[BUG] b command doesn't work, PILImage self is "RGB"

[lukas-buergi]

Describe the bug
The b command doesn't work for me. I have no idea why, but I found a simple fix.

To Reproduce
Steps to reproduce the behavior:

1. Run for example ffmpeg -hide_banner -loglevel quiet -i C0040.MP4 -ss 10 -t 1 -an -f rawvideo -pix_fmt rgb24 pipe:1 | rembg b 2160 3840 | ffmpeg -f image2pipe -framerate 60 -i pipe:1 -c:v libx265 -crf 23 output.mp4
2. See error

File "/mnt/deb67853-226b-4939-9bd1-3167199a8160/rembg/env/lib/python3.11/site-packages/rembg/commands/b_command.py", line 165, in main
    img = PILImage.frombytes("RGB", (image_width, image_height), img_bytes)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/mnt/deb67853-226b-4939-9bd1-3167199a8160/rembg/env/lib/python3.11/site-packages/PIL/Image.py", line 858, in frombytes
    if self.width == 0 or self.height == 0:
       ^^^^^^^^^^
AttributeError: 'str' object has no attribute 'width'

3. If you want, use pdb to investigate. It turns out that self == "RGB".

Expected behavior
The background should have been removed from the video.

OS Version:
debian 12

Rembg version:
37bbf63 (also latest version on pip has same behaviour)

Solution

import PIL
...
img = PIL.Image.frombytes("RGB", (image_width, image_height), img_bytes)

If you know why this helps, I would be glad to find out.

[calledit]

Have the same issue.

$ cat raw_rgb24.dat| rembg b 1440 1080 | cat -> rgb.dat

File "/Users/me/main_venv/lib/python3.11/site-packages/PIL/Image.py", line 858, in frombytes
    if self.width == 0 or self.height == 0:
       ^^^^^^^^^^
AttributeError: 'str' object has no attribute 'width'