Question

Consider the following codes:
A. Hamming Code,
B. Huffman Code,
C. Shannon-Fano Code,
D. Convolution Code. Which of these are source codes?

• A. A, B and D only
• B. B and C only
• C. A and D only
• D. B, C and D only

Hint:

If the purpose of the code is to make the file smaller (compression), it's a source code. If its purpose is to make the transmission more robust against errors, it's a channel code.

Answer 1

The Correct Option is B

Step 1: Distinguish Source and Channel Coding.

• Source Coding (Data Compression): Aims to efficiently represent source data by removing redundancy, thereby reducing the number of bits required. Examples include Huffman and Shannon-Fano coding.
• Channel Coding (Error Control Coding): Aims to protect data from errors during transmission by adding controlled redundancy. Examples include Hamming, convolutional, and block codes.

Step 2: Categorize the Provided Codes.

• (A) Hamming Code: A block code designed for error detection and correction. Classified as a channel code.
• (B) Huffman Code: A variable-length algorithm for lossless data compression. Classified as a source code.
• (C) Shannon-Fano Code: Another variable-length technique used for data compression. Classified as a source code.
• (D) Convolutional Code: An error-correcting code that uses Boolean polynomial functions to generate parity symbols for a data stream. Classified as a channel code.

Step 3: Determine the Source Codes.

The identified source codes are:

• Huffman Code (B)
• Shannon-Fano Code (C)