private static void readDirEntry(TiffDirEntry[] dir, ulong dircount, byte[] bytes, int offset, bool isBigTiff)
{
int pos = offset;
for (ulong i = 0; i < dircount; i++)
{
TiffDirEntry entry = new TiffDirEntry();
entry.tdir_tag = (TiffTag)(ushort)readShort(bytes, pos);
pos += sizeof(short);
entry.tdir_type = (TiffType)readShort(bytes, pos);
pos += sizeof(short);
if (isBigTiff)
{
entry.tdir_count = (int)readULong(bytes, pos);
pos += sizeof(ulong);
entry.tdir_offset = readULong(bytes, pos);
pos += sizeof(ulong);
}
else
{
entry.tdir_count = (int)readInt(bytes, pos);
pos += sizeof(int);
entry.tdir_offset = (ulong)(uint)readInt(bytes, pos);
pos += sizeof(int);
}
dir[i] = entry;
}
}
/// <summary>
/// Fetches an array of FLOAT values.
/// </summary>
private bool fetchFloatArray(TiffDirEntry dir, float[] v)
{
if (dir.tdir_count == 1)
{
v[0] = BitConverter.ToSingle(BitConverter.GetBytes(dir.tdir_offset), 0);
return(true);
}
int w = DataWidth(dir.tdir_type);
int cc = dir.tdir_count * w;
byte[] b = new byte [cc];
int read = fetchData(dir, b);
if (read != 0)
{
int byteOffset = 0;
for (int i = 0; i < read / 4; i++)
{
v[i] = BitConverter.ToSingle(b, byteOffset);
byteOffset += 4;
}
}
return(read != 0);
}
/// <summary>
/// Setups a SHORT directory entry
/// </summary>
private void setupShort(TiffTag tag, ref TiffDirEntry dir, short v)
{
dir.tdir_tag = tag;
dir.tdir_count = 1;
dir.tdir_type = TiffType.SHORT;
dir.tdir_offset = insertData(TiffType.SHORT, v);
}
/*
* Fetch and set the SubjectDistance EXIF tag.
*/
private bool fetchSubjectDistance(TiffDirEntry dir)
{
if (dir.tdir_count != 1 || dir.tdir_type != TiffType.RATIONAL)
{
Tiff.WarningExt(this, m_clientdata, m_name,
"incorrect count or type for SubjectDistance, tag ignored");
return(false);
}
bool ok = false;
byte[] b = new byte[2 * sizeof(int)];
int read = fetchData(dir, b);
if (read != 0)
{
int[] l = new int[2];
l[0] = readInt(b, 0);
l[1] = readInt(b, sizeof(int));
float v;
if (cvtRational(dir, l[0], l[1], out v))
{
/*
* XXX: Numerator -1 means that we have infinite
* distance. Indicate that with a negative floating point
* SubjectDistance value.
*/
ok = SetField(dir.tdir_tag, (l[0] != -1) ? v : -v);
}
}
return(ok);
}
/// <summary>
/// Setup a directory entry of an array of SHORT or SSHORT and write
/// the associated indirect values.
/// </summary>
private bool writeShortArray(ref TiffDirEntry dir, short[] v)
{
if (dir.tdir_count <= 2)
{
if (m_header.tiff_magic == TIFF_BIGENDIAN)
{
dir.tdir_offset = (uint)(v[0] << 16);
if (dir.tdir_count == 2)
{
dir.tdir_offset |= (uint)(v[1] & 0xffff);
}
}
else
{
dir.tdir_offset = (uint)(v[0] & 0xffff);
if (dir.tdir_count == 2)
{
dir.tdir_offset |= (uint)(v[1] << 16);
}
}
return(true);
}
return(writeData(ref dir, v, dir.tdir_count));
}
private bool writeTransferFunction(ref TiffDirEntry dir)
{
// Check if the table can be written as a single column, or if it
// must be written as 3 columns. Note that we write a 3-column tag
// if there are 2 samples/pixel and a single column of data
// won't suffice--hmm.
