To verify your ID document, there are a few points you want to consider.
1. Only have the relevant information area in the image
If you are taking an image of your passport, then make sure that only the information page of the passport is in the image. Same goes for driver's license and health card. You want to have the border of the image.
2. All text must be sharp, clear and readable
The text must be sharp, so that is easy to read the different text elements. Note that the text in all of the image must be sharp.
3. Avoid obstructions on the image
No objects can be covering elements the image. Especially important is it, that no text and security elements are obstructed. A common mistake is to cover elements with your fingers, so be extra careful of this.
4. No glares or reflections
Be careful of the lighting conditions when taking a photo of your documents. Lighting is a common culprit of images that cannot be verified, so be extra careful of the lighting conditions. Ideally, you should use a well-lit area to take the image in.
5. Use a simple background for the image
Make sure to use a plain background that ideally contrasts to the edges of your document (so that it is easy for a system to distinguish where the document borders are. We recommend placing the document on a single-color tabletop when taking the image.
6. The document has to be valid (i.e. not expired)
When verifying a document, the system also verifies the content of the document. For example, if the expiration date has been reached, then the document is also considered invalid.