Convert PIL Image to byte array?

I have an image in PIL Image format. I need to convert it to byte array.

img = Image.open(fh, mode='r')  
roiImg = img.crop(box)

Now I need the roiImg as a byte array.

Answer

Thanks everyone for your help.

Finally got it resolved!!

import io

img = Image.open(fh, mode='r')
roi_img = img.crop(box)

img_byte_arr = io.BytesIO()
roi_img.save(img_byte_arr, format='PNG')
img_byte_arr = img_byte_arr.getvalue()

With this i don’t have to save the cropped image in my hard disc and I’m able to retrieve the byte array from a PIL cropped image.