We are currently investigating an issue related to HTTP 413 errors and would appreciate your assistance in clarifying the behavior of the ImageUtility component.

Background

We have observed the following:

HTTP 413 errors are being logged in OutSystems.

IIS logs show 413.1 responses.

The request size sent from the client is approximately 17.3 KB.

IIS MaxAllowedContentLength is configured to approximately 134 MB.

Based on the above, the request size does not appear to exceed the configured IIS limit. During our analysis, we noticed that the issue occurs when the ImageUtility.ResizeImage action is executed.

Questions

Could the ImageUtility ResizeImage action be a contributing factor to the HTTP 413 errors we are observing?

We would like to understand whether any internal processing performed by the component could result in a 413 response.

Are there any scenarios in which the image size may increase after the ResizeImage action is executed?

For example:

　・Image format conversion

　・Re-encoding of the image

　・Compression or quality settings

　・Any other internal image processing

Could you please confirm whether it is possible to determine the image size before and after the ResizeImage action for the affected requests?

Are there any known limitations, issues, or best practices regarding the use of ResizeImage that could be related to this behavior?

Since the original request size is relatively small compared to the configured IIS limit, we would like to better understand whether the image processing performed by ResizeImage could have any impact on the generation of the HTTP 413 errors.

We appreciate your support and look forward to your feedback.

Best regards,