code

def captureTestImage(settings, width, height):
     #command defined here
     subprocess.run(command[0],shell=True,executable="/usr/bin/bash")
     imageData = BytesIO()
     imageData.write(subprocess.check_output(command, shell=True))
     imageData.seek(0)
     im = Image.open(imageData)  # SEEMS TO FAIL HERE
     im.save(imageData, "JPG")
     imageData.seek(0)
     buffer = imageData.read()
     imageData.close()
     return im, buffer

actual error receiving:

  im = Image.open(imageData)
  File "/home/user/.local/lib/python3.9/site-packages/PIL/Image.py", line 3339, in open
    raise UnidentifiedImageError(msg)
PIL.UnidentifiedImageError: cannot identify image file <_io.BytesIO object at 0x7fbbf04b30>

What is going wrong here?

This is creating an actual image file, but the script is returning this error- why? How can I fix? Thank you