analog_input_gain (#21)

- add input boost slider
- add level meter

Reviewed-on: https://gitea.pstruebi.xyz/auracaster/bumble-auracast/pulls/21

src/auracast/multicast.py

@@ -638,6 +638,12 @@ class Streamer():
         except Exception:
             pass
 
+    def get_audio_levels(self) -> list[float]:
+        """Return current RMS audio levels (0.0-1.0) for each BIG."""
+        if not self.bigs:
+            return []
+        return [big.get('_audio_level_rms', 0.0) for big in self.bigs.values()]
+
     async def stream(self):
 
         bigs = self.bigs
@@ -867,6 +873,11 @@ class Streamer():
                         np.clip(pcm_arr, -32768, 32767, out=pcm_arr)
                         pcm_frame = pcm_arr.astype(np.int16).tobytes()
 
+                    # Compute RMS audio level (normalized 0.0-1.0) for level monitoring
+                    pcm_samples = np.frombuffer(pcm_frame, dtype=np.int16).astype(np.float32)
+                    rms = np.sqrt(np.mean(pcm_samples ** 2)) / 32768.0 if len(pcm_samples) > 0 else 0.0
+                    big['_audio_level_rms'] = float(rms)
+
                     # Measure LC3 encoding time
                     t1 = time.perf_counter()
                     num_bis = big.get('num_bis', 1)

src/auracast/multicast_control.py

@@ -37,6 +37,12 @@ class Multicaster:
             'is_initialized': self.is_auracast_init,
             'is_streaming': streaming,
         }
+
+    def get_audio_levels(self) -> list[float]:
+        """Return current RMS audio levels (0.0-1.0) for each BIG."""
+        if self.streamer is not None and self.streamer.is_streaming:
+            return self.streamer.get_audio_levels()
+        return []
     
     async def init_broadcast(self):
         self.device_acm = multicast.create_device(self.global_conf)

src/auracast/server/multicast_frontend.py

@@ -1,6 +1,7 @@
 # frontend/app.py
 import os
 import time
+import math
 import logging as log
 from PIL import Image
 
@@ -197,22 +198,28 @@ else:
     start_stream, stop_stream = render_stream_controls(is_streaming, "Start Auracast", "Stop Auracast", running_mode, secondary_is_streaming)
 
 # Analog gain control (only for Analog mode, placed below start button)
-analog_gain_value = 50  # default
+analog_gain_value = 50  # default (ALSA 10-60 range)
 software_boost_db = 0  # default
 if audio_mode == "Analog":
     saved_analog_gain = saved_settings.get('analog_gain', 50)
-    analog_gain_value = st.slider(
+    # Convert persisted ALSA value (10-60) to display value (0-100)
+    saved_display = int(round((saved_analog_gain - 10) * 100 / 50))
+    saved_display = max(0, min(100, saved_display))
+    analog_gain_display = st.slider(
         "Analog Input Gain",
-        min_value=10,
-        max_value=60,
-        value=min(saved_analog_gain, 60),
+        min_value=0,
+        max_value=100,
+        value=saved_display,
         step=5,
         disabled=is_streaming,
-        help="ADC gain level for both analog inputs (10-60%). Default is 50%."
+        format="%d%%",
+        help="ADC gain level for both analog inputs. Default is 80%."
     )
+    # Map display value (0-100) back to ALSA range (10-60)
+    analog_gain_value = int(round(10 + analog_gain_display * 50 / 100))
     saved_boost = saved_settings.get('software_boost_db', 0)
     software_boost_db = st.slider(
-        "Software Boost (dB)",
+        "Boost",
         min_value=0,
         max_value=20,
         value=min(int(saved_boost), 20),
@@ -221,6 +228,56 @@ if audio_mode == "Analog":
         help="Digital gain boost applied before encoding (0-20 dB). Use this when the line-level signal is too quiet even at max ADC gain. Higher values may cause clipping on loud signals."
     )
 
+# Audio level monitor (checkbox, not persisted across reloads)
+show_level_monitor = st.checkbox("Audio level monitor", value=False, disabled=not is_streaming,
+                                  help="Show real-time audio level meters for active radios. Only works while streaming.")
+
+if show_level_monitor and is_streaming:
+    @st.fragment(run_every=0.2)
+    def _audio_level_fragment():
+        cols = st.columns(2)
+        # Radio 1
+        with cols[0]:
+            try:
+                r = requests.get(f"{BACKEND_URL}/audio_level", timeout=0.2)
+                levels = r.json().get("levels", []) if r.ok else []
+            except Exception:
+                levels = []
+            if levels:
+                rms = max(levels)
+                db = max(-60.0, 20.0 * (math.log10(rms) if rms > 0 else -3.0))
+                pct = int(max(0, min(100, (db + 60) * 100 / 60)))
+                st.markdown(
+                    f"**Radio 1**"
+                    f'<div style="background:#333;border-radius:4px;height:18px;width:100%;margin-top:4px;">'
+                    f'<div style="background:#2ecc71;height:100%;width:{pct}%;border-radius:4px;transition:width 0.15s;"></div>'
+                    f'</div>',
+                    unsafe_allow_html=True,
+                )
+            else:
+                st.markdown("**Radio 1** &nbsp; --")
+        # Radio 2
+        with cols[1]:
+            try:
+                r2 = requests.get(f"{BACKEND_URL}/audio_level2", timeout=0.2)
+                levels2 = r2.json().get("levels", []) if r2.ok else []
+            except Exception:
+                levels2 = []
+            if levels2:
+                rms2 = max(levels2)
+                db2 = max(-60.0, 20.0 * (math.log10(rms2) if rms2 > 0 else -3.0))
+                pct2 = int(max(0, min(100, (db2 + 60) * 100 / 60)))
+                st.markdown(
+                    f"**Radio 2**"
+                    f'<div style="background:#333;border-radius:4px;height:18px;width:100%;margin-top:4px;">'
+                    f'<div style="background:#2ecc71;height:100%;width:{pct2}%;border-radius:4px;transition:width 0.15s;"></div>'
+                    f'</div>',
+                    unsafe_allow_html=True,
+                )
+            else:
+                st.markdown("**Radio 2** &nbsp; --")
+    _audio_level_fragment()
+
 # Placeholder for validation errors (will be filled in later)
 validation_error_placeholder = st.empty()
 

src/auracast/server/multicast_server.py

@@ -594,6 +594,20 @@ async def get_status():
 
     return status
 
+@app.get("/audio_level")
+async def get_audio_level():
+    """Return current RMS audio levels for primary radio (lightweight, for polling)."""
+    if multicaster1 is None:
+        return {"levels": []}
+    return {"levels": multicaster1.get_audio_levels()}
+
+@app.get("/audio_level2")
+async def get_audio_level2():
+    """Return current RMS audio levels for secondary radio (lightweight, for polling)."""
+    if multicaster2 is None:
+        return {"levels": []}
+    return {"levels": multicaster2.get_audio_levels()}
+
 async def _autostart_from_settings():
     settings1 = load_stream_settings() or {}
     settings2 = load_stream_settings2() or {}