save as GeoTIFF post-processed matrix

I have been working with Matlab on statistical analysis of a Landsat image, which after reading with [A R] = geotiffread(), I continue processing the matrix A, the final product is of totally different size of the original matrix A, I have read with [A R] = geotiffread(). Now I want to go back to a georefreneced image to plot it georefrenced with shapefiles, but the size of the newly processed materix is totally different…

originally, It is the same image but the size of the new matrix is totally different after post-processing:

Original Image :

>> size(green_20170731Rescaled_Band_nan)

ans =

6616 6763

Current Image:

>> size(ProcessedStatsIamge)

ans =

103 105

How can I save this new post-processed matrix as GeoTIFF image file and have coordinate system as well as conserving same spatial resolution per pixel of 30m to be able to plot Shapefiles boundaries of cities and counties as the original Landsat image enabled me?