💡 Key Highlights & Expert Takeaways
- ● Modern H.265+ compression reduces storage consumption by 50% compared to older H.264 codecs.
- ● A 1TB hard drive holds roughly 8 to 10 days of continuous recording for 4 Full HD (2MP) cameras.
- ● Enabling motion-triggered recording instead of continuous recording can double or triple storage retention days.
- ● Always use dedicated surveillance hard drives (e.g. WD Purple, Seagate Skyhawk) rated for 24x7 write workloads.
Key Factors Governing Video Storage
How many days of video history your system stores before overwriting depends on three technical factors:
- ✓ Camera Count & Resolution: 4MP cameras produce double the data stream of 2MP cameras.
- ✓ Video Compression Codec: H.265 and H.265+ use smart predictive encoding to dramatically shrink file sizes during static hours.
- ✓ Recording Mode: 24/7 Continuous recording vs. Motion Detection recording (records only when movement is sensed).
Surveillance Hard Drive Capacity Chart (H.265 Compression)
Reference this estimated retention chart for continuous 24/7 recording at 15-20 frames per second:
| Camera Count | Camera Resolution | 1TB HDD | 2TB HDD | 4TB HDD |
|---|---|---|---|---|
| 2 Cameras | 2MP Full HD (1080p) | ~18-22 Days | ~36-45 Days | ~75-90 Days |
| 4 Cameras | 2MP Full HD (1080p) | ~8-11 Days | ~18-22 Days | ~38-45 Days |
| 4 Cameras | 4MP Quad HD (2K) | ~4-6 Days | ~9-12 Days | ~20-25 Days |
| 8 Cameras | 2MP Full HD (1080p) | ~4-5 Days | ~9-11 Days | ~18-22 Days |
| 8 Cameras | 4MP Quad HD (2K) | ~2-3 Days | ~5-6 Days | ~10-13 Days |