SFWRENG 4J03 Lecture Notes - Lecture 4: Huffman Coding, Mathtype, Amplitude Modulation
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Pulse position modulation 4 e. g. 2) 4. Prefix property: any code should be uniquely decipherable. No complete code word can be a prefix at another code word enciphering m1 0 m2 0. Highest probably messages will be given least number of bits and vice versa. Algorithm: arrange the messages according to order of decreasing probability, consider the last 2 messages in the ensemble. Assign a 0 & 1 to those 2 messages: add the probabilities of the last 2 messages, arrange the messages in the order of decreasing probability. Keep the newest calculated probabilities on top if tie: go to step 2 until you only have 2 messages, calculate efficiency e. g. 1) Calculate a huffman code for the following message ensemble with probabilities: 0. 1, 0. 3, 0. 16, Analog: pulse amplitude modulation (pam), pulse width modulation (pwm), pulse position modulation (ppm): Digital: pulse code modulation (pcm), delta modulation (dm), adaptive dm (adm):