A couple of fixes and docs improvements

[naymushin]

Before you go

Unless this is a simple fix (typos, bugs with obvious solution), please open an issue first so that we can discuss the best approach to address the problem. Without a reference issue and discussion, unfortunately, this PR will likely be ignored.

If the edited files were covered by tests, updated tests are required for merging. Please look into the tests folders and make sure you cover new code.

• Fixes: #1175 #1168
• Tests: no
• Docs updated: yes

Solution

The exception in #1175 was simply wrapped in try-catch block with a CameraException thrown from there. Both exceptions in #1168 are now prevented early with the assumption of the getData() method returning null values in rare cases.