Ran everything through the 'black' formatter

Reviewed-on: #2

data/sampleaudio/SOURCE

@@ -0,0 +1 @@
+https://www2.cs.uic.edu/~i101/SoundFiles/

docker-compose.yml

@@ -1,43 +0,0 @@
-version: "3"
-
-services:
-  kafka:
-    container_name: kafka
-    hostname: kafka
-    image: bitnami/kafka:latest
-    ports:
-      # Flip the ports around, external gets default.
-      - "9092:9094"
-      - "9094:9092"
-    networks:
-      - kafka-internal
-    volumes:
-      - "kafka_data:/bitnami"
-    environment:
-      # https://hub.docker.com/r/bitnami/kafka/
-      - ALLOW_PLAINTEXT_LISTENER=yes
-      - KAFKA_CFG_LISTENERS=PLAINTEXT://:9092,CONTROLLER://:9093,EXTERNAL://:9094
-      - KAFKA_CFG_ADVERTISED_LISTENERS=PLAINTEXT://kafka:9092,EXTERNAL://localhost:9094
-      - KAFKA_CFG_LISTENER_SECURITY_PROTOCOL_MAP=CONTROLLER:PLAINTEXT,EXTERNAL:PLAINTEXT,PLAINTEXT:PLAINTEXT
-      - KAFKA_CFG_AUTO_CREATE_TOPICS_ENABLE=true
-
-  kafka-ui:
-    container_name: kafka-ui
-    image: provectuslabs/kafka-ui:latest
-    ports:
-      - 8080:8080
-    networks:
-      - kafka-internal
-    environment:
-      # https://docs.kafka-ui.provectus.io/configuration/misc-configuration-properties
-      KAFKA_CLUSTERS_0_NAME: test
-      KAFKA_CLUSTERS_0_BOOTSTRAPSERVERS: kafka:9092
-    depends_on:
-      - kafka
-
-volumes:
-  kafka_data:
-    driver: local
-
-networks:
-  kafka-internal:

fileradio.py

@@ -0,0 +1,55 @@
+from streamer import Streamer, is_alive
+import subprocess
+import time
+import sys
+import os
+
+
+class FileRadio(Streamer):
+    REST_PATH = "sample"
+
+    def __init__(self, path):
+        super().__init__()
+        self.path = path
+        self.basename = os.path.basename(self.path)
+        self.name, self.ext = os.path.splitext(self.basename)
+
+    def _stream_thread(self):
+        self.playback = subprocess.Popen(
+            [
+                "/usr/bin/ffmpeg",
+                "-re",          # http://trac.ffmpeg.org/wiki/StreamingGuide#The-reflag
+                "-stream_loop", # Loop the stream -
+                "-1",           # ...indefinitely
+                "-i",
+                self.path,
+                "-c",
+                "copy",
+                "-f",
+                "rtsp",
+                self.stream_address("localhost"),
+            ],
+            stdin=subprocess.PIPE,
+            stdout=subprocess.DEVNULL,
+            stderr=subprocess.DEVNULL,
+        )
+
+        while self.run:
+            if not is_alive(self.playback):
+                print("Playback failed, aborting stream.", file=sys.stderr)
+                break
+            time.sleep(0.1)
+
+        self.run = False
+
+        self.playback.kill()
+        self.playback.wait()
+        self.playback = None
+
+
+if __name__ == "__main__":
+    fr = FileRadio("./data/sampleaudio/taunt.mp3")
+    fr.start_stream()
+
+    while True:
+        time.sleep(1)

filters.py

@@ -10,156 +10,159 @@
 import numpy, math, sys, time
 from numpy import fft
 
+
 def impulse(mask):
-	''' Convert frequency domain mask to time-domain '''
+    """Convert frequency domain mask to time-domain"""
-	# Negative side, a mirror of positive side
+    # Negative side, a mirror of positive side
-	negatives = mask[1:-1]
+    negatives = mask[1:-1]
-	negatives.reverse()
+    negatives.reverse()
-	mask = mask + negatives
+    mask = mask + negatives
-	fft_length = len(mask)
+    fft_length = len(mask)
 
-	# Convert FFT filter mask to FIR coefficients
+    # Convert FFT filter mask to FIR coefficients
-	impulse_response = fft.ifft(mask).real.tolist()
+    impulse_response = fft.ifft(mask).real.tolist()
 
-	# swap left and right sides
+    # swap left and right sides
-	left = impulse_response[:fft_length // 2]
+    left = impulse_response[: fft_length // 2]
-	right = impulse_response[fft_length // 2:]
+    right = impulse_response[fft_length // 2 :]
-	impulse_response = right + left
+    impulse_response = right + left
 
-	return impulse_response
+    return impulse_response
 
 
 def lo_mask(sample_rate, tap_count, freq, dboct):
-	''' Create a freq domain mask for a lowpass filter '''
+    """Create a freq domain mask for a lowpass filter"""
-	order = dboct / 6
+    order = dboct / 6
-	max_freq = sample_rate / 2.0
+    max_freq = sample_rate / 2.0
-	f2s = max_freq / (tap_count / 2.0)
+    f2s = max_freq / (tap_count / 2.0)
-	# Convert freq to filter step unit
+    # Convert freq to filter step unit
-	freq /= f2s
+    freq /= f2s
-	l = tap_count // 2
+    l = tap_count // 2
-	mask = []
+    mask = []
-	for f in range(0, l+1):
+    for f in range(0, l + 1):
-		H = 1.0 / ( 1 + (f / freq) ** (2 * order) ) ** 0.5
+        H = 1.0 / (1 + (f / freq) ** (2 * order)) ** 0.5
-		mask.append(H)
+        mask.append(H)
-	return mask
+    return mask
 
