Add support for FITSKeywords

.gitignore

@@ -37,6 +37,7 @@ Thumbs.db
 
 # qtcreator generated files
 *.pro.user*
+CMakeLists.txt.user
 
 # xemacs temporary files
 *.flc
@@ -71,3 +72,4 @@ Thumbs.db
 *.dll
 *.exe
 
+/build*

libxisf.cpp

@@ -410,6 +410,8 @@ void XISFReader::readImageElement()
         {
             if(_xml->name() == "Property")
                 image.properties.push_back(readPropertyElement());
+            else if(_xml->name() == "FITSKeyword")
+                image.fitsKeywords.push_back(readFITSKeyword());
             else if(_xml->name() == "ICCProfile")
             {
                 DataBlock icc = readDataBlock();
@@ -442,6 +444,15 @@ Property XISFReader::readPropertyElement()
     return property;
 }
 
+FITSKeyword XISFReader::readFITSKeyword()
+{
+    QXmlStreamAttributes attributes = _xml->attributes();
+    if(attributes.hasAttribute("name") && attributes.hasAttribute("value") && attributes.hasAttribute("comment"))
+        return { attributes.value("name").toString(), attributes.value("value").toString(), attributes.value("comment").toString() };
+    else
+        throw Error("Invalid FITSKeyword element");
+}
+
 void XISFReader::readDataElement(DataBlock &dataBlock)
 {
     _xml->readNextStartElement();
@@ -552,15 +563,6 @@ void XISFWriter::save(QIODevice &io)
     }
 }
 
-void XISFWriter::saveXML(const QString &name)
-{
-    QFile fw(name);
-    fw.open(QIODevice::WriteOnly);
-    QByteArray header = _xisfHeader.mid(16);
-    header.truncate(header.indexOf('\0'));
-    fw.write(header);
-}
-
 void XISFWriter::writeImage(const Image &image)
 {
     _images.push_back(image);
@@ -633,6 +635,9 @@ void XISFWriter::writeImageElement(const Image &image)
     for(auto &property : image.properties)
         writePropertyElement(property);
 
+    for(auto &fitsKeyword : image.fitsKeywords)
+        writeFITSKeyword(fitsKeyword);
+
     _xml->writeEndElement();
 }
 
@@ -703,6 +708,16 @@ void XISFWriter::writePropertyElement(const Property &property)
         throw Error("Failed to write property");
 }
 
+void XISFWriter::writeFITSKeyword(const FITSKeyword &keyword)
+{
+    _xml->writeEmptyElement("FITSKeyword");
+    _xml->writeAttribute("name", keyword.name);
+    _xml->writeAttribute("value", keyword.value);
+    _xml->writeAttribute("comment", keyword.comment);
+    if(_xml->hasError())
+        throw Error("Failed to write FITS keyword");
+}
+
 void XISFWriter::writeMetadata()
 {
     _xml->writeStartElement("Metadata");

libxisf.h

@@ -66,6 +66,13 @@ struct Property
         value(QVariant::fromValue<T>(_value)){}
 };
 
+struct FITSKeyword
+{
+    QString name;
+    QString value;
+    QString comment;
+};
+
 struct Image
 {
     enum Type
@@ -119,6 +126,7 @@ struct Image
     DataBlock dataBlock;
     QByteArray iccProfile;
     std::vector<Property> properties;
+    std::vector<FITSKeyword> fitsKeywords;
 
     void convertPixelStorageTo(PixelStorage storage);
 
@@ -138,7 +146,7 @@ public:
     XISFReader();
     void open(const QString &name);
     void open(const QByteArray &data);
-    /** Open image from */
+    /** Open image from QIODevice. This method takes ownership of *io pointer */
     void open(QIODevice *io);
     void close();
     int imagesCount() const;
@@ -148,6 +156,7 @@ private:
     void readSignature();
     void readImageElement();
     Property readPropertyElement();
+    FITSKeyword readFITSKeyword();
     void readDataElement(DataBlock &dataBlock);
     DataBlock readDataBlock();
     void readCompression(DataBlock &dataBlock);
@@ -165,7 +174,6 @@ public:
     void save(const QString &name);
     void save(QByteArray &data);
     void save(QIODevice &io);
-    void saveXML(const QString &name);
     void writeImage(const Image &image);
 private:
     void writeHeader();
@@ -173,6 +181,7 @@ private:
     void writeDataBlockAttributes(const DataBlock &dataBlock);
     void writeCompressionAttributes(const DataBlock &dataBlock);
     void writePropertyElement(const Property &property);
+    void writeFITSKeyword(const FITSKeyword &keyword);
     void writeMetadata();
     std::unique_ptr<QXmlStreamWriter> _xml;
     QByteArray _xisfHeader;

test/main.cpp

@@ -47,6 +47,8 @@ int main(int argc, char **argv)
             image.properties.push_back(Property("PropertyFloat64", (Float64) 0.64));
             image.properties.push_back(Property("PropertyComplex32", Complex32{3.0, -2.0}));
             image.properties.push_back(Property("PropertyComplex64", Complex64{-3.0, 2.0}));
+            image.fitsKeywords.push_back({"RA", "226.9751163116387", "Right ascension of the center of the image (deg)"});
+            image.fitsKeywords.push_back({"DEC", "62.02302376908295", "Declination of the center of the image (deg)"});
             writer.writeImage(image);
 
             image.imageType = Image::Flat;