Add simple Music Player app

Currently only handles mono wav files - to be improved.
2026-05-20 11:51:27 -07:00 · 2025-10-27 23:06:31 +01:00
parent 2ca51708fa
commit d149883a08
3 changed files with 121 additions and 0 deletions
@@ -0,0 +1,24 @@
+{
+"name": "Music Player",
+"publisher": "MicroPythonOS",
+"short_description": "Player audio files",
+"long_description": "Traverse around the filesystem and play audio files that you select.",
+"icon_url": "https://apps.micropythonos.com/apps/com.micropythonos.musicplayer/icons/com.micropythonos.musicplayer_0.0.1_64x64.png",
+"download_url": "https://apps.micropythonos.com/apps/com.micropythonos.musicplayer/mpks/com.micropythonos.musicplayer_0.0.1.mpk",
+"fullname": "com.micropythonos.musicplayer",
+"version": "0.0.1",
+"category": "development",
+"activities": [
+    {
+      "entrypoint": "assets/music_player.py",
+      "classname": "MusicPlayer",
+      "intent_filters": [
+        {
+          "action": "main",
+          "category": "launcher"
+        }
+      ]
+    }
+  ]
+}
+
@@ -0,0 +1,97 @@
+from mpos.apps import Activity
+import mpos.sdcard
+import mpos.ui
+# play music
+import machine
+import uos
+from machine import I2S, Pin
+
+class MusicPlayer(Activity):
+
+    # Widgets:
+    file_explorer = None
+
+    def onCreate(self):
+        screen = lv.obj()
+        # the user might have recently plugged in the sd card so try to mount it
+        mpos.sdcard.mount_with_optional_format('/sdcard')
+        self.file_explorer = lv.file_explorer(screen)
+        self.file_explorer.explorer_open_dir('M:/')
+        self.file_explorer.align(lv.ALIGN.CENTER, 0, 0)
+        self.file_explorer.add_event_cb(self.file_explorer_event_cb, lv.EVENT.ALL, None)
+        self.setContentView(screen)
+
+    def onResume(self, screen):
+        # the user might have recently plugged in the sd card so try to mount it
+        mpos.sdcard.mount_with_optional_format('/sdcard') # would be good to refresh the file_explorer so the /sdcard folder shows up
+
+    def file_explorer_event_cb(self, event):
+        event_code = event.get_code()
+        if event_code not in [2,19,23,24,25,26,27,28,29,30,31,32,33,47,49,52]:
+            name = mpos.ui.get_event_name(event_code)
+            print(f"file_explorer_event_cb {event_code} with name {name}")
+            if event_code == lv.EVENT.VALUE_CHANGED:
+                path = self.file_explorer.explorer_get_current_path()
+                clean_path = path[2:] if path[1] == ':' else path
+                file = self.file_explorer.explorer_get_selected_file_name()
+                fullpath = f"{clean_path}{file}"
+                print(f"Selected: {fullpath}")
+                if fullpath.lower().endswith('.wav'):
+                    self.play_wav(fullpath)
+                else:
+                    print("INFO: ignoring unsupported file format")
+
+    def parse_wav_header(self, f):
+        """Parse standard WAV header (44 bytes) and return channels, sample_rate, bits_per_sample, data_size."""
+        header = f.read(44)
+        if header[0:4] != b'RIFF' or header[8:12] != b'WAVE' or header[12:16] != b'fmt ':
+            raise ValueError("Invalid WAV file")
+        audio_format = int.from_bytes(header[20:22], 'little')
+        if audio_format != 1:  # PCM only
+            raise ValueError("Only PCM WAV supported")
+        channels = int.from_bytes(header[22:24], 'little')
+        sample_rate = int.from_bytes(header[24:28], 'little')
+        bits_per_sample = int.from_bytes(header[34:36], 'little')
+        # Skip to data chunk
+        f.read(8)  # 'data' + size
+        data_size = int.from_bytes(f.read(4), 'little')
+        return channels, sample_rate, bits_per_sample, data_size
+
+    def play_wav(self, filename):
+        """Play WAV file via I2S to MAX98357A."""
+        with open(filename, 'rb') as f:
+            try:
+                channels, sample_rate, bits_per_sample, data_size = self.parse_wav_header(f)
+                if bits_per_sample != 16:
+                    raise ValueError("Only 16-bit audio supported")
+                if channels != 1:
+                    raise ValueError("Only mono audio supported (convert with -ac 1 in FFmpeg)")
+	
+                # Configure I2S (TX mode for output)
+                i2s = I2S(0,  # I2S peripheral 0
+                        sck=Pin(2, Pin.OUT),      # BCK
+                        ws=Pin(47, Pin.OUT),      # LRCK
+                        sd=Pin(16, Pin.OUT),      # DIN
+                        mode=I2S.TX,
+                        bits=16,
+                        format=I2S.MONO,
+                        rate=sample_rate,
+                        ibuf=16000)  # Internal buffer size (adjust if audio stutters)
+
+                print(f"Playing {data_size} bytes at {sample_rate} Hz...")
+
+                # Stream data in chunks (16-bit = 2 bytes per sample)
+                chunk_size = 1024 * 2  # 1KB chunks (tune for your RAM)
+                total_read = 0
+                while total_read < data_size:
+                    chunk = f.read(min(chunk_size, data_size - total_read))
+                    if not chunk:
+                        break
+                    i2s.write(chunk)  # Direct byte stream (little-endian matches I2S)
+                    total_read += len(chunk)
+
+                print("Playback finished.")
+            except Exception as e:
+                print(f"Error: {e}")
+            finally:
+                i2s.deinit()  # Clean up