Resolve "Update: GDF Writer header"

Closes #193 (closed)

plugins/processing/file-io/src/box-algorithms/ovpCGDFFileWriter.cpp

@@ -37,11 +37,11 @@ void CGDFFileWriter::setChannelName(const size_t index, const char* name)
 
 	m_variableHeader[index].m_ChannelType          = 17;  //float64
 	m_variableHeader[index].m_NSamplesInEachRecord = 1;
-	// No need for scaling on 8 bytes channel type. The following values will generate a scale of 1.0 and offset of 0.0.
-	m_variableHeader[index].m_PhysicalMin          = 0.0;
-	m_variableHeader[index].m_PhysicalMax          = 1.0;
-	m_variableHeader[index].m_DigitalMin           = 0;
-	m_variableHeader[index].m_DigitalMax           = 1;
+	// This scaling values are maxed and not representative of the signal, because values are stored as doubles and not limited in precision.
+	m_variableHeader[index].m_PhysicalMin          = std::numeric_limits<float>::lowest()/2;
+	m_variableHeader[index].m_PhysicalMax          = std::numeric_limits<float>::max()/2;
+	m_variableHeader[index].m_DigitalMin           = std::numeric_limits<int64_t>::lowest()/2;
+	m_variableHeader[index].m_DigitalMax           = std::numeric_limits<int64_t>::max()/2;
 
 	m_channelScale[index] = (m_variableHeader[index].m_PhysicalMax - m_variableHeader[index].m_PhysicalMin) / static_cast<double>(m_variableHeader[index].m_DigitalMax - m_variableHeader[index].m_DigitalMin);
 	m_channelOffset[index] = m_variableHeader[index].m_PhysicalMin - m_channelScale[index] * static_cast<double>(m_variableHeader[index].m_DigitalMin);