A uniquely decodable code is a code where every encoded message sequence has only one valid decomposition into codewords. The video emphasizes that prefix-freeness guarantees this property, but the converse is not required; a code can be uniquely decodable without being prefix-free.
Conditions: Concerns decoding of concatenated codeword sequences at the receiver.; The video does not state a formal symbolic definition beyond the examples and prose.
A uniquely decodable code is a code where every encoded message sequence has only one valid decomposition into codewords. The video emphasizes that prefix-freeness guarantees this property, but the converse is not required; a code can be uniquely decodable without being prefix-free.
Conditions: Concerns decoding of concatenated codeword sequences at the receiver.; The video does not state a formal symbolic definition beyond the examples and prose.
A non-prefix-free code causes ambiguity because a received bit string can be segmented in more than one way into valid codewords. For Code 3, the received string 00 can be parsed as two copies of the codeword 0 (giving x1x1) or as one copy of the codeword 00 (giving x3).
Conditions: Occurs when at least one codeword is a prefix of another codeword.; Illustrated here for concatenated received strings under Code 3.
A non-prefix-free code causes ambiguity because a received bit string can be segmented in more than one way into valid codewords. For Code 3, the received string 00 can be parsed as two copies of the codeword 0 (giving x1x1) or as one copy of the codeword 00 (giving x3).
Conditions: Occurs when at least one codeword is a prefix of another codeword.; Illustrated here for concatenated received strings under Code 3.