Nao Pross authored Mar 14, 2022 and Jonas Schmid committed Mar 14, 2022

If for any reason (e.g. the camera has been disconnected) the data stream from the camera is no longer available, without these checks the entire python interpreter crashes with a nice segmentation fault.

These allow to handle the error from within Python with the following code snippet:

```
    try:
        o3000.video_images_get()
    except RuntimeError:
        # handle the error, e.g. try to restart the o3000 driver
```

Nao Pross authored Mar 14, 2022 and Jonas Schmid committed Mar 14, 2022

c_extension.c: initiate a Python exception instead of returning a NULL pointer in case only gray scale is available

Nao Pross authored Feb 11, 2022 and Jonas Schmid committed Feb 11, 2022

Improved solution to the issue described in commit

  1cfdf5c1

The new solution should be more OS-independent.
Tested on MacOS 12.1 and Debian 10 Buster.

Signed-off-by: Jonas Schmid <schmid@stettbacher.ch>

Nao Pross authored Feb 09, 2022 and Jonas Schmid committed Feb 09, 2022

On Debian Linux and its derivatives such as Ubuntu and LinuxMint, Python
packages installed through the package manager are kept in a different
non-standard directory called 'dist-packages' instead of the normal
'site-packages' [1].

To detect the Linux distribution the 'platform' library (part of the
Python stdlib) provides a function 'platform.freedesktop_os_release()'
that parses a standard file '/etc/os-release' available in most Linux
distributions [2]. However this function is rather new (Python >= 3.10)
and unavailable in most python installations, so the core of its
functionaly was reimplemented here.

[1]: https://wiki.debian.org/Python#Deviations_from_upstream
[2]: https://docs.python.org/3/library/platform.html#linux-platforms



Signed-off-by: Jonas Schmid <schmid@stettbacher.ch>

Pipeline using a Python C-Extension.