We use a 4 port video capture card ($150) and a computer to create a Linux zoneminder security platform.

04:08.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11)
04:08.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11)
04:09.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11)
04:09.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11)
04:0a.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11)
04:0a.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11)
04:0b.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11)
04:0b.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11)

This is the card I use.
I find it locks if I define zoneminder monitors above about 7fps, probably due to the limitations in the old PCI buffer this card uses. I run it in a server with mostly pci-e cards so these old slots are getting hard to find.

First cam: Tinycam
SourceType Local Function Monitor eneabled Maxumum FPS 7 Alarm Maxium FPS 7
source /dev/video0 device channel 0 device format ntsc capture palette rgb24
384×288
Normal orientation
timestamp: %%s - %y/%m/%d %H:%M:%S
ZM FAQ

Zone Minder Manual

• Monitor
• modect
• record
• mocord
• nodect

TODO:
. find pci-e capture cards this inexpensive
. figure out various zoneminder monitor modes
. remote rsync of various video incase of onsite disastor