The primary focus of the Swiss QR Code Validation.Portal is the validation of the data structure of the QR-Code Payload and not testing of QR-Code Images or complete QR-Invoices.
Image validation (of jpg-, png- and img-files) may not work in any case. This is due to influences of various parameters (e.g. used QR-Libraries, complexity of the created QR-Codes, image resolution, etc.). Validation of PDF-files is not supported because of the added complexity to detect the correct image containing QR-Code within the pdf-file.
The software scanner that we are using to decode the QR-image is less precise and reliable than hardware based scanning devices (like dedicated scanners or smartphones).
But you can be sure that your created QR-code is correct and will work if your QR-payload has been successfully validated on the Validation.Portal.
We therefore recommend to stick to the validation of plain text files containing the QR-payload.