Add bbox benchmark and additional tests

Author: akx

Tests/benchmarks.py

@@ -87,6 +87,35 @@ def make_pillow_image(
     return im.convert(mode)
 
 
+BBOX_SCENARIOS: dict[str, tuple[float, str] | None] = {
+    "half-centered": (0.5, "center"),
+    "small-centered": (0.1, "center"),
+    "half-corner": (0.5, "corner"),
+    "empty": None,
+}
+
+
+def make_bbox_image(
+    mode: str,
+    size: tuple[int, int],
+    region: tuple[float, str] | None,
+) -> Image.Image:
+    im = Image.new(mode, size, 0)
+    if region is None:
+        return im
+    fraction, placement = region
+    w, h = size
+    bw, bh = max(1, round(w * fraction)), max(1, round(h * fraction))
+    if placement == "center":
+        left, top = (w - bw) // 2, (h - bh) // 2
+    else:
+        left, top = w - bw, h - bh
+    nbands = len(im.getbands())
+    color = (255, 128, 64, 255)[:nbands] if nbands > 1 else 255
+    im.paste(color, (left, top, left + bw - 1, top + bh - 1))
+    return im
+
+
 @pytest.mark.benchmark(group="composition")
 @pytest.mark.parametrize("mode", MODES)
 @pytest.mark.parametrize("size", SIZES, ids=_format_size)
@@ -431,6 +460,21 @@ def test_offset(bench: BenchmarkFixture, mode: str, size: tuple[int, int]) -> No
     bench(ImageChops.offset, im, 123, 45)
 
 
+@pytest.mark.benchmark(group="bbox")
+@pytest.mark.parametrize("scenario", list(BBOX_SCENARIOS))
+@pytest.mark.parametrize("mode", ["L", "LA", "I;16", "RGB", "RGBA"])
+@pytest.mark.parametrize("size", SIZES, ids=_format_size)
+def test_getbbox(
+    bench: BenchmarkFixture,
+    mode: str,
+    size: tuple[int, int],
+    scenario: str,
+) -> None:
+    im = make_bbox_image(mode, size, BBOX_SCENARIOS[scenario])
+    bench.extra_info["label"] = [scenario]
+    bench(im.getbbox)
+
+
 @pytest.mark.benchmark(group="histogram")
 @pytest.mark.parametrize("mode", MODES)
 @pytest.mark.parametrize("size", SIZES, ids=_format_size)

Tests/test_image_getbbox.py

@@ -44,6 +44,28 @@ def check(im: Image.Image, fill_color: int | tuple[int, ...]) -> None:
             check(im, (255, 255))
 
 
+@pytest.mark.parametrize("mode", ("L", "RGB", "RGBA", "I", "F"))
+@pytest.mark.parametrize(
+    "box",
+    (
+        (0, 0, 1, 1),  # single pixel, top-left
+        (99, 0, 100, 1),  # single pixel, top-right
+        (0, 99, 1, 100),  # single pixel, bottom-left
+        (99, 99, 100, 100),  # single pixel, bottom-right
+        (0, 0, 100, 1),  # full top row
+        (0, 99, 100, 100),  # full bottom row
+        (0, 0, 1, 100),  # full left column
+        (99, 0, 100, 100),  # full right column
+        (40, 40, 60, 60),  # centred block
+    ),
+)
+def test_bbox_edges(mode: str, box: tuple[int, int, int, int]) -> None:
+    im = Image.new(mode, (100, 100), 0)
+    bands = Image.getmodebands(mode)
+    im.paste(255 if bands == 1 else (255,) * bands, box)
+    assert im.getbbox() == box
+
+
 @pytest.mark.parametrize("mode", ("RGBA", "RGBa", "La", "LA", "PA"))
 def test_bbox_alpha_only_false(mode: str) -> None:
     im = Image.new(mode, (100, 100))