//*********************************************************************
//
// Public Routines
//
//*********************************************************************
// Given an open TIFF file, look for GTIF keys and values and return GTIF structure.
//
// This function creates a GeoTIFF information interpretation handle
// (GTIF) based on a passed in TIFF handle originally from
// XTIFFOpen().
//
// The returned GTIF handle can be used to read or write GeoTIFF tags
// using the various GTIF functions. The handle should be destroyed using
// GTIFFree() before the file is closed with TIFFClose().
//
// If the file accessed has no GeoTIFF keys, an valid (but empty) GTIF is
// still returned. GTIFNew() is used both for existing files being read, and
// for new TIFF files that will have GeoTIFF tags written to them.
public static GTIF GTIFNew(TIFF tif)
{
TIFFMethod default_methods=new TIFFMethod();
_GTIFSetDefaultTIFF(default_methods);
return GTIFNewWithMethods(tif, default_methods);
}
//*********************************************************************
//
// Public Routines
//
//*********************************************************************
// Given an open TIFF file, look for GTIF keys and values and return GTIF structure.
//
// This function creates a GeoTIFF information interpretation handle
// (GTIF) based on a passed in TIFF handle originally from
// XTIFFOpen().
//
// The returned GTIF handle can be used to read or write GeoTIFF tags
// using the various GTIF functions. The handle should be destroyed using
// GTIFFree() before the file is closed with TIFFClose().
//
// If the file accessed has no GeoTIFF keys, an valid (but empty) GTIF is
// still returned. GTIFNew() is used both for existing files being read, and
// for new TIFF files that will have GeoTIFF tags written to them.
public static GTIF GTIFNew(TIFF tif)
{
TIFFMethod default_methods = new TIFFMethod();
_GTIFSetDefaultTIFF(default_methods);
return(GTIFNewWithMethods(tif, default_methods));
}
// **************************************************************************
// * GTIFNewWithMethods() *
// * *
// * Create a new geotiff, passing in the methods structure to *
// * support not libtiff implementations without replacing the *
// * default methods. *
// **************************************************************************
public static GTIF GTIFNewWithMethods(TIFF tif, TIFFMethod methods)
{
GTIF gt = null;
try
{
gt = new GTIF();
gt.gt_methods = new TIFFMethod();
gt.gt_keys = new Dictionary <geokey_t, GeoKey>();
}
catch
{
return(null);
}
// install TIFF file and I/O methods
gt.gt_tif = tif;
gt.gt_methods.get = methods.get;
gt.gt_methods.set = methods.set;
gt.gt_methods.type = methods.type;
gt.gt_rev_major = GvCurrentRevision;
gt.gt_rev_minor = GvCurrentMinorRev;
gt.gt_version = GvCurrentVersion;
if (tif == null)
{
return(gt);
}
object data;
int nshorts;
// since this is an array, GTIF will allocate the memory
if (!gt.gt_methods.get(tif, (ushort)GTIFF_GEOKEYDIRECTORY, out nshorts, out data))
{
return(gt);
}
if (nshorts < 4)
{
return(null);
}
ushort[] shorts = data as ushort[];
if (shorts == null || shorts.Length < 4)
{
return(null);
}
if (shorts[0] > GvCurrentVersion)
{
return(null);
}
gt.gt_version = shorts[0];
if (shorts[1] > GvCurrentRevision)
{
// issue warning
}
gt.gt_rev_major = shorts[1];
gt.gt_rev_minor = shorts[2];
int count = shorts[3];
if (count == 0)
{
return(gt);
}
if (shorts.Length < (count * 4 + 4))
{
return(null);
}
// If we got here, then the geokey can be parsed
// Get the PARAMS Tags, if any
int ndoubles;
double[] doubles;
if (!gt.gt_methods.get(tif, (ushort)GTIFF_DOUBLEPARAMS, out ndoubles, out data))
{
try
{
doubles = new double[MAX_VALUES];
}
catch
{
return(null);
}
}
else
{
doubles = data as double[];
if (doubles == null)
{
return(null);
}
}
int stringsLength = 0;
string strings = null;
if (gt.gt_methods.get(tif, (ushort)GTIFF_ASCIIPARAMS, out stringsLength, out data))
{
strings = data as string;
if (strings == null)
{
return(null);
}
strings = strings.TrimEnd('\0'); // last NULL doesn't count; "|" used for delimiter
stringsLength = strings.Length;
}
for (int i = 0; i < count; i++)
{
ushort KeyID = shorts[i * 4 + 4];
ushort TIFFTagLocation = shorts[i * 4 + 5];
ushort Count = shorts[i * 4 + 6];
ushort Value_Offset = shorts[i * 4 + 7];
