Files
FabledCurator/tests/test_phash_util.py
T
2026-05-17 22:02:42 -04:00

52 lines
1.7 KiB
Python

import io
import imagehash
from PIL import Image
from backend.app.utils.phash import compute_phash, find_similar
def _img(color, size=(64, 64)):
return Image.new("RGB", size, color)
def test_compute_phash_stable_and_hex():
h1 = compute_phash(_img((10, 120, 200)))
h2 = compute_phash(_img((10, 120, 200)))
assert isinstance(h1, str) and len(h1) == 16 # hash_size=8 -> 64-bit -> 16 hex
assert h1 == h2
def test_compute_phash_none_for_non_image():
assert compute_phash(io.BytesIO(b"not an image")) is None
def test_find_similar_none_when_far():
new = compute_phash(_img((0, 0, 0)))
cand = (compute_phash(_img((255, 255, 255))), 100, 100, 7)
rel, mid = find_similar(new, 50, 50, [cand], threshold=2)
assert rel == "none" and mid is None
def test_find_similar_larger_exists_skips_new():
h = compute_phash(_img((123, 50, 7)))
rel, mid = find_similar(h, 100, 100, [(h, 400, 400, 9)], threshold=2)
assert rel == "larger_exists" and mid == 9
def test_find_similar_smaller_exists_supersede():
h = compute_phash(_img((123, 50, 7)))
rel, mid = find_similar(h, 800, 800, [(h, 100, 100, 4)], threshold=2)
assert rel == "smaller_exists" and mid == 4
def test_find_similar_threshold_boundary_inclusive_and_first_match():
h = compute_phash(_img((10, 10, 10)))
far = compute_phash(_img((240, 240, 240)))
d = imagehash.hex_to_hash(h) - imagehash.hex_to_hash(far)
# at exactly the distance, it counts as similar (<=)
rel, _ = find_similar(h, 10, 10, [(far, 999, 999, 1)], threshold=d)
assert rel == "larger_exists"
rel2, _ = find_similar(h, 10, 10, [(far, 999, 999, 1)], threshold=d - 1)
assert rel2 == "none"