9  Working with images

The system can be set up to automatically save an image when an elevated skin temperature is detected. The operator can also save images manually. It is possible to edit saved images using the image editor.

9.1  Saving images automatically

To automatically save an image when an elevated skin temperature is detected, go to the Face detection tab on the Settings page and select the Log alarms to output folder check box. By default, this check box is cleared and no images are saved automatically.

9.2  Saving an image manually

To save an image manually, click the Save snapshot button on the toolbar or in the Camera capture pane on the Live page.

9.3  Editing images

You open the image editor by double-clicking a thermal image on the Library page.

9.3.1  Measurement tool

    You can add one or more measurement tools to the image:
  • spotmeter
  • line
  • rectangle
  • ellipse
Each measurement tool has its own settings, which are shown in the Measurements section of the properties pane.

9.3.1.1  Add a measurement tool

  1. In the image editor, click Add measurement, and then click the preferred tool.
  2. Move the tool pointer over the image and into position.
    Note that the pointer shows the temperature as it is moved around the image.
  3. Click to place the tool in the image. Click to place the start point, drag the pointer to the desired size, and then click to place the end point.
  4. Click the measurement tool.
    The properties for the tool are shown in the Measurements section of the properties pane.

9.3.1.2  Edit a measurement tool

    To move the measurement tool, follow this procedure:
  1. In the image editor, move the pointer to the center of the measurement tool.
  2. Click and hold the measurement tool, and then move it into position.
    To change size of the measurement tool, follow this procedure:
  1. In the image editor, move the pointer to the outline of the measurement tool.
  2. Click and hold the outline, and move it to the desired size and shape.

9.3.1.3  Change the settings of a measurement tool

  1. In the image editor, move the pointer to the center of the measurement tool.
  2. Right-click the tool.
    A dialog box appears with the current settings of the tool.
  3. Change the settings by selecting and deselecting the available check boxes.
    Any changes are immediately presented in the Measurements section of the properties pane.
  4. To close the settings dialog box, click anywhere on the screen.

9.3.1.4  Delete a measurement tool

  1. In the image editor, move the pointer to the measurement tool.
  2. Right-click the tool, and then click Remove.

9.3.1.5  Export to a csv file

Use the Export to csv functionality to export detailed temperature information. The export will include the temperature values of every pixel within the selected measurement tool.
  1. In the image editor, right-click the measurement tool.
    A dialog box appears with the current settings of the tool.
  2. Click Export to csv.
  3. In the Save as dialog, browse to the folder where you want to store the exported file, and then click Save.

9.3.1.6  Use coverage

Use the Coverage functionality to see, as a percentage, the number of pixels in the image that are above or below a certain temperature.
  1. In the image editor, right-click the measurement tool.
    A dialog box appears with the current settings of the tool.
  2. Click the Use coverage check box.
    Use the Above and Below boxes to change the temperature. Any changes are immediately presented in the Measurements section of the properties pane.
  3. To close the settings dialog box, click anywhere on the screen.

9.3.2  Palette

You can change the palette that is used to display the temperatures within an image. A different palette can make it easier to analyze the image.
The FLIR Screen-EST application comes with a set of predefined palettes, but custom palettes can also be used.

9.3.2.1  Change the palette

  1. In the image editor, click Select palette.
  2. Select one of the predefined palettes, or click From file to select a custom palette.

9.3.2.2  Export the palette

  1. In the image editor, click Select palette.
  2. Click Export palette.
  3. In the Save as dialog, browse to the folder where you want to store the exported palette, and then click Save.

9.3.3  Isotherms control

Use the isotherm tool to apply a contrasting color to all pixels with a temperature Above or Below a certain temperature, or within a certain temperature Interval.
Using isotherms is a good method to easily discover anomalies in a thermal image.

9.3.3.1  Add isotherm

  1. In the image editor, click Isotherms control.
  2. Select one of the following options:
    • Above
    • Interval
    • Below
  3. Select a color that will be applied to the areas that meet the temperature settings.
  4. In the Isotherms section of the properties pane, either set the temperature Limit for the Above and Below options, or set the High and Low temperatures for the Interval option.

9.3.4  Color distribution

Use the Color distribution option to change the distribution of colors in the image. A different color distribution can make it easier to analyze the image more thoroughly. The following distributions are available:
  • Histogram equalization
    The color information is distributed over the existing temperatures of the image. This method of distributing the information is especially successful when the image contains few peaks at very high temperature values.
  • Signal linear
    The color information in the image is distributed linearly with respect to the signal values of the pixels.
  • Temperature linear
    The color information in the image is distributed linearly with respect to the temperature values of the pixels.
  • Digital Detail Enhancement (DDE)
    The high-frequency content in the image, such as edges and corners, are enhanced to increase the visibility of details.

9.3.4.1  Change color distribution

  1. In the image editor, click Color distribution.
  2. Click one of the available color distributions.

9.3.5  Auto-adjust control

When you auto-adjust a thermal image, you adjust it for the best image brightness and contrast. This means that the color information is distributed over the existing temperatures of the image.
In some situations the image may contain very hot or very cold areas outside your area of interest. In such cases you might want to exclude those areas and use the color information only for the temperatures in your area of interest. You can do so by defining an auto-adjust region. Note that the defined regions will not be saved in the image.

9.3.5.1  Auto-adjust an image

  1. In the image editor, click Auto-adjust control.
  2. Select the Enable scale auto-adjust check box.

9.3.5.2  Define an auto-adjust region

  1. In the image editor, click Auto-adjust control.
  2. Select the Enable scale auto-adjust using defined rectangle check box.
    A dotted rectangle is added to the image.
  3. Move and change the size of the rectangle to suit your area of interest.
    Note how the image changes as you make your changes.
  4. To exit, click one of the icons in the bottom right corner of the rectangle:
    • To confirm the change, click the check mark.
    • To cancel the change, click the cross.

9.3.6  Crop an image

Use the Crop image option to trim the image.

9.3.6.1  Crop an image

  1. In the image editor, click Crop image.
  2. Select the Show crop rectangle check box.
    A dotted rectangle is added to the center of the image.
  3. Move the pointer to the outline of the rectangle—either one of the sides or one of the corners.
  4. Click and hold the outline, and then change the shape of the rectangle to the desired size.
  5. To exit, click one of the icons in the bottom right corner of the rectangle:
    • To confirm the change, click the check mark.
    • To cancel the change, click the cross.

9.3.6.2  Revert to the uncropped image

  1. In the image editor, click Crop image.
  2. Click Reset image.

9.3.7  Image rotation

Use the Image rotation option to rotate the image.

9.3.7.1  Rotate an image

  1. In the image editor, click Image rotation.
  2. Move the Image rotation slider to rotate the image to the desired angle, or click one of the available predefined angles.
    As an alternative, type the desired angle in the Angle text box.

9.3.8  Zoom

Use the mouse scroll button to zoom in or out the selected image.

9.3.9  Show a profile plot

The plot shows the temperature profile along a drawn measurement line in the image.
  1. In the image editor, click Show profile plot.
    An empty plot is added under the image.
  2. In the image editor, click Add measurement, and then click Line.
  3. In the image, draw a measurement line of interest.
    The plot now shows the temperature profile along the drawn measurement line.
  4. If necessary, click the end points of the line and move them into new positions.
    Note how the profile plot changes as you change the position of the line.
  5. To change the temperature unit (Celsius, Fahrenheit, or Kelvin) or color of the plot, click Settings (the icon is located to the right of the plot).