"""Precomputes all possible colours available via NTSC emulation.""" import numpy as np from PIL import Image import screen def main(): s = screen.DHGRScreen(palette=None) colours = {} unique = set() print("import numpy as np") print() print("# Indexed by (trailing 8-bit dot pattern, x % 4)") print("SRGB = {") # For each sequence of 8 pixels, compute the RGB colour of the right-most # pixel, using NTSC emulation. # Double Hi-Res has a timing shift that rotates the displayed bits one # position with respect to NTSC phase. ntsc_shift = 1 for j in range(ntsc_shift, ntsc_shift + 4): bitmap = np.zeros((1, 11 + ntsc_shift), dtype=bool) for bits in range(256): bits8 = np.empty((8,), dtype=bool) for i in range(8): bits8[i] = bits & (1 << i) bitmap[0, j:j + 8] = bits8 # bitmap_to_ntsc produces 3 output pixels for each DHGR input ntsc = s.bitmap_to_image_ntsc(bitmap) last_colour = ntsc[0, 3 * (j + 8) - 1, :] colours[(bits, j - ntsc_shift)] = last_colour unique.add(tuple(last_colour)) print(" (%d, %d): np.array((%d, %d, %d))," % ( bits, j - ntsc_shift, last_colour[0], last_colour[1], last_colour[2])) print("}") print("# %d unique colours" % len(unique)) # Show spectrum of available colours sorted by HSV hue value im = np.zeros((128 * 4, 256 * 16, 3), dtype=np.uint8) for x, j in colours: im[128 * j:128 * (j + 1), x * 16: (x + 1) * 16, :] = colours[x, j] Image.fromarray(im).show() if __name__ == "__main__": main()