static private uint byte_grid_to_pixel_hash(ByteGrid grid)
{
if (grid == null ||
!grid.valid_grid)
{
throw new ArgumentNullException("ASCII_Converter: Null ByteGrid object passed when trying to hash the pixel value.");
}
uint hash = 0;
// 2 bits per byte
for (int i = 0; i < grid.height; i++)
{
for (int j = 0; j < grid.width; j++)
{
hash = hash << 2;
GREYSCALE_CONVERSION_VALUES conv_val =
(GREYSCALE_CONVERSION_VALUES)grid.grid[i][j];
if (conv_val <= GREYSCALE_CONVERSION_VALUES.PURE_BLACK)
{
hash += 3;
}
else if (conv_val <= GREYSCALE_CONVERSION_VALUES.SEMI_BLACK)
{
hash += 2;
}
else if (conv_val <= GREYSCALE_CONVERSION_VALUES.GREY)
{
hash += 1;
}
else if (conv_val <= GREYSCALE_CONVERSION_VALUES.WHITE)
{
hash += 0;
}
else
{
throw new InvalidOperationException("ASCII_Converter: Invalid greyscale byte passed.");
}
}
}
return(hash);
}
private static uint[][] hash_byte_grid(ByteGrid[][] byte_grid)
{
if (byte_grid == null
|| (byte_grid.Length > 0
&& byte_grid[0] == null))
{
throw new ArgumentNullException("ASCII_Converter: Unable to create hash.");
}
// takes an n by n array of greyscale pixels
// and converts them to a hash
uint[][] hash_grid = new uint[byte_grid.Length][];
for (int i = 0; i < byte_grid.Length; i++)
{
hash_grid[i] = new uint[byte_grid[i].Length];
for (int j = 0; j < byte_grid[0].Length; j++)
{
hash_grid[i][j] = byte_grid_to_pixel_hash(byte_grid[i][j]);
}
}
return hash_grid;
}
private static ByteGrid[][] create_byte_grid_grid(byte[][] greyscale_bytes, out int remaining_height, out int remaining_width)
{
//if (!is_rectangular_2D_array(greyscale_bytes, 5, 5))
//{
// remaining_height = 0;
// remaining_width = 0;
// return null;
//}
int data_height = greyscale_bytes.Length;
int data_width = greyscale_bytes[0].Length;
int hash_height = calculate_hash_height();
int hash_width = calculate_hash_width();
int result_height = data_height / hash_height;
int result_width = data_width / hash_width;
remaining_height = data_height % hash_height;
remaining_width = data_width % hash_width;
// account for indivisible picture dimensions
if (remaining_height > 0)
{
result_height++;
}
if (remaining_width > 0)
{
result_width++;
}
// get the bytegrids
List<ByteGrid> grid_list = new List<ByteGrid>();
for(int grid_height_index = 0; grid_height_index < result_height; grid_height_index++){
for(int grid_width_index = 0; grid_width_index < result_width; grid_width_index++){
// in the correct grid area of the 2D byte array,
// now copy the appropriate bytes over to the
// temp byte[][], make a ByteGrid out of them, and
// push it into the list
// get the starting, top-left corner of the 2-D byte array you're going to convert to a ByteGrid
int byte_height_index = grid_height_index * hash_height;
byte[][] grid_arr = new byte[hash_height][];
for(int i = 0; i < hash_height; i++){
grid_arr[i] = new byte[hash_width];
int byte_width_index = grid_width_index * hash_width;
for(int j = 0; j < hash_width; j++){
if (byte_height_index >= greyscale_bytes.Length)
{
grid_arr[i][j] = 255; // make the unexisting bit white
}
else if (byte_width_index >= greyscale_bytes[byte_height_index].Length)
{
grid_arr[i][j] = 255; // make the unexisting bit white
}
else
{
grid_arr[i][j] = greyscale_bytes[byte_height_index][byte_width_index];
}
++byte_width_index;
}
byte_height_index++;
}
grid_list.Add(new ByteGrid(grid_arr));
}
}
// push the bytegrids into the result array and return it.
