Live EDF

Image-Pro with Capture Module Only

Live EDF (Extended Depth of Field) allows you to create real-time EDF images using a microscope with a manual focus control. It also supports stereo microscopes, where changing the focus position shifts the image.

To use Live EDF, go to the Capture tab on the Image-Pro ribbon. You will see the Live EDF group.

The Start button will be enabled when a live preview is active. Clicking the button will start the EDF acquisition on the live image. When the live EDF process is active the button background turns orange and the text changes to Stop. Clicking the button again will stop live EDF.

Note: The Live EDF option can also be used on a sequence file.  In this case, when you click the Start button, Image-Pro automatically creates an EDF composite image out of the sequence file frames based on the current Live EDF options settings (discussed below).  

When the Accumulate option is on every frame of the live image stream is added to the composition. As you adjust the focus on the microscope, the best-focus data is automatically detected and added to the Live EDF preview.  This option is preferable when "Local contrast" is selected for Composition (described below). In other composition modes you can switch this option off and add images to a composite manually by clicking the Add button.

Clicking the drop-down arrow of the Live EDF tool displays a submenu of additional options, including the following.

Start: Click this option to start the Live EDF acquisition.

Auto Align (Stereo): Check this option to enable auto align for every acquired frame. Use this option on stereo microscopes where changing the focus position shifts the image.

Composition: Select from this pull-down list box the desired composition mode:

  • Local contrast: Choose this option for real time EDF using the Local Contrast algorithm.  This is most useful for high contrast brightfield images.
  • Maximum: Choose this option for real-time EDF using the maximum composition mode for  sample imaging on a dark background. For example, imaging of fluorescent samples.
  • Minimum: Choose the minimum composition mode for transparent mode illumination of  brightfield images
  • Difference: Illustrates the difference between the base image and the current image (image with a grey background)
  • Abs Difference: Shows the absolute difference between the base image and the current image. Background is black, but you can also activate Pseudo-color on gray images, so you that can see changing objects in color on a black background.

Options: Click this button to open the "'Live EDF" page of the Image-Pro Options dialog. The "Live EDF" page allows you to set the following options.

  • Alignment area width/height: Indicate width and height of the size of the area in the middle of the image, which is used for stereo alignment of images in EDF. If the images have alittle texture the area can be extended to achieve better correlation
  • Align by Previous: This option defines the alignment method, which is used with Auto Align (Stereo) mode. When the option is on, the new image is aligned by the last added to image, then the option is off, the start image is used to align all following images.
  • Defocusing diameter: Defines the size of the filter that detects in-focus areas on the image. The default value is 6.
  • Plane blending: Sets the size of the blending area between in-focus zones from different planes. The default value is 4.
  • Side by side: Determines the placement of the Live EDF window in the application workspace.  Select "Side by side" to split the workspace into 2 panes, where the live preview window is on the left and the output window is on the right.  
  • Run in background:  When the option is on, the Live EDF is started in a separate thread. This option should be used with multi-core processors, so Live EDF will run in parallel to the live preview and not slow down preview frame rate.
  • Reset to Default: Click this button to reset the Live EDF settings to the default selections.