case IfdTag.SampleFormat:
{
ifd.SampleFormat = ReadFieldValue <SampleFormat>(ifdReader, fieldType);
}
break;
case IfdTag.StripOffsets:
{
if (numValues == 1)
{
ifd.StripOffsets = new[] { ReadFieldValue <long>(ifdReader, fieldType) };
}
else
{
_reader.Stream.Position = ReadFieldValue <long>(ifdReader, fieldType);
ifd.StripOffsets = ReadFieldValues <long>(_reader, fieldType, numValues);
}
}
break;
case IfdTag.StripByteCounts:
{
if (numValues == 1)
{
ifd.StripByteCounts = new[] { ReadFieldValue <long>(ifdReader, fieldType) };
}
else
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.StripByteCounts = ReadFieldValues <long>(_reader, fieldType, numValues);
}
}
break;
case IfdTag.Artist:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.Artist = ReadAsciiField(_reader, numValues);
}
break;
case IfdTag.Copyright:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.Copyright = ReadAsciiField(_reader, numValues);
}
break;
case IfdTag.DateTime:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
string text = ReadAsciiField(_reader, numValues);
DateTime.TryParseExact(text, "yyyy:MM:dd HH:mm:ss", CultureInfo.InvariantCulture, DateTimeStyles.None, out ifd.DateTime);
}
break;
case IfdTag.ExtraSamples:
{
ifd.ExtraSamples = ReadFieldValue <ushort>(ifdReader, fieldType);
}
break;
case IfdTag.HostComputer:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.HostComputer = ReadAsciiField(_reader, numValues);
}
break;
case IfdTag.ImageDescription:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.ImageDescription = ReadAsciiField(_reader, numValues);
}
break;
case IfdTag.Make:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.Make = ReadAsciiField(_reader, numValues);
}
break;
case IfdTag.Model:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.Model = ReadAsciiField(_reader, numValues);
}
break;
case IfdTag.Orientation:
{
ifd.Orientation = ReadFieldValue <ushort>(ifdReader, fieldType);
}
break;
case IfdTag.Software:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.Software = ReadAsciiField(_reader, numValues);
}
break;
case IfdTag.DocumentName:
{
_reader.Stream.Position = ReadFieldOffset(ifdReader);
ifd.DocumentName = ReadAsciiField(_reader, numValues);
}
break;
case IfdTag.FillOrder:
{
ifd.FillOrder = ReadFieldValue <ushort>(ifdReader, fieldType);
}
break;
default:
{
if (numValues == 1)
{
object value = ReadFieldValueAsObject(ifdReader, fieldType);
ifd.Entries[tag] = new IfdEntry {
Tag = tag, FieldType = fieldType, Value = value
};
Console.WriteLine($"Tag: {tag} Type: {fieldType} NumValues: {numValues} Value: {value}");
}
else
{
long offset = ReadFieldOffset(ifdReader);
ifd.Entries[tag] = new IfdEntry {
Tag = tag, FieldType = fieldType, Offset = offset
};
Console.WriteLine($"Tag: {tag} Type: {fieldType} NumValues: {numValues} Offset: {offset}");
}
}
break;
}
ifdReader.Stream.Position = pos + (_bigTiff ? 8 : 4);
}
if (_bigTiff)
{
ifdOffset = ifdReader.ReadInt64();
}
else
{
ifdOffset = ifdReader.ReadUInt32();
}
}
ifdList.Add(ifd);
}
return(ifdList.ToArray());
}
private object[] ReadFieldValuesAsObjects(BinaryReader2 reader, FieldType fieldType, int numValues)
{
var array = new object[numValues];
switch (fieldType)
{
case FieldType.Int64:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadInt64();
}
}
break;
case FieldType.UInt64:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadInt64();
}
}
break;
case FieldType.Int32:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadInt32();
}
}
break;
case FieldType.UInt32:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadUInt32();
}
}
break;
case FieldType.Int16:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadInt16();
}
}
break;
case FieldType.UInt16:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadUInt16();
}
}
break;
case FieldType.SByte:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadSByte();
}
}
break;
case FieldType.Byte:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadByte();
}
}
break;
case FieldType.Float:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadSingle();
}
}
break;
case FieldType.Double:
{
for (int i = 0; i < numValues; i++)
{
array[i] = reader.ReadDouble();
}
}
break;
case FieldType.Rational:
{
for (int i = 0; i < numValues; i++)
{
array[i] = new Rational(reader.ReadUInt32(), reader.ReadUInt32());
}
}
break;
case FieldType.SRational:
{
for (int i = 0; i < numValues; i++)
{
array[i] = new SRational(reader.ReadInt32(), reader.ReadInt32());
}
}
break;
default:
throw new Exception($"Unknown field type {fieldType}");
}
return(array);
}