 
 def hi_mask(sample_rate, tap_count, freq, dboct):
-	''' Create a freq domain mask for a highpass filter '''
+    """Create a freq domain mask for a highpass filter"""
-	order = dboct / 6
+    order = dboct / 6
-	max_freq = sample_rate / 2.0
+    max_freq = sample_rate / 2.0
-	f2s = max_freq / (tap_count / 2.0)
+    f2s = max_freq / (tap_count / 2.0)
-	# Convert freq frequency to filter step unit
+    # Convert freq frequency to filter step unit
-	freq /= f2s
+    freq /= f2s
-	l = tap_count // 2
+    l = tap_count // 2
-	mask = []
+    mask = []
-	for f in range(0, l+1):
+    for f in range(0, l + 1):
-		H = 1.0 / ( 1 + (freq / (f + 0.0001)) ** (2 * order) ) ** 0.5
+        H = 1.0 / (1 + (freq / (f + 0.0001)) ** (2 * order)) ** 0.5
-		mask.append(H)
+        mask.append(H)
-	return mask
+    return mask
 
 
 def combine_masks(mask1, mask2):
-	''' Combine two filter masks '''
+    """Combine two filter masks"""
-	assert len(mask1) == len(mask2)
+    assert len(mask1) == len(mask2)
-	return [ mask1[i] * mask2[i] for i in range(0, len(mask1)) ]
+    return [mask1[i] * mask2[i] for i in range(0, len(mask1))]
 
 
 def taps(sample_rate, freq, dboct, is_highpass):
-	cutoff_octaves = 60 / dboct
+    cutoff_octaves = 60 / dboct
 
-	if is_highpass:
+    if is_highpass:
-		cutoff = freq / 2 ** cutoff_octaves
+        cutoff = freq / 2**cutoff_octaves
-	else:
+    else:
-		cutoff = freq * 2 ** cutoff_octaves
+        cutoff = freq * 2**cutoff_octaves
-		cutoff = min(cutoff, sample_rate / 2)
+        cutoff = min(cutoff, sample_rate / 2)
 
-	transition_band = abs(freq - cutoff)
+    transition_band = abs(freq - cutoff)
-	Bt = transition_band / sample_rate
+    Bt = transition_band / sample_rate
-	taps = int(60 / (22 * Bt))
+    taps = int(60 / (22 * Bt))
-	# print("Freq=%f,%f number of taps: %d" % (freq, cutoff, taps), file=sys.stderr)
+    # print("Freq=%f,%f number of taps: %d" % (freq, cutoff, taps), file=sys.stderr)
-	return taps
+    return taps
 
 
 class filter:
-	def __init__(self, sample_rate, cutoff):
+    def __init__(self, sample_rate, cutoff):
-		raise "Abstract"
+        raise "Abstract"
 
-	def feed(self, original):
+    def feed(self, original):
-		unfiltered = numpy.concatenate((self.buf, original))
+        unfiltered = numpy.concatenate((self.buf, original))
-		self.buf = unfiltered[-len(self.coefs):]
+        self.buf = unfiltered[-len(self.coefs) :]
-		filtered = numpy.convolve(unfiltered, self.coefs, mode='valid')
+        filtered = numpy.convolve(unfiltered, self.coefs, mode="valid")
-		assert len(filtered) == len(original) + 1
+        assert len(filtered) == len(original) + 1
-		return filtered[1:]
+        return filtered[1:]
 
 
 class low_pass(filter):
-	def __init__(self, sample_rate, f, dbo):
+    def __init__(self, sample_rate, f, dbo):
-		tap_count = taps(sample_rate, f, dbo, False)
+        tap_count = taps(sample_rate, f, dbo, False)
-		mask = lo_mask(sample_rate, tap_count, f, dbo)
+        mask = lo_mask(sample_rate, tap_count, f, dbo)
-		self.coefs = impulse(mask)
+        self.coefs = impulse(mask)
-		self.buf = [ 0 for n in self.coefs ]
+        self.buf = [0 for n in self.coefs]
 
 
 class high_pass(filter):
-	def __init__(self, sample_rate, f, dbo):
+    def __init__(self, sample_rate, f, dbo):
-		tap_count = taps(sample_rate, f, dbo, True)
+        tap_count = taps(sample_rate, f, dbo, True)
-		mask = hi_mask(sample_rate, tap_count, f, dbo)
+        mask = hi_mask(sample_rate, tap_count, f, dbo)
-		self.coefs = impulse(mask)
+        self.coefs = impulse(mask)
-		self.buf = [ 0 for n in self.coefs ]
+        self.buf = [0 for n in self.coefs]
 
 
 class band_pass(filter):
-	def __init__(self, sample_rate, lo, hi, dbo):
+    def __init__(self, sample_rate, lo, hi, dbo):
-		tap_count = max(taps(sample_rate, lo, dbo, True),
+        tap_count = max(
-				taps(sample_rate, hi, dbo, False))
+            taps(sample_rate, lo, dbo, True), taps(sample_rate, hi, dbo, False)
-		lomask = lo_mask(sample_rate, tap_count, hi, dbo)
+        )
-		himask = hi_mask(sample_rate, tap_count, lo, dbo)
+        lomask = lo_mask(sample_rate, tap_count, hi, dbo)
-		mask = combine_masks(lomask, himask)
+        himask = hi_mask(sample_rate, tap_count, lo, dbo)
-		self.coefs = impulse(mask)
+        mask = combine_masks(lomask, himask)
-		self.buf = [ 0 for n in self.coefs ]
+        self.coefs = impulse(mask)
+        self.buf = [0 for n in self.coefs]
 
