How can labVIEW display translucent image (PNG GIF)

[Yukee]

Hello everybody,

                          I have search every channels and research how to display translucent image with labVIEW, but the result is failed, I can display PNG and GIF image at Picture Control, and can get transparent showing, but I can't disaplay a translucent image as translucent effect. who can ?  

[tst]

You can do this in the FP by using software which knows how to save transparent images. The quick example attached was made in Photoshop, but I think GIMP can do this as well. I don't know if this can be done with picture controls as well.

[zou]

The picture control uses the old style, mask, to display transparnt images.  It can only be transparent or opaque.

In order to display translucent image, you have to use alpha change (the high 8 bit of 32 bit data).

In Window XP, you actually can define the translucent level for every pixel, but LabVIEW doesn't support that yet.

George Zou

http://gtoolbox.yeah.net

Message Edited by zou on 07-19-2006 12:32 PM

[Yukee]

Thanks all, Yes, Picture Control can't support display Translucent image effect, but labVIEW FP can do this, if we can dynamic load translucent image to FP, we can make the FP as a dummy "Picture Control", but I can't find any property node or invoke node to load the image....and so on. 

[tst]

You might be able to do that with a picture ring, which will let you have several images, but you still won't be able to dynamically change them.

Other options would be ActiveX or subpanels, but I don't know how well they would work. If you have 8, maybe you can do this with an Xcontrol?

[Yukee]

Thanks tst, and I found a method attached can show the translucent image effect, that is cool, but the process needs long time.......

[zou]

LabVIEW is not a good tool to manipulate pixels for a big image.  The double For loop slows you down.

You can use a C-dll to manipulate pixels.

George Zou

http://gtoolbox.yeah.net

[zou]

If all you want to do is using another image as "background", then the mask-technique should work for you.

All you have to do is define the current backgroud color as transparent color in the mask VI.  Unless, of course,

you current background color is not a single color, but a range of similar colors.  In this case, you still can

manipulate image to make the background color a single color.

The difference is that you can have a vivid new background.

George Zou

http://gtoolbox.yeah.net

[Yukee]

Thanks zou,

 Actually, that I need a background and a translucent front image. so the mask can't rearch my goal, mask just can process some transparent image case. maybe I have to call C Dll or the other API to get this target.