int u = m_dir.td_samplesperpixel - m_dir.td_extrasamples;
int ncols = 1;
bool reCheck = false;
int n = 1 << m_dir.td_bitspersample;
if (u < 0 || u > 2)
{
if (Compare(m_dir.td_transferfunction[0], m_dir.td_transferfunction[2], n) != 0)
{
ncols = 3;
}
else
{
reCheck = true;
}
}
if (u == 2 || reCheck)
{
if (Compare(m_dir.td_transferfunction[0], m_dir.td_transferfunction[1], n) != 0)
{
ncols = 3;
}
}
return(writeShortTable(TiffTag.TRANSFERFUNCTION, ref dir, ncols, m_dir.td_transferfunction));
}
/// <summary>
/// Fetch an array of RATIONAL or SRATIONAL values.
/// </summary>
private bool fetchRationalArray(TiffDirEntry dir, float[] v)
{
Debug.Assert(sizeof(float) == sizeof(int));
bool ok = false;
byte[] l = new byte [dir.tdir_count * DataWidth(dir.tdir_type)];
if (fetchData(dir, l) != 0)
{
int offset = 0;
int[] pair = new int[2];
for (int i = 0; i < dir.tdir_count; i++)
{
pair[0] = readInt(l, offset);
offset += sizeof(int);
pair[1] = readInt(l, offset);
offset += sizeof(int);
ok = cvtRational(dir, pair[0], pair[1], out v[i]);
if (!ok)
{
break;
}
}
}
return(ok);
}
/*
* Fetch a pair of SHORT or BYTE values. Some tags may have either BYTE
* or SHORT type and this function works with both ones.
*/
private bool fetchShortPair(TiffDirEntry dir)
{
/*
* Prevent overflowing arrays below by performing a sanity
* check on tdir_count, this should never be greater than two.
*/
if (dir.tdir_count > 2)
{
WarningExt(this, m_clientdata, m_name,
"unexpected count for field \"{0}\", {1}, expected 2; ignored",
FieldWithTag(dir.tdir_tag).Name, dir.tdir_count);
return(false);
}
switch (dir.tdir_type)
{
case TiffType.BYTE:
case TiffType.SBYTE:
byte[] bytes = new byte[4];
return(fetchByteArray(dir, bytes) && SetField(dir.tdir_tag, bytes[0], bytes[1]));
case TiffType.SHORT:
case TiffType.SSHORT:
short[] shorts = new short[2];
return(fetchShortArray(dir, shorts) && SetField(dir.tdir_tag, shorts[0], shorts[1]));
}
return(false);
}
private bool writeInkNames(ref TiffDirEntry dir)
{
dir.tdir_tag = TiffTag.INKNAMES;
dir.tdir_type = TiffType.ASCII;
byte[] bytes = Latin1Encoding.GetBytes(m_dir.td_inknames);
dir.tdir_count = bytes.Length;
return(writeByteArray(ref dir, bytes));
}
/// <summary>
/// Fetches an array of BYTE or SBYTE values.
/// </summary>
private bool fetchByteArray(TiffDirEntry dir, byte[] v)
{
if (dir.tdir_count <= 4)
{
// Extract data from offset field.
int count = dir.tdir_count;
if (m_header.tiff_magic == TIFF_BIGENDIAN)
{
if (count == 4)
{
v[3] = (byte)(dir.tdir_offset & 0xff);
}
if (count >= 3)
{
v[2] = (byte)((dir.tdir_offset >> 8) & 0xff);
}
if (count >= 2)
{
v[1] = (byte)((dir.tdir_offset >> 16) & 0xff);
}
if (count >= 1)
{
v[0] = (byte)(dir.tdir_offset >> 24);
}
}
else
{
if (count == 4)
{
v[3] = (byte)(dir.tdir_offset >> 24);
}
if (count >= 3)
{
v[2] = (byte)((dir.tdir_offset >> 16) & 0xff);
}
if (count >= 2)
{
v[1] = (byte)((dir.tdir_offset >> 8) & 0xff);
}
if (count >= 1)
{
v[0] = (byte)(dir.tdir_offset & 0xff);
}
}
return(true);
}
return(fetchData(dir, v) != 0);
}
/// <summary>
/// Fetches a contiguous directory item.