 
 class deemphasis(filter):
-	def __init__(self, sample_rate, us, hi, final_dbo):
+    def __init__(self, sample_rate, us, hi, final_dbo):
-		# us = RC constant of the hypothetical deemphasis filter
+        # us = RC constant of the hypothetical deemphasis filter
-		us /= 1000000
+        us /= 1000000
-		# 0..lo is not deemphasized
+        # 0..lo is not deemphasized
-		lo = 1.0 / (2 * math.pi * us)
+        lo = 1.0 / (2 * math.pi * us)
-		# attenuation from lo to hi should be 10dB
+        # attenuation from lo to hi should be 10dB
-		octaves = math.log(hi / lo) / math.log(2)
+        octaves = math.log(hi / lo) / math.log(2)
-		# slope in dB/octave of deemphasis filter
+        # slope in dB/octave of deemphasis filter
-		dedbo = 10 / octaves
+        dedbo = 10 / octaves
 
-		tap_count = max(taps(sample_rate, lo, dedbo, False),
+        tap_count = max(
-				taps(sample_rate, hi, final_dbo, False))
+            taps(sample_rate, lo, dedbo, False), taps(sample_rate, hi, final_dbo, False)
+        )
 
-		# Calculate deemphasis filter
+        # Calculate deemphasis filter
-		demask = lo_mask(sample_rate, tap_count, lo, dedbo)
+        demask = lo_mask(sample_rate, tap_count, lo, dedbo)
-		# Calculate low-pass filter after deemphasis
+        # Calculate low-pass filter after deemphasis
-		fmask = lo_mask(sample_rate, tap_count, hi, final_dbo)
+        fmask = lo_mask(sample_rate, tap_count, hi, final_dbo)
 
-		mask = combine_masks(demask, fmask)
+        mask = combine_masks(demask, fmask)
-		self.coefs = impulse(mask)
+        self.coefs = impulse(mask)
-		self.buf = [ 0 for n in self.coefs ]
+        self.buf = [0 for n in self.coefs]
 
 
 class decimator(filter):
-	def __init__(self, factor):
+    def __init__(self, factor):
-		self.buf2 = []
+        self.buf2 = []
-		self.factor = int(factor)
+        self.factor = int(factor)
 
-	def feed(self, original):
+    def feed(self, original):
-		original = numpy.concatenate((self.buf2, original))
+        original = numpy.concatenate((self.buf2, original))
 
-		# Gets the last n-th sample of every n (n = factor)
+        # Gets the last n-th sample of every n (n = factor)
-		# If e.g. gets 12 samples, gets s[4] and s[9], and
+        # If e.g. gets 12 samples, gets s[4] and s[9], and
-		# stoves s[10:] to the next round
+        # stoves s[10:] to the next round
-		'''
+        """
 		decimated = [ original[ self.factor * i + self.factor - 1 ] \
 			for i in range(0, len(original) // self.factor) ]
-		'''
+		"""
-		decimated = original[(self.factor - 1)::self.factor]
+        decimated = original[(self.factor - 1) :: self.factor]
-		self.buf2 = original[:-len(original) % self.factor]
+        self.buf2 = original[: -len(original) % self.factor]
 
-		return decimated
+        return decimated

fm_demod.py

@@ -19,12 +19,24 @@ from formats import FORMATS
 
 
 parser = argparse.ArgumentParser()
-parser.add_argument('-v', '--verbose', help='Print additional informational output', action='store_true')
+parser.add_argument(
-parser.add_argument('-f', '--format', choices=list(FORMATS.keys()), help='Input sample format', required=True)
+    "-v", "--verbose", help="Print additional informational output", action="store_true"
-parser.add_argument('-s', '--sample-rate', metavar='rate', help='Source sample rate (Hz)', required=True)
+)
-parser.add_argument('-d', '--demod-rate', metavar='rate', help='Output sample rate (Hz)', required=True)
+parser.add_argument(
+    "-f",
+    "--format",
+    choices=list(FORMATS.keys()),
+    help="Input sample format",
+    required=True,
+)
+parser.add_argument(
+    "-s", "--sample-rate", metavar="rate", help="Source sample rate (Hz)", required=True
+)
+parser.add_argument(
+    "-d", "--demod-rate", metavar="rate", help="Output sample rate (Hz)", required=True
+)
 # TODO JMT: Output to file
-#parser.add_argument('-o', metavar='file', help='Specify an output file for demodulated audio. Omit for stdout or use \'-\'.')
+# parser.add_argument('-o', metavar='file', help='Specify an output file for demodulated audio. Omit for stdout or use \'-\'.')
 args = parser.parse_args()
 
 INPUT_RATE = int(prefixed.Float(args.sample_rate))
@@ -32,16 +44,19 @@ OUTPUT_RATE = int(prefixed.Float(args.demod_rate))
 DECIMATION = INPUT_RATE / OUTPUT_RATE
 
 if DECIMATION != math.floor(DECIMATION):
-	print(f'The output rate must be an integer divisor of the input rate: {INPUT_RATE}/{OUTPUT_RATE} = {DECIMATION}', file=sys.stderr)
+    print(
-	sys.exit(1)
+        f"The output rate must be an integer divisor of the input rate: {INPUT_RATE}/{OUTPUT_RATE} = {DECIMATION}",
+        file=sys.stderr,
+    )
+    sys.exit(1)
 
