What is Video Frame Rate?

Video frame rate, or simply frame rate, is the number of individual frames or images displayed in one second of video. It is also referred to as frames per second (FPS).

You can think of a video as a series of images, called frames, captured by a camera in quick succession. When these frames are played back on the screen, they create smooth motion video, but in reality, these are individual images or frames.

For example, if the video frame rate is 30fps, then 30 images or frames are displayed one after the other in a second to create a fluid motion.

What is an appropriate video frame rate?

Video frame rate is a crucial aspect of video production that determines how smooth and realistic motion appears on the screen.

When we see any moving object in real life with the naked eye, such as a car being driven on a road or a football being passed from one player to the other, we see a certain amount of motion blur. Ideally, the frame rate you choose for your video should mimic this natural motion blur as closely as possible, making the viewing experience realistic.

If the FPS is too high, the video will show far too many details than what we are used to seeing with the naked eye, making the video look odd. If the FPS is too low, the video will look choppy.

What are some key frame rates and their uses?

Some standard frame rates include 24fps, 30fps, and 60fps, each serving different purposes and creating distinct visual effects. Let's look at these in more detail.

• 24fps: This frame rate is used in cinematic videos & film production. It provides a natural motion blur that mimics how the human eye perceives movement, making it ideal for movies and scripted TV shows. The 24fps rate is the minimum required to achieve smooth motion without appearing choppy​.
• 30fps: Traditionally used for television broadcasts in regions with 60Hz power systems, such as North America and Japan, 30fps offers a slightly smoother look than 24fps. It is commonly used for TV shows, live broadcasts, and sports because it can handle fast-moving scenes more effectively.
• 60fps: This higher frame rate is frequently used for video games, sports, and other fast-action content. It provides ultra-smooth motion and reduces motion blur, essential for detailed and dynamic scenes. It is also increasingly used for high-definition and 4K video recording, offering a more lifelike and immersive viewing experience.
• 120fps and above: These frame rates are typically reserved for creating slow-motion effects. Recording at such high frame rates allows filmmakers to slow down the footage during playback, revealing intricate details that are not visible at normal speeds. This technique is popular in action sequences, scientific research, and artistic video productions​​. At times, even sports events can be recorded at high FPS, which allows for slowing down the video during action replays.

Which factors influence the choice of frame rate?

As mentioned above, different frame rates are suitable for different use cases. There is no one single "best" frame rate. The selection of frame rate is dependent on the following factors:

• Content Type: The nature of the video content significantly influences the choice of frame rate. For instance, narrative films and TV dramas often use 24fps for a classic, cinematic feel, while live sports broadcasts and video games benefit from the smoother motion provided by 30fps or 60fps​.
• Desired Effect: Different frame rates create different visual effects. Higher frame rates can make video look more lifelike and detailed but may also result in the "soap opera effect," where video appears unnaturally smooth. Lower frame rates can create a more traditional, cinematic look but may struggle with fast motion​.
• Playback and Delivery Medium: The platform and devices on which the video will be viewed also affect frame rate decisions. For example, standard web videos and YouTube content often use 30fps, while films shown in theaters stick to 24fps. Understanding the capabilities and limitations of the playback medium ensures the best viewing experience​​.

What is the impact of frame rate on video size?

Since video frame rate is the number of frames or images in a second, it is naturally implied that a higher frame rate means more image data needs to be stored. Therefore, higher frame rates lead to a larger file size.

The processing requirements also increase at a high frame rate and with a larger file size. While streaming high frame rate content without buffering, one also needs more bandwidth. When storing, editing, and streaming high video frame rate content, these factors should be considered. It is essential to balance the need for quality videos with practical constraints like file size, processing, and streaming capacity.

What is the impact of frame rate on video quality?

A higher frame rate does not change your video's quality. It also does not impact your video resolution, such as 1080p or 4K. All of these are independent factors. While a higher video frame rate does improve the realism in your videos or increase the amount of detail you can capture in the video, it does not change your video's quality.

Wrapping it up

Choosing the correct frame rate for your video based on the video content and the desired visual effect and balancing it with practical considerations like file size and the intended playback medium will help improve the video viewing experience for the audience.

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