Fix weird audio noise and make audio separate from video

Author: unexploredtest

cnds/cnds.cpp

@@ -18,6 +18,7 @@ NB_MODULE(cnds, m) {
         .def("get_top_nds_frame", &Nds::getTopNdsFrame)
         .def("get_bot_nds_frame", &Nds::getBotNdsFrame)
         .def("get_audio_samples", &Nds::getAudioSamples)
+        .def("get_audio_buffer_number", &Nds::getAudioBufferNumber)
 
         // Save methods
         .def("save_state", &Nds::saveState)

cnds/include/nds.hpp

@@ -23,6 +23,7 @@ class Nds {
 
         // Audio methods
         nb::ndarray<nb::numpy, int16_t> getAudioSamples(int count);
+        uint32_t getAudioBufferNumber();
 
         // Savestate methods
         void saveState(std::string path);

cnds/nds.cpp

@@ -82,6 +82,10 @@ nb::ndarray<nb::numpy, int16_t> Nds::getAudioSamples(int count) {
     return nb::ndarray<nb::numpy, int16_t>(samples, {(size_t)count, 2}, owner);
 }
 
+uint32_t Nds::getAudioBufferNumber() {
+    return m_core->spu.getBufferNumber();
+}
+
 void Nds::saveState(std::string path) {
     m_core->saveStates.setPath(path, m_isGba);
     m_core->saveStates.saveState();

externals/NooDS

@@ -0,0 +1,37 @@
+import time
+import threading
+
+import sounddevice as sd
+import numpy as np
+
+
+class Audio:
+    def __init__(self, pynds) -> None:
+        self._pynds = pynds
+
+        self.running = False
+
+    def start(self) -> None:
+        self.stream = sd.OutputStream(samplerate=32768, channels=2, dtype='int16', blocksize=0)
+        self.running = True
+
+        self.audio_thread = threading.Thread(target=self.play_audio)
+        self.audio_thread.start()
+
+    def close(self) -> None:
+        if (self.running):
+            self.running = False
+            self.audio_thread.join()
+
+    def play_audio(self):
+        self.stream.start()
+
+        while (self.running):
+            samples = self._pynds.get_audio(699)
+            data_to_write = np.ascontiguousarray(samples)
+            self.stream.write(data_to_write)
+
+            time.sleep(0.001)
+
+        self.stream.stop()
+        self.stream.close()

pynds/audio.py

@@ -6,6 +6,7 @@
 from .memory import Memory
 from .button import Button
 from .window import Window
+from .audio import Audio
 from .config import config
 
 
@@ -23,6 +24,7 @@ def __init__(self, path: str, save_path: str = "", auto_detect: bool = True, is_
         self.button = Button(self._nds)
         self.memory = Memory(self._nds)
         self.window = Window(self)
+        self.audio = Audio(self)
 
     def get_is_gba(self) -> bool:
         return self.is_gba
@@ -57,6 +59,9 @@ def get_frame_shape(self) -> Tuple[int, int]:
     def get_audio(self, count: int = 699) -> np.ndarray:
         return self._nds.get_audio_samples(count)
 
+    def get_audio_buffer_number(self) -> int:
+        return self._nds.get_audio_buffer_number()
+
     def open_window(self, width: int = 800, height: int = 800) -> None:
         if (self.window.running):
             self.window.close()
@@ -66,6 +71,15 @@ def open_window(self, width: int = 800, height: int = 800) -> None:
     def close_window(self) -> None:
         self.window.close()
 
+    def open_audio(self) -> None:
+        if (self.audio.running):
+            self.audio.close()
+
+        self.audio.start()
+
+    def close_audio(self) -> None:
+        self.audio.close()
+
     def render(self) -> None:
         if (self.window.running):
             self.window.render()

pynds/pynds.py

@@ -10,12 +10,10 @@ def __init__(self, pynds) -> None:
         self.running = False
 
     def init(self, width: int, height: int) -> None:
-        pygame.mixer.pre_init(frequency=44100, size=-16, channels=2, buffer=512)
         pygame.init()
         self.screen = pygame.display.set_mode((width, height), pygame.RESIZABLE)
         pygame.display.set_caption("PyNDS")
         self.running = True
-        self._audio_buffer = np.zeros((0, 2), dtype=np.int16)  # continuous buffer
 
     def close(self) -> None:
         pygame.quit()
@@ -30,9 +28,6 @@ def render(self) -> None:
             elif (self.running):
                 self.process_frame_nds()
 
-            if (self.running):
-                self.process_audio()
-
     def handle_events(self) -> None:
         for event in pygame.event.get():
             if event.type == pygame.QUIT:
@@ -142,33 +137,3 @@ def process_frame_nds(self):
         surface = pygame.transform.scale(surface, (width, height // 2))
         self.screen.blit(surface, surface.get_rect(topleft=(0, height // 2)))
         pygame.display.flip()
-
-    def process_audio(self):
-        samples = self._pynds.get_audio(699)
-        if samples is not None and len(samples) > 0:
-            # Resample 32768 -> 44100
-            ratio = 44100 / 32768
-            new_len = int(len(samples) * ratio)
-            left = np.interp(
-                np.linspace(0, len(samples), new_len),
-                np.arange(len(samples)),
-                samples[:, 0].astype(np.float32)
-            ).astype(np.int16)
-            right = np.interp(
-                np.linspace(0, len(samples), new_len),
-                np.arange(len(samples)),
-                samples[:, 1].astype(np.float32)
-            ).astype(np.int16)
-            resampled = np.column_stack((left, right))
-            self._audio_buffer = np.concatenate((self._audio_buffer, resampled))
-
-        # Only play when we have enough buffered samples
-        CHUNK = 2048
-        while len(self._audio_buffer) >= CHUNK:
-            chunk = np.ascontiguousarray(self._audio_buffer[:CHUNK])
-            self._audio_buffer = self._audio_buffer[CHUNK:]
-            # Find a free channel or wait
-            ch = pygame.mixer.find_channel(False)
-            if ch is not None:
-                sound = pygame.sndarray.make_sound(chunk)
-                ch.play(sound)

pynds/window.py

@@ -90,7 +90,7 @@ def build_extensions(self):
 
 setup(name='pynds',
       packages=find_packages(),
-      install_requires=['numpy', 'pygame'],
+      install_requires=['numpy', 'pygame', 'sounddevice'],
       version=version,
       description='Python bindings for NooDS',
       author='unexploredtest',