In the first bar, a Cmaj7 arpeggio is depicted starting on the 6th string, from the note B (the 7th of the arpeggio), followed by the note C (the root). This is the convention we shall use for this discussion -- 7th, Root, 3rd and 5th.
By dropping the 7th below the root -- instead of starting on the root -- we can play any 7th arpeggio using only two strings.
On the 5th string, we find the note E (the 3rd) at the 7th fret, and G (the 5th).
We can then repeat the same fingering on string set 3 and 4 and string set 1 and 2, as shown, yielding a 3-octave Cmaj7th arpeggio.
In the second bar, a Cm7 arpeggio is shown, with E's and B's flatted appropriately, and played across the same string sets.
For dom7th arpeggios, apply the b7, Root, 3rd and 5th formula to the fingerings. Similarly for m7b5 arpeggios, apply the formula b7, Root, b3 and b5.
I'll leave you to work out the diminished and augmented 7th arps for yourself.
This method breaks the convention of learning 7th arps that use traditional assymetrical fingerings which can be difficult to incorporate when improvising.