Homework 1 is now on Sakai. It is due Friday, July 17.
Network Signal Info
This is an app (there are both free and pro versions) available only for
Android. The developer site is kaibits-software.com.
It provides information on your cellular and LTE network: signal strength,
cell (station/system/network), MNC/MCC, etc. Right now, for example, it
shows my cell as
station ID 34497
system ID 4384
network id 122
My MCC (Mobile Country Code) is 311, and my MNC (Mobile Network Code) is
580. We can look these up at wikipedia.org/wiki/Mobile_country_code
to find this is US Cellular.
All VoIP solutions contend with packet
switched networks that were not designed to transmit real-time media
streams. Packet latency and packet loss are the principal manifestations
of this reality, and the jitter
buffer is their canonical solution.
They then describe an adaptive-jitter-buffer algorithm, where the buffer can
change size. That's a bit of a trick, as that means slowing down or speeding
up the audio. In order to do this at all, one must know that
sometimes voice can be stretched (eg by pausing), or shortened. For voice,
the resultant distortion is generally acceptable; for music, it is likely
not.
Notes:
Sound as data: digitized_sound.html
beginning with Fourier Analysis visualization