 FORMAT = FORMATS[args.format].numpy
 DT = np.dtype(FORMAT)
 BYTES_PER_SAMPLE = 2 * DT.itemsize
 
-MAX_DEVIATION = 200000.0 # Hz
+MAX_DEVIATION = 200000.0  # Hz
-FM_BANDWIDTH = 15000 # Hz
+FM_BANDWIDTH = 15000  # Hz
-STEREO_CARRIER = 38000 # Hz
+STEREO_CARRIER = 38000  # Hz
 DEVIATION_X_SIGNAL = 0.999 / (math.pi * MAX_DEVIATION / (INPUT_RATE / 2))
 
 pll = math.pi - random.random() * 2 * math.pi
@@ -63,137 +78,138 @@ decimate2 = filters.decimator(DECIMATION)
 lo_r = filters.deemphasis(INPUT_RATE, 75, FM_BANDWIDTH, 120)
 
 # Band-pass filter for stereo (L-R) modulated audio
-hi = filters.band_pass(INPUT_RATE,
+hi = filters.band_pass(
-	STEREO_CARRIER - FM_BANDWIDTH, STEREO_CARRIER + FM_BANDWIDTH, 120)
+    INPUT_RATE, STEREO_CARRIER - FM_BANDWIDTH, STEREO_CARRIER + FM_BANDWIDTH, 120
+)
 
 # Filter to extract pilot signal
-pilot = filters.band_pass(INPUT_RATE,
+pilot = filters.band_pass(
-	STEREO_CARRIER / 2 - 100, STEREO_CARRIER / 2 + 100, 120)
+    INPUT_RATE, STEREO_CARRIER / 2 - 100, STEREO_CARRIER / 2 + 100, 120
+)
 
 last_angle = 0.0
-remaining_data = b''
+remaining_data = b""
 
 while True:
-	# Ingest 0.1s worth of data
+    # Ingest 0.1s worth of data
-	data = sys.stdin.buffer.read((INPUT_RATE * BYTES_PER_SAMPLE) // 10)
+    data = sys.stdin.buffer.read((INPUT_RATE * BYTES_PER_SAMPLE) // 10)
-	if not data:
+    if not data:
-		break
+        break
-	# TODO JMT: Something about this is broken for BYTES_PER_SAMPLE > 1
+    # TODO JMT: Something about this is broken for BYTES_PER_SAMPLE > 1
-	#data = remaining_data + data
+    # data = remaining_data + data
 
-	if len(data) < 2 * BYTES_PER_SAMPLE:
+    if len(data) < 2 * BYTES_PER_SAMPLE:
-		remaining_data = data
+        remaining_data = data
-		continue
+        continue
 
-	# Save one sample to next batch, and the odd byte if exists
+    # Save one sample to next batch, and the odd byte if exists
-	if len(data) % 2 == 1:
+    if len(data) % 2 == 1:
-		print("Odd byte, that's odd", file=sys.stderr)
+        print("Odd byte, that's odd", file=sys.stderr)
-		remaining_data = data[-3:]
+        remaining_data = data[-3:]
-		data = data[:-1]
+        data = data[:-1]
-	else:
+    else:
-		remaining_data = data[-2:]
+        remaining_data = data[-2:]
 
-	samples = len(data) // BYTES_PER_SAMPLE
+    samples = len(data) // BYTES_PER_SAMPLE
 
-	# Find angle (phase) of I/Q pairs
+    # Find angle (phase) of I/Q pairs
-	iqdata = np.frombuffer(data, dtype=FORMAT)
+    iqdata = np.frombuffer(data, dtype=FORMAT)
 
-	if args.verbose:
+    if args.verbose:
-		print(iqdata.dtype, iqdata.shape, iqdata, file=sys.stderr)
+        print(iqdata.dtype, iqdata.shape, iqdata, file=sys.stderr)
 
-	if np.issubdtype(FORMAT, np.integer):
+    if np.issubdtype(FORMAT, np.integer):
-		iinfo = np.iinfo(FORMAT)
+        iinfo = np.iinfo(FORMAT)
-		if np.issubdtype(FORMAT, np.unsignedinteger):
+        if np.issubdtype(FORMAT, np.unsignedinteger):
-			iqdata = iqdata - (iinfo.max / 2.0)
+            iqdata = iqdata - (iinfo.max / 2.0)
-			iqdata = iqdata / (iinfo.max / 2.0)
+            iqdata = iqdata / (iinfo.max / 2.0)
-		else:
+        else:
-			iqdata = iqdata / np.float64(iinfo.max)
+            iqdata = iqdata / np.float64(iinfo.max)
-	else:
+    else:
-		iqdata = iqdata.astype(np.float64)
+        iqdata = iqdata.astype(np.float64)
 
-	if args.verbose:
+    if args.verbose:
-		print(iqdata.dtype, iqdata.shape, iqdata, file=sys.stderr)
+        print(iqdata.dtype, iqdata.shape, iqdata, file=sys.stderr)
 
-	iqdata = iqdata.view(complex)
+    iqdata = iqdata.view(complex)
-	angles = np.angle(iqdata)
+    angles = np.angle(iqdata)
 
-	# Determine phase rotation between samples
+    # Determine phase rotation between samples
-	rotations = np.ediff1d(angles)
+    rotations = np.ediff1d(angles)
 
