finding specific value stored in cell

i have an image[200x200]. i have converted it to cell using mat2cell command which is mat2cell([50 50 50 50],[50 50 50 50],3]}. My original image had a maximum value of pixel on 120,134 i-e 120 row and 130 column. I want to find which cell has got this pixel value in it i-e whether c{5},c{6} etc has got 120,134 value in it..please help me

[Jan]

Please edit the question to explain the type and size of your data exactly: I cannot imagine what "mat2cell([50 50 50 50],[50 50 50 50],3]}" could be.

Are you looking for a certain value or for a specific value or a coordinate?

[David Young]

Jan - mat2cell splits up the original array into subarrays, and the partitioning is specified by the arguments. Here, the image is split up into 16 blocks of 50x50 pixels each. I think sabeeh is asking which block a particular pixel finds itself inside - but the documentation has a diagram which is clearer than any answer I can write would be.

[Jan]

@David: ",3]}" is the part, which confuses me. Most likely "I have an image[200x200]" means "[200 x 200 x 3]".

Answer 1

[Jan]

If you have a cell, which contains numeric arrays (or scalars) and want to find the cell- and array-index of the min and max values, FEX: MinMaxElem works efficiently:

C = num2cell(rand(10, 10, 10), [1, 2]);
[minVal, maxVal, minIdx, maxIdx, minArg, maxArg] = MinMaxElem(C{:});

Now minArg is the linear index (see IND2SUB) of the cell, which contains the minimal element, and minInd is the linear index related to C{minArg}.

Answer 2

[David Young]

I assume your image dimensions are actually 200 x 200 x 3, and also that the call to mat2cell had the image as the first argument, followed by the arguments you show.

In this case, the pixel at (120, 134) in the original image will be in the array stored in c{3,3}, where c is the cell matrix (in fact, at row 20, column 34 of this array).

The documentation for mat2cell explains better than I can which pixel from the original image ends up in which cell.