Storage calculation is very important for CCTV projects. I bet you want to learn how to calculate bandwidth and storage for your IP cameras and recorder devices, so you can estimate how much hard drive is necessary to record your CCTV footage. So it's time to learn, just keep reading...
Got a question about CCTV storage?
Yeah, I know... you are about to purchase a CCTV system but you have no idea how to calculate the necessary storage to record the camera footage. "What hard drive should I buy? How long can my DVR record for ?" If those are some questions you are asking right now, don't worry I have the answer.
Calculate the storage before go shopping
The correct time to work on the storage calculation is when your CCTV project is still on paper, Wait,,,, your already purchased your cameras and recorders? Don't worry, you still will benefit from reading this article...
Let's say you have a DVR (Digital Video Recorder) with 1 or 2 TB hard drive for video storage, guess what... you are good to go. It doesn't matter if it's a 4, 8 or 16 channel DVR, you can adjust the configuration and record videos for about 7 to 30 days or even longer period of time. But 30 is a good number.
30 days is enough for most projects...
OK, I've heard people asking for one year CCTV recording project. Although that can be possible, it's not a typical situation because the project can become quite expensive for such a long time video recording.
1st method for the storage calculation
Let's use a simple method to calculate the storage for your CCTV project, you just need to know how much bandwidth your security camera is using and that is the same as saying what's the bitrate for your camera.
If you are planning to use your camera with HD resolution a 1024 Kbps bitrate will be OK, for Full HD resolution use 2048 Kbps as your bitrate.
With that information you can use a formula or a storage calculator to input the bitrate, the number of days for recording and the number of cameras
If you are in a hurry, here's the formula
Desperate looking for a CCTV storage calculation formula ?
There are more theory about CCTV storage calculation, but if you are really crazy about math and want to see the formula, here you go....
Storage = ( (cam_bitrate/8) * 3600 * 24 * Qty_cam * Qty_days ) /1G
OMG.,,, It's a big formula, isn't it ? Don't worry that's easy stuff, just take a look at the example and you will understand how to use this formula.
Storage calculation formula example 01
1 camera with bitrate of 1024 Kbps recording for 1 day
Storage = ( (1,024.000/8) * 3600 * 24 * 1 * 1) / 1,000,000,000
Storage = 11 GB
Storage calculation formula example 02
10 cameras with bitrate of 2048 Kbps recording for 30 day
Storage = ( (2,048.000/8) * 3600 * 24 * 10 * 30) / 1,000,000,000
Storage = 6,635GB (or 6.35 TB)
So how was that storage calculation formulla ? Did you understand it ?
I'm using the camera bitrate for the calculation, that means I know how much bandwidth the camera is using for the quality it was configured for.
In the example number 1, the camera bitrate is 1024Kbps, that means it is using around 1,024,000 bps or 1Mbps to record the video.
In the example number 2, the camera bitrate is 2048Kbps, that means it is using around 2,048,000 bps or 2Mbps to record the video.
In the second example the camera uses more bandwidth (and storage) because probably its configured to to have higher video quality.
For those who hate formulas
OK, you hate math and all those storage calculation formula, don't you ?
You still need to calculate the camera storage, and are wondering if there's a easy way, perhaps you could use a CCTV bandwidth and storage calculator
Is there something like this available to help you with your CCTV project?
Yes, my friend... there's some CCTV bandwidth and storage calculator out there that can make your life much easier, so let's talk about them.
IP video system design tool
This bandwidth and storage calculator it's easy to use, let's jump directly to the example we used before. In the example number 1 there's one camera using 1024 Kbps with one day recording, right ?
So, take a loot at the picture below, that's exactly what I put into the field in the red squares.... 1 Day, 1 Camera, 1024 Kbps can you see the result ?
Yes my friend, it's exactly the same I got before with the formula it's a total storage of 11GB, look at the Disk Space field and you gonna see it.
Click the link below to download the software
What affects bandwidth and storage
The higher the camera resolution, the greater the need for bandwidth and storage space, some common IP camera resolutions are: QCIF, CIF, 2CIF, 4CIF, VGA, SVGA, HD, Full HD and 4K.
30 FPS is considered real-time motion and shows smooth movement on the recorded video, but if you setup your camera with such frame rate, the use of bandwidth and storage will increase a lot. So for most CCTV projects 15 FPS is enough.
CODEC (compression algorithm)
The choice of the codec dramatically influences the amount of hard disk used for recording, so using modern algorithms like H.264, H.264 plus and H.265 can save more recording space when compared to the old CODEC such as MJPEG or MPEG-4 for example.
If the scene where the camera is installed is very complex, ie there is a lot of movement of people and objects, the need for more bandwidth and storage space will increase.
Continuous or event recording
When you set up a CCTV recorder, you can choose whether videos will be continuously stored even when there are no events in place, or whether the recording will start only when there is an event such as motion detection.
Another software for CCTV storage calculation
See below an example of a CCTV storage calculation using a software from the company Hanwha Techwin (former Samsung Techwin).
For the storage estimation, let's say there are 10 cameras, recording for 30 days in Full HD resolution with 15 FPS, using the H.264 CODEC in a scene with high activity and recording by event 60% of the time
Click the link below to download the software
Can you see how powerful is storage calculator like this one ? Take a look at every one of those number, those are important information as follow:
1. Good resolution (Full HD)
The camera is using 1920x1080 resolution, that's is a higher one, also known as Full HD or 2MP (Mega Pixel). Very common on modern IP cameras.
2. No robotization please use 15 FPs
Here the I'm using 15 FPS, that's enough to make video scene looks smooth and without that annoying "robotization effect", do you know what I mean ?
If you use a low frame rate such as 5 FPS you certainly is going to notice the moving objects, people, cars, etc with that small "frame to frame jumps" that what I mean by "robotization effect", so keep the frame rate at 15 FPS.
3. Compress that video before recording
By using the H.264 CODEC the camera will compress the video without sacrifice too much the quality. Nowadays there's the H.265 CODEC that is a better option, but it's not available it this camera model,
4. A lot of people walking around
If the environment is too busy, let's say something like a mall or store that'll be a lot of movement, so there will also be more events and more recording.
Take a look at the configuration and you will notice that it was setup to high.
5. Open the mall all day long
How often there'll be movement in front of the camera during the day ? Let's say in a mall that opens for 12 hours a day the event frequency is 50%, just to be safer let's estimate 14 hours a day, so that's 60% of the time.
Storage calculation results
With this calculation, we know that it necessary 2.77 TB of storage for a period of 32 days and 11 hours, considering that in the store there's movement for a maximum of 14 hours a day.
So let's just use a 3TB disc for the recorder, which allows extra recording time for the this small CCTV project.
As you can see, it is nothing so complex, it's no rocket science and you can do it. But remember this is a storage calculation with an overall estimation.
After 30 days of actual recording, it's possible to make sure that the system is recording in accordance with the projected, as long as the recorder can keep at least 30 days of footage everybody will be happy 🙂
So congratulation for your CCTV project and storage calculation, you can use the tools to practice and make sure you learnt everything.
Want to become a better professional ?
If you want to become a professional CCTV installer or designer, take a look at the material available in the blog. Just click the links below:
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Claudemir Martins is a former Samsung Engineer with 19+ years of experience in the surveillance industry. He has been traveling around 17 different countries to teach people how to design, and install CCTV systems. He is currently working for Axis Communications as a Technical Services Engineer and living in the United States with his family.