This document is most helpful for the site designer and on-site installation personnel.
Common IP video resolutions by Pixel count
Pixel Count refers to the number of pixels contained in an image sensor, or that a captured photograph is made up of. The higher the number the more information there is. Pixel Count is usually defined in Megapixels.
A megapixel (MP) is a million pixels; the term is used not only for the number of pixels in an image but also to express the number of image sensor elements of digital cameras or the number of display elements of digital displays.
The suggested minimum resolution is 1920x1080 resolution. Therefore, when it comes to image sizes, there are two main resolutions for the HD specification, 720p (1280×720, just less than 1-megapixel) and 1080p (1920×1080, 2.1-megapixel).
FPS / Frame rate is the speed at which those images are shown, or how fast you “flip” through the book. It's usually expressed as “frames per second,” or FPS. So if a video is captured and played back at 24fps, that means each second of the video shows 24 distinct still images. In other words, “ The speed at which they’re shown tricks your brain into perceiving smooth motion”.
Why does frame rate matter?
Frame rate greatly impacts the style and viewing experience of a video. Different frame rates yield different viewing experiences, and choosing a frame rate often means thinking about multiple factors; such as how realistic you want your video to look or whether or not you plan to use techniques like slow motion or motion-blur effects.
For example, Hollywood-style movies are usually displayed at 24fps, since this frame rate is similar to how we see the world and creates a very cinematic look. Live videos or videos with a lot of motion, such as sporting events or video game recordings, often have higher frame rates because there’s a lot happening at once. A higher frame rate keeps the motion smooth and the details crisp.
On the other hand, people who create animated GIFs will often sacrifice detail for smaller file sizes and choose a low frame rate.
How do I choose the best frame rate for my video?
First of all, there is no such thing as the “best” frame rate. As stated above, different frame rates yield different results, so selecting the best one means going with the option that best fits what you’re trying to create.
Even though the frame rate is a relatively straightforward concept, there’s a fair amount of controversy around which rates provide the best viewing experience, and there’s research that builds the case for just about any frame rate.
How many Frame per second is good for security Cameras?
Frame rate (expressed in frames per second or fps) is the frequency (rate) at which consecutive images called frames appear on a display. The term applies equally to film and security cameras, computer graphics, and motion capture systems. Frame rate means the number of frames that your surveillance camera captures per second. The frame is a concrete image within a succession of these that constitute an animation. The continuous succession of these frames produces the idea of movement, which happens because of the minimum differences between them. These have a frequency, which is the number of frames per second (fps) that is needed to get an idea of the movement. Maintain the quality of images while reducing bandwidth by choosing the best frame rate for security cameras. Keep reading to learn how many frames per second are good for a security camera system.
Best Frame Rate for Security Cameras
Frames per second is a way of measuring how many frames your Security Camera System records per second of video. For example, if your security camera captures 30 fps, it means that it can capture 30 frames in a single second of video. The higher the frames, the smoother the video will be. How many frames per second is good for a security camera? Security cameras with slow speeds (from 1 to around 25 frames per second) appear choppy, however, when presented with speeds of 25fps and higher it’s increasingly difficult to see individual frames. Currently, the industry standard for clear, smooth video even with moving objects, and the best frame rate for security cameras is 30 fps, although the quality of video you’re hoping to capture and your network’s bandwidth is heavily influenced by what frame rate will work best for you. 30 fps is not only the best frame rate for security cameras but, also, the standard rate for your television, since it results in smooth movement of people and objects between frames.
Frame Rate vs. Bandwidth
Frame rates still apply and translate with IP cameras, but instead of just looking up the max frame rate on the spec sheet, finding an IP camera’s potential frame rate involves a little more math. Each resolution records a range of available bitrates. The higher the bitrate, the higher the quality. Each Resolution also has a maximum bitrate that it can’t exceed. Your SD and HD analog cameras are identical when it comes to this, but these bitrates play a much larger role with IP cameras. At 2 megapixels, your IP camera will require a bitrate of around 10,000 Kb/s to record at its highest quality; this is the camera’s bandwidth requirement at this resolution. While this doesn't tell you how many frames per second you’re going to get, it gets you headed in the right direction of finding out. The other determining factor will be the bandwidth requirements of the remaining cameras in the system, and the big one will be the incoming bandwidth on your Spot Dashboard.
