static bool TIFFDefaultRefBlackWhite(TIFFDirectory td)
{
if(td.td_photometric==PHOTOMETRIC.YCBCR)
{
// YCbCr (Class Y) images must have the
// ReferenceBlackWhite tag set. Fix the
// broken images, which lacks that tag.
try
{
td.td_refblackwhite=new double[] { 0.0, 255.0, 128.0, 255.0, 128.0, 255.0 };
}
catch
{
return false;
}
}
else
{
try
{
td.td_refblackwhite=new double[6];
}
catch
{
return false;
}
// Assume RGB (Class R)
for(int i=0; i<3; i++)
{
td.td_refblackwhite[2*i+0]=0.0;
td.td_refblackwhite[2*i+1]=(double)((1<<td.td_bitspersample)-1);
}
}
return true;
}
static bool TIFFDefaultTransferFunction(TIFFDirectory td)
{
ushort[][] tf=td.td_transferfunction;
tf[0]=tf[1]=tf[2]=null;
if(td.td_bitspersample>=4*8-2) return false; //4: sizeof(tsize_t)
int n=1<<td.td_bitspersample;
try
{
tf[0]=new ushort[n];
tf[0][0]=0;
for(int i=1; i<n; i++)
{
double t=(double)i/((double)n-1.0);
tf[0][i]=(ushort)Math.Floor(65535*Math.Pow(t, 2.2)+0.5);
}
if(td.td_samplesperpixel-td.td_extrasamples>1)
{
tf[1]=new ushort[n];
tf[2]=new ushort[n];
tf[0].CopyTo(tf[1], 0);
tf[0].CopyTo(tf[2], 0);
}
return true;
}
catch
{
tf[0]=tf[1]=tf[2]=null;
return false;
}
}
// Install extra samples information.
static bool setExtraSamples(TIFFDirectory td, object[] ap, out uint v)
{
v=(uint)__GetAsUint(ap, 0);
if((ushort)v>td.td_samplesperpixel) return false;
Array a=ap[1] as Array;
if(v>1&&a==null) return false; // typically missing param
if(a==null&&v==1)
{
if(!(ap[1] is ushort)) // typically wrong param type, maybe EXTRASAMPLE[]
{
if(!(ap[1] is EXTRASAMPLE)) return false;
EXTRASAMPLE va=(EXTRASAMPLE)ap[1];
ushort[] tmp=new ushort[1];
if(va>EXTRASAMPLE.UNASSALPHA)
{
// XXX: Corel Draw is known to produce incorrect
// ExtraSamples tags which must be patched here if we
// want to be able to open some of the damaged TIFF
// files:
if((int)va==999) va=EXTRASAMPLE.UNASSALPHA;
else return false;
}
tmp[0]=(ushort)va;
td.td_extrasamples=(ushort)v;
TIFFsetShortArray(ref td.td_sampleinfo, tmp, td.td_extrasamples);
}
else
{
ushort[] va=new ushort[1];
va[0]=(ushort)ap[1];
if(va[0]>(ushort)EXTRASAMPLE.UNASSALPHA)
{
// XXX: Corel Draw is known to produce incorrect
// ExtraSamples tags which must be patched here if we
// want to be able to open some of the damaged TIFF
// files:
if(va[0]==999) va[0]=(ushort)EXTRASAMPLE.UNASSALPHA;
else return false;
}
td.td_extrasamples=(ushort)v;
TIFFsetShortArray(ref td.td_sampleinfo, va, td.td_extrasamples);
}
}
else
{
if(!(a is ushort[])) // typically wrong param type, maybe EXTRASAMPLE[]
{
if(!(a is EXTRASAMPLE[])) return false;
EXTRASAMPLE[] va=(EXTRASAMPLE[])a;
ushort[] tmp=new ushort[v];
for(int i=0; i<v; i++)
{
if(va[i]>EXTRASAMPLE.UNASSALPHA)
{
// XXX: Corel Draw is known to produce incorrect
// ExtraSamples tags which must be patched here if we
// want to be able to open some of the damaged TIFF
// files:
if((int)va[i]==999) va[i]=EXTRASAMPLE.UNASSALPHA;
else return false;
}
tmp[i]=(ushort)va[i];
}
td.td_extrasamples=(ushort)v;
TIFFsetShortArray(ref td.td_sampleinfo, tmp, td.td_extrasamples);
}
else
{
ushort[] va=(ushort[])a;
for(int i=0; i<v; i++)
{
if(va[i]>(ushort)EXTRASAMPLE.UNASSALPHA)
{
// XXX: Corel Draw is known to produce incorrect
// ExtraSamples tags which must be patched here if we
// want to be able to open some of the damaged TIFF
// files:
if(va[i]==999) va[i]=(ushort)EXTRASAMPLE.UNASSALPHA;
else return false;
}
}
td.td_extrasamples=(ushort)v;
TIFFsetShortArray(ref td.td_sampleinfo, va, td.td_extrasamples);
}
}
return true;
}