// prepare the return list
ByteGrid[][] result = new ByteGrid[result_height][];
for (int i = 0; i < result_height; i++)
{
result[i] = new ByteGrid[result_width];
}
int result_height_index = 0;
int result_width_index = 0;
foreach (ByteGrid grid in grid_list)
{
result[result_height_index][result_width_index] = grid;
++result_width_index;
if (result_width_index % result_width == 0)
{
++result_height_index;
result_width_index = 0;
}
}
return result;
}
private static uint byte_grid_to_pixel_hash(ByteGrid grid)
{
if(grid == null
|| !grid.valid_grid){
throw new ArgumentNullException("ASCII_Converter: Null ByteGrid object passed when trying to hash the pixel value.");
}
uint hash = 0;
// 2 bits per byte
for(int i = 0; i < grid.height; i++){
for(int j = 0; j < grid.width; j++){
hash = hash << 2;
GREYSCALE_CONVERSION_VALUES conv_val =
(GREYSCALE_CONVERSION_VALUES)grid.grid[i][j];
if (conv_val <= GREYSCALE_CONVERSION_VALUES.PURE_BLACK)
{
hash += 3;
}
else if (conv_val <= GREYSCALE_CONVERSION_VALUES.SEMI_BLACK)
{
hash += 2;
}
else if (conv_val <= GREYSCALE_CONVERSION_VALUES.GREY)
{
hash += 1;
}
else if (conv_val <= GREYSCALE_CONVERSION_VALUES.WHITE)
{
hash += 0;
}
else
{
throw new InvalidOperationException("ASCII_Converter: Invalid greyscale byte passed.");
}
}
}
return hash;
}
static private ByteGrid[][] create_byte_grid_grid(byte[][] greyscale_bytes, out int remaining_height, out int remaining_width)
{
//if (!is_rectangular_2D_array(greyscale_bytes, 5, 5))
//{
// remaining_height = 0;
// remaining_width = 0;
// return null;
//}
int data_height = greyscale_bytes.Length;
int data_width = greyscale_bytes[0].Length;
int hash_height = calculate_hash_height();
int hash_width = calculate_hash_width();
int result_height = data_height / hash_height;
int result_width = data_width / hash_width;
remaining_height = data_height % hash_height;
remaining_width = data_width % hash_width;
// account for indivisible picture dimensions
if (remaining_height > 0)
{
result_height++;
}
if (remaining_width > 0)
{
result_width++;
}
// get the bytegrids
List <ByteGrid> grid_list = new List <ByteGrid>();
for (int grid_height_index = 0; grid_height_index < result_height; grid_height_index++)
{
for (int grid_width_index = 0; grid_width_index < result_width; grid_width_index++)
{
// in the correct grid area of the 2D byte array,
// now copy the appropriate bytes over to the
// temp byte[][], make a ByteGrid out of them, and
// push it into the list
// get the starting, top-left corner of the 2-D byte array you're going to convert to a ByteGrid
int byte_height_index = grid_height_index * hash_height;
byte[][] grid_arr = new byte[hash_height][];
for (int i = 0; i < hash_height; i++)
{
grid_arr[i] = new byte[hash_width];
int byte_width_index = grid_width_index * hash_width;
for (int j = 0; j < hash_width; j++)
{
if (byte_height_index >= greyscale_bytes.Length)
{
grid_arr[i][j] = 255; // make the unexisting bit white
}
else if (byte_width_index >= greyscale_bytes[byte_height_index].Length)
{
grid_arr[i][j] = 255; // make the unexisting bit white
}
else
{
grid_arr[i][j] = greyscale_bytes[byte_height_index][byte_width_index];
}
++byte_width_index;
}
byte_height_index++;
}
grid_list.Add(new ByteGrid(grid_arr));
}
}
// push the bytegrids into the result array and return it.
// prepare the return list
ByteGrid[][] result = new ByteGrid[result_height][];
for (int i = 0; i < result_height; i++)
{
result[i] = new ByteGrid[result_width];
}
int result_height_index = 0;
int result_width_index = 0;
foreach (ByteGrid grid in grid_list)
{
result[result_height_index][result_width_index] = grid;
++result_width_index;
if (result_width_index % result_width == 0)
{
++result_height_index;
result_width_index = 0;
}
}
return(result);
}
