CCTV recording storage depends on resolution, frame rate, compression format, bitrate, and recording time.
CCTV video recording is a common security method used to monitor and record activities in specific areas.
With the development of surveillance technology, more businesses and homeowners are using CCTV cameras to protect their property and improve security. However, many users are not sure how much storage space is required for one day of video recording.
This article explains the main factors that affect CCTV storage capacity and how to estimate daily storage requirements.
1. What Affects CCTV Recording Storage?
To calculate CCTV video storage, several key factors need to be considered:
- Resolution
- Frame rate
- Compression format
- Bitrate
- Recording time
- Number of cameras
- Resolution refers to the clarity of the video image, such as 720p, 1080p, 4MP, or 8MP.
- Frame rate refers to how many frames are recorded per second. Common frame rates include 15fps, 25fps, and 30fps.
- Compression format refers to the video compression technology used to reduce file size. Common formats include H.264 and H.265.
- In general, higher resolution, higher frame rate, and longer recording time will require more storage space.
2. Storage Calculation Method
The easiest way to estimate CCTV storage is to calculate based on the video bitrate.
A common formula is:
Storage per day = Bitrate × 3600 seconds × 24 hours ÷ 8 ÷ 1024
The result is usually shown in GB per day.
For example, if a camera records at a bitrate of 4 Mbps:
4 Mbps × 3600 × 24 ÷ 8 ÷ 1024 ≈ 42 GB per day
So one 4 Mbps camera may need about 42 GB of storage for one day of continuous recording.
3. Example Calculation
Suppose we have one CCTV camera with the following settings:
- Resolution: 1080p
- Frame rate: 30fps
- Compression: H.264
- Recording mode: Continuous recording
- If the video size is about 100MB per minute, then:
- 100MB × 60 minutes = 6000MB per hour
- 6000MB is about 6GB per hour.
- For 24 hours of continuous recording:
6GB × 24 hours = 144GB per day
In this case, one camera may need about 144GB of storage for one day.
However, this is only an example. Actual storage usage may vary depending on bitrate, compression, image complexity, and recording settings.
4. H.264 vs H.265 Storage Usage
Compression format has a big impact on storage capacity.
H.264 is widely used and offers stable video quality, but it usually requires more storage compared with newer compression formats.
H.265 can reduce storage usage while maintaining similar image quality. In many cases, H.265 can save about 30% to 50% of storage compared with H.264, depending on the scene and device settings.
For long-term recording, H.265 is often a better choice if the camera and recorder both support it.
5. Continuous Recording vs Motion Recording
Recording mode also affects storage usage.
Continuous recording means the camera records 24 hours a day. This requires more storage space.
Motion recording only records when movement is detected. This can greatly reduce storage usage, especially in areas with low activity.
For example:
- Busy shops may still require large storage capacity.
- Warehouses at night may use much less storage with motion detection.
- Offices may save storage outside working hours.
- Choosing the right recording mode can help reduce storage cost.
6. Choosing the Right Storage Device
After estimating the required storage space, users can choose a suitable storage device.
Common storage options include:
- Surveillance hard drives
- SSDs
- NVR built-in storage
- Network storage devices
- Cloud storage
- For most CCTV systems, surveillance-grade hard drives are commonly used because they are designed for long-time video recording.
- If the system has multiple cameras or requires long retention time, such as 15 days, 30 days, or 60 days, a larger-capacity hard drive or network storage solution may be needed.
7. Conclusion
The storage capacity required for CCTV recording depends on resolution, frame rate, compression format, bitrate, recording mode, number of cameras, and recording time.
A single 1080p camera may require dozens of GB per day, while higher-resolution cameras may need much more storage.
To estimate storage more accurately, users should check the camera bitrate and recording settings.
By selecting the right compression format, recording mode, and storage device, users can build a more efficient and reliable CCTV recording system.