added option to use palette from file

README.md

@@ -12,5 +12,8 @@ make -j4
 ### Example scanning the FM radio band
 `soapy_power -f 80M:110M -n 10 -e 30 -B 30k -k 30 --pow2 -F rtl_power -R | ./Livepow`
 
-### Example loadind the data in the file scan.csv
+### Example loading the data in the file scan.csv
 `./Livepow scan.csv`
+
+### Example reading from scan.csv using the palette from palette.png while skipping the first 22 lines
+`./LivePow -p palette.png -s 22 scan.csv`

displayarea.cpp

@@ -46,17 +46,27 @@ bool DisplayArea::saveImage(const QString &fileName, const char *fileFormat)
     return image.save(fileName, fileFormat);
 }
 
-void DisplayArea::updateColorMap(float oldMin, float oldMax, float newMin, float newMax)
+void DisplayArea::updateColorMap(float oldMin, float oldMax, float newMin, float newMax,QImage palette)
 {
     QRgb* imagePixels=(QRgb*)image.bits();
+    QRgb* palettePixels=(QRgb*)palette.bits();
+    unsigned long size=palette.sizeInBytes()/sizeof(QRgb);
     for(unsigned long long i=0;i<image.sizeInBytes()/sizeof(QRgb);i++){
         QRgb currentColor=imagePixels[i];
-        QRgb newColor=qRgba(remap(qRed(currentColor),oldMin,oldMax,newMin,newMax),remap(qGreen(currentColor),oldMin,oldMax,newMin,newMax),remap(qBlue(currentColor),oldMin,oldMax,newMin,newMax),qAlpha(currentColor));
+        if(qAlpha(currentColor)==0) continue;
+        unsigned long oldIndex=findPaletteIndex(currentColor,palettePixels,size);
+        QRgb newColor=palettePixels[remap(oldIndex,oldMin,oldMax,newMin,newMax)];
         imagePixels[i]=newColor;
     }
 }
 
-char DisplayArea::remap(char c, float omin, float omax, float nmin, float nmax)
+unsigned long DisplayArea::findPaletteIndex(QRgb col, QRgb* palette,unsigned long size)
+{
+    for(unsigned long i=0;i<size;i++) if(col==palette[i]) return i;
+    return 0;
+}
+
+unsigned long DisplayArea::remap(unsigned long c, float omin, float omax, float nmin, float nmax)
 {
     float nVal=(255*(omin-nmin)+c*(omax-omin))/(nmax-nmin);
     return qRound(nVal);

displayarea.h

@@ -10,7 +10,7 @@ public:
     DisplayArea(QWidget *parent = nullptr);
     void setPixel(int x,int y,unsigned int col);
     bool saveImage(const QString &fileName, const char *fileFormat);
-    void updateColorMap(float oldMin,float oldMax,float newMin,float newMax);
+    void updateColorMap(float oldMin,float oldMax,float newMin,float newMax,QImage palette);
 
 protected:
     void paintEvent(QPaintEvent *event) override;
@@ -18,7 +18,8 @@ protected:
 private:
     void resizeImage(QImage *image, const QSize &newSize);
 
-    char remap(char val,float omin,float omax,float nmin,float nmax);
+    unsigned long remap(unsigned long val,float omin,float omax,float nmin,float nmax);
+    unsigned long findPaletteIndex(QRgb col,QRgb* palette,unsigned long size);
 
     QImage image;
 

inputparser.cpp

@@ -17,9 +17,18 @@ InputParser::InputParser(FILE* input,DisplayArea* display)
     timer->start(0);*/
 }
 
-void InputParser::sendParameters(unsigned long ignoreFirstNLines)
+void InputParser::sendParameters(unsigned long ignoreFirstNLines,QString palettePath)
 {
     this->ignoreFirstNLines=ignoreFirstNLines;
+    if(palettePath!=NULL){
+        usePalette=true;
+        palette=QImage(palettePath);
+    }
+    else{
+        palette=QImage(255,1,QImage::Format_ARGB32);
+        QRgb* palettePixels=(QRgb*)palette.bits();
+        for(unsigned int i=0;i<palette.sizeInBytes()/sizeof(QRgb);i++) palettePixels[i]=qRgb(i,i,i);
+    }
 }
 
 void InputParser::process()
@@ -141,14 +150,18 @@ void InputParser::sendPixel()
         float newMin=qMin(currentPowerValue,minPow);
         float newMax=qMax(currentPowerValue,maxPow);
 
-        display->updateColorMap(minPow,maxPow,newMin,newMax);
+        display->updateColorMap(minPow,maxPow,newMin,newMax,palette);
 
         minPow=newMin;
         maxPow=newMax;
     }
 
-    int col=qRound((currentPowerValue-minPow)*255/(maxPow-minPow));
-    display->setPixel(currentX,currentY,qRgba(col,col,col,255));
+    QRgb color;
+    double normCol=(currentPowerValue-minPow)/(maxPow-minPow);
+    QRgb* palettePixels=(QRgb*)palette.bits();
+    color=palettePixels[qRound(palette.sizeInBytes()/sizeof(QRgb)*normCol)];
+
+    display->setPixel(currentX,currentY,color);
     currentX++;
     currentPowerValue=0;
     decimalIndex=1;

inputparser.h

@@ -6,6 +6,7 @@
 #include <QObject>
 #include <QRandomGenerator>
 #include <QDateTime>
+#include <QImage>
 
 class DisplayArea;
 
@@ -24,7 +25,7 @@ class InputParser : public QObject
 public:
     InputParser(FILE* input,DisplayArea* display);
 
-    void sendParameters(unsigned long ignoreFirstNLines);
+    void sendParameters(unsigned long ignoreFirstNLines,QString palettePath);
 
 private:
     unsigned long minFreq=-1;
@@ -40,6 +41,9 @@ private:
     unsigned long nbOfLinesParsed=0;
     unsigned long ignoreFirstNLines=0;
 
+    bool usePalette=false;
+    QImage palette;
+
     line currentLine;
 
     FILE* input;

main.cpp

@@ -12,11 +12,16 @@ int main(int argc, char *argv[])
     argsParser.addHelpOption();
     argsParser.addPositionalArgument("source","csv file to read data from, default stdin");
 
-    QCommandLineOption skipFirstLines(QStringList() << "s" << "ignoreFirstLines",
+    QCommandLineOption skipFirstLines(QStringList() << "s" << "skipFirstLines",
               "Skip the first <n> lines",
               "number of lines");
     argsParser.addOption(skipFirstLines);
 
+    QCommandLineOption palette(QStringList() << "p" << "palette",
+              "Use the palette specified in the file",
+              "Path to the file");
+    argsParser.addOption(palette);
+
     argsParser.process(a);
 
     MainWindow w;

mainwindow.cpp

@@ -41,10 +41,17 @@ void MainWindow::sendArgs(QCommandLineParser *argsParser)
 
     parser=new InputParser(input,displayArea);
 
+    unsigned long nbOfLinesToSkip=0;
     if(argsParser->isSet("s")){
-        parser->sendParameters(argsParser->value("s").toLong());
+        nbOfLinesToSkip=argsParser->value("s").toLong();
     }
 
+    QString palettePath=NULL;
+    if(argsParser->isSet("p")){
+        palettePath=argsParser->value("p");
+    }
+    parser->sendParameters(nbOfLinesToSkip,palettePath);
+
     QThread* workerThread=new QThread();
 
     parser->moveToThread(workerThread);