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huffmandict

PURPOSE ^

%

SYNOPSIS ^

function cw_list=huffmandict(sym,source_prob,togglecode,minvar)

DESCRIPTION ^

% -*- texinfo -*-
% @deftypefn {Function File} {}  huffmandict (@var{symb}, @var{prob})
% @deftypefnx {Function File} {}  huffmandict (@var{symb}, @var{prob}, @var{toggle})
% @deftypefnx {Function File} {}  huffmandict (@var{symb}, @var{prob}, @var{toggle}, @var{minvar})
%
% Builds a Huffman code, given a probability list. The Huffman codes 
% per symbol are output as a list of strings-per-source symbol. A zero 
% probability symbol is NOT assigned any codeword as this symbol doesn't 
% occur in practice anyway.
%
% @var{toggle} is an optional argument with values 1 or 0, that starts 
% building a code based on 1's or 0's, defaulting to 0. Also @var{minvar} 
% is a boolean value that is useful in choosing if you want to optimize 
% buffer for transmission in the applications of Huffman coding, however 
% it doesn't affect the type or average codeword length of the generated 
% code. An example of the use of @code{huffmandict} is
%
% @example
% @group
%   huffmandict(symbols, [0.5 0.25 0.15 0.1]) => CW(0,10,111,110)
%   huffmandict(symbols, 0.25*ones(1,4)) => CW(11,10,01,00)
%
%   prob=[0.5 0 0.25 0.15 0.1]
%   dict=huffmandict(1:5,[0.5 0 0.25 0.15 0.1],1)
%   entropy(prob)
%   laverage(dict,prob)
%         
%   x =   [0.20000   0.40000   0.20000   0.10000   0.10000];
%   %illustrates the minimum variance thing.
%   huffmandict(1,x,0,true) %min variance tree.
%   huffmandict(1,x)     %normal huffman tree.
% @end group
% @end example
%
% Reference: Dr.Rao's course EE5351 Digital Video Coding, at UT-Arlington.
% @end deftypefn
% @seealso{huffmandeco, huffmanenco}

CROSS-REFERENCE INFORMATION ^

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