Why Video Compression Matters for Security Systems
Security camera systems record continuous video, 24/7, for months or years. The compression codec your cameras use determines how much storage you need and how much network bandwidth your system consumes. Choosing H.265 over H.264 can cut both requirements by 50% — without any reduction in visible image quality. For a 32-camera system, this difference translates to saving 10–20TB of storage over a 30-day retention period, or the difference between a 2-drive NVR and a 4-drive NVR.
How Video Compression Works (Simply)
Raw uncompressed 4K video generates approximately 3 gigabytes per second of data — completely impractical for surveillance storage. Compression codecs (like H.264 and H.265) reduce this by encoding only the changes between frames rather than storing every frame in full. A static hallway where nothing moves needs very little storage — only a handful of reference frames. A busy parking lot with constant movement generates much more data.
H.264: The Incumbent Standard
H.264 (also called AVC — Advanced Video Coding) was introduced in 2003 and became the dominant video compression standard for IP cameras through the 2010s. Most installed IP cameras worldwide use H.264. It produces good image quality at manageable bitrates and is supported by virtually every NVR, VMS, and viewing client.
Typical H.264 bitrate for 4MP camera: 8–12 Mbps
H.265: The Current Standard
H.265 (HEVC — High Efficiency Video Coding) was introduced in 2013 and achieves equivalent visual quality at approximately half the bitrate of H.264. Modern IP cameras (2020 and newer) from major manufacturers (Hikvision, Uniview, Hanwha) all support H.265 natively.
Typical H.265 bitrate for 4MP camera: 4–6 Mbps — approximately 50% less than H.264
H.265+ / Smart Coding: The Next Level
H.265+ (also marketed as Smart H.265 by Hikvision and similar names by other brands) is a proprietary enhancement that applies additional machine-learning-based compression in regions of the frame with no significant changes. In a typical surveillance scenario (mostly static background, occasional motion events), H.265+ achieves 70–80% bitrate reduction compared to standard H.264.
Typical H.265+ bitrate for 4MP camera: 1.5–3 Mbps — 75–80% less than H.264
Caveat: H.265+ is a proprietary format — cameras must be paired with compatible NVRs from the same manufacturer for the full compression benefit. Using H.265+ cameras with a generic ONVIF NVR may revert to standard H.265 or H.264 streams.
Practical Storage Impact
For a 16-camera system with 30-day retention, recording 24/7:
| Codec | Bitrate (4MP) | Storage (16 cameras, 30 days) |
|---|---|---|
| H.264 | 10 Mbps | ~64 TB |
| H.265 | 5 Mbps | ~32 TB |
| H.265+ | 2 Mbps | ~13 TB |
The difference between H.264 and H.265+ represents five 8TB hard drives — approximately $500–$600 in hardware savings, plus the NVR cost difference for a smaller drive bay count.
When H.264 Is Still Fine
If your existing camera system uses H.264 and records to an H.264-compatible NVR, there's no reason to replace functioning equipment just to use H.265. The codec difference matters at the design phase or when purchasing new cameras. If you're replacing an existing system, H.265 or H.265+ should be the default.
IDS CCTV Recommends H.265+
All new camera systems we design specify H.265+ cameras paired with compatible NVRs to maximize storage efficiency. This allows clients to achieve longer retention periods without additional hard drives. Contact us to discuss a storage-efficient camera system design for your property.
