There is one segment when play gif with movie

jmdvirus

Any body has this problem?
code is below, I just want play gif cycle

m_app = new QApplication(argc, args);
QWidget w;
    w.show();
QLabel label(w);
    QMovie movie(file);
    label.setMovie(&movie);
    movie.start();
    label.show();
    time_t t = time(NULL);
    int c = 0;
    printf("movie cycle show\n");
    while (true) {
        m_app->eventDispatcher();
        m_app->processEvents();
        if (time(NULL) - t > 30000) {
            break;
        }
        if (c++ % 100000 == 0) {
            c = 1;
        }
        if (movie.state() == QMovie::NotRunning) {
//            printf("movie status changed to rerun\n");
            movie.start();
        }
    }

and gdb give this:

(gdb) bt full
#0  0x414c7044 in __memcpy_neon () from /lib/libc.so.6
No symbol table info available.
#1  0x409371f8 in QImage::copy (this=0xc8b84, r=...) at image/qimage.cpp:1154
        ss = 0x41fd5008 '\377' <repeats 200 times>...
        dd = 0x41dd1008 '\377' <repeats 200 times>...
        image = {<QPaintDevice> = {
            _vptr.QPaintDevice = 0x40d8520c <vtable for QImage+8>, 
            painters = 0, reserved = 0x0}, d = 0xfda98}
        x = -1090522388
        y = 820584
        w = 808376
        h = 1
        dx = 0
        dy = 0
        image = warning: can't find linker symbol for virtual table for `QImage' value
warning:   found `QImageIOHandler::device() const' instead
{<QPaintDevice> = {
            _vptr.QPaintDevice = 0x40955c10 <QImageIOHandler::device() const+24>, painters = 56356, reserved = 0xc8b18}, d = 0xbefff27c}
        pixels_to_copy = -1090522372
        lines_to_copy = 820584
        byteAligned = false
#2  0x40936f4c in QImage::detach (this=0xc8b84) at image/qimage.cpp:1079
No locals.
#3  0x4097d378 in QRasterPlatformPixmap::createPixmapForImage (this=0xc8b58, 
---Type <return> to continue, or q <return> to quit---
    sourceImage=..., flags=..., inPlace=false) at image/qpixmap_raster.cpp:341
        format = QImage::Format_RGB32
#4  0x4097c5f4 in QRasterPlatformPixmap::fromImage (this=0xc8b58, 
    sourceImage=..., flags=...) at image/qpixmap_raster.cpp:146
        image = {<QPaintDevice> = {
            _vptr.QPaintDevice = 0x40d8520c <vtable for QImage+8>, 
            painters = 0, reserved = 0x0}, d = 0xc8568}
#5  0x40971514 in QPixmap::fromImage (image=..., flags=...)
    at image/qpixmap.cpp:1606
        data = {d = 0xc8b58}
#6  0x40978634 in QMoviePrivate::infoForFrame (this=0xc8238, frameNumber=131)
    at image/qmovie.cpp:379
        anImage = {<QPaintDevice> = {
            _vptr.QPaintDevice = 0x40d8520c <vtable for QImage+8>, 
            painters = 0, reserved = 0x0}, d = 0xc8568}
        aPixmap = {<QPaintDevice> = {_vptr.QPaintDevice = 0xbefff46c, 
            painters = 1, reserved = 0xb39c1bc5}, data = {d = 0x41570000}}
        aDelay = 0
#7  0x409788f0 in QMoviePrivate::next (this=0xc8238) at image/qmovie.cpp:439
        time = {mds = 18152389}
        info = {pixmap = {<QPaintDevice> = {_vptr.QPaintDevice = 0x88378, 
              painters = 63488, reserved = 0x88378}, data = {d = 0x0}}, 
          delay = 0, endMark = 48}
---Type <return> to continue, or q <return> to quit---
        scaledSize = {wd = 0, ht = 1}
        processingTime = 566572
#8  0x40978c04 in QMoviePrivate::_q_loadNextFrame (this=0xc8238, 
    starting=false) at image/qmovie.cpp:490
        q = 0xbefffa68
#9  0x40978bcc in QMoviePrivate::_q_loadNextFrame (this=0xc8238)
    at image/qmovie.cpp:484
No locals.
#10 0x40979f14 in QMovie::qt_static_metacall (_o=0xbefffa68, 
    _c=QMetaObject::InvokeMetaMethod, _id=12, _a=0xbefff6a8)
    at .moc/moc_qmovie.cpp:164
        _t = 0xbefffa68
#11 0x4102b9b8 in QMetaObject::activate(QObject*, int, int, void**) ()
   from /usr/local/qt5-arm/lib/libQt5Core.so.5
No symbol table info available.
#12 0x41038808 in QTimer::timerEvent(QTimerEvent*) ()
   from /usr/local/qt5-arm/lib/libQt5Core.so.5
No symbol table info available.
#13 0x4102c708 in QObject::event(QEvent*) ()
   from /usr/local/qt5-arm/lib/libQt5Core.so.5
No symbol table info available.
#14 0x4012a37c in QApplicationPrivate::notify_helper(QObject*, QEvent*) ()
   from /usr/local/qt5-arm/lib/libQt5Widgets.so.5

