First-pass charmap generator script

res/gen_charmap.py

@@ -0,0 +1,119 @@
+#!/usr/bin/env python3
+from PIL import Image, UnidentifiedImageError
+
+CHAR_SIZE = 8
+CHARS_COL = 32
+CHARS_ROW = 32
+
+STD_IMG_W = CHARS_COL * CHAR_SIZE
+STD_IMG_H = CHARS_ROW * CHAR_SIZE
+
+HEADER = f"""
+-- File defining the character to pixel mapping
+
+WIDTH={CHAR_SIZE};
+DEPTH={CHARS_COL * CHARS_ROW * CHAR_SIZE};
+
+ADDRESS_RADIX=UNS;
+DATA_RADIX=BIN;
+
+CONTENT BEGIN
+
+"""
+
+def generate_from_img(f_name):
+    '''
+    Main routine for the program's function flow, taking in a file name 
+    corresponding to a 256x256 image as input (32x32 characters of 8x8 each)
+
+    The standard dimensions can be customized via the constants above
+    '''
+
+    try:
+        bit_img = Image.open(f_name)
+    except FileNotFoundError as e:
+        print(e)
+        return 1
+    except UnidentifiedImageError as e:
+        print(f"The file {f_name} does not correspond to an image!")
+        return 1
+
+    img_h, img_w = bit_img.size
+
+    if img_h < STD_IMG_W or img_w < STD_IMG_H:
+        print(f"Image dimensions are too small (min {img_h}x{img_w})")
+        return 1
+
+    bit_img = bit_img.crop((0, 0, STD_IMG_W, STD_IMG_H))
+
+    if bit_img.mode != '1':
+        bit_img = bit_img.convert('1')
+
+    full_matrix = []
+
+    last_distinct_line = -1
+    last_line_bits = 'xxxxxxxx'
+
+    for char_y in range(CHARS_ROW):
+        full_matrix.append([])
+
+        for char_x in range(CHARS_COL):
+            full_matrix[-1].append("")
+
+            for bit_y in range(8):
+                line_bits = ""
+
+                py = char_y * 8 + bit_y
+
+                line_n = char_y * CHARS_COL * 8 + char_x * 8 + bit_y
+
+                for bit_x in range(8):
+                    px = char_x * 8 + bit_x
+                    line_bits += str(bit_img.getpixel((px, py)) // 255)
+
+                distinct = last_line_bits != line_bits
+
+                if distinct:
+                    if last_distinct_line != -1:
+                        if last_distinct_line == line_n - 1:
+                            full_matrix[-1][-1] += (
+                                f"\t{line_n - 1}  :   {last_line_bits}\n")
+
+                        else:
+                            c_range = f"[{last_distinct_line}..{line_n-1}]"
+                            full_matrix[-1][-1] += (
+                                f"\t{c_range}  :   {last_line_bits}\n")
+
+                    last_line_bits = line_bits
+                    last_distinct_line = line_n
+
+                if bit_y == 7:
+                    if distinct:
+                        full_matrix[-1][-1] += (
+                            f"\t{line_n}  :   {last_line_bits}\n")
+
+                    else:
+                        c_range = f"[{last_distinct_line}..{line_n}]"
+                        full_matrix[-1][-1] += (
+                            f"\t{c_range}  :   {last_line_bits}\n")
+
+                    last_distinct_line = -1
+                    last_line_bits = 'xxxxxxxx'
+
+    full_matrix = "\n".join(["\n".join(row) for row in full_matrix])
+
+    with open('res/charmap.mif', 'w') as f:
+        f.write(HEADER + full_matrix + "\nEND")
+
+    return 0
+
+
+if __name__ == '__main__':
+    f_name = input("File name for the image to use for charmap generation: ")
+
+    error_code = generate_from_img(f_name)
+
+    if error_code:
+        quit()
+
+    print(f"Saved a charmap with {CHARS_COL * CHARS_ROW} characters")