This LabVIEW example copies form an image the selected pixel data into an array.

  1. Create Image Reference:

    • The “OLVCreate” function (1) initializes a new, empty image reference.
    • In LabVIEW, image data is handled by references, meaning the wire carries a pointer to the image data’s location in memory, not the image data itself.
    • This is a crucial distinction, as image references do not adhere to LabVIEW’s standard dataflow paradigm where data is copied between functions.

  2. Read Image File:

    • The “OLVReadFile” function (2) loads an image from the specified file path (CandCan 00.png).
    • When the “UseFilePartImageType” input is set to TRUE (as indicated by the constant), the appropriate image file format reader is automatically selected, simplifying the loading process.

  3. Get Last Event (Image Control):

    • The “GetLastEvent Methode” (3) retrieves information about the most recent user interaction with the “Image” control.
    • In this context, it is likely configured to trigger when a “Mouse Up” event occurs.
    • This event signifies that the user has completed drawing a region of interest (ROI) on the displayed image.

  4. Extract ROI as Array:

    • Within the “Image: Mouse Up” event structure, the “OLVImageToArray” function (4) extracts the pixel data contained within the user-defined ROI.
    • The “Pixel” output provides the image data within the ROI as an array, enabling further analysis or processing.

  5. Dispose Image:

    • Finally, the “OLVDispose” function (5) releases the memory allocated for the image data referenced by the initial “OLVCreate” function.
    • It is essential to dispose of image references when they are no longer required to prevent memory leaks and ensure efficient memory management within your LabVIEW application.

ImageToArray