how to sparse represent a image?

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lohith
lohith il 27 Dic 2014
Commentato: Snigdha KN il 26 Gen 2017
hi,
i'm trying to create a sparse matrix for an image.
i've given the command as,
a=imread('imagename.format')
b=sparse(a)
i'm getting the output for the first command and for the second command i'm getting a error as mentioned below,
Undefined function 'sparse' for input arguments of type 'uint8'
please help thanks in advance

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Shoaibur Rahman
Shoaibur Rahman il 27 Dic 2014
Convert a to double first, and the use that in sparse. Make sure that a is not in 3D, if so, then make it 2D before using in sparse.
a = double(a);
b = sparse(a); % for 3D a, you may use b = sparse(a(:,:,1)); or 2 or 3 instead of 1 here.
spy(b) % see the sparsity pattern
  4 Commenti
Guillaume
Guillaume il 17 Mar 2016
Modificato: Guillaume il 17 Mar 2016
@Isra, I suggest you start your own question posting the exact code you're using and explaining what 'not working' means exactly (you get an error? if so, which? no error but not the output you want? if so what output do you want? etc.)
Snigdha KN
Snigdha KN il 26 Gen 2017
This code shows an error when executed. It shows undefined function 'sparse' for argument type 'double'

Accedi per commentare.

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