【将文本编码为图像灰度级别】以 ASCII 编码并与灰度级别位混合将文本字符串隐藏到图像像素的最低位中，使其不明显研究（Matlab代码实现）

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本文目录如下：

目录

1 概述

2 运行结果

3 参考文献

4 Matlab代码实现

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1 概述

经过文本编码技术的应用，我们可以将文本字符串隐藏在图像像素的最低位中，使其在视觉上不易察觉。

在这个实例中，用户可以输入文本消息，并选择要隐藏消息的图像（这些图像是来自MATLAB附带的演示图像列表）。用户还可以选择要用于编码消息的位平面。首先，将文本消息转换为ASCII代码，然后将其转换为二进制字符串。接着，将被选择的位平面与图像像素相对应，从左上角像素开始，自上而下，自左至右进行分配。

由于文本消息以ASCII编码并与灰度级别位混合，所以在图像上并不容易被察觉到。这样的隐藏技术在隐写术领域中具有重要意义，允许用户在图像中嵌入机密信息，而外观上几乎没有变化。

通过这种方法，可以实现图像与文本之间的隐蔽通信，为信息安全和隐私保护提供了一种隐蔽的手段。然而，需要注意的是，隐写术的应用必须遵循法律和伦理准则，以确保信息的嵌入和提取仅在合法的领域进行。

2 运行结果

部分代码：

if numberOfColorChannels > 1
	% It's not really gray scale like we expected - it's color.
	% Convert it to gray scale by taking only the green channel.
	grayCoverImage = grayCoverImage(:, :, 2); % Take green channel.
elseif ~isempty(storedColorMap)
	% There's a colormap, so it's an indexed image, not a grayscale image.
	% Apply the color map to turn it into an RGB image.
	grayCoverImage = ind2rgb(grayCoverImage, storedColorMap);
	% Now turn it into a gray scale image.
	grayCoverImage = uint8(255 * mat2gray(rgb2gray(grayCoverImage)));
end
[rows, columns, numberOfColorChannels] = size(grayCoverImage); % Update.  Only would possibly change, and that's if the original image was RGB or indexed.
% Display the image.
hFig = figure;
subplot(1, 2, 1);
imshow(grayCoverImage, []);
axis on;
caption = sprintf('The Original Grayscale Image\nThe "Cover" Image.');
title(caption, 'FontSize', fontSize, 'Interpreter', 'None');

% Set up figure properties:
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Get rid of tool bar and pulldown menus that are along top of figure.
set(gcf, 'Toolbar', 'none', 'Menu', 'none');
% Give a name to the title bar.
set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off') 

%===============================================================================
% Get the string the user wants to hide:
hiddenString = 'This is your sample hidden string.';
% Ask user for a string.
defaultValue = hiddenString;
titleBar = 'Enter the string you want to hide';
userPrompt = 'Enter the string you want to hide';
caUserInput = inputdlg(userPrompt, titleBar, [1, length(userPrompt) + 75], {num2str(defaultValue)});
if isempty(caUserInput)
	% Bail out if they clicked Cancel.

if numberOfColorChannels > 1
    % It's not really gray scale like we expected - it's color.
    % Convert it to gray scale by taking only the green channel.
    grayCoverImage = grayCoverImage(:, :, 2); % Take green channel.
elseif ~isempty(storedColorMap)
    % There's a colormap, so it's an indexed image, not a grayscale image.
    % Apply the color map to turn it into an RGB image.
    grayCoverImage = ind2rgb(grayCoverImage, storedColorMap);
    % Now turn it into a gray scale image.
    grayCoverImage = uint8(255 * mat2gray(rgb2gray(grayCoverImage)));
end
[rows, columns, numberOfColorChannels] = size(grayCoverImage); % Update.  Only would possibly change, and that's if the original image was RGB or indexed.
% Display the image.
hFig = figure;
subplot(1, 2, 1);
imshow(grayCoverImage, []);
axis on;
caption = sprintf('The Original Grayscale Image\nThe "Cover" Image.');
title(caption, 'FontSize', fontSize, 'Interpreter', 'None');

% Set up figure properties:
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Get rid of tool bar and pulldown menus that are along top of figure.
set(gcf, 'Toolbar', 'none', 'Menu', 'none');
% Give a name to the title bar.
set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off') 

%===============================================================================
% Get the string the user wants to hide:
hiddenString = 'This is your sample hidden string.';
% Ask user for a string.
defaultValue = hiddenString;
titleBar = 'Enter the string you want to hide';
userPrompt = 'Enter the string you want to hide';
caUserInput = inputdlg(userPrompt, titleBar, [1, length(userPrompt) + 75], {num2str(defaultValue)});
if isempty(caUserInput)
    % Bail out if they clicked Cancel.

3 参考文献

文章中一些内容引自网络，会注明出处或引用为参考文献，难免有未尽之处，如有不妥，请随时联系删除。

[1]张健.复杂图像文本提取关键技术与应用研究[D].南开大学,2015.

[2]张姁.基于小波的彩色图像灰度水印算法研究[D].河北工业大学[2023-09-25].DOI:10.7666/d.d049536.

[3]刘勇.二值图像压缩编码算法的若干研究[D].山东大学,2009.DOI:10.7666/d.y1562519.

4 Matlab代码实现