Can anybody give some advice? It's in armv7, and linux-4.9
And it will run for some seconds, less then one minute, and then give segment fault.

SGaist

Hi and welcome to devnet,

Why not just start the event loop like for any Qt GUI application ?

jmdvirus

Sorry, what event loop do you mean? And how to write?

KroMignon

@jmdvirus said in There is one segment when play gif with movie:

And how to write?

Your application is not really "Qt conform", you can try this way:

m_app = new QApplication(argc, args);
QWidget w;
    w.show();
QLabel label(w);
    QMovie movie(file);
    
    // to restart the movie
    QObject::connect(&movie, &QMovie::finished, m_app, [=]()
    {
        printf("rerun movie\n");
        movie.start();
    }
    );
    label.setMovie(&movie);
    movie.start();
    label.show();
    printf("movie cycle show\n");

    // start the event queue processing...
    m_app->exec();

I would also suggest you to read at least those articles:

SGaist

To add to @KroMignon, m_app should be on the stack, there's no need to allocate it on the heap.

jmdvirus

Oh, yes, thank you. But I just use another way to do it

class MovieTest : public QWidget {
        Q_OBJECT
    public:
        explicit MovieTest(QWidget *parent = NULL) {
            this->setParent(parent);
            connect(&m_movie, SIGNAL(finished()), this, SLOT(restartMovie()));
        }

        int init(const char *file) {
            m_movie.setFileName(file);
            return 0;
        }

        int start() {
            m_label.setMovie(&m_movie);
            m_movie.start();
            return 0;
        }

    public slots:
                void restartMovie() {
            printf("move status: [%d]\n", m_movie.state());
            m_movie.start();
        };

    protected:
        bool event(QEvent *event) override {
            printf("--------- get event ???[%d]\n", event->type());
            printf("move status [%d]\n", m_movie.state());
        }

    private:
        QMovie   m_movie;
        QLabel   m_label;
};

But the segment also exist

KroMignon

@jmdvirus First, always call base class constructor in you constructor, and prefere new connect syntax to detect possible typo errors on build time:

explicit MovieTest(QWidget *parent = NULL): QWidget(parent)
       {
            connect(&m_movie, &QMovie::finished, this, &MovieTest::restartMovie);
        }

Second, how to do you have changed the main() function?

jmdvirus

I move connect to init function, and then change main to below

QApplication app(argc, args);

  printf("Start to show\n");
  MovieTest m;
  m.init(args[1]);
  m.start();
  m.show();

  app.exec();

but problem is also exist, any other need change?

KroMignon

@jmdvirus Do you have change the constructor?

Because I am lazy, I made a little google search and found this => https://doc.qt.io/qt-5/qtwidgets-widgets-movie-example.html

I think this is a good starting point for you and will help you to understand what you are doing wrong.

jmdvirus

No, show is normal, it will segment fault after show some times
This may help to know

# test_qt_tips bootLoading.gif 
Start program
Start to show
move status: [0]
move status: [0]
Segmentation fault

"move status" means restart show movie, but it will segment fault after how many times is unsure, maybe more, or less.

construct like this

explicit MovieTest(QWidget *parent = NULL) {
            this->setParent(parent);
            m_label.setParent(this);
        }

        int init(const char *file) {
            m_movie.setFileName(file);
            connect(&m_movie, SIGNAL(finished()), this, SLOT(restartMovie()));
            return 0;
        }

KroMignon

@jmdvirus Because I am a lazy developer, I made a little Google search and found this ==> https://doc.qt.io/qt-5/qtwidgets-widgets-movie-example.html.

I think this is a good starting point for you application and I will help your to understand what you may have do wrong.

jmdvirus

ok, thank you!