Uncompressed video requires an extremely high data rate and is impractical for consumer use in cellphones, cameras, drones, or anything else. To address this issue, algorithms called "Codecs" have been developed to compress video into manageable file sizes.
The creation of the H.264 (AVC) codec in 2003 revolutionized the consumer marketplace and led to a dramatic increase in smaller handheld devices capable of taking higher quality video. As of 2019, an estimated 91% of video is compressed using H.264.
Since 2003, video has continued to increase in resolution and detail as cameras became smaller and more capable; However, that increase in quality also means an increase in file size. To improve compression even further, additional codecs such as H.265 (HEVC), AV1, and H.266 (VVC) have been developed and are competing for market share.
The streaming service WOWZA does an excellent job of explaining the Codec landscape in more detail.
https://www.youtube.com/watch?v=vLIznXy27Pc
https://www.youtube.com/watch?v=r6Rp-uo6HmI
Choosing the correct bitrate can be difficult at first. Several handy bitrate charts published by Youtube and WOWZA exist to help those just starting out in livestreaming on what to choose.
<aside> 💡 These charts identify optimum bitrates if conditions were perfect. This does not necessarily apply when streaming from the field on shaky LTE networks that CAP teams may find themselves in.
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