GeoKey keyptr;
try
{
keyptr = new GeoKey();
keyptr.gk_key = (geokey_t)KeyID;
if (TIFFTagLocation != 0)
{
keyptr.gk_type = gt.gt_methods.type(gt.gt_tif, TIFFTagLocation);
}
else
{
keyptr.gk_type = tagtype_t.TYPE_SHORT; //gt.gt_methods.type(gt.gt_tif, (ushort)GTIFF_GEOKEYDIRECTORY);
}
switch (TIFFTagLocation)
{
case (ushort)GTIFF_LOCAL:
// store value into data value
keyptr.gk_data = new ushort[] { Value_Offset };
keyptr.gk_count = 1;
break;
case (ushort)GTIFF_GEOKEYDIRECTORY:
ushort[] s = new ushort[Count];
keyptr.gk_data = s;
Array.Copy(shorts, Value_Offset, s, 0, Count);
keyptr.gk_count = Count;
break;
case (ushort)GTIFF_DOUBLEPARAMS:
double[] d = new double[Count];
keyptr.gk_data = d;
Array.Copy(doubles, Value_Offset, d, 0, Count);
keyptr.gk_count = Count;
break;
case (ushort)GTIFF_ASCIIPARAMS:
string str = strings.Substring(Value_Offset, Count);
str = str.Replace('|', '\0');
str = str.Trim('\0');
keyptr.gk_count = str.Length;
keyptr.gk_data = str;
break;
default:
return(null); // failure
}
}
catch
{
return(null);
}
gt.gt_keys.Add(keyptr.gk_key, keyptr);
}
return(gt);
}
// **************************************************************************
// * GTIFNewWithMethods() *
// * *
// * Create a new geotiff, passing in the methods structure to *
// * support not libtiff implementations without replacing the *
// * default methods. *
// **************************************************************************
public static GTIF GTIFNewWithMethods(TIFF tif, TIFFMethod methods)
{
GTIF gt=null;
try
{
gt=new GTIF();
gt.gt_methods=new TIFFMethod();
gt.gt_keys=new Dictionary<geokey_t, GeoKey>();
}
catch
{
return null;
}
// install TIFF file and I/O methods
gt.gt_tif=tif;
gt.gt_methods.get=methods.get;
gt.gt_methods.set=methods.set;
gt.gt_methods.type=methods.type;
gt.gt_rev_major=GvCurrentRevision;
gt.gt_rev_minor=GvCurrentMinorRev;
gt.gt_version=GvCurrentVersion;
if(tif==null) return gt;
object data;
int nshorts;
// since this is an array, GTIF will allocate the memory
if(!gt.gt_methods.get(tif, (ushort)GTIFF_GEOKEYDIRECTORY, out nshorts, out data)) return gt;
if(nshorts<4) return null;
ushort[] shorts=data as ushort[];
if(shorts==null||shorts.Length<4) return null;
if(shorts[0]>GvCurrentVersion) return null;
gt.gt_version=shorts[0];
if(shorts[1]>GvCurrentRevision)
{
// issue warning
}
gt.gt_rev_major=shorts[1];
gt.gt_rev_minor=shorts[2];
int count=shorts[3];
if(count==0) return gt;
if(shorts.Length<(count*4+4)) return null;
// If we got here, then the geokey can be parsed
// Get the PARAMS Tags, if any
int ndoubles;
double[] doubles;
if(!gt.gt_methods.get(tif, (ushort)GTIFF_DOUBLEPARAMS, out ndoubles, out data))
{
try
{
doubles=new double[MAX_VALUES];
}
catch
{
return null;
}
}
else
{
doubles=data as double[];
if(doubles==null) return null;
}
int stringsLength=0;
string strings=null;
if(gt.gt_methods.get(tif, (ushort)GTIFF_ASCIIPARAMS, out stringsLength, out data))
{
strings=data as string;
if(strings==null) return null;
strings=strings.TrimEnd('\0'); // last NULL doesn't count; "|" used for delimiter
stringsLength=strings.Length;
}
for(int i=0; i<count; i++)
{
ushort KeyID=shorts[i*4+4];
ushort TIFFTagLocation=shorts[i*4+5];
ushort Count=shorts[i*4+6];
ushort Value_Offset=shorts[i*4+7];
GeoKey keyptr;
try
{
keyptr=new GeoKey();
keyptr.gk_key=(geokey_t)KeyID;
if(TIFFTagLocation!=0) keyptr.gk_type=gt.gt_methods.type(gt.gt_tif, TIFFTagLocation);
else keyptr.gk_type=tagtype_t.TYPE_SHORT; //gt.gt_methods.type(gt.gt_tif, (ushort)GTIFF_GEOKEYDIRECTORY);
switch(TIFFTagLocation)
{
case (ushort)GTIFF_LOCAL:
// store value into data value
keyptr.gk_data=new ushort[] { Value_Offset };
keyptr.gk_count=1;
break;
case (ushort)GTIFF_GEOKEYDIRECTORY:
ushort[] s=new ushort[Count];
keyptr.gk_data=s;
Array.Copy(shorts, Value_Offset, s, 0, Count);
keyptr.gk_count=Count;
break;
case (ushort)GTIFF_DOUBLEPARAMS:
double[] d=new double[Count];
keyptr.gk_data=d;
Array.Copy(doubles, Value_Offset, d, 0, Count);
keyptr.gk_count=Count;
break;
case (ushort)GTIFF_ASCIIPARAMS:
string str=strings.Substring(Value_Offset, Count);
str=str.Replace('|', '\0');
str=str.Trim('\0');
keyptr.gk_count=str.Length;
keyptr.gk_data=str;
break;
default:
return null; // failure
}
}
catch
{
return null;
}
gt.gt_keys.Add(keyptr.gk_key, keyptr);
}
return gt;
}