Incoming Bandwidth
The amount of incoming bandwidth your NVR is working with is printed right up front for you on the spec sheet. While your security cameras are measured in kilobits per second (Kb/s), your NVR’s incoming bandwidth will likely be measured in megabits per second (Mb/s); the conversion is simple enough. An incoming bandwidth of 80 Mb/s is pretty standard among smaller standalone NVRs. Converted to camera terminology, this means the NVR has 80,000 Kb/s of usable bandwidth on that Spot Dashboard. If your 2-megapixel cameras are using 10,000 Kb/s apiece, then you’ll be able to have as many as eight of them, while maintaining those cameras’ highest recording capabilities. Whether the highest available frame rate of your camera is 20fps or 30fps, you’ll be able to achieve that in this scenario. However, if your NVR allowed for it and you were to exceed eight cameras on the recorder, you would no longer be able to record at the maximum number of frames per second on all cameras anymore. Your options at this time would be to attempt slowly lowering the bitrate to accommodate for the extra camera, or to simply lower the frame rate on some or all cameras so that your system once again meets the bandwidth requirements.
Lowering the Bitrate
Lowering the bitrate can sometimes be your solution if you find yourself in need of one. Lowering the bitrate of your cameras will mean lowering the amount of bandwidth they require, but as we've made clear, this is linked to the camera’s picture. By lowering the bitrate at which the camera’s recording at, you’re also reducing that camera’s image quality. In small doses, reducing these bitrates can solve your issue, and the degradation in image quality can potentially go unnoticed. In other cases, you might find that something more extreme is needed to avoid neutering your high-definition picture.
Lowering the Frame Rate
In cases where reducing the bitrate wasn’t a viable option, reducing the number of frames per second at which the camera is recording is your last option. A full 30fps has become what the vast majority of the market has come to expect because of how much more mainstream it has gotten in the CCTV industry over the last few years. For even mid-sized IP camera systems, this can sometimes be hard to achieve; this is, of course, all related to available bandwidth. While lowering the frame rate might not seem like a lot of fun, the good news is that most people don’t realize how absurd it usually is to be recording all of those frames. In a lot of instances, you’ll find that recording at even just 7fps is enough to capture almost anything moving at a standard rate of speed. Unless you’re looking for an extraordinary amount of detail in a quickly moving object, there is nothing wrong with recording at 1 to 15 frames per second.
What are MBR and ABR?
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Back to defining the terms. Thinking about the above scenario, you may have had a choice at the beginning when you were selecting your movie to choose the hi-definition (HDX, HD) or standard definition (SD) format. Let’s say you decided to purchase the HDX version, or the highest quality possible (HDX video is streamed at 1080p and 24 frames per second). Your streaming service probably ran a background test at purchase time and determined that the HDX version will work on your network.
But the streaming service doesn’t know that 30 minutes into the movie, your kids and their friends all started watching YouTube videos over the same internet connection. The technical term for what you just experienced is MBR (Multi-bitrate). With MBR, a few different streams, all with different bitrates, are made available to the user. As the user clicks Play, the system performs a test to determine which bitrate is best suited for their situation. Once selected, however, the system will keep using that bitrate even if the internet connection or bandwidth fluctuates.
With YouTube or Netflix, as opposed to pay-per-view, you select a video and watch it right away. Upon initial viewing, you may get one bitrate, and as the internet connection fluctuates (kids, friends, other YouTube videos), the quality changes and usually becomes worse if the internet connection is heavily used. It will then change again minutes later once the internet connection is freed up (kids, friends have left the house). The streaming service detects the bandwidth fluctuations and automatically changes the bitrate for you so the movie continues without buffering. This is called ABR (Adaptive bitrate).
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