Index in position 2 exceeds array bounds. (reason for error)
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img=imread('D:/lena1.png');
[height, width]=size(img);
for a=1:8:height
disp(height);
for b=1:8:width
imgdct_8(a:a+7,b:b+7)=dct2(img(a:a+7,b:b+7));
end
end
for i=1:8
for j=1:8
qtz_mtrx(i,j)=1+((i+j)* 15);
end
end
回答（1 个）
Walter Roberson
2022-4-15
[height, width]=size(img);
You are probably thinking that code is the same as
temp = size(img) ;
height = temp(1);
width = temp(2);
But it is not the same. Instead it means
temp = size(img);
height = temp(1);
width = prod(temp(2:end));
This matters because lena1.png is a color image, so your width ends up being 3 times what you expect.
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2022-4-15
2022-4-15
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