What is the role of frames per second or fps and what are the main differences with respect to the refresh rate.
When you play a video on a device, a sequence of images is used in rapid succession to give the impression of movement.
The term frames per second (abbreviated fps) expresses the number of images that appear on the screen in one second: they are enough for the human eye 30 fps to have the illusion of a continuous projection of the images. Below this threshold it is possible to notice the “detachment” between an image (frame) and the next one.
Going up with the value of frames per second you get a smoother video so much more natural.
The value of the frames per second is therefore the number of frame that the graphics card can send to the display every second.
Video game enthusiasts frequently use the term fps: a high value not only has an impact on the game experience and therefore on the rendering of the scene, but allows you to act with greater precision when aiming and defeating an opponent.
To check the frame rate i.e. the number of frames per second, you can press the key combination in Windows 10 and 11 Windows+G (Xbox Game Bar), click the button Performance top and finally check the value FPS (You may need to click the first time Request access then restart your PC to apply the change).
In addition to Xbox Game Bar il real-time fps count it can be activated by the NVidia or AMD video card driver, by software such as MSI Afterburnerdai client Steam, EA Origin e Ubisoft Connect.
Cameras, whether moving or stationary, work on the same principle: the lens opens for a period of time, light information is gathered by the photoreceptors, and an image is captured.
In the case of moving images, the sequence is typically digitally acquired between 24 and 60 fps: however, the obtainable performances vary considerably depending on the quality of the sensor, the resolution used, the format, the type of video and so on.
It is important to take into consideration the frame rate with which a sequence is acquired and the fps value to be obtained when reproducing the same content.
Take for example videos in slow motion or reproduced in slow motion: because, for example, in the specifications of a smartphone it is stated that it can record video 4K a 60 fps ma in slow motion si spinge a 240 fps?
Capturing a scene at 60fps that you then need to view in slow motion is only good if subject movement is limited – certainly not for situations where there’s a lot of action.
The faster the action is shooting, the higher the frame rate in the process of acquisition. To get smooth videos in super slow motion you should focus on 480 fps:
Slowdown Rate = Capture Frame Rate / Playback Frame Rate
If a video is shot at 240 fps and played back at 30 fps, the video is slowed down 8x.
When we talk about monitors, we generally use the term Hertz (Hz) by which the refresh rate: 1 fps equivale a 1 Hz.
Differences between frames per second and refresh rate
The refresh rate expresses how many times the PC monitor or any other display can update the image on the screen: in fact, we have also seen that a TV can be used as a monitor.
If the refresh rate is mainly related to the monitor and the fps value is mainly related to the graphics card power (GPU)the two concepts are in any case correlated with each other so much that one value directly affects the other and vice versa.
Taking into consideration the graphics card of a PC, this is called for example to perform the rendering of the frames that make up video games: the more powerful the GPU, the more the number of generated images can grow and the more the fps value increases.
The fps value may be forcibly limited in certain applications, such as games, to ensure that i frame remain consistent.
However, the graphics card can also be called a decode a media stream, like that of a video. Also in this case the type of video stream and the skills in the decoding phase allow to obtain a higher fps value.
Using a program such as VLC, opening a multimedia content, starting its playback, pressing CTRL+I then clicking on Encoder, you get the number of frames per second. Here this value obviously does not reflect the “potential” of the monitor and video card but indicates the preferences chosen in the sampling and coding phase.
Together with a properly chosen bitrate and resolution, the fps value ensures that a quality video can be obtained and conveyed.
If the graphics card is the source of new frames, the monitor is the recipient: the fps value is limited to whatever the refresh rate of the monitor.
Even if the graphics card were able to handle 144 fps, by connecting a monitor that cannot go beyond 60 Hz, the maximum fps value obtainable will automatically drop to 60 fps: this is the situation that leads to the phenomenon known as screen tearing. In these cases a single frame displayed on the screen contains information from two or more frames highlighting artifacts.
The technologies VRR (Variable Refresh Rate) they take care of dynamically adapting the refresh rate of the monitor to the signals of the graphics card, thus avoiding phenomena of screen tearing.
Obviously if you have a good graphics card it’s essential to make sure your monitor isn’t wasting its potential. The same observation applies in reverse: an excellent monitor must act as a counterpart to a graphics card of the same level. Ideal would be to try to match fps and Hz.
The HDMI or DisplayPort connection is also important: HDMI 2.1 cables allow for example to transfer 10K video at 120 fps. In another article we see the main characteristics of DisplayPort and the differences between the various versions, currently used mainly in the IT field and not on the multimedia side.