Files
ComfyUI/tests-unit/comfy_api_nodes_test/image_conversions_test.py
Christian Byrne a9ab2b62da [Partner Nodes] Stop adding an opaque alpha channel to API node images (#15369)
* Stop adding an opaque alpha channel to API node images

bytesio_to_image_tensor converted every downloaded image to RGBA, so nodes
whose API returns no transparency still emitted a 4 channel IMAGE. Keep the
alpha when the decoded image has one, stay RGB when it does not.

---------

Signed-off-by: bigcat88 <bigcat88@icloud.com>
Co-authored-by: bigcat88 <bigcat88@icloud.com>
2026-08-15 21:27:24 +04:00

81 lines
2.5 KiB
Python

from io import BytesIO
import pytest
import torch
from PIL import Image
from comfy.cli_args import args
if not torch.cuda.is_available():
args.cpu = True
from comfy_api_nodes.util.conversions import bytesio_to_image_tensor, pad_images_to_common_channels # noqa: E402
def encode(image: Image.Image, image_format: str = "PNG") -> BytesIO:
buffer = BytesIO()
image.save(buffer, format=image_format)
buffer.seek(0)
return buffer
def test_rgb_png_stays_three_channels():
tensor = bytesio_to_image_tensor(encode(Image.new("RGB", (4, 4), (10, 20, 30))))
assert tensor.shape == (1, 4, 4, 3)
def test_jpeg_stays_three_channels():
tensor = bytesio_to_image_tensor(encode(Image.new("RGB", (4, 4), (10, 20, 30)), "JPEG"))
assert tensor.shape == (1, 4, 4, 3)
def test_grayscale_is_expanded_to_rgb():
tensor = bytesio_to_image_tensor(encode(Image.new("L", (4, 4), 128)))
assert tensor.shape == (1, 4, 4, 3)
def test_rgba_png_keeps_its_alpha():
tensor = bytesio_to_image_tensor(encode(Image.new("RGBA", (4, 4), (10, 20, 30, 0))))
assert tensor.shape == (1, 4, 4, 4)
assert tensor[..., 3].max() == 0.0
def test_palette_png_with_transparency_keeps_its_alpha():
image = Image.new("P", (4, 4), 1)
image.putpalette([0, 0, 0, 255, 255, 255])
image.info["transparency"] = 0
image.putpixel((0, 0), 0)
tensor = bytesio_to_image_tensor(encode(image))
assert tensor.shape == (1, 4, 4, 4)
assert tensor[0, 0, 0, 3] == 0.0
assert tensor[0, 1, 1, 3] == 1.0
@pytest.mark.parametrize("mode,channels", [("RGB", 3), ("RGBA", 4)])
def test_explicit_mode_is_respected(mode, channels):
tensor = bytesio_to_image_tensor(encode(Image.new("RGBA", (4, 4), (10, 20, 30, 128))), mode=mode)
assert tensor.shape == (1, 4, 4, channels)
def test_pad_mixed_channels_concatenates():
rgb = torch.rand(1, 4, 4, 3)
rgba = torch.rand(2, 4, 4, 4)
padded = pad_images_to_common_channels([rgb, rgba])
result = torch.cat(padded, dim=0)
assert result.shape == (3, 4, 4, 4)
def test_pad_adds_opaque_alpha_and_keeps_rgb_values():
rgb = torch.rand(1, 4, 4, 3)
rgba = torch.rand(1, 4, 4, 4)
padded_rgb, padded_rgba = pad_images_to_common_channels([rgb, rgba])
assert torch.equal(padded_rgb[..., :3], rgb)
assert padded_rgb[..., 3].min() == 1.0
assert padded_rgba is rgba
def test_pad_leaves_homogeneous_channels_unchanged():
images = [torch.rand(1, 4, 4, 3), torch.rand(2, 4, 4, 3)]
padded = pad_images_to_common_channels(images)
assert all(p is i for p, i in zip(padded, images))