A few words about audio compression ▣Analog signal sampled▣Example:8,000 at constant rate samples/sec,256 o telephone:8,000 quantized values-> samples/sec 64,000bps CD music:44,100 ▣Receiver converts it samples/sec back to analog signal: Each sample quantized, o some quality reduction i.e.,rounded oe.g.,28=256 possible Example rates quantized values ▣CD:1.411Mbps ▣Each quantized value □MP3:96,128,160kbps represented by bits Internet telephony: o8 bits for 256 values 5.3-13kbps 7:Multimedia Networking 7-137: Multimedia Networking 7-13 A few words about audio compression  Analog signal sampled at constant rate  telephone: 8,000 samples/sec  CD music: 44,100 samples/sec  Each sample quantized, i.e., rounded  e.g., 28=256 possible quantized values  Each quantized value represented by bits  8 bits for 256 values  Example: 8,000 samples/sec, 256 quantized values -> 64,000 bps  Receiver converts it back to analog signal:  some quality reduction Example rates  CD: 1.411 Mbps  MP3: 96, 128, 160 kbps  Internet telephony: 5.3 - 13 kbps