Best way for a 3d matrix

Tricky, I really appreciate your help.

Here's the code. It's just a small test I'm doing to find the best way to do what I need.

All this is suposed to do is send the input(entrada) to the output(saida).

---------PACKAGE---------

LIBRARY ieee;

USE ieee.std_logic_1164.all;

PACKAGE matrizes IS

TYPE array_entrada IS ARRAY (0 TO 3, 0 TO 3, 0 TO 3) OF STD_LOGIC;

TYPE array_saida IS ARRAY (0 TO 3, 0 TO 3, 0 TO 3) OF STD_LOGIC;

END matrizes;

----------------------

-- MAIN CODE

----------------------

LIBRARY ieee;

USE ieee.std_logic_1164.all;

USE work.matrizes.all;

ENTITY rct IS

PORT (

clk: IN STD_LOGIC;

entrada: IN array_entrada;

saida: OUT array_saida);

END rct;

ARCHITECTURE comportamento OF rct IS

TYPE array1 IS ARRAY (0 TO 3, 0 TO 3, 0 TO 3) OF STD_LOGIC;

SIGNAL sinal_entrada: array1;

Begin

PROCESS(CLK)

BEgin

FOR i IN 0 TO 3 LOOP

FOR ii IN 0 TO 3 LOOP

FOR iii IN 0 TO 3 LOOP

sinal_entrada(i,ii, iii)<= entrada(i,ii, iii);

saida(i,ii, iii)<=sinal_entrada(i,ii, iii);

END LOOP;

END LOOP;

END LOOP;

END PRocess;

END comportamento;

The numbers represents pixels of an image.

I want to work with an 8x8 image, each pixel with 8 bits.

Maybe there's some easiest way to do that. This is just what I could think about.

As reference I'm using the book Circuit Design with VHDL - Pedroni.

Thank You!