@hamje32 - I know that there are a lot of algorithms out there to compress speech. While I can appreciate that the manner of compression is similar to other forms of compression like video compression, I think that speech compression is easier.
Simply, audio doesn’t take up as much space as video. I realize that for Internet phone calls you still need to compress it, but still, even with dial up connections that offered limited bandwidth I was able to make VOIP calls. I could not, by contrast, easily stream video until I got broadband Internet.