-	# Wrap rotations >= +/-180º
+    # Wrap rotations >= +/-180º
-	rotations = (rotations + np.pi) % (2 * np.pi) - np.pi
+    rotations = (rotations + np.pi) % (2 * np.pi) - np.pi
 
-	# Convert rotations to baseband signal
+    # Convert rotations to baseband signal
-	output_raw = np.multiply(rotations, DEVIATION_X_SIGNAL)
+    output_raw = np.multiply(rotations, DEVIATION_X_SIGNAL)
-	output_raw = np.clip(output_raw, -0.999, +0.999)
+    output_raw = np.clip(output_raw, -0.999, +0.999)
 
-	# At this point, output_raw contains two audio signals:
+    # At this point, output_raw contains two audio signals:
-	# L+R (mono-compatible) and L-R (joint-stereo) modulated in AM-SC,
+    # L+R (mono-compatible) and L-R (joint-stereo) modulated in AM-SC,
-	# carrier 38kHz
+    # carrier 38kHz
 
-	# Downsample and low-pass L+R (mono) signal
+    # Downsample and low-pass L+R (mono) signal
-	output_mono = lo.feed(output_raw)
+    output_mono = lo.feed(output_raw)
-	output_mono = decimate1.feed(output_mono)
+    output_mono = decimate1.feed(output_mono)
 
-	# Filter pilot tone
+    # Filter pilot tone
-	detected_pilot = pilot.feed(output_raw)
+    detected_pilot = pilot.feed(output_raw)
 
-	# Separate ultrasonic L-R signal by high-pass filtering
+    # Separate ultrasonic L-R signal by high-pass filtering
-	output_jstereo_mod = hi.feed(output_raw)
+    output_jstereo_mod = hi.feed(output_raw)
-	output_jstereo = []
+    output_jstereo = []
 
-	# Demodulate L-R, which is AM-SC with 53kHz carrier
+    # Demodulate L-R, which is AM-SC with 53kHz carrier
-	for n in range(0, len(output_jstereo_mod)):
+    for n in range(0, len(output_jstereo_mod)):
-		# Advance carrier
+        # Advance carrier
-		pll = (pll + tau * STEREO_CARRIER / INPUT_RATE) % tau
+        pll = (pll + tau * STEREO_CARRIER / INPUT_RATE) % tau
-		# Standard demodulation
+        # Standard demodulation
-		output_jstereo.append(math.cos(pll) * output_jstereo_mod[n])
+        output_jstereo.append(math.cos(pll) * output_jstereo_mod[n])
 
-		# Detect pilot zero-crossing
+        # Detect pilot zero-crossing
-		cur_pilot = detected_pilot[n]
+        cur_pilot = detected_pilot[n]
-		zero_crossed = (cur_pilot * last_pilot) <= 0
+        zero_crossed = (cur_pilot * last_pilot) <= 0
-		last_pilot = cur_pilot
+        last_pilot = cur_pilot
-		if not zero_crossed:
+        if not zero_crossed:
-			continue
+            continue
 
-		# When pilot is at 90º or 270º, carrier should be around 180º
+        # When pilot is at 90º or 270º, carrier should be around 180º
-		ideal = math.pi
+        ideal = math.pi
-		deviation = pll - ideal
+        deviation = pll - ideal
-		if deviation > math.pi:
+        if deviation > math.pi:
-			deviation -= tau
+            deviation -= tau
-		deviation_avg = 0.99 * deviation_avg + 0.01 * deviation
+        deviation_avg = 0.99 * deviation_avg + 0.01 * deviation
-		rotation = deviation_avg - last_deviation_avg
+        rotation = deviation_avg - last_deviation_avg
-		last_deviation_avg = deviation_avg
+        last_deviation_avg = deviation_avg
 
-		if abs(deviation_avg) > math.pi / 8:
+        if abs(deviation_avg) > math.pi / 8:
-			# big phase deviation, reset PLL
+            # big phase deviation, reset PLL
-			pll = ideal
+            pll = ideal
-			pll = (pll + tau * STEREO_CARRIER / INPUT_RATE) % tau
+            pll = (pll + tau * STEREO_CARRIER / INPUT_RATE) % tau
-			deviation_avg = 0.0
+            deviation_avg = 0.0
-			last_deviation_avg = 0.0
+            last_deviation_avg = 0.0
 
-		# Translate rotation to frequency deviation
+        # Translate rotation to frequency deviation
-		STEREO_CARRIER /= (1 + (rotation * 1.05) / tau)
+        STEREO_CARRIER /= 1 + (rotation * 1.05) / tau
 
+    # Downsample, Low-pass/deemphasis demodulated L-R
+    output_jstereo = lo_r.feed(output_jstereo)
+    output_jstereo = decimate2.feed(output_jstereo)
 
-	# Downsample, Low-pass/deemphasis demodulated L-R
+    assert len(output_jstereo) == len(output_mono)
-	output_jstereo = lo_r.feed(output_jstereo)
-	output_jstereo = decimate2.feed(output_jstereo)
 
-	assert len(output_jstereo) == len(output_mono)
+    # Scale to 16-bit and divide by 2 for channel sum
+    output_mono = np.multiply(output_mono, 32767 / 2.0)
+    output_jstereo = np.multiply(output_jstereo, 32767 / 2.0)
 
