Some questions about H.26x, VP9, AV1 ?

[rockerovo]

why we use AVC and HEVC on phones and it is not free why we don't use VP9 or av1?

why tv broadcasting use h.26x not vp9 or av1?

what's the difference between software and hardware decoding?

[Selur]

why we use AVC and HEVC on phones and it is not free why we don't use VP9 or av1?

Both VP9 and AV1 take require faster CPUs. Also their hardware decoder support is less wide spread.
Also AV1 is rather new and VP9 is rather crappy (from my experience).

why tv broadcasting use h.26x not vp9 or av1?

because H.26X:
a. is older (thus hardware is cheaper an probably already been bought and need to be amortized)
b. is longer standardized for broadcast (not sure there even is a standard for broadcasting VP9 or AV1)
c. requires less processing power for en- and decoding
d. have better/cheaper and thus more wide spread hardware encoding support
e. have better/cheaper and thus more wide spreadhardware decoding support (and are thus present on more consumer devices); doesn't make much sense to switch to a broadcasting method that can't reach a wide audience.

what's the difference between software and hardware decoding?

the obvious: one is done through the CPU, the other through the VPU (a dedicated decoder chip for video processing)
Smartphones for example have usually not that powerful CPUs but rather powerful VPUs.
(CPUs are usually way more expensive since they are way more flexible in what they can do.)

Cu Selur