Gzip decompresses data by reversing the compression process that was applied during gzip compression. Here’s how it works:
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Read Gzip Header: The decompression process starts by reading the gzip file header, which contains metadata such as the original file size, modification time, and compression method used.
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Huffman Decoding: The compressed data is first processed using Huffman decoding. This step reconstructs the original sequences of data by converting the variable-length codes back into their corresponding symbols based on the Huffman tree that was created during compression.
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LZ77 Decompression: After Huffman decoding, the LZ77 algorithm is applied. It uses the references (offsets and lengths) stored in the compressed data to reconstruct the original data by replacing the references with the actual data sequences.
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Output the Original Data: Finally, the decompressed data is output, which should match the original data before it was compressed.
This process ensures that the data can be perfectly reconstructed, maintaining the integrity of the original information.
