diff --git a/tests/test_round17.py b/tests/test_round17.py
index 529553c..8089338 100644
--- a/tests/test_round17.py
+++ b/tests/test_round17.py
@@ -397,36 +397,40 @@ class TestAlbumWideArt:
                for t in album_tracks(library, "Artist", "Great Album")}
         assert ids == {1, 2, 3}
 
-    def _dialog(self, qapp, monkeypatch, track_count, album_count):
+    def _dialog(self, monkeypatch, image, track_count, album_count):
         from lintunes.art_search import AlbumArtFetcher, ArtCandidate
         from lintunes.gui.album_art_dialog import AlbumArtDialog
-        # No network: capture the fetch and feed the image back by hand.
+        # No network: neuter the fetch and feed the image back by hand.
         monkeypatch.setattr(AlbumArtFetcher, "fetch", lambda self, c: None)
         candidate = ArtCandidate(artist="A", album="B", art_url="https://x")
         dialog = AlbumArtDialog([candidate], track_count,
                                 album_count=album_count)
-        dialog._on_image({"candidate": candidate, "image": b"img",
-                          "mime": "image/png"})
+        dialog._on_image({"candidate": candidate, "image": image,
+                          "mime": "image/jpeg"})
         return dialog
 
-    def test_album_button_applies_to_whole_album(self, qapp, monkeypatch):
-        dialog = self._dialog(qapp, monkeypatch, track_count=1, album_count=12)
+    def test_album_button_applies_to_whole_album(self, qapp, monkeypatch,
+                                                 jpeg_bytes):
+        dialog = self._dialog(monkeypatch, jpeg_bytes,
+                              track_count=1, album_count=12)
         assert dialog._album_btn is not None
         assert dialog._album_btn.isEnabled()
         assert "12" in dialog._album_btn.text()
         assert not dialog.apply_to_album
         dialog._accept_album()
         assert dialog.apply_to_album
-        assert dialog.selected_image == b"img"
-        assert dialog.selected_mime == "image/png"
+        assert dialog.selected_image == jpeg_bytes
+        assert dialog.selected_mime == "image/jpeg"
 
     def test_no_album_button_when_selection_covers_album(self, qapp,
-                                                         monkeypatch):
-        dialog = self._dialog(qapp, monkeypatch, track_count=5, album_count=5)
+                                                         monkeypatch,
+                                                         jpeg_bytes):
+        dialog = self._dialog(monkeypatch, jpeg_bytes,
+                              track_count=5, album_count=5)
         assert dialog._album_btn is None
         dialog._accept_current()
         assert not dialog.apply_to_album
-        assert dialog.selected_image == b"img"
+        assert dialog.selected_image == jpeg_bytes
 
 
 # ---- context menu exposes the new action's signal ----