Jpeg Image not getting displayed

nitks.abhinav

Hi,

I am having issues in displaying jpeg image, My code first displays the gif image using QMovie.

The finished signal of movie is connected to slot which should show a jpeg image.

Below is the sample code, Base is the main GUI thread.

Note: If I use fbi tool to display image it works fine.

void Base::displayWelcomeScreen()
{
    //Start the  presentation (gif)    
    presnLabel.resize(480,350);   //keeping width 350 acc to the gif
    movie.setFileName("/usr/.images/is5RaptorLoading.gif");
    presnLabel.setMovie (&movie);
    movie.start ();
    presnLabel.show();
}
/*Slot function*/
void Base::displaySysInfoScreen()
{
    //Display the Raptor system information screen
    presnLabel.hide();
    qDebug() << "Main Thread (BASE): Displaying the  system information screen \n";
    //system ("fbi -T 1  /usr/.images/is5RaptorSysInfo.bmp -d /dev/fb0  -noverbose");
    //sleep(5) ;
    //system("killall fbi");

    QPixmap pm("usr/.images/is5RaptorSysInfo.jpeg");
     presnLabel.setPixmap(pm);
     presnLabel.show();
    sleep(5) ;
    presnLabel.hide();
}

mrjj

Hi
Using sleep is a bad idea.
It will halt the event loop and might prevent the window from
showing/painting. Not sure its that but easy to test.

void Base::displaySysInfoScreen()
{
QPixmap pm("usr/.images/is5RaptorSysInfo.jpeg");
presnLabel.setPixmap(pm);
presnLabel.show();
// sleep(5) ;
// presnLabel.hide();
}

and then call void Base::displaySysInfoScreen() directly.

Does image show ?

SGaist

Hi,

Your sleep call blocks the event loop thus your label never gets shown. Use a single shot QTimer if you want to hide your widget after a given delay.

nitks.abhinav

I have removed the sleep but still not able to see image, below is the changed code.
Also changed the slot function to "rcvPresntationFinisedNotif" which is calling displaySysInfoScreen().

void Base::displaySysInfoScreen()
{
    //Display the Raptor system information screen
    QPixmap pm("usr/.images/is5RaptorSysInfo.jpeg");
     presnLabel.setPixmap(pm);
     presnLabel.show();
    //sleep(5) ;
    //presnLabel.hide();
}
/SLOT fn */
void Base::rcvPresntationFinisedNotif()
{
    qDebug()<< "Main Thread (BASE): Received raptor boot presentation finished signal from base thread\n";
    displaySysInfoScreen();
    //displayLsrScreen();

    qDebug()<< "Main Thread (BASE): Now starting worker threads , connecting to notif server and watchdog msg queue\n";
    drpThread->start();
    clientThread->start();

    //Connect to the server
    clientThread->serverConnect();

    //Connect to the message queue in watchdog
    clientThread->watchdogConnect();
}

SGaist

You are using a relative path so unless the folder is located in the same folder as the application, the file won't be found.

jsulm

@nitks.abhinav said in Jpeg Image not getting displayed:

QPixmap pm("usr/.images/is5RaptorSysInfo.jpeg");

Looks like you forgot / before usr.
Also: this path is quite unusual, I never saw anybody creating a hidden directory in /usr, why are you doing this? It is against UNIX/Linux file system structure. If you want to put some data globally for your application do it in /usr/share/YOUR_APP_NAME

nitks.abhinav

Couple of issues were there , path with missing / and also jpeg plugin was not there, Thank you.

I have couple of more questions related to this:

Can bmp image be displayed in similar way?
Image is not aligned to the LCD screen, I can see it shifted to both right and up. How to align it?

Thanks

mrjj

hi
1:yes
http://doc.qt.io/qt-5/qtimageformats-index.html
2: not sure what u see but the label can center it
there is a property

nitks.abhinav

I have used presnLabel.showMaximized(); and it seems to be working fine. Assume it is correct way.

mrjj

yes when you use the label as window it should be fine.

nitks.abhinav

Thankyou for all the help!

mrjj

@nitks.abhinav
Np, happy programming and remember to set as solved