/// </summary>
private int fetchData(TiffDirEntry dir, byte[] buffer)
{
int width = DataWidth(dir.tdir_type);
int count = (int)dir.tdir_count * width;
// Check for overflow.
if (dir.tdir_count == 0 || width == 0 || (count / width) != dir.tdir_count)
{
fetchFailed(dir);
}
if (!seekOK(dir.tdir_offset))
{
fetchFailed(dir);
}
if (!readOK(buffer, count))
{
fetchFailed(dir);
}
if ((m_flags & TiffFlags.SWAB) == TiffFlags.SWAB)
{
switch (dir.tdir_type)
{
case TiffType.SHORT:
case TiffType.SSHORT:
short[] s = ByteArrayToShorts(buffer, 0, count);
SwabArrayOfShort(s, dir.tdir_count);
ShortsToByteArray(s, 0, dir.tdir_count, buffer, 0);
break;
case TiffType.LONG:
case TiffType.SLONG:
case TiffType.FLOAT:
case TiffType.IFD:
int[] l = ByteArrayToInts(buffer, 0, count);
SwabArrayOfLong(l, dir.tdir_count);
IntsToByteArray(l, 0, dir.tdir_count, buffer, 0);
break;
case TiffType.RATIONAL:
case TiffType.SRATIONAL:
int[] r = ByteArrayToInts(buffer, 0, count);
SwabArrayOfLong(r, 2 * dir.tdir_count);
IntsToByteArray(r, 0, 2 * dir.tdir_count, buffer, 0);
break;
case TiffType.DOUBLE:
swab64BitData(buffer, 0, count);
break;
}
}
return(count);
}
/// <summary>
/// Setup a directory entry of an array of LONG or SLONG and write the
/// associated indirect values.
/// </summary>
private bool writeLongArray(ref TiffDirEntry dir, int[] v)
{
if (dir.tdir_count == 1)
{
dir.tdir_offset = (uint)v[0];
return(true);
}
return(writeData(ref dir, v, dir.tdir_count));
}
private bool writeFloatArray(ref TiffDirEntry dir, float[] v)
{
if (dir.tdir_count == 1)
{
dir.tdir_offset = BitConverter.ToUInt32(BitConverter.GetBytes(v[0]), 0);
return(true);
}
return(writeData(ref dir, v, dir.tdir_count));
}
private bool writeData(ref TiffDirEntry dir, float[] cp, int cc)
{
int[] ints = new int[cc];
for (int i = 0; i < cc; i++)
{
byte[] result = BitConverter.GetBytes(cp[i]);
ints[i] = BitConverter.ToInt32(result, 0);
}
return(writeData(ref dir, ints, cc));
}
/// <summary>
/// Reads IFD structure from the specified offset.
/// </summary>
/// <returns>The number of fields in the directory or 0 if failed.</returns>
private short fetchDirectory(uint diroff, out TiffDirEntry[] pdir, out uint nextdiroff)
{
const string module = "fetchDirectory";
m_diroff = diroff;
nextdiroff = 0;
short dircount;
TiffDirEntry[] dir = null;
pdir = null;
if (!seekOK(m_diroff))
{
ErrorExt(this, m_clientdata, module,
"{0}: Seek error accessing TIFF directory", m_name);
return(0);
}
if (!readShortOK(out dircount))
{
ErrorExt(this, m_clientdata, module,
"{0}: Can not read TIFF directory count", m_name);
return(0);
}
if ((m_flags & TiffFlags.SWAB) == TiffFlags.SWAB)
{
SwabShort(ref dircount);
}
dir = new TiffDirEntry [dircount];
if (!readDirEntryOk(dir, dircount))
{
ErrorExt(this, m_clientdata, module, "{0}: Can not read TIFF directory", m_name);
return(0);
}
// Read offset to next directory for sequential scans.
