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Custom image plugin testing difficulties

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  • S Offline
    S Offline
    SGaist
    Lifetime Qt Champion
    wrote on 2 Apr 2015, 23:58 last edited by
    #6

    Without seeing your code, it's pretty much Crystal Ball Debugging (™) I can't say

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    • C Offline
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      ChrisM87
      wrote on 3 Apr 2015, 02:21 last edited by ChrisM87 4 Mar 2015, 05:47
      #7

      Well, I had posted my code in the original post. However, my handler class was tweaked a bit after spotting some errors, so here's the updated class code:

      EDIT: I did a few tests on QImageReader that should fail with unsupported format error, but I keep getting "unknown error." I attempted to load my ".pro" qmake file to see which error it would get but still unknown error. However, I compiled qtraw from Github, dropped it into an imageformats subdirectory and it ran fine.

      #include <QDataStream>
      #include <QImage>
      #include <QIODevice>
      #include <QtGlobal>
      #include <QtMath>
      #include <QVariant>
      #include <QVector>
      #include <QImageIOHandler>
      
      class TimHandler final: public QImageIOHandler
      {
      public:
      	bool canRead() const;
      	bool read(QImage *img);
      	QVariant option(ImageOption op) const override;
      	bool supportsOption(ImageOption op) const override;
      };
      
      #define BIT16 0.121568627451
      
      bool TimHandler::canRead() const
      {
      	return device()->peek(4) == "\x10\x0\x0\x0";
      }
      
      static inline quint32 rgba5551ToArgb32(quint16 c)
      {
      	quint32 r = ((c & 0xf800) >> 11) / BIT16;
      	quint32 g = ((c & 0x7c0) >> 6) / BIT16;
      	quint32 b = ((c & 0x3e) >> 1) / BIT16;
      	quint32 a = c & 1 ? 0 : 0xff;
      	
      	return ((a << 24) | (r << 16) | (g << 8) | b);
      }
      
      bool TimHandler::read(QImage *img)
      {
      	QDataStream ds(device());
      	ds.setByteOrder(QDataStream::LittleEndian);
      	quint32 magic, flags;
      	
      	ds >> magic >> flags;
      	if (ds.status() != QDataStream::Ok || magic != 0x10)
      		return false;
      	bool hasClut = flags & 0x8 ? true : false;
      	quint8 pxlMode = flags & 0x7;
      	
      	quint8 bpp;
      	switch (pxlMode)
      	{
      		case 0: bpp = 4; break;
      		case 1: bpp = 8; break;
      		case 2: bpp = 16; break;
      		case 3: bpp = 24; break;
      		default: bpp = 4;
      	}
      	
      	QVector<QRgb> clut;
      	if (hasClut)
      	{
      		quint32 colors, npals;
      		ds.skipRawData(12);
      		ds >> colors >> npals;
      		
      		for (quint16 i = 0; i < (colors*npals); i++)
      		{
      			quint16 c;
      			ds >> c;
      			clut.append(rgba5551ToArgb32(c));
      		}
      	}
      	
      	ds.skipRawData(8);
      	quint16 w, h;
      	ds >> w >> h;
      	w = (w*16)/bpp;
      	
      	if (img) delete img;
      	img = new QImage(w, h, QImage::Format_ARGB32);
      	if (hasClut) img->setColorTable(clut);
      	
      	for (quint16 y = 0; y < h; y++)
      	{
      		for (quint16 x = 0; x < w; x++)
      		{
      			switch (bpp)
      			{
      				case 4:
      				{
      					quint8 p;
      					ds >> p;
      					img->setPixel(x++, y, p & 0xf0);
      					img->setPixel(x, y, p & 0xf);
      				}
      					break;
      				case 8:
      				{
      					quint8 p;
      					ds >> p;
      					img->setPixel(x, y, p);
      				}
      					break;
      				case 16:
      				{
      					quint16 p;
      					ds >> p;
      					img->setPixel(x, y, rgba5551ToArgb32(p));
      				}
      					break;
      			}
      		}
      	}
      	
      	return true;
      }
      
      bool TimHandler::supportsOption(ImageOption op) const
      {
      	switch (op)
      	{
      		case Size:
      			return true;
      		default:
      			return false;
      	}
      }
      
