Priority: Not Evaluated
Affects Version/s: 1.1.2
Fix Version/s: None
N8, Qt 4.7.3, Mobility 1.1.2, Performance Monitoring Tool (the one provided along with SDK).
We are trying to use QML camera element in one of our application. The camera element is dynamically created and destroyed when no more required.
Our application involves variety of animations like screen swipe in/out, screen flipping, animated popup dialogs etc.
We noticed that all these animations become noticeably slow once the camera is created and even after it is destroyed.
We further analyzed the problem to figure out the problem area. For this we used the performance monitoring tool provided with Qt SDK.
PFA a test QML app (Test_App_QMLCamera.zip) used to reproduce the issue.
Test Environment: N8, Qt 4.7.3 and Mobility 1.1.2
1. Launch the performance monitoring tool and push it in background, keep watch on the CPU utilization.
2. Launch the test application (it contains infinite animation of bouncing balls) , check the CPU utilization with animation (it will be in range 24-25%)
3. Launch and dismiss popup dialog, notice the animation performance, check the CPU utilization (will be in range 24-25%)
4. Launch the camera and check the CPU utilization (it hits around 100%)
5. Launch popup dialog and notice the degradation in animation performance (CPU utilization is hitting around 100% mark continuously)
6. Close the camera and check the CPU utilization, it continues to be above 95% mark.
7. Launch popup dialog and notice the degradation of animation performance even after the camera is closed.
Apparently the camera resources are not released properly even after the camera is destroyed.
To verify this behavior we even tried creating the camera using QCamera class and added it to the declarative view from back-end, however result was the same.
PFA 'Test_App_QCamera.zip' sample app using QCamera.