int temp;
readIntOK(out temp);
nextdiroff = (uint)temp;
if ((m_flags & TiffFlags.SWAB) == TiffFlags.SWAB)
{
temp = (int)nextdiroff;
SwabLong(ref temp);
nextdiroff = (uint)temp;
}
pdir = dir;
return(dircount);
}
private int extractData(TiffDirEntry dir)
{
int type = (int)dir.tdir_type;
if (m_header.tiff_magic == TIFF_BIGENDIAN)
{
return((int)((dir.tdir_offset >> m_typeshift[type]) & m_typemask[type]));
}
return((int)(dir.tdir_offset & m_typemask[type]));
}
/*
* Setup a pair of shorts that are returned by
* value, rather than as a reference to an array.
*/
private bool setupShortPair(TiffTag tag, ref TiffDirEntry dir)
{
short[] v = new short[2];
FieldValue[] result = GetField(tag);
v[0] = result[0].ToShort();
v[1] = result[1].ToShort();
dir.tdir_tag = tag;
dir.tdir_type = TiffType.SHORT;
dir.tdir_count = 2;
return(writeShortArray(ref dir, v));
}
private bool writeData(ref TiffDirEntry dir, double[] buffer, int count)
{
if ((m_flags & TiffFlags.SWAB) == TiffFlags.SWAB)
{
SwabArrayOfDouble(buffer, count);
}
byte[] bytes = new byte[count * sizeof(double)];
Buffer.BlockCopy(buffer, 0, bytes, 0, bytes.Length);
return(writeData(ref dir, bytes, count * sizeof(double)));
}
private bool writeData(ref TiffDirEntry dir, short[] buffer, int count)
{
if ((m_flags & TiffFlags.SWAB) == TiffFlags.SWAB)
{
SwabArrayOfShort(buffer, count);
}
int byteCount = count * sizeof(short);
byte[] bytes = new byte [byteCount];
ShortsToByteArray(buffer, 0, count, bytes, 0);
return(writeData(ref dir, bytes, byteCount));
}
/// <summary>
/// Fetches a set of offsets or lengths.
/// </summary>
/// <remarks>While this routine says "strips", in fact it's also used
/// for tiles.</remarks>
private bool fetchStripThing(TiffDirEntry dir, int nstrips, ref int[] lpp)
{
checkDirCount(dir, nstrips);
// Allocate space for strip information.
if (lpp == null)
{
lpp = new int [nstrips];
}
else
{
Array.Clear(lpp, 0, lpp.Length);
}
bool status = false;
if (dir.tdir_type == TiffType.SHORT)
{
// Handle short -> int expansion.
