WDM (Windows Driver Model) Video Control

video control

As well as the traditional image controls, you can use the Live buttons to enable and disable the live image and Capture to acquire an image.

 

overlay control

From this window you can activate and control the live image overlay.

Thebutton allows you to load an image. This image is superimposed on the live image as a transparent layer. The On/Off switch activates the level of transparency through the cursor.
The button captures an image which can be overlaid on top of the live image.

The buttons delete respectively the loaded image and the graphic part of the live image such as the measurements or the text.

The text box displays the name of the loaded image.

The multimedia buttons are activated from the moment an image is loaded by pressing the button. The Play button activates the overlay reproduction mode between the images in the folder and the live image. The interval in seconds is specified at the side.

 

video format

    1. Normal: the loaded image occupies the whole video window (default);

    2. Horizontal Split: the loaded image occupies the whole video window but only its lower half is visible and as an overlay;

    3. Vertical Split: the loaded image occupies the whole video window but only its right-hand half is visible and as an overlay;

These modes can be useful to make visual comparisons both between static images and between sequences of images through the reproduction mode.

 

Full Screen Mode

The button provides full screen viewing. The transparency of the images can be controlled with the mouse wheel. If a function of measurement is active, it will remain so.
To restore normal video mode press the <
Esc> key.

 

graticules

The switch activates the crosshair graticule. When pressed, the graticule moves on the image by moving the mouse; when released, the graticule is locked and takes on the stroke color.
The switch activates a double crosshair graticule. When pressed, the graticule moves on the image by moving the mouse. The left mouse button swaps the active graticule, whereas the right mouse button locks them temporarily. In this position the graticules can be moved with the arrow keys: by holding the <Shift> key down, the arrow keys move the other graticule. By releasing the switch the graticules are locked and take on the stroke color.
The switch is similar to the previous one but displays the distance between the two pairs of lines. If the Vickers measuring mode is active, the test values are also displayed.
The button deletes the graticules.
 

Graphic Editor
Allows you to create squared grid or circular crowns graticules specifying the pitch and the number of squares or crowns.
If the image is calibrated, by pressing the    or button, the graticule will be applied to the image.
If the Automatic Number check box is selected, the whole image will be overlaid with the chosen type of graticule.

The  buttons insert the graticules created in the Preferences pull-down list.

 

advanced

capture device

All the WDM (Windows Driver Model) devices in the system are displayed in this list. The device can be activated by selecting it with the mouse. Several devices and videocameras can therefore exist.
The program does not support more than one device with the same name as the driver.

 

input

The Pin selection is automatic for known drivers.
If the device is not in the system's database, the Pin must be specified manually. The Property buttons can provide the necessary information. If the Pin is modified, press Save to confirm.

 

output

The Pin selection is automatic for known drivers.
If the device is not in the system's database, the Pin must be specified manually. The Property buttons can provide the necessary information. If the Pin is modified, press Save to confirm.

 

source video window

The controls in the window allow you to eliminate the possible vignetting of the live image (black frame) and to adjust the scale factor to correct the image coming from a non-square pixel camera.

Scale factor calculation procedure for non-square pixel WDM devices

Once the horizontal calibration has been performed, rotate the reference scale through 90° and acquire a new image.

From the Measure menu or with the X-Vick measuring graticules, measure vertically the same distance on the reference scale. If the image was acquired with a square pixel device the vertical length will be the same as the horizontal one. If instead the two lengths differ by an unacceptable degree, you will need to recalculate the new scale factor (F).

F = (horizontal length) divided by (vertical length);

If F is greater than 1 then BOTTOM = BOTTOM divided by F;

If F is less than 1 then RIGHT = RIGHT multiplied by F;

Example

Let us suppose that the same distance is measured horizontally and vertically and that the horizontal length is 300 microns and the vertical length is 295,833 microns.

The scale factor will be 300/295,833 = 1,01408

Since it is greater than 1, the new value for BOTTOM = 576 / 1,01408, that is, BOTTOM = 568.
In this case the RIGHT value need not be modified.
Confirm by pressing Apply and restart the program.

 

destination video window

The live image window can be resized to adapt it to the work environment in view of the resolution chosen for the VGA card.
The size modification can require a new calibration of the system's optics.