I don't think that this "multi-billion pixel" camera is what you...

I don't think that this "multi-billion pixel" camera is what you think it is.

For example, Canon have just developed the worlds largest sensor for typical cameras. It is 120 Megapixels.

https://cpn.canon-europe.com/content/news/120_megapixel_apsh_format_cmos_sensor.do

The massive multi-billion pixel photo is simply a camera that takes multiple pictures and then joined by software into one large file?

This has been done many times in the past on rooftops by amateur and professional photographers.

Here is a link on how it is typically done:

https://petapixel.com/2015/02/21/a-practical-guide-to-creating-superresolution-photos-with-photoshop/

You could say that this is actually what Nearmap does. It stitches many photos into a huge array that all can view?