You construct your QImage from a uchar* right? This constructor does not take a
deep copy of the image data you pass in, it just stores it. That means that if
you for some reason delete the source data before Qt takes it into use (which
happens typically on the next paint cycle or in your custom
Thank you Allan and Gunnar,
I have tried the some of your method but no luck. When I used
Qt::NoFormatConversion flag. If I do not enable the openGL for my graphic
view, It does not draw a image and it just crash. but whenever I enable the
openGL, it draw but speed is same, in addition to that so
> On 19 Oct 2015, at 13:00, Gunnar Sletta wrote:
>
>
>> On 17 Oct 2015, at 17:28, Celal SAVUR wrote:
>>
>> Hello everyone,
>>
>> I have some performance issue when I am using QPixmap.
>>
>> I am getting image from buffer and I create QImage. After that using
>> QPixmap::fromImage(), creati
> On 17 Oct 2015, at 17:28, Celal SAVUR wrote:
>
> Hello everyone,
>
> I have some performance issue when I am using QPixmap.
>
> I am getting image from buffer and I create QImage. After that using
> QPixmap::fromImage(), creating pixmap and set it to QGraphicPixmapItem to be
> drawn in sc
Hi Oliver,
The system is linux OS. The original data is just vector of unsigned char
data, width and height and format. but format is not part of data it part
of struct. Therefore, I cannot use QPixmap.fromRawData();
I do not have any experience with openGL, If you can explain little bit ?
On Saturday 17 October 2015, Celal SAVUR wrote:
> Hello everyone,
>
> I have some performance issue when I am using QPixmap.
>
> I am getting image from buffer and I create QImage. After that using
> QPixmap::fromImage(), creating pixmap and set it to QGraphicPixmapItem to
> be drawn in scene.
>
> ...
>
> When I put the timer to see how much time Qt spending to create QPixmap, I
> realize that I converting from Qimage to QPixmap taking ~20 times more time
> than crating Qimage from buffer.
Yes, I guess that's perfectly possible. That depends off course on the original
data layout a
Hello everyone,
I have some performance issue when I am using QPixmap.
I am getting image from buffer and I create QImage. After that using
QPixmap::fromImage(), creating pixmap and set it to QGraphicPixmapItem to
be drawn in scene.
When I put the timer to see how much time Qt spending to creat