MATLAB: Simulink-Coder image data representation in C

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Hello, I have a question related to an image representation out of Matlab Simulink Coder. If I have a Simulink block with an RGB image output size for instance 320x240x3, I get in my generated code an array with the size "img[230400]". My question is now, if I want to write this array to an .ppm-file-format, how do I have to iterate over this array to get a row based rgb order and see the image.

Thanks in advanced.

Best Answer

Assuming img is an I x J x K array, the array element given in MATLAB by:

img(i,j,k)

can accessed in the generated C code at:

img[(k-1)*(J*I) + (j-1)*I + (i-1)];

For a more detailed explanation of how matrices and arrays are stored in generated code, refer to the following documentation:

http://www.mathworks.com/help/coder/ug/code-generation-of-matrices-and-arrays.html

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