short[] dp = new short[dir.tdir_count];
status = fetchShortArray(dir, dp);
if (status)
{
for (int i = 0; i < nstrips && i < dir.tdir_count; i++)
{
lpp[i] = dp[i];
}
}
}
else if (nstrips != dir.tdir_count)
{
// Special case to correct length
int[] dp = new int[dir.tdir_count];
status = fetchLongArray(dir, dp);
if (status)
{
for (int i = 0; i < nstrips && i < dir.tdir_count; i++)
{
lpp[i] = dp[i];
}
}
}
else
{
status = fetchLongArray(dir, lpp);
}
return(status);
}
/// <summary>
/// Advance to next tiff directory within file
/// </summary>
/// <param name="nextdir">Start location of next directory to try and advance to
/// This will be updated with location of next directory if found</param>
/// <param name="off">Offset of the end of the directory, right before the offset of the following directory is given</param>
/// <param name="dircount">Numbers of directories in this IFD</param>
/// <returns>True if next directory was found and nextdir was updated</returns>
private bool advanceDirectory(ref ulong nextdir, out long off, out ulong dircount)
{
off = 0;
dircount = 0;
const string module = "advanceDirectory";
//Number of directories in this header
if (!seekOK((long)nextdir) || !readDirCountOK(out dircount, m_header.tiff_version == TIFF_BIGTIFF_VERSION))
{
ErrorExt(this, m_clientdata, module, "{0}: Error fetching directory count", m_name);
return(false);
}
if ((m_flags & TiffFlags.SWAB) == TiffFlags.SWAB)
{
SwabBigTiffValue(ref dircount, m_header.tiff_version == TIFF_BIGTIFF_VERSION, true);
}
//The location of the end of the directory
off = (long)seekFile((long)dircount * TiffDirEntry.SizeInBytes(m_header.tiff_version == TIFF_BIGTIFF_VERSION), SeekOrigin.Current);
if (m_header.tiff_version == TIFF_BIGTIFF_VERSION)
{
if (!readUlongOK(out nextdir))
{
ErrorExt(this, m_clientdata, module, "{0}: Error fetching directory link", m_name);
return(false);
}
}
else
{
//Get start location of next directory
uint tempNextDir;
if (!readUIntOK(out tempNextDir))
{
ErrorExt(this, m_clientdata, module, "{0}: Error fetching directory link", m_name);
return(false);
}
nextdir = tempNextDir;
}
if ((m_flags & TiffFlags.SWAB) == TiffFlags.SWAB)
{
SwabBigTiffValue(ref nextdir, m_header.tiff_version == TIFF_BIGTIFF_VERSION, false);
}
return(true);
}
/// <summary>
/// Setups a directory entry with either a SHORT or LONG type
/// according to the value.
/// </summary>
private void setupShortLong(TiffTag tag, ref TiffDirEntry dir, int v)
{
dir.tdir_tag = tag;
dir.tdir_count = 1;
if (v > 0xffffL)
{
dir.tdir_type = TiffType.LONG;
dir.tdir_offset = (uint)v;
}
else
{
dir.tdir_type = TiffType.SHORT;
dir.tdir_offset = insertData(TiffType.SHORT, v);
}
}
private bool writeRational(TiffType type, TiffTag tag, ref TiffDirEntry dir, float v)
{
dir.tdir_tag = tag;
dir.tdir_type = type;
dir.tdir_count = 1;
float[] a = new float[1];
a[0] = v;
if (!writeRationalArray(ref dir, a))
{
return(false);
}
return(true);
}
/// <summary>
/// Writes a contiguous directory item.
/// </summary>
private bool writeData(ref TiffDirEntry dir, byte[] buffer, int count)
{
dir.tdir_offset = m_dataoff;
count = (int)dir.tdir_count * DataWidth(dir.tdir_type);
if (seekOK(dir.tdir_offset) && writeOK(buffer, 0, count))
{
m_dataoff += (uint)((count + 1) & ~1);
return(true);
}
ErrorExt(this, m_clientdata, m_name,
"Error writing data for field \"{0}\"",
FieldWithTag(dir.tdir_tag).Name);
return(false);
}
private bool writeData(ref TiffDirEntry dir, int[] cp, int cc)
{
if ((m_flags & TiffFlags.SWAB) == TiffFlags.SWAB)
{
SwabArrayOfLong(cp, cc);
}
int byteCount = cc * sizeof(int);
byte[] bytes = new byte [byteCount];
IntsToByteArray(cp, 0, cc, bytes, 0);
bool res = writeData(ref dir, bytes, byteCount);
return(res);
}
/*
* Setup a directory entry that references a samples/pixel array of ``type''
* values and (potentially) write the associated indirect values. The source
* data from GetField() for the specified tag must be returned as double.
*/
private bool writePerSampleAnys(TiffType type, TiffTag tag, ref TiffDirEntry dir)
{
double[] w = new double [m_dir.td_samplesperpixel];
FieldValue[] result = GetField(tag);
double v = result[0].ToDouble();
for (short i = 0; i < m_dir.td_samplesperpixel; i++)
{
w[i] = v;
}
bool status = writeAnyArray(type, tag, ref dir, m_dir.td_samplesperpixel, w);
return(status);
}
/*
* Convert numerator+denominator to float.
