Resample to 44100 Hz

Co-authored-by: aider (gemini/gemini-3.1-pro-preview) <aider@aider.chat>

LICENSE

@@ -0,0 +1,23 @@
+Copyright (c) Everyone, except Author
+
+Everyone is permitted to copy, distribute, modify, merge, sell, publish,
+sublicense or whatever they want with this software but at their OWN RISK.
+
+							Preamble
+
+The author has absolutely no clue what the code in this project does.  It might
+just work or not, there is no third option.
+
+
+				GOOD LUCK WITH THAT PUBLIC LICENSE TERMS AND CONDITIONS FOR
+COPYING, DISTRIBUTION, AND MODIFICATION
+
+  0. You just DO WHATEVER YOU WANT TO as long as you NEVER LEAVE A TRACE TO
+TRACK THE AUTHOR of the original product to blame for or hold responsible.
+
+IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
+Good luck and Godspeed.

README.md

@@ -0,0 +1,64 @@
+# Qotplayer
+
+A lightweight, headless Python audio player designed as a fast drop-in replacement for `mpv`. 
+
+This player is specifically built to act as a backend player for **Navidrome** (in Jukebox mode) feeding into **Snapcast**. It avoids the overhead of full `mpv` while maintaining compatibility with its IPC protocol.
+
+This removes about 5 seconds of audio playback lag and UI seeking lag.
+
+## What it does
+
+- Decodes and resamples common audio formats to `48000Hz`, `stereo`, `s16` PCM.
+- Outputs raw PCM audio directly to a FIFO pipe (`/tmp/snapfifo`).
+- Provides a JSON IPC server over a Unix socket for real-time playback control (pause, volume, seek, quit).
+- Maps 0-100 volume levels to 25-100 and applies log scale (for human hearing).
+
+## Setup
+
+docker-compose.yml:
+
+```
+services:
+  navidrome:
+    build: .
+    user: 1000:1000 # should be owner of volumes
+    ports:
+      - "4533:4533"
+    restart: unless-stopped
+    environment:
+      ND_JUKEBOX_ENABLED: true
+      ND_MPVCMDTEMPLATE: '/opt/qotplayer/env/bin/python /opt/qotplayer/main.py %f --input-ipc-server=%s'
+      ND_LOGLEVEL: info
+    volumes:
+      - "./data:/data"
+      - "/mnt/music-combined:/music:ro"
+      - "/tmp/snapfifo:/tmp/snapfifo"
+```
+
+Dockerfile:
+
+```
+FROM deluan/navidrome:latest
+
+RUN apk add --no-cache git curl && \
+    curl -LsSf https://astral.sh/uv/install.sh | sh
+
+ENV PATH="/root/.local/bin:$PATH"
+
+WORKDIR /opt
+RUN git clone https://git.tanner.vc/tanner/qotplayer.git
+
+WORKDIR /opt/qotplayer
+RUN uv venv --python=3.12 env && \
+    . env/bin/activate && \
+    uv pip install -r requirements.txt
+
+RUN chmod 755 /root
+```
+
+Build and run with:
+
+```
+$ sudo docker compose build --no-cache
+$ sudo docker compose up
+```

main.py

@@ -1,4 +1,10 @@
-import os
+import os, logging
+DEBUG = os.environ.get('DEBUG')
+logging.basicConfig(
+        filename='/proc/1/fd/1',
+        format='[%(asctime)s] %(levelname)s %(module)s/%(funcName)s - %(message)s',
+        level=logging.DEBUG if DEBUG else logging.INFO)
+
 import sys
 import json
 import socket
@@ -24,19 +30,7 @@ def playback_thread(file_path, state):
     
     container = av.open(file_path)
     stream = container.streams.audio[0]
-    resampler = av.AudioResampler(format='s16', layout='stereo', rate=48000)
-    
-    def build_graph():
-        graph = av.filter.Graph()
-        src = graph.add_abuffer(template=stream)
-        loudnorm = graph.add("loudnorm", "I=-16:TP=-1.5:LRA=11")
-        sink = graph.add("abuffersink")
-        src.link_to(loudnorm)
-        loudnorm.link_to(sink)
-        graph.configure()
-        return graph
-
-    graph = build_graph()
+    resampler = av.AudioResampler(format='s16', layout='stereo', rate=44100)
     
     with open(fifo_path, 'wb') as fifo:
         iterator = container.decode(stream)
@@ -53,7 +47,6 @@ def playback_thread(file_path, state):
                 with state.lock:
                     state.seek_request = None
                 iterator = container.decode(stream)
-                graph = build_graph()  # Reset filter graph on seek
                 continue
                 
             if paused:
@@ -64,26 +57,24 @@ def playback_thread(file_path, state):
                 frame = next(iterator)
             except StopIteration:
                 break
-            except av.AVError:
+            except av.AVError as e:
+                logging.error(f"AVError during decode: {e}")
                 continue
                 
             with state.lock:
                 state.time_pos = float(frame.pts * stream.time_base)
                 
-            graph.push(frame)
-            while True:
-                try:
-                    filtered_frame = graph.pull()
-                except (av.AVError, BlockingIOError):
-                    break
-                    
-                resampled_frames = resampler.resample(filtered_frame)
+            resampled_frames = resampler.resample(frame)
             for r_frame in resampled_frames:
                 arr = r_frame.to_ndarray()
                 
                 # Apply volume
                 if vol != 100.0:
-                        multiplier = max(0.0, vol / 100.0)
+                    # Linearly map 0-100 to 25-100 so low volumes aren't too quiet
+                    mapped_vol = 25.0 + (vol / 100.0) * 75.0
+                    
+                    # Use cubic curve for more natural volume adjustment (human hearing is logarithmic)
+                    multiplier = max(0.0, (mapped_vol / 100.0) ** 3)
                     arr = arr.astype(np.float32) * multiplier
                     arr = np.clip(arr, -32768, 32767).astype(np.int16)
                     
@@ -131,7 +122,7 @@ def handle_ipc_client(conn, state):
                             if prop == "pause":
                                 state.paused = bool(val)
                             elif prop == "volume":
-                                state.volume = float(val)
+                                state.volume = max(0.0, min(100.0, float(val)))
                             elif prop == "time-pos":
                                 state.seek_request = float(val)
                             else:
@@ -142,11 +133,14 @@ def handle_ipc_client(conn, state):
                     else:
                         resp["error"] = "unknown command"
                         
+                    logging.info(f"IPC Command: {cmd} -> Response: {resp}")
                     conn.sendall((json.dumps(resp) + '\n').encode('utf-8'))
                 except Exception as e:
+                    logging.error(f"IPC Error processing line '{line}': {e}")
                     err_resp = {"error": str(e)}
                     conn.sendall((json.dumps(err_resp) + '\n').encode('utf-8'))
-        except Exception:
+        except Exception as e:
+            logging.error(f"IPC Client connection error: {e}")
             break
     conn.close()
 
@@ -167,7 +161,8 @@ def ipc_server_thread(socket_path, state):
             t.start()
         except socket.timeout:
             continue
-        except Exception:
+        except Exception as e:
+            logging.error(f"IPC Server error: {e}")
             break
             
     server.close()