Compression is the boring part of CCTV that saves you money.
Most people never think about video compression. But it directly affects two things you care about: how much storage you need and how smoothly remote viewing works. Choose the wrong compression, and you'll run out of hard drive space or deal with constant buffering.
This guide explains the two most common compression standards — H.264 and H.265 — in plain language.
What is Video Compression?
Raw video files are huge. A single hour of uncompressed 1080p footage could take up hundreds of gigabytes. Compression reduces the file size while trying to keep the image quality as high as possible. It's like zipping a file, but for video.
Without compression, CCTV would be impractical. With good compression, you can store weeks of footage on a single hard drive.
H.264 (AVC) — The Old Standard
H.264 has been around for over 15 years. It's reliable, widely supported, and works on almost every device. For 2MP and 4MP cameras, H.264 still does a decent job.
The downside? H.264 is not very efficient by today's standards. It uses a lot of storage and bandwidth compared to newer codecs.
H.265 (HEVC) — The Modern Standard
H.265 is the successor to H.264. It's roughly twice as efficient — meaning it can deliver the same visual quality at half the bitrate. In practical terms, an H.265 camera uses about 50% less storage and 50% less bandwidth than an equivalent H.264 camera.
For 8MP and higher-resolution cameras, H.265 is almost essential. Without it, the storage and bandwidth demands become unrealistic.
Quick Comparison
| Feature | H.264 | H.265 |
|---|---|---|
| Compression Efficiency | Good | Excellent (about 2x better) |
| Storage Usage | Higher | ~50% less |
| Bandwidth Usage | Higher | ~50% less |
| Image Quality at Same Bitrate | Good | Better |
| Device Compatibility | Universal | Mostly modern devices |
| Best For | 2MP–4MP, older systems | 4MP–8MP+, new systems |
What About H.264+ and H.265+?
Brands like Hikvision and Dahua have their own "smart" versions — H.264+ and H.265+. These are enhanced versions of the standard codecs that further reduce storage and bandwidth by dynamically adjusting compression based on the scene. They can save up to 70% compared to standard H.264, but they work best with the same brand's cameras and recorders.
Which One Should You Choose?
If you're installing a new system, go with H.265. It's the modern standard, and the savings in storage and bandwidth are significant — especially for 8MP cameras or systems with many cameras.
If you have an older system that only supports H.264, don't panic. You can still get good performance. Just be prepared to use a larger hard drive or motion-based recording to manage storage. See our storage guide.
Not sure which compression your system needs?
Book a free site survey. We'll recommend the right recorder and cameras for your storage and bandwidth requirements.
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Frequently Asked Questions
H.265 is about twice as efficient as H.264. It provides similar quality at half the bitrate, which means half the storage and bandwidth usage.
Not really. H.264 is fine for 2MP cameras. H.265 becomes more important for 4MP and essential for 8MP.
Most modern phones support H.265. If your phone is very old, you may need to use H.264 for compatibility. We can configure this during installation.
Yes, in many cases. Most NVRs support both codecs simultaneously. We can advise during a site survey.
No. H.265 maintains similar or better quality compared to H.264 while using less data. That's the point.
H.265+ is a smart version by Hikvision that further reduces storage and bandwidth by adjusting compression dynamically. It works best with Hikvision equipment. See brand options.