Optimize time image processing

Good day, I have some programs distributed processing cluster that you want to optimize for the processing time of an image x faster and more efficiently, and also that the more worker is agregen better the result of processing and the less increase processing time, could help to optimize this code:

clc;
clear;
sombrero = [0  0  0 -1 -1 -1  0  0  0;...
            0 -2 -3 -3 -3 -3 -3 -2  0;...
            0 -3 -2 -1 -1 -1 -2 -3  0;...
           -1 -3 -1  9  9  9 -1 -3 -1;...
           -1 -3 -1  9 19  9 -1 -3 -1;...
           -1 -3 -1  9  9  9 -1 -3 -1;...
            0 -3 -2 -1 -1 -1 -2 -3  0;...
            0 -2 -3 -3 -3 -3 -3 -2  0;...
            0  0  0 -1 -1 -1  0  0  0];
ruta='/home/alejandro/Documentos/MatLab/ProgramacionDistribuida/Imagen_p_Distribucion/1.jpg';
im=imread(ruta); 
imA=rgb2gray(im);
p1=parpool('JobScheduler',6);
addAttachedFiles(p1,{'Funcion_duplicate_pixel.m','funcion_Aplicacion_mascaras.m'});
tic
spmd
    d1=codistributor1d(2);
    c = codistributed(imA, d1);  
    som=funcion_Aplicacion_mascaras(Funcion_duplicate_pixel(getLocalPart(c),sombrero),sombrero);     
end
sali2=[som{1} som{2} som{3} som{4}];
imshow(sali2);
end
delete(gcp);

well I have two functions applies duplicating one pixel to apply Macara Mexican hat, eye and can help Thank you very much for your attention