close all

img = imread('lena.tif');

img_bitstream = '11111111111111100000000000000000001111'

input = str2num(img_bitstream')';

max_rep = find_max_consecutive_repetition(input);

bit_len = ceil(log2(max_rep));

rle = rle_encode_bitstream(input,bit_len);

compression_ratio = size(input)/size(rle)

function max_rep = find_max_consecutive_repetition(bitstream)

maxCount = 0;

currentCount = 0;

previousBit = NaN; % initialize with NaN to handle the case where the bitstream starts with a NaN value

for i = 1:length(bitstream)

bit = bitstream(i);

if bit == previousBit

currentCount = currentCount + 1;

else

maxCount = max([maxCount, currentCount]);

currentCount = 1;

previousBit = bit;

end

end

max_rep = max([maxCount, currentCount]);

function rle = rle_encode_bitstream(bitstream,bit_len)

% Initialize variables

rle = [];

current = bitstream(1);

count = 1;

% Loop through the bitstream

for i = 2:length(bitstream)

if bitstream(i) == current

% If the current bit is the same as the previous one, increment count

count = count + 1;

else

% If the current bit is different, add the previous bit and its count to the output

rle = [rle dec2bin(count,bit_len) num2str(current)];

current = bitstream(i);

count = 1;

end

end

% Add the last bit and its count to the output

rle = [rle dec2bin(count,bit_len)];

rle = [rle num2str(current)];