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PierB

IMAQ ImageToArray issue

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Hello,

I have begun a VI to manipulate jpg : the VI takes 2 jpg, convert them to BW, scales and translates them and finally superimpose recompile them as different color channel (Red and Green) of a new image.

This does work well until the recombination step : I cannot get any output from the ImageToArray function. I tried many work around such as saving the image in another file, changing the structure of the file (event - stacked), using local variables, ... but nothing seems to work

Thank you for any help or comments,

Pierre

SLMv05.vi

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Problem solved with the merge overlay function : see thread https://forums.ni.com/t5/Machine-Vision/save-image-with-overlay-to-jpeg-file/td-p/99104

The problem lies in the principle of the overlay, which does not alter the initial image (just the Labview display). To alleviate it you basically just need to invert a merge overlay function.

Cheers,

Pierre

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You could also do all of this using just the Vision functions, without using arrays or overlays, and it's probably much easier.  Have a look at the IMAQ ReplaceColorPlane function, which allows you to place grayscale images in separate planes of a color image.  To translate the images, look at the IMAQ ImageToImage function which is used to place a small image at a specified location within a larger image.

 

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