Video resolutions are a measure of how many pixels a video frame contains. Higher video resolutions generally offer a clearer picture, but also increase the file size. Resolutions are referred to using the total number of horizontal and vertical pixels in a single frame.
Pixels or picture elements are the smallest digital graphical units that monitors or screens can display. Videos also have a color depth, which is the range of colors available for a single pixel. Color depths, measured in bits, are often between 24 and 36 bits per pixel.
Besides the pixels and color depth, frame rate can significantly impact quality. The frame rate of a video file is the number of individual images displayed in a second. Most videos are at least 24 frames per second (FPS), with the standard being 30 FPS. Sports and livestreams with a lot of motion may require 60 FPS to appear smooth.
The most common video resolutions are the following:
- 360p is the lowest quality resolution commonly used for smartphones.
- 480p or standard definition is a resolution of 720×480.
- 720p or standard high definition is a resolution of 1280×720.
- 1080p or full high definition is a resolution of 1920×1080.
- 4K or ultra high definition is a resolution of 3840×2160.
With broadcasting, there are two common types of scanning methods: progressive and interlaced. The resolutions listed previously with a “p” are progressive, meaning that the lines of each frame are displayed one after the other. Interlaced scanning doubles the perceived frame rate of a video by displaying alternating sets of lines.
A video’s bitrate—a measure of the amount of data within a single second of video—is largely determined by its resolution, frame rate, and bits per pixels. As mentioned before, bits per pixel or color depth is the amount of data for a single pixel. There is usually a higher average bits per pixel for video content with a lot of motion.
With most broadcasters having upload bandwidth constraints, there are limits to the bitrates they can stream at as well. That’s why video compressors, which reduce the file size and bitrate of videos, are crucial for livestreaming. Newer codecs like H.264 and H.265 can efficiently reduce the bitrate of video files without impacting their perceived quality.
It’s important that broadcasters consider the bitrates they want to stream at before they decide on a resolution for recording video content. That’s because higher resolutions can be scaled down using cloud transcoding, but there’s no gain in quality trying to scale up a low-resolution file. Most broadcasters, therefore, choose 1080p 30 FPS for livestreaming, which usually requires a bitrate between 3000-6000 kbps.
Resi’s Web Player makes it easy for broadcasters to set up live and on-demand streams that are high quality and resilient. In fact, Resi’s social streaming solution enables 1080p simulcasting to YouTube and Facebook without any additional bandwidth at the broadcast site. With Resi’s streaming technologies, broadcasters can achieve the highest quality stream possible without worrying about interruptions from network outages.
