Added usage notes to the README

scripts/README.md

@@ -51,3 +51,13 @@ low pass & decimate if necessary
             reset code detection counter (prohibit detecting codes for another 0.5 sec)
 
 ```
+
+## Usage
+Either
+```
+./audio-capture.sh | ./live.py
+```
+or
+```
+./audio-pipe.sh ./samples/MA-ZC.wav | ./live.py
+```

scripts/audio-capture.sh

@@ -3,6 +3,6 @@
 set -eux
 
 sample_rate="44100"
-channels="2"
+channels="1"
 
-arecord -t raw -c ${channels} -f S16_LE -r ${sample_rate}
+arecord -t raw -c ${channels} -f S16_LE -r ${sample_rate}

scripts/audio-pipe.sh

@@ -4,6 +4,6 @@ set -eux
 
 audio_file=$1
 sample_rate="44100"
-channels="2"
+channels="1"
 
-ffmpeg -i ${audio_file} -f s16le -ac ${channels} -ar ${sample_rate} -
+ffmpeg -hide_banner -loglevel error -i ${audio_file} -f s16le -ac ${channels} -ar ${sample_rate} -

scripts/live.py

@@ -3,19 +3,14 @@
 import sys
 import threading
 import numpy as np
-import signal
+import signal as sig
+from tones import TONES
+from filters import anti_alias, bandpass_filter, note
+from scipy import signal
+from scipy.signal import butter, lfilter, decimate
+
 import pyqtgraph as pg
-
-data1 = np.random.normal(size=300)
-ptr1 = 0
-
-win = pg.GraphicsLayoutWidget(show=True)
-win.setWindowTitle('pyqtgraph example: Scrolling Plots')
-
-plot = win.addPlot()
-curve = plot.plot(data1)
-
-
+from pyqtgraph.Qt import QtGui, QtWidgets, mkQApp
 
 keep_running = True
 def signal_handler(sig, frame):
@@ -23,6 +18,62 @@ def signal_handler(sig, frame):
     print('SIGINT received. Stopping...')
     keep_running = False
 
+
+class DetectorGui(QtWidgets.QMainWindow):
+    def __init__(self, *args, **kwargs):
+        super(DetectorGui, self).__init__(*args, **kwargs)
+        layout = pg.GraphicsLayoutWidget(show=True)
+        self.setCentralWidget(layout)
+        self.setWindowTitle('SELCAL Detector')
+        self.resize(1280, 800)
+
+        self.plot = layout.addPlot()
+        legend_view = layout.addViewBox()
+
+        legend = pg.LegendItem(offset=(0, 0))
+        legend.setParentItem(legend_view)
+
+        color_map = pg.colormap.get('CET-C6s')
+        colors = color_map.getLookupTable(nPts=len(TONES))
+
+        t = np.linspace(0, 500, 100)
+
+        self.tone_data = {}
+        self.tone_lines = {}
+
+        for tone,color in zip(TONES.keys(), colors):
+            self.tone_data[tone] = np.zeros(int(10000), dtype=np.float64) #np.array([], dtype=np.float64)
+            self.tone_lines[tone] = self.plot.plot(self.tone_data[tone], pen=pg.mkPen(color=color), name=tone)
+            legend.addItem(self.tone_lines[tone], tone)
+
+        self.plot.setLabel('left', 'Signal Correlation')
+        self.plot.setLabel('bottom', 'Time (samples)')
+        self.plot.showGrid(x=True, y=True)
+
+        legend_view.setFixedWidth(80)
+        layout.ci.layout.setColumnFixedWidth(1, 80)
+
+        self.show()
+
+    def set_position(self, pos):
+        pass
+
+    def push_tone(self, tone, value):
+        self.tone_data[tone] = np.roll(self.tone_data[tone], -1)
+        self.tone_data[tone][-1] = value
+        self.tone_lines[tone].setData(self.tone_data[tone])
+
+    def push_tones(self, tone, values):
+        #self.tone_data[tone] = np.append(self.tone_data[tone], values)
+
+        self.tone_data[tone] = np.roll(self.tone_data[tone], -len(values))
+        self.tone_data[tone][-len(values):] = values
+        self.tone_lines[tone].setData(self.tone_data[tone])
+
+
+mkQApp("Correlation matrix display")
+gui = DetectorGui()
+
 def read_audio_from_stdin(chunk_size, process_chunk):
     global keep_running
 
@@ -39,55 +90,43 @@ def read_audio_from_stdin(chunk_size, process_chunk):
         audio_chunk = np.frombuffer(data, dtype=np.int16)
         process_chunk(audio_chunk)
 
+sample_rate = 44100
+note_length = 0.1
+N = 256
+cumsum_convolution = np.ones(N)/N
+
+
 def process_audio_chunk(audio_chunk):
-    # Example processing: simply print the chunk
-    global data1, ptr1, curve
-    print(f"Read chunk: {len(audio_chunk)}")
+    global gui
 
-    data1[:-1] = data1[1:]  # shift data in the array one sample left
-                           # (see also: np.roll)
-    data1[-1] = len(audio_chunk)
+    data = audio_chunk
+    sample_rate = 44100
 
-    ptr1 += 1
-    curve.setData(data1)
-    curve.setPos(ptr1, 0)
+    data, sample_rate, decimation = anti_alias(data, sample_rate, 4800)
+    pure_signals = {tone:note(freq, note_length, rate=sample_rate) for tone,freq in TONES.items()}
+    correlations = {tone:np.abs(signal.correlate(data, pure, mode='same')) for tone,pure in pure_signals.items()}
+    massaged = {tone:decimate(np.convolve(correlation, cumsum_convolution, mode='valid'), 4) for tone,correlation in correlations.items()}
+
+    print('processing done')
+
+    for tone,massage in massaged.items():
+        gui.push_tones(tone, massage )
 
 
 if __name__ == '__main__':
-    signal.signal(signal.SIGINT, signal_handler)
+    sig.signal(sig.SIGINT, signal_handler)
 
     chunk_duration = 0.1 # seconds
     sample_rate = 44100
-    channels = 2
+    channels = 1
     chunk_size = int(sample_rate * chunk_duration) * channels
 
     reader_thread = threading.Thread(target=read_audio_from_stdin, args=(chunk_size, process_audio_chunk))
     reader_thread.daemon = True
     reader_thread.start()
 
+
     pg.exec()
 
     # Wait...
     reader_thread.join()
-
-
-'''
-# 1) Simplest approach -- update data in the array such that plot appears to scroll
-#    In these examples, the array size is fixed.
-p1 = win.addPlot()
-p2 = win.addPlot()
-data1 = np.random.normal(size=300)
-curve1 = p1.plot(data1)
-curve2 = p2.plot(data1)
-ptr1 = 0
-def update1():
-    global data1, ptr1
-    data1[:-1] = data1[1:]  # shift data in the array one sample left
-                            # (see also: np.roll)
-    data1[-1] = np.random.normal()
-    curve1.setData(data1)
-
-    ptr1 += 1
-    curve2.setData(data1)
-    curve2.setPos(ptr1, 0)
-'''