*/
private bool cvtRational(TiffDirEntry dir, int num, int denom, out float rv)
{
if (denom == 0)
{
ErrorExt(this, m_clientdata, m_name,
"{0}: Rational with zero denominator (num = {1})",
FieldWithTag(dir.tdir_tag).Name, num);
rv = float.NaN;
return(false);
}
else
{
rv = ((float)num / (float)denom);
return(true);
}
}
/// <summary>
/// Write/copy data associated with an ASCII or opaque tag value.
/// </summary>
private bool writeByteArray(ref TiffDirEntry dir, byte[] cp)
{
if (dir.tdir_count <= 4)
{
if (m_header.tiff_magic == TIFF_BIGENDIAN)
{
dir.tdir_offset = (uint)(cp[0] << 24);
if (dir.tdir_count >= 2)
{
dir.tdir_offset |= (uint)(cp[1] << 16);
}
if (dir.tdir_count >= 3)
{
dir.tdir_offset |= (uint)(cp[2] << 8);
}
if (dir.tdir_count == 4)
{
dir.tdir_offset |= cp[3];
}
}
else
{
dir.tdir_offset = cp[0];
if (dir.tdir_count >= 2)
{
dir.tdir_offset |= (uint)(cp[1] << 8);
}
if (dir.tdir_count >= 3)
{
dir.tdir_offset |= (uint)(cp[2] << 16);
}
if (dir.tdir_count == 4)
{
dir.tdir_offset |= (uint)(cp[3] << 24);
}
}
return(true);
}
return(writeData(ref dir, cp, dir.tdir_count));
}
/// <summary>
/// Fetches and sets the RefBlackWhite tag.
/// </summary>
private bool fetchRefBlackWhite(TiffDirEntry dir)
{
// some OJPEG images specify Reference BlackWhite as array of longs
//
// so, we'll try to read value as float array and check them
// if read was successfull and there is at least one value greater
// then 1.0 then ok, return value just read.
//
// if read failed or all values are less then or equal to 1.0 then
// try once again but read as long array this time.
if (dir.tdir_type == TiffType.RATIONAL)
{
bool res = fetchNormalTag(dir);
if (res)
{
for (int i = 0; i < m_dir.td_refblackwhite.Length; i++)
{
if (m_dir.td_refblackwhite[i] > 1)
{
return(true);
}
}
}
}
// Handle LONG's for backward compatibility.
dir.tdir_type = TiffType.LONG;
int[] cp = new int [dir.tdir_count];
bool ok = fetchLongArray(dir, cp);
dir.tdir_type = TiffType.RATIONAL;
if (ok)
{
float[] fp = new float [dir.tdir_count];
for (int i = 0; i < dir.tdir_count; i++)
{
fp[i] = (float)cp[i];
}
ok = SetField(dir.tdir_tag, fp);
}
return(ok);
}
/// <summary>
/// Fetch an array of SHORT or SSHORT values.
/// </summary>
private bool fetchShortArray(TiffDirEntry dir, short[] v)
{
if (dir.tdir_count <= 2)
{
int count = dir.tdir_count;
if (m_header.tiff_magic == TIFF_BIGENDIAN)
{
if (count == 2)
{
v[1] = (short)(dir.tdir_offset & 0xffff);
}
if (count >= 1)
{
v[0] = (short)(dir.tdir_offset >> 16);
}
}
else
{
if (count == 2)
{
v[1] = (short)(dir.tdir_offset >> 16);
}
if (count >= 1)
{
v[0] = (short)(dir.tdir_offset & 0xffff);
}
}
return(true);
}
int cc = dir.tdir_count * sizeof(short);
byte[] b = new byte[cc];
int read = fetchData(dir, b);
if (read != 0)
{
Buffer.BlockCopy(b, 0, v, 0, b.Length);
}
return(read != 0);
}