      QVariant TimHandler::option(ImageOption op) const
      {
      	switch (op)
      	{
      		case Size:
      		{
      			quint32 size;
      			quint16 w, h;
      			QDataStream ds(device());
      			ds.skipRawData(8);
      			ds >> size;
      			size -= 4; // 12 - image size - palette x - palette y
      			ds.skipRawData(size);
      			ds >> w >> h;
      			return QSize(w, h);
      		}
      		default:
      			return QVariant();
      	}
      }
      
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      • S Offline
        S Offline
        SGaist
        Lifetime Qt Champion
        wrote on 3 Apr 2015, 22:54 last edited by
        #8

        Sorry about the code part, I had a problem when I read it first and only saw the end of it.
        What about a more simple json ?

        {
            "Keys": [ "tim" ],
            "MimeTypes": [ "image/x-tim" ]
        }
        
        

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        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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        • C Offline
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          ChrisM87
          wrote on 4 Apr 2015, 07:34 last edited by ChrisM87 4 Apr 2015, 07:53
          #9

          Well, while I could try that, I don't know if that's the mime type for TIM files. A Google search doesn't help either. My examination of qtraw shows that it too lacks a mime type entry. Thus, I thought it was unnecessary.

          EDIT: tried it anyway, still nothing

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          • S Offline
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            SGaist
            Lifetime Qt Champion
            wrote on 5 Apr 2015, 20:20 last edited by
            #10

            Just thought of something… Your plugin code is correct but:

            img.load("0025.tim", "tim");

            "0025.tim" is a relative path, is that image in the same folder as your executable ? You should rather give the full path to it.

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            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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            • C Offline
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              ChrisM87
              wrote on 5 Apr 2015, 23:04 last edited by ChrisM87 4 Jun 2015, 00:59
              #11

              Same directory, yep. Though of course in a real world scenario this would be different.

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              • S Offline
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                SGaist
                Lifetime Qt Champion
                wrote on 6 Apr 2015, 22:35 last edited by
                #12

                I forgot a correction I made:

                Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QImageIOHandlerFactoryInterface" FILE "tim.json")

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                Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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                • C Offline
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                  ChrisM87
                  wrote on 8 Apr 2015, 02:36 last edited by
                  #13

                  Yeah, I changed it to that in my progress trying to fix it, but no go. I booted up QtCreator and created a new project from Qt plugin template but I see nothing unusual in comparison with my code, aside from the constructor with QObject* parameter, which I skipped in my code because I saw no point for an empty constructor/destructor.

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                  • C Offline
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                    ChrisM87
                    wrote on 11 Apr 2015, 00:45 last edited by
                    #14

                    So after a little tinkering, I got qmake to generate main.moc which I thought was needed, but I'm still having issues with the plugin not being discovered. Additionally, the RGBA5551 conversion function was incorrect, which I fixed, but that shouldn't be the make-or-break factor.

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                    • S Offline
                      S Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on 11 Apr 2015, 22:46 last edited by
                      #15

                      Not being discovered or not loaded ? Did you put your plugin in a imageformats subfolder ?

                      Interested in AI ? www.idiap.ch
                      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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                      • C Offline
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                        ChrisM87
                        wrote on 12 Apr 2015, 00:03 last edited by ChrisM87 4 Dec 2015, 01:25
                        #16

                        Yep. Even set target.path in my .pro file thinking that was the issue. Qt seems very nitpicky.

                        EDIT: Just debugged again, found this gem of an error:

                        QLibraryPrivate::loadPlugin failed on "/home/admin/Documents/Qt-extra/imageformats/qtim/timtest/imageformats/libqtim.so" : "Cannot load library /home/admin/Documents/Qt-extra/imageformats/qtim/timtest/imageformats/libqtim.so: (/home/admin/Documents/Qt-extra/imageformats/qtim/timtest/imageformats/libqtim.so: undefined symbol: _ZN11QTimHandler9setOptionEN15QImageIOHandler11ImageOptionERK8QVariant)"
                        
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                        • S Offline
                          S Offline
                          SGaist
                          Lifetime Qt Champion
                          wrote on 12 Apr 2015, 23:06 last edited by
                          #17

                          Which version of Qt are you using ?
                          What happens if you try to load it by hand using QLibrary ?

                          Interested in AI ? www.idiap.ch
                          Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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                          15/17

                          11 Apr 2015, 22:46

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