Easier Image Comparison with TestComplete 8.10

  January 14, 2011

Many applications include graphical and custom-drawn objects — charts, graphs, maps, themed UI elements, images, and so on. TestComplete allows you to verify that these objects are displayed correctly in your tested application and provides region checkpoints for you to perform these kind of checks as part of your automated test. (For those who are not familiar with these checkpoints, here’s a quick Image Checkpoints video to get started).

With TestComplete 8.10, we’ve added a number of improvements to region checkpoints to make it easier to set them up. Here are the highlights of the changes.

Adjusting acceptable image difference made easier

Region checkpoints perform a pixel-by-pixel comparison of images, and by default fail on even a single pixel difference. Sometimes these small differences (such as slightly different shades of the same color or selection frame) are simply insignificant, and you may want your tests to also ignore these differences.

For this purpose exactly, region checkpoints have the Pixel Tolerance and Color Tolerance parameters — they allow you to indicate the acceptable differences between the actual and expected images. You can read more about these parameters at these links:

We wanted to make it easier for you to find suitable tolerance values and reduce the trial-and-error adjustments, so we added a handy little feature. Now, when your test fails because of a minor image difference, go to the image comparison report, open Additional Information and click Adjust the checkpoint parameters to make the next comparison successful.

TestComplete will analyze the pixel and color differences between the expected and actual images and calculate the comparison tolerance values that would enable the checkpoint to ignore the allowed differences. Moreover, if you’re using keyword tests, TestComplete will offer to automatically update the checkpoint parameters for you.

Adjusting region checkpoint parameters

Sliders for specifying comparison tolerance values

We’ve also improved the interface of region checkpoint settings and added sliders for the Pixel Tolerance and Color Tolerance parameters. Now you can set the tolerance values by simply dragging the sliders to the desired level. No more working out the boundary and relative values!

Sliders for specifying comparison tolerance values

New editor for image comparison mask

Another cool feature of TestComplete’s region checkpoints is masking specific areas of the image, so that they are ignored during the comparison. This is useful for ignoring dynamic elements on the screenshots, such as current date/time, form field values, web page banners and so on.

In TestComplete 8.10, we’ve added a built-in editor for image comparison mask, so that you no longer have to use an external image editor and remember how to color-code the mask. You can simply select and ”delete“ image areas you want the checkpoint to ignore, zoom in the mask and touch it up using the pencil tool, undo and redo changes and much more. Besides creating a mask from scratch, you have the option to load and edit an existing mask image stored in your test project.

Image comparison mask editor

These are just a few of all the new features packed into TestComplete 8.10. Stay tuned to find out more, or even better, download TestComplete 8.10 and try it out for yourself. We’re always happy to receive feedback, so let us know what you think!