aspect ratio and keep awake

test_contact_sheet.py

@@ -92,12 +92,13 @@ def check_layout_combos():
             assert ys == sorted(ys), f"pps={pps} spp={spp} strip {strip_i}: not top-to-bottom"
             for a, b in zip(rects, rects[1:]):
                 assert b[1] >= a[1] + a[3], "photos overlap vertically"
-            # Cell aspect must match the chosen mode.
+            # Cell aspect must be exactly 4:3 (3:4 when rotated) to match
+            # the captured photos, within integer rounding of the layout.
             cw, ch = rects[0][2], rects[0][3]
-            if layout["mode"] == "portrait_ccw":
-                assert ch >= cw, f"portrait_ccw cell not taller than wide"
-            else:
-                assert cw >= ch, f"landscape_none cell not wider than tall"
+            want = 3 / 4 if layout["mode"] == "portrait_ccw" else 4 / 3
+            assert abs(cw / ch - want) < 0.02, (
+                f"pps={pps} spp={spp} {layout['mode']}: cell {cw}x{ch} "
+                f"aspect {cw / ch:.4f} != ~{want:.4f}")
 
         # Footer sits below the column, aligned in x, same width.
         for strip_i in range(spp):
@@ -121,7 +122,11 @@ def check_layout_combos():
                            margin=120, photo_gutter=30, strip_gutter=30,
                            auto_orient=True)
             from PIL import Image as _I
-            sheet = _I.open(out).convert("RGB")
+            with _I.open(out) as opened:
+                dpi = opened.info.get("dpi", (0, 0))
+                assert abs(dpi[0] - 300) <= 1 and abs(dpi[1] - 300) <= 1, \
+                    f"sheet dpi metadata wrong: {dpi} (want ~300)"
+                sheet = opened.convert("RGB")
             assert sheet.size == (page_w, page_h)
 
             for i, r in enumerate(layout["photo_rects"]):