Qpixman makes gui run slow

Garza

Hi, Im displaying .png images on a qwidget using a Qpixmap and a qlabel. The thing is when I have a large number of images the application start running slow. I am plotting the values of a sensor and on this qwidget I plot the image corresponding for that sensor frame. The GUI works for small set of images but I have large set in the Terabyte size and there the GUI fails, the slow runnings starts after a few secons from starting to run the data. This is the function I use to show the pngs for every frame of the sensor this is called:
QPixmap p;
p.load(canpath_CameraTeam+framenames_frontCam[frameNum]);
ui->label->setPixmap(p);

thanks for the help

JoeCFD

create a cache with std::queue to store only some of the images and use a timer to pop them up one after another for display.
You can store their names and load them only when it is their turn for display

SGaist

@Garza said in Qpixman makes gui run slow:

The GUI works for small set of images but I have large set in the Terabyte size and there the GUI fails

Hi,

Did you consider optimizing the way you load and use your images ? Trying to put terabytes of images inside an application will make any computer trash unless you have a machine that can handle petabytes of RAM.

Garza

@SGaist Hi,

The images are stored somewhere and I just open the one with the name corresponding to the current frame.

jsulm

@Garza Did you check the memory usage of your application?

SGaist

@Garza said in Qpixman makes gui run slow:

@SGaist Hi,

The images are stored somewhere and I just open the one with the name corresponding to the current frame.

Here is likely one issue: how are you handling that one ?
Are you replacing the one from the previous frame ?
Are you opening a new one ?
How are you handling your QPixmap objects ?

Garza

@SGaist currently I'm just calling this function and not handling what you mentioned. Will have a look at it. Does image size is an issue? is 2048x1280.

Garza

@jsulm not yet, will do.

SGaist

@Garza said in Qpixman makes gui run slow:

@SGaist currently I'm just calling this function and not handling what you mentioned. Will have a look at it. Does image size is an issue? is 2048x1280.

It depends on:

At which pace do you load them ?
file compression level
storage type and speed
if network, network speed
your machine specification