What did you do?
import sys
from PIL import Image
i = Image.open(sys.argv[1])
o = Image.new(mode="RGB", size=i.size)
o.putdata([r << 16 | g << 8 | b for r, g, b in i.getdata()])
o.save(sys.argv[2])
What did you expect to happen?
I expected this to have the input and output identical (normal case, no transparency etc)
What actually happened?
The output seems to expect BGR pixel format data, not RGB. I don't know if it's a bug or a documentation issue here. If this is expected, the doc probably needs some clarification about endianness and actual memory layout expected.
What are your OS, Python and Pillow versions?
- OS: Linux x86_64
- Python: 3.13.3
- Pillow: 11.2.1
--------------------------------------------------------------------
Pillow 11.2.1
Python 3.13.3 (main, Apr 9 2025, 07:44:25) [GCC 14.2.1 20250207]
--------------------------------------------------------------------
Python executable is /usr/bin/python3
System Python files loaded from /usr
--------------------------------------------------------------------
Python Pillow modules loaded from /usr/lib/python3.13/site-packages/PIL
Binary Pillow modules loaded from /usr/lib/python3.13/site-packages/PIL
--------------------------------------------------------------------
--- PIL CORE support ok, compiled for 11.2.1
--- TKINTER support ok, loaded 8.6
--- FREETYPE2 support ok, loaded 2.13.3
--- LITTLECMS2 support ok, loaded 2.17
--- WEBP support ok, loaded 1.5.0
*** AVIF support not installed
--- JPEG support ok, compiled for libjpeg-turbo 3.1.0
--- OPENJPEG (JPEG2000) support ok, loaded 2.5.3
--- ZLIB (PNG/ZIP) support ok, loaded 1.3.1
--- LIBTIFF support ok, loaded 4.7.0
--- RAQM (Bidirectional Text) support ok, loaded 0.10.2
--- LIBIMAGEQUANT (Quantization method) support ok, loaded 4.2.2
--- XCB (X protocol) support ok
--------------------------------------------------------------------
What did you do?
What did you expect to happen?
I expected this to have the input and output identical (normal case, no transparency etc)
What actually happened?
The output seems to expect BGR pixel format data, not RGB. I don't know if it's a bug or a documentation issue here. If this is expected, the doc probably needs some clarification about endianness and actual memory layout expected.
What are your OS, Python and Pillow versions?