python convert 12 bit image encoded in a string to 8 bit png
- by ks
I have a string that is read from a usb apogee camera that is a 12-bit grayscale image with the 12-bits each occupying the lowest 12 bits of 16-bits words.
I want to create a 8-bit png from this string by ignoring the lowest 4 bits.
I can convert it to a 16-bit image where the highest 4 bits are always zero using PIL with
import Image
imageStr is the image string
imageSize is the image size
img=Image.fromstring("I", imageSize, imageStr, "raw", "I;16", 0,1)
img.save("MyImage.png", "PNG")
Anyway I can do something similar to create a 8-bit image without completely unpacking the string doing arithmetic and making a new string?