ELI5 Whatsapp video calls


ELI5 So when me and my friend video call each other then when we play music through our phone speakers then we can still hear each others voices but not the music

In: Technology

Most phones and devices that can carry sound have what is called “echo cancellation”. Oversimplified the phone knows what sounds are being played trough the speaker, and can then try to ignore those sounds when the microphone picks them up.

Audio is just waves, and you can cancel one wave with it’s inverse wave. Phones will play the inverse sound in to the microphone when the speaker plays it, so that the “bad” sound cancels out while all other sounds is undisturbed.