I really like the 15 color palette, it really "pops" and that's super important. Minus one color seems totally worth it. Which diode did you use in particular? It just says "schottky diode" on the schematic, no other identification.Code: Select all
from PIL import Image
im = Image.open("finch-indexed.png")
with open("finch-indexed.img", "wb") as f:
f.write(im.tobytes())
f.close()
Code: Select all
from PIL import Image
im = Image.open("finch-640x480x3bpp.png")
print(im.size)
print(im.getpalette())
reddata = []
greenbluedata = []
def pack(bit,*v):
r = 0
for x in v:
r <<= 1
if x & bit:
r += 1
return r
for y in range(im.height):
for x in range(0, im.width, 4):
v0 = im.getpixel((x,y))
v1 = im.getpixel((x+1,y))
v2 = im.getpixel((x+2,y))
v3 = im.getpixel((x+3,y))
r = pack(1, v0, v1, v2, v3)
g = pack(2, v0, v1, v2, v3)
b = pack(4, v0, v1, v2, v3)
reddata.append(r)
greenbluedata.append((g << 4) + b)
print(len(reddata), len(greenbluedata))
with open("imgfinch.dat", "wb") as fp:
fp.write(bytes(reversed(greenbluedata)))
fp.write(bytes(reversed(reddata)))
fp.close()
Code: Select all
from PIL import Image
from PIL import ImagePalette
# Create a palette that matches what the hardware does
palette = []
for v in range(16):
base = 0
mag = 160
if v>=8:
base += 255-mag
r = base + mag * ((v>>2)&1)
g = base + mag * ((v>>1)&1)
b = base + mag * ((v>>0)&1)
palette.extend((r,g,b))
# Make a copy of the palette with some bias towards 0x80, so that the quantization works better
palettedata = []
bias = 12
for v in range(16):
r,g,b = palette[3*v:3*(v+1)]
r = bias + (r * (0xff-2*bias)) // 0xff
g = bias + (g * (0xff-2*bias)) // 0xff
b = bias + (b * (0xff-2*bias)) // 0xff
palettedata.extend((r,g,b))
# PIL requires 256-colour palettes
palettedata.extend([0] * (768-len(palettedata)))
# PIL has a quirky API that requires us to wrap an image around the palette in order to use it
palimage = Image.new("P", (1,1))
palimage.putpalette(palettedata)
im = Image.open("finch.jpg")
im2 = im.resize((160,100)).quantize("P", palette=palimage, kmeans=10)
im2.save("finch2.png")
# Save out a scaled-up version of the palettized image so that it's easier to see for debugging
scale = 8
im3 = Image.new("RGB", (im2.width*scale,im2.height*scale))
for y in range(im2.height):
for x in range(im2.width):
v = im2.getpixel((x,y)) & 15
for v in range(16):
r,g,b = palette[3*v:3*(v+1)]
r = bias + (r * (0xff-2*bias)) // 0xff
g = bias + (g * (0xff-2*bias)) // 0xff
b = bias + (b * (0xff-2*bias)) // 0xff
palettedata.extend((r,g,b))
r,g,b = palette[3*v:3*(v+1)]
for xx in range(scale):
for yy in range(scale):
im3.putpixel((x*scale+xx,y*scale+yy),(r,g,b))
im3.save("finch3.png")
# Save out the binary data
with open("finch.img", "wb") as f:
f.write(im2.tobytes())
f.close()
