Picture zoom distortion

[Thomas_ST]

Hello,

I'm using LabVIEW 7.0 and W2k.
My problem is about picture control and his zoom factor function. When
the zoom factor is too high (ie >20), the display is deformed: a pixel
is not square.
Moreover, the distortion depends on the position of the scrollbar: at
the center of the picture, a pixel has a size of 20*20 (normal!) but
at top-center, it has a size of 20*10 and of 10*20 at left-center!!!
By the fact that I need to know the position of the mouse on the
picture to display the pixel value, the pointed pixel does not
correspond to the pixel which value is displayed.

Hope someone has a solution or at least an explanation...

Best regards.

[windychris]

Hi labview folks,

this bug seems to be still present in Labview 2009, 5 years later...

For a picture control or indicator, if you apply a very large zoom factor to a picture by the propery node, the picture gets distorted.

E.g.:iIf you have a 14 megapix picture, it starts at a zoom factor of about 300%, and there are jumps in the zooming.

When this starts, depends on the picture size and zoom factor - and which part of the picture you zoom.

Is there anyone who knows a solution?

Regards

[wimba]

Hello forum users,

I am also observing this faulty bevahiour of the picture control in LabVIEW 2009. The gist of the matter:

• high zoom factors distort the image
• the value of the zoom factor at which the distortion starts depends on the resolution of the image displayed in the picture control
• the distortion is different depending on the section currently displayed in the picture control

In order to test these observations, I put a transparent picture control over a white one and loaded different images into the two (a jpeg in the white one and LabVIEW-generated drawings in the transparent one on top).

Zooming in simultaneously at different sections of the images leads to a relative displacement of the previously correctly super-imposed images. Zooming out puts the drawn elements back in the right places.

Can any NI employee confirm this behaviour? I suspect that the solution is "use the NI Vision/IMAQ software to display images", which is currently not an option due to the added price of the packet.

Thank you very much in advance and have a nice day.