ComfyUI/tests-unit/comfy_extras_test/text_overlay_alpha_test.py

121 lines
2.7 KiB
Python

import torch
from comfy.cli_args import args as cli_args
if not torch.cuda.is_available():
cli_args.cpu = True
from comfy_extras.nodes_text_overlay import TextOverlay # noqa: E402
TEXT = "Hello"
SIZE = 64
def image(channels, value=0.25, alpha=1.0):
t = torch.full((1, SIZE, SIZE, channels), value)
if channels == 4:
t[..., 3] = alpha
return t
def overlay(images, text=TEXT, outline=True):
return TextOverlay.execute(images, text, 20.0, "#ffffff", "top", "left", outline).result[0]
def rendered_overlay(text=TEXT, outline=True):
return TextOverlay.render_overlay_text(
SIZE, SIZE, text, "top", "left", 20.0, (255, 255, 255, 255), (0, 0, 0, 255) if outline else (0, 0, 0, 0)
)
def test_rgb_draws_text():
src = image(3)
out = overlay(src)
assert out.shape == src.shape
assert not torch.equal(out, src)
def test_rgba_does_not_raise():
src = image(4)
out = overlay(src)
assert out.shape == src.shape
def test_colour_result_matches_the_rgb_case():
from_rgb = overlay(image(3))
from_rgba = overlay(image(4))
assert torch.allclose(from_rgba[..., :3], from_rgb)
def test_opaque_image_stays_opaque():
out = overlay(image(4, alpha=1.0))
assert torch.all(out[..., 3] == 1.0)
def test_text_is_visible_on_a_transparent_image():
"""Coverage has to be added where the glyphs land, or the text is invisible."""
out = overlay(image(4, alpha=0.0))
assert out[..., 3].max() > 0.0
def test_alpha_matches_source_over():
src = image(4, alpha=0.5)
_, overlay_alpha = rendered_overlay()
expected = overlay_alpha + (1.0 - overlay_alpha) * src[..., 3:]
out = overlay(src)
assert torch.allclose(out[..., 3:], expected, atol=1e-6)
def test_semi_transparent_destination_gains_coverage():
"""max(dst, src) would return 0.5 here; source over must exceed it."""
src = image(4, alpha=0.5)
out = overlay(src)
assert out[..., 3].max() > 0.5
def test_transparent_background_does_not_darken_text():
"""Undefined RGB under a fully transparent pixel must not bleed into glyphs."""
src = image(4, value=0.0, alpha=0.0)
out = overlay(src, outline=False)
covered = out[..., 3] > 0.01
assert covered.any()
assert torch.allclose(out[..., :3][covered], torch.ones_like(out[..., :3][covered]), atol=1e-5)
def test_untouched_pixels_keep_their_alpha():
src = image(4, alpha=0.0)
out = overlay(src, text="i")
assert torch.any(out[..., 3] == 0.0)
def test_empty_text_passes_the_image_through():
src = image(4, alpha=0.4)
out = overlay(src, text=" ")
assert torch.equal(out, src)
def test_does_not_mutate_input():
src = image(4, alpha=0.6)
before = src.clone()
overlay(src)
assert torch.equal(src, before)