MULTIMEDIA AND QUALITY OF SERVICE
COMPRESSION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Run-length encoding
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Dictionary encoding
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Variable-length encoding
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None of the above
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Detailed explanation-1: -Larger dictionary frequently improves compression of big files, especially in solid mode, but it also leads to slower compression and higher memory requirements. Normally we recommend to use 4 MB dictionary for RAR format and 32 MB for RAR5 (RAR 5.0) archive format. You can read more about the dictionary size here.
Detailed explanation-2: -The maximum value for dictionary size is 1536 MB, but 32-bit version of 7-Zip allows to specify up to 128 MB dictionary.
Detailed explanation-3: -Dictionary-based compression algorithms work by parsing the input into a sequence of substrings (also called words) T 1, T 2, …, T d and by encoding a compact representation of these substrings. The parsing is usually done incrementally and on-line with the following iterative procedure.