Ranorex Forum

Hi there,

I'm currently trialling Ranorex for a web based data analytics product. Because a lot of our site is visual, I'm using the Image Validation test to check that, e.g. charts appear correctly.

One thing that is likely to happen is that the charts might change subtly over time, but still basically be OK. I've figured out how to reduce the similarity threshold (although there is no way to do this globally as far as I can tell, so it's a bit annoying to do it for each verification step).

Even so, I'm assuming the images will be wrong quite regularly.

I can see the failed images in the report - which is very cool - but it really feels like it's missing a button to say "use this new image". At the moment it seems like I have to replay the test and stop at each failed image to capture the new correct image.

Is there a better way of doing this?

Thanks!

John

Hello John,

The default value for the image similarity can be changed in the Global Settings.
Note that this only affects new recorded image based validations. Existing validation steps have to be changed manually.

If the validation fails, I would suggest enabling the Report Similarity, which will log the actual similarity value. This could be changed in the properties grid of the validation action.
Unfortunately, there is no other reliable way than updating validation screenshots manually.
More information about image validation can be found in the blog entry Enhanced Features of Image Validation.

If you need more information, please do let me know.

Sincerely,
Johannes

Thanks - that's super helpful!

Is there any technical information about the image similarity algorithm used?

John

Hello John,

Unfortunately, there is no public information about the algorithm, which is used to compare images.
All available information about image-based automation can be found in the mentioned blog entry and in the User Guide.

Thank you for your understanding.

Sincerely,
Johannes

OK, no worries, thanks for the info.