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@MichaelTr7
Last active December 8, 2022 23:33
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MATLAB script that splits an image into blocks/tiles.
clf;
Image = imread("peppers.png");
[Image_Height,Image_Width,Number_Of_Colour_Channels] = size(Image);
Block_Size = 50;
Number_Of_Blocks_Vertically = ceil(Image_Height/Block_Size);
Number_Of_Blocks_Horizontally = ceil(Image_Width/Block_Size);
Image_Blocks = struct('Blocks',[]);
Index = 1;
for Row = 1: +Block_Size: Number_Of_Blocks_Vertically*Block_Size
for Column = 1: +Block_Size: Number_Of_Blocks_Horizontally*Block_Size
Row_End = Row + Block_Size - 1;
Column_End = Column + Block_Size - 1;
if Row_End > Image_Height
Row_End = Image_Height;
end
if Column_End > Image_Width
Column_End = Image_Width;
end
Temporary_Tile = Image(Row:Row_End,Column:Column_End,:);
%Storing blocks/tiles in structure for later use%
Image_Blocks(Index).Blocks = Temporary_Tile;
subplot(Number_Of_Blocks_Vertically,Number_Of_Blocks_Horizontally,Index); imshow(Temporary_Tile);
Index = Index + 1;
end
end
%***************************************************%
%Uncomment to save the images to seperate .jpg files%
%***************************************************%
% for Block_Index = 1: length(Image_Blocks)
% imwrite(Image_Blocks(Block_Index).Blocks,"Block" + num2str(Block_Index) + ".jpg");
% end
clf;
Image = imread("peppers.png");
[Image_Height,Image_Width,Number_Of_Colour_Channels] = size(Image);
Block_Size = 50;
Number_Of_Blocks_Vertically = ceil(Image_Height/Block_Size);
Number_Of_Blocks_Horizontally = ceil(Image_Width/Block_Size);
Image_Blocks = struct('Blocks',[]);
Index = 1;
for Row = 1: +Block_Size: Number_Of_Blocks_Vertically*Block_Size
for Column = 1: +Block_Size: Number_Of_Blocks_Horizontally*Block_Size
Row_End = Row + Block_Size - 1;
Column_End = Column + Block_Size - 1;
if Row_End > Image_Height
Row_End = Image_Height;
end
if Column_End > Image_Width
Column_End = Image_Width;
end
Temporary_Tile = Image(Row:Row_End,Column:Column_End,:);
%Storing blocks/tiles in structure for later use%
Image_Blocks(Index).Blocks = Temporary_Tile;
% subplot(Number_Of_Blocks_Vertically,Number_Of_Blocks_Horizontally,Index); imshow(Temporary_Tile);
Index = Index + 1;
end
end
%*************************************************************************%
%MODIFYING THE BLOCKS%
%*************************************************************************%
for Block_Index = 1: length(Image_Blocks)
if(mod(Block_Index,2) == 0)
%Darkening every other block%
Image_Blocks(Block_Index).Blocks = 0.5.*(Image_Blocks(Block_Index).Blocks);
end
end
%*************************************************************************%
%RECONSTRUCTING THE IMAGE%
%*************************************************************************%
Reconstructed_Image = zeros(size(Image));
Block_Index = 1;
for Row = 1: +Block_Size: Image_Height
for Column = 1: +Block_Size: Image_Width
Height_Of_Block = size(Image_Blocks(Block_Index).Blocks,1);
Width_Of_Block = size(Image_Blocks(Block_Index).Blocks,2);
Reconstructed_Image(Row:Row+Height_Of_Block-1,Column:Column+Width_Of_Block-1,:) = Image_Blocks(Block_Index).Blocks;
Block_Index = Block_Index + 1;
end
end
imshow(uint8(Reconstructed_Image));
clf;
Image = imread("peppers.png");
[Image_Height,Image_Width,Number_Of_Colour_Channels] = size(Image);
Block_Size = 50;
Number_Of_Blocks_Vertically = floor(Image_Height/Block_Size);
Number_Of_Blocks_Horizontally = floor(Image_Width/Block_Size);
Image_Blocks = struct('Blocks',[]);
