用matlab编写游程编码解码函数

游程编码是一种数据压缩技术，常用于图像处理和信号分析中。在MATLAB中，你可以通过以下步骤创建一个简单的游程编码和解码函数：

首先，你需要理解游程编码的基本原理：将连续的一维像素序列转换成一个包含行和列索引的编码。这里是一个简单的游程编码函数示例：

function encoded = encode_rle(image)
% Encode image using Run-Length Encoding (RLE)
[row, col] = size(image);
encoded = zeros(row * col, 2); % Initialize the output vector
current_pixel = image(1, 1); % Start with first pixel

for i = 1:row
    for j = 1:col
        if image(i, j) ~= current_pixel
            encoded(end+1:end+(j-1), :) = [i-1, j-1]; % Store previous run
            current_pixel = image(i, j); % Update current pixel
        end
    end
end

% Add last run after the loop
if ~isempty(encoded)
    encoded(end+1,:) = [row-1, col-1];
end
end

function decoded = decode_rle(encoded, original_image)
% Decode RLE-encoded data back to an image
[row, ~] = size(original_image);
decoded = zeros(row, col);

current_run = [];
previous_row = 0;
previous_col = 0;

for i = 1:size(encoded, 1)
    row_index = encoded(i, 1);
    col_index = encoded(i, 2);
    
    % Check for new run
    if row_index > previous_row || col_index > previous_col
        decoded([previous_row+1 : row_index], [previous_col+1 : col_index]) = current_run(end+1,:);
    end
    
    % Update current run and position
    current_run = [current_run; ones(col_index-col_previous, 1)];
    previous_row = row_index + 1;
    previous_col = col_index + 1;
end

% Assign last run, if any
decoded(previous_row+1:end, previous_col+1:end) = current_run;
end

这两个函数分别实现了游程编码（encode_rle）和解码（decode_rle）。