Creating an image verification point
You can use an image verification point to test images in your application. When you record the verification point, a baseline image file is created. Every time you play back the script, the image is compared to see whether any changes have occurred, either intentionally or unintentionally.
Starting from 9.1.1, enhancements have been made to image verification points. Prior to 9.1.1, image verification was strictly a pixel-to-pixel comparison. When a script was recorded on one computer and played back on another computer, the image verification point sometimes failed because of system-level differences, such as screen resolution or differences in the operating system. Now, if a pixel-to-pixel comparison fails, a new image-based algorithm is applied that is more tolerable to minor changes to the image.
The algorithm returns an integer from 0 to 100 that reflects how much the two images
correlate. By default, anything above 80 (or 80% correlation) is considered a pass.
You can customize this percentage by adding a
rational.test.ft.image.correlationaverage
flag in the
ivory.properties file, for example:
rational.test.ft.image.correlationaverage=70
In this example, anything above 70% correlation is considered a pass.
Starting from 9.1.1.1, IBM® DevOps Test UI (Test UI) includes support for using Optical Character Recognition (OCR) with image verification points. This allows you to capture text along with the image.