Rating: 3.7

Blue-LSB of all pixels with alpha != 255

```
from BitVector import BitVector
from PIL import Image
import numpy as np

img = Image.open("stego.png")
data = np.array(img.getdata()) # get data as np array
mask = data[:,3]!=255 # only pixels where alpha isn't max
data = data[mask] # apply mask
data = data[:,2]&1 # only get green LSB
BitVector(bitlist=data).get_text_from_bitvector()
```