Try both readpicture and albumart, prefer the former

src/mpd_now_playable/mpd/artwork_cache.py

@@ -6,7 +6,7 @@ from ..async_tools import run_background_task
 from ..cache import Cache, make_cache
 from .types import CurrentSongResponse, MpdStateHandler
 
-CACHE_TTL = 60 * 60 # seconds = 1 hour
+CACHE_TTL = 60 * 60  # seconds = 1 hour
 
 
 class ArtCacheEntry(TypedDict):
@@ -49,7 +49,7 @@ class MpdArtworkCache:
 		return None
 
 	async def cache_artwork(self, song: CurrentSongResponse) -> None:
-		art = ArtCacheEntry(data=await self.mpd.readpicture(song["file"]))
+		art = ArtCacheEntry(data=await self.mpd.get_art(song["file"]))
 		try:
 			await self.album_cache.add(calc_album_key(song), art, ttl=CACHE_TTL)
 		except ValueError:

src/mpd_now_playable/mpd/listener.py

@@ -95,6 +95,12 @@ class MpdStateListener(Player):
 		print(song)
 		listener.update(song)
 
+	async def get_art(self, file: str) -> bytes | None:
+		picture = await self.readpicture(file)
+		if picture:
+			return picture
+		return await self.albumart(file)
+
 	async def albumart(self, file: str) -> bytes | None:
 		try:
 			albumart = await self.client.albumart(file)

src/mpd_now_playable/mpd/types.py

@@ -2,11 +2,9 @@ from typing import Literal, NotRequired, Protocol, TypedDict
 
 
 class MpdStateHandler(Protocol):
-	async def readpicture(self, file: str) -> bytes | None:
-		...
+	async def get_art(self, file: str) -> bytes | None: ...
 
-	async def refresh(self) -> None:
-		...
+	async def refresh(self) -> None: ...
 
 
 BooleanFlag = Literal["0", "1"]