VI IMAQ Create: wenn ich die Bordergröße ungleich 0 eingebe, ist Bild verzerrt

[BeatricePötschick]

Hello everybody, I not really understand why I need to use the SubVI IMAQ GetImagePixelPtr VI?

[GuenterMueller]

The VI that acquires an image from your camera just allows to copy the pixel data of an image. If you want to have the pixel values in an IMAQ image, the recommended way to do it is by using IMAQ GetImagePixelPtr. Your code looks very close to the example implementation given here.

[BeatricePötschick]

Add Andrei, where I can find the Dll Labview Move Block?

[GuenterMueller]

Look here.  There's also a VI snippet in it that you can use: Just drag the PNG on a block diagram.

[BeatricePötschick]

Hello Günther, the example which you send me, there is a "Knoten zum Aufruf externer Bibliotheken" Copy C image to labview image -> where I can find this?

[BeatricePötschick]

thank you. I will try this.

[GuenterMueller]

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@BeatricePötschick wrote:

Hello Günther, the example which you send me, there is a "Knoten zum Aufruf externer Bibliotheken" Copy C image to labview image -> where I can find this?

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Hello Beatrice.  Open a block diagram.  Press <Ctrl-Space> which will open "Quick Drop".  Start typing "Knoten ..." and hope that the node appears in your german instance of LabVIEW. As soon as it appears press Enter to select it.  Place it somewhere on the block diagram.

[BeatricePötschick]

Hello Andrey, I tried it like you. But now I don´t see a picture. But maybe the problem could be, that the size of the x-axis and the y-axis is different?

[altenbach]

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@BeatricePötschick wrote:

Hello altenbach, the loop rate is the number of the captured pictures minus 1.

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That answer does not make any sense. What are the units? A rate is typically given in  Hz. (e.g. "pictures per second" or similar).

[GuenterMueller]

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@BeatricePötschick wrote:

Hello Andrey, I tried it like you. But now I don´t see a picture. But maybe the problem could be, that the size of the x-axis and the y-axis is different?

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Hello Beatrice.

Your code has at least two issues:

(1) You must specify "Map Pixel Pointer" when calling "IMAQ GetImagePixelPtr" before running the Call Library Function Node that calls "LabVIEW:MoveBlock".    To my opinion Andrey forgot an "Unmap Pixel Pointer" after the "MoveBlock" (but I didn't check this for memory consumption issues).

(2) MoveBlock takes three parameters in the order source, dest, size. You have wired the pixel pointer as parameter#1 and the image array as parameter#2.    Your image array must be wired as parameter#1 and the pixel pointer as parameter#2.
 How could this work without a crash in LabVIEW?