public PNG_INFO png_get_pCAL(ref string purpose, ref int X0, ref int X1, ref PNG_EQUATION type, ref string units, ref string[] @params)
{
if ((info_ptr_valid & PNG_INFO.pCAL) != PNG_INFO.pCAL)
{
return(PNG_INFO.None);
}
purpose = info_ptr_pcal_purpose;
X0 = info_ptr_pcal_X0;
X1 = info_ptr_pcal_X1;
type = info_ptr_pcal_type;
units = info_ptr_pcal_units;
@params = info_ptr_pcal_params;
return(PNG_INFO.pCAL);
}
public void png_set_pCAL(string purpose, int X0, int X1, PNG_EQUATION type, string units, string[] @params)
{
if (purpose == null || purpose.Length == 0)
{
Debug.WriteLine("Ignoring attempt to set unnamed pCal calibration");
return;
}
info_ptr_pcal_purpose = purpose;
info_ptr_pcal_X0 = X0;
info_ptr_pcal_X1 = X1;
info_ptr_pcal_type = type;
info_ptr_pcal_units = units;
info_ptr_pcal_params = @params; // TODO: params in array must be set to valid parameters
info_ptr_valid |= PNG_INFO.pCAL;
}
public PNG_INFO png_get_pCAL(ref string purpose, ref int X0, ref int X1, ref PNG_EQUATION type, ref string units, ref string[] @params)
{
if((info_ptr_valid&PNG_INFO.pCAL)!=PNG_INFO.pCAL) return PNG_INFO.None;
purpose=info_ptr_pcal_purpose;
X0=info_ptr_pcal_X0;
X1=info_ptr_pcal_X1;
type=info_ptr_pcal_type;
units=info_ptr_pcal_units;
@params=info_ptr_pcal_params;
return PNG_INFO.pCAL;
}
public void png_set_pCAL(string purpose, int X0, int X1, PNG_EQUATION type, string units, string[] @params)
{
if(purpose==null||purpose.Length==0)
{
Debug.WriteLine("Ignoring attempt to set unnamed pCal calibration");
return;
}
info_ptr_pcal_purpose=purpose;
info_ptr_pcal_X0=X0;
info_ptr_pcal_X1=X1;
info_ptr_pcal_type=type;
info_ptr_pcal_units=units;
info_ptr_pcal_params=@params; // TODO: params in array must be set to valid parameters
info_ptr_valid|=PNG_INFO.pCAL;
}
// write the pCAL chunk (described in the PNG extensions document)
void png_write_pCAL(string purpose, int X0, int X1, PNG_EQUATION type, string units, string[] @params)
{
if(units==null||@params==null) return;
if(type>=PNG_EQUATION.LAST) Debug.WriteLine("Unrecognized equation type for pCAL chunk");
byte[] new_purpose=null;
uint purpose_len=png_check_keyword(purpose, ref new_purpose)+1;
uint units_len=(uint)(units.Length+(@params.Length==0?0:1));
uint total_len=purpose_len+units_len+10;
uint[] params_len=new uint[@params.Length];
// Find the length of each parameter, making sure we don't count the
// null terminator for the last parameter.
for(int i=0; i<@params.Length; i++)
{
params_len[i]=(uint)(@params[i].Length+([email protected]?0:1));
total_len+=params_len[i];
}
byte[] buf=new byte[10];
png_write_chunk_start(PNG.pCAL, (uint)total_len);
png_write_chunk_data(new_purpose, purpose_len);
png_save_int_32(buf, X0);
png_save_int_32(buf, 4, X1);
buf[8]=(byte)type;
buf[9]=(byte)@params.Length;
png_write_chunk_data(buf, 10);
png_write_chunk_data(Encoding.ASCII.GetBytes(units), units_len);
new_purpose=null;
for(int i=0; i<@params.Length; i++) png_write_chunk_data(Encoding.ASCII.GetBytes(@params[i]), params_len[i]);
png_write_chunk_end();
}