-	# Scale to 16-bit and divide by 2 for channel sum
+    # Output stereo by adding or subtracting joint-stereo to mono
-	output_mono = np.multiply(output_mono, 32767 / 2.0)
+    output_left = output_mono + output_jstereo
-	output_jstereo = np.multiply(output_jstereo, 32767 / 2.0)
+    output_right = output_mono - output_jstereo
 
-	# Output stereo by adding or subtracting joint-stereo to mono
+    # Interleave L and R samples using np trickery
-	output_left = output_mono + output_jstereo
+    output = np.empty(len(output_mono) * 2, dtype=output_mono.dtype)
-	output_right = output_mono - output_jstereo
+    output[0::2] = output_left
+    output[1::2] = output_right
+    output = output.astype(int)
 
-	# Interleave L and R samples using np trickery
+    sys.stdout.buffer.write(struct.pack("<%dh" % len(output), *output))
-	output = np.empty(len(output_mono) * 2, dtype=output_mono.dtype)
-	output[0::2] = output_left
-	output[1::2] = output_right
-	output = output.astype(int)
-
-	sys.stdout.buffer.write(struct.pack('<%dh' % len(output), *output))

formats.py

@@ -2,6 +2,7 @@ import numpy as np
 from SoapySDR import *
 from dataclasses import dataclass
 
+
 @dataclass
 class FormatSpec:
     name: str
@@ -9,9 +10,10 @@ class FormatSpec:
     numpy: np.dtype
     packing: str
 
+
 FORMATS = {
-    'CU8': FormatSpec('CU8', SOAPY_SDR_CU8, np.uint8, '=%dB'),
+    "CU8": FormatSpec("CU8", SOAPY_SDR_CU8, np.uint8, "=%dB"),
-    'CS8': FormatSpec('CS8', SOAPY_SDR_CS8, np.int8, '=%db'),
+    "CS8": FormatSpec("CS8", SOAPY_SDR_CS8, np.int8, "=%db"),
-    'CS16': FormatSpec('CS16', SOAPY_SDR_CS16, np.int16, '=%dh'),
+    "CS16": FormatSpec("CS16", SOAPY_SDR_CS16, np.int16, "=%dh"),
-    'CF32': FormatSpec('CF32', SOAPY_SDR_CF32, np.float32, '=%df'),
+    "CF32": FormatSpec("CF32", SOAPY_SDR_CF32, np.float32, "=%df"),
 }

kafkalogging.py

@@ -1,64 +0,0 @@
-from kafka import KafkaProducer
-import subprocess
-import os
-
-kafka_servers = ['localhost:9092']
-producers = {}
-
-
-# Do anything that might take more than a few ms early, otherwise you hit overflow errors
-def prep_io(process, process_name=None):
-    for pipe_name,pipe in {'stdout':process.stdout, 'stderr':process.stderr}.items():
-        if pipe is None:
-            continue
-
-        if os.get_blocking(pipe.fileno()):
-            os.set_blocking(pipe.fileno(), False)
-
-        if process.pid not in producers:
-            producers[process.pid] = {}
-        if pipe_name not in producers[process.pid]:
-            producers[process.pid][pipe_name] = KafkaProducer(
-                bootstrap_servers=kafka_servers,
-                max_block_ms=200
-            )
-
-
-# Inspired by gist:
-# https://gist.github.com/krzemienski/8c7e8e76c8652984cca0da3fea5b5368
-def check_io(process, process_name=None):
-    for pipe_name,pipe in {'stdout':process.stdout, 'stderr':process.stderr}.items():
-        if pipe is None:
-            continue
-
-        topic_name = f"{process.pid if process_name is None else process_name}-{pipe_name}"
-
-        while True:
-            # The python official docs recommend using Popen.communicate() instead of reading
-            # from the pipes directly. Using Popen.communicate is a blocking call though,
-            # which would stall threads for processes producing no output.
-            output = pipe.readline()
-            if output:
-                producers[process.pid][pipe_name].send(topic_name, value=output)
-            else:
-                break
-
-        producers[process.pid][pipe_name].flush()
-
-
-
-if __name__ == '__main__':
-    import time
-
-    ping = subprocess.Popen(
-        [
-            '/usr/bin/ping',
-            '1.1.1.1',
-        ],
-        stdout=subprocess.PIPE,
-        stderr=subprocess.PIPE
-    )
-
-    while True:
-        check_io(ping, 'ping')
-        time.sleep(0.1)

mediamtx.yml

@@ -38,10 +38,10 @@ udpMaxPayloadSize: 1472
 externalAuthenticationURL:
 
 # Enable the HTTP API.
-api: no
+api: yes
 
 # Enable Prometheus-compatible metrics.
-metrics: no
+metrics: yes
 
 # Enable pprof-compatible endpoint to monitor performances.
 pprof: no

microservice.py

@@ -1,7 +1,12 @@
 #! /usr/bin/env python3
 
+import os
+import sys
+import requests
 import SoapySDR as soapy
 from radio import Radio
+from tuuube import Tuuube
+from fileradio import FileRadio
 
 from flask import Flask, jsonify
 from flasgger import Swagger
@@ -13,8 +18,30 @@ swag = Swagger(app)
 radios = {}
 