Index = 1;
for Row = 1: +Block_Size: Number_Of_Blocks_Vertically*Block_Size
for Column = 1: +Block_Size: Number_Of_Blocks_Horizontally*Block_Size
Row_End = Row + Block_Size - 1;
Column_End = Column + Block_Size - 1;
if Row_End > Image_Height
Row_End = Image_Height;
end
if Column_End > Image_Width
Column_End = Image_Width;
end
Temporary_Tile = Image(Row:Row_End,Column:Column_End,:);
%Storing blocks/tiles in structure for later use%
Image_Blocks(Index).Blocks = Temporary_Tile;
subplot(Number_Of_Blocks_Vertically,Number_Of_Blocks_Horizontally,Index); imshow(Temporary_Tile);
Index = Index + 1;
end
end
%***************************************************%
%Uncomment to save the images to seperate .jpg files%
%***************************************************%
% for Block_Index = 1: length(Image_Blocks)
% imwrite(Image_Blocks(Block_Index).Blocks,"Block" + num2str(Block_Index) + ".jpg");
% end
%Getting all the images in the directory%
Folder_Directory = "";
File_Type = "png";
Images = dir(fullfile(Folder_Directory,"*." + File_Type));
for Image_Index = 1: length(Images)
Image_Name = Images(Image_Index).name;
Image = imread(fullfile(Folder_Directory,Image_Name));
File_Prefix = strsplit(Image_Name,".");
File_Prefix = File_Prefix{1};
[Image_Height,Image_Width,Number_Of_Colour_Channels] = size(Image);
Block_Size = 100;
Number_Of_Blocks_Vertically = floor(Image_Height/Block_Size);
Number_Of_Blocks_Horizontally = floor(Image_Width/Block_Size);
Image_Blocks = struct('Blocks',[]);
Index = 1;
for Row = 1: +Block_Size: Number_Of_Blocks_Vertically*Block_Size
for Column = 1: +Block_Size: Number_Of_Blocks_Horizontally*Block_Size
Row_End = Row + Block_Size - 1;
Column_End = Column + Block_Size - 1;
if Row_End > Image_Height
Row_End = Image_Height;
end
if Column_End > Image_Width
Column_End = Image_Width;
end
Temporary_Tile = Image(Row:Row_End,Column:Column_End,:);
%Storing blocks/tiles in structure for later use%
Image_Blocks(Index).Blocks = Temporary_Tile;
% subplot(Number_Of_Blocks_Vertically,Number_Of_Blocks_Horizontally,Index); imshow(Temporary_Tile);
Index = Index + 1;
end
end
mkdir(File_Prefix + "_Blocked/");
for Block_Index = 1: length(Image_Blocks)
imwrite(Image_Blocks(Block_Index).Blocks,fullfile(File_Prefix + "_Blocked/",File_Prefix + "_" + num2str(Block_Index) + ".jpg"));
end
end
@MichaelTr7
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MichaelTr7 commented Dec 14, 2021

@febbyftrp I believe that the path must be added since this is an absolute path that MATLAB does not have access to. Relative paths in the MATLAB Current Folder side panel do not have to be added. To add your folder the following code can be added to the top of your script:

Folder_Directory = '/Users/febbyfitri/Documents/MATLAB/febby/AVI(Uncompressed)_subtraction';
addpath(Folder_Directory);

@febbyftrp
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I have already tried it sir, but still can't work. Does the version of Matlab affect sir? btw, I use Matlab 2018a @MichaelTr7

@MichaelTr7
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MichaelTr7 commented Dec 27, 2021

@febbyftrp I don’t believe the version of MATLAB should have any effect on this. Is it possible to just load an image from that directory/folder using the imread() function?

@MichaelTr7
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MichaelTr7 commented Feb 27, 2022

Use the Split_Image_And_Reconstruct.m to modify and reconstruct the image blocks.

Screen Shot 2022-02-27 at 5 56 47 PM

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