What is bitrate?
In one sentence: How many bits a stream sends each second. A lower bitrate means a video call must use bigger blocks, fewer pictures, or freeze.
A little more
Bitrate is how many bits travel each second in a stream such as a video call, a livestream or a downloaded film. It is usually measured in kilobits or megabits per second (kb/s or Mb/s). A higher bitrate can keep more detail; a lower one must simplify the picture.
Calls adapt: when the path is busy they turn the bitrate down, which you see as bigger blocks, softer backgrounds and sometimes freezes. Upload bitrate is often the tight limit on home connections, which is why you can look blurry to others while their picture still looks fine to you.
See it in action
- BonusWhy does a video call go blurry when the connection is slow?Dial a pretend video call's bandwidth thinner, spend a tiny 10-bit budget on eyes vs mouth vs wallpaper to still read a facial expression, then reveal the clear face.7 min · interactive
- BonusWhy does a video go blurry, then sharp?You press play and the picture is smudgy for a second, then it snaps sharp.8 min · interactive
- BonusWhat happens when you squish a video too much?Squish a real (tiny) picture the way phones squish video: watch thin whiskers crumble first, then 8x8 blocks appear, then a splat.10 min · interactive
Do it for real
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