 
-@app.route('/radio/report')
+@app.route("/report")
 def report():
+    """Get streams report from the RTSP relay.
+    ---
+    responses:
+      200:
+        description: JSON with streams report.
+      400:
+        description: JSON with error message.
+    """
+    try:
+        r = requests.get("http://localhost:9997/v1/paths/list")
+        j = r.json()
+        for item in j["items"]:
+            del j["items"][item]["conf"]
+            del j["items"][item]["confName"]
+
+        return jsonify(j)
+    except Exception as e:
+        return _error_message_json(e.message), 500
+
+
+@app.route("/radio/report")
+def radio_report():
     """List radio devices available to the system.
     ---
     responses:
@@ -25,7 +52,8 @@ def report():
     devices = [dict(device) for device in soapy.Device.enumerate()]
     return jsonify(devices)
 
-@app.route('/radio/<radio>/connect')
+
+@app.route("/radio/<radio>/connect")
 def connect(radio):
     """Connect to a radio device, by driver name or serial number.
     ---
@@ -37,29 +65,29 @@ def connect(radio):
         required: true
     responses:
       200:
-        description: Successfully connected to a radio.
+        description: JSON with message successfully connected to a radio.
       400:
-        description: No radio device by that name is available.
+        description: JSON with error message No radio device by that name is available.
       500:
-        description: Failed to connect to radio.
+        description: JSON with error message failed to connect to radio.
     """
     if radio in radios:
-        return "Radio device already connected", 400
+        return _error_message_json("Radio device already connected"), 400
 
     devices = [dict(device) for device in soapy.Device.enumerate()]
     for device in devices:
         if radio in device.values():
             try:
                 radios[radio] = Radio(radio, device)
-                return "", 200
+                return jsonify("message", "successfully connected radio"), 200
             except Exception as e:
                 radios.pop(radio)
-                return str(e), 500
+                return _error_message_json(e.message), 500
-
 
     return "Radio device not found", 400
 
-@app.route('/radio/<radio>/disconnect')
+
+@app.route("/radio/<radio>/disconnect")
 def disconnect(radio):
     """Disconnect from a radio device.
     ---
@@ -79,11 +107,12 @@ def disconnect(radio):
     """
     if radio in radios:
         radios.pop(radio)
-        return "", 200
+        return jsonify("message", "succesfully disconnected radio"), 200
     else:
-        return "Radio not connected", 400
+        return _error_message_json("Radio not connected"), 400
 
-@app.route('/radio/<radio>/configure/<frequency>')
+
+@app.route("/radio/<radio>/configure/<frequency>")
 def configure(radio, frequency):
     """Tune the radio to a frequency.
     You must connect to the radio before attempting to configure it.
@@ -102,20 +131,21 @@ def configure(radio, frequency):
         required: true
     responses:
       200:
-        description: JSON
+        description: JSON with radio configuration.
       400:
         description: The specified radio is not connected.
     """
     if radio in radios:
         return jsonify(radios[radio].configure(frequency))
     else:
-        return "Radio not connected", 400
+        return _error_message_json("Radio not connected"), 400
 
-@app.route('/radio/<radio>/start')
+
+@app.route("/radio/<radio>/start")
 def start_stream(radio):
     """Start the radio stream.
     Once the stream has been started, connect to the stream at:
-    rtsp://[host]:8554/radio/[radio]/stream
+    rtsp://[host]:8554/radio/[radio]
     ---
     parameters:
       - name: radio
@@ -123,14 +153,20 @@ def start_stream(radio):
         in: path
         type: string
         required: true
+    responses:
+      200:
+        description: JSON with message successful start of radio stream.
+      400:
+        description: JSON with error message.
     """
     try:
         radios[radio].start_stream()
-        return "", 200
+        return jsonify("message", "successfully started radio stream"), 200
     except Exception as e:
-        return str(e), 400
+        return _error_message_json(e.message), 400
 
-@app.route('/radio/<radio>/end')
+
+@app.route("/radio/<radio>/end")
 def end_stream(radio):
     """Terminate the radio stream.
     ---
@@ -140,14 +176,21 @@ def end_stream(radio):
         in: path
         type: string
         required: true
+    responses:
+      200:
+        description: JSON with message successful termination of radio stream.
+      400:
+        description: JSON with error message.
     """
     try:
         radios[radio].end_stream()
-        return "", 200
+        return jsonify("message", "successfully ended radio stream"), 200
     except Exception as e:
-        return str(e), 400
+        error_message = {"error_message": e.message}
+        return _error_message_json(e.message), 400
 
-@app.route('/radio/<radio>/info')
+
+@app.route("/radio/<radio>/info")
 def radio_info(radio):
     """Get information about a radio.
     ---
@@ -159,40 +202,117 @@ def radio_info(radio):
         required: true
     responses:
       200:
-        description: JSON
+        description: JSON with radio information.
       400:
-        description: The specified radio is not connected.
+        description: JSON with error message.
     """
     try:
         return jsonify(radios[radio].get_info())
     except Exception as e:
-        return str(e), 400
+        return _error_message_json(e.message), 400
 
 
-if __name__ == '__main__':
+tubes = {}
+
+
+@app.route("/tuuube/<id>/start")
+def start_tuuube_stream(id):
+    """Start streaming from a youtube source.
+    Once the stream has been started, connect to the stream at:
+    rtsp://[host]:8554/tuuube/[id]
+    ---
+    parameters:
+      - name: id
+        description:
+          The youtube video ID. That is the part following the `watch?v=` in the URL. For example, `dQw4w9WgXcQ`.\n
+          Other good options are - \n
+          `BaW_jenozKc`, yt_dlp package test video.\n
+          `b2je8uBlgFM`, stereo audio test.\n
+          `LDU_Txk06tM`, crab rave, a commonly used audio fidelity test.\n
+          `sPT_epMLkwQ`, Kilsyth CFA major factory fire dispatch radio traffic.
+        in: path
+        type: string
+        required: true
+    responses:
+      200:
+        description: JSON with message successful start of youtube stream.
+      400:
+        description: JSON with error message.
+    """
+    if id not in tubes:
+        tubes[id] = Tuuube(id)
+
+    try:
+        tubes[id].start_stream()
+        return jsonify("message", "successfully started youtube stream"), 200
+    except Exception as e:
+        return _error_message_json(e.message), 400
+
+
+@app.route("/tuuube/<id>/end")
+def end_tuuube_stream(id):
+    """Terminate the youtube stream.
+    ---
+    parameters:
+      - name: id
+        description: The youtube video ID.
+        in: path
+        type: string
+        required: true
+    responses:
+      200:
+        description: JSON with message successful termination of youtube stream.
+      400:
+        description: JSON with error message.
+    """
+    try:
+        tubes[id].end_stream()
+        return jsonify("message", "succesfully ended youtube stream"), 200
+    except Exception as e:
+        return _error_message_json(e.message), 400
+
+
+"""
+    Helper function to return a JSON error message
+    parameters: error_message - the error message to return
+    returns: a JSON object with the error message
+    """
+
+
+def _error_message_json(error_message: str):
+    error_message = {"error_message": error_message}
+    return jsonify(error_message)
+
+
+if __name__ == "__main__":
     import subprocess
 
     rtsp_relay = subprocess.Popen(
-        [
+        ["./dependencies/mediamtx/mediamtx", "./mediamtx.yml"],
-            './dependencies/mediamtx/mediamtx',
-            './mediamtx.yml'
-        ],
         stdout=subprocess.DEVNULL,
-        stderr=subprocess.DEVNULL
+        stderr=subprocess.DEVNULL,
     )
 
-    app.run(
+    for path, _, files in os.walk("./data/sampleaudio"):
-        host='0.0.0.0',
+        for file in files:
-        threaded=True,
+            name, ext = os.path.splitext(file)
-        debug=False
+            if ext == ".mp3":
-    )
+                tubes[name] = FileRadio(f"{path}/{file}")
+                tubes[name].start_stream()
 
-    print('Stopping any currently streaming radios...')
+    app.run(host="0.0.0.0", threaded=True, debug=False)
+
+    print("Stopping any currently streaming radios...")
     for radio in radios:
-      if radios[radio].is_streaming():
+        if radios[radio].is_streaming():
-        radios[radio].end_stream()
+            radios[radio].end_stream()
     radios = None
 
-    print('Killing RTSP relay...')
+    for tube in tubes:
+        if tubes[tube].is_streaming():
+            tubes[tube].end_stream()
+    tubes = None
+
+    print("Killing RTSP relay...")
     rtsp_relay.kill()
-    rtsp_relay.wait() # Necessary?
+    rtsp_relay.wait()  # Necessary?

radio.py

@@ -7,20 +7,19 @@ import subprocess
 import struct
 from soapyhelpers import *
 from samplerates import *
-from kafkalogging import *
+from streamer import Streamer, is_alive
 
 
-class Radio:
+class Radio(Streamer):
-    FORMAT = 'CS16'
+    REST_PATH = "radio"
+    FORMAT = "CS16"
     SAMPLES = 8192
-    PORT = 8554
 
     def __init__(self, name, device_info):
+        super().__init__()
+
         self.name = name
         self.device_info = device_info
-        self.run = False
-        self.thread = None
-
         self.device = soapy.Device(device_info)
         if self.device is None:
             raise RuntimeError("Failed to connect to radio device")
@@ -34,7 +33,7 @@ class Radio:
         frequency = int(prefixed.Float(frequency))
         bandwidth = 200000
 
-        sample_rates = preferred_sample_rates(self.capabilities['rx']['sample-rates'])
+        sample_rates = preferred_sample_rates(self.capabilities["rx"]["sample-rates"])
         if len(sample_rates) == 0:
             raise RuntimeError("No suitable sample rates are available")
         self.sample_rate, self.output_rate = sample_rates[0]
@@ -47,72 +46,52 @@ class Radio:
         self.device.setGainMode(soapy.SOAPY_SDR_RX, 0, True)
 
         return {
-            'frequency': self.device.getFrequency(soapy.SOAPY_SDR_RX, 0),
+            "frequency": self.device.getFrequency(soapy.SOAPY_SDR_RX, 0),
-            'sample-rate': self.device.getSampleRate(soapy.SOAPY_SDR_RX, 0),
+            "sample-rate": self.device.getSampleRate(soapy.SOAPY_SDR_RX, 0),
-            'bandwidth': self.device.getBandwidth(soapy.SOAPY_SDR_RX, 0),
+            "bandwidth": self.device.getBandwidth(soapy.SOAPY_SDR_RX, 0),
-            'gain-mode': 'auto' if self.device.getGainMode(soapy.SOAPY_SDR_RX, 0) else 'manual',
+            "gain-mode": "auto"
+            if self.device.getGainMode(soapy.SOAPY_SDR_RX, 0)
+            else "manual",
         }
 
     def get_info(self):
         return {
-            'name': self.name,
+            "name": self.name,
-            'device': self.device_info,
+            "device": self.device_info,
-            'capabilities': self.capabilities,
+            "capabilities": self.capabilities,
-            'stream-path': self._stream_path(),
+            "stream-path": self._stream_path(),
-            'streaming': self.is_streaming(),
+            "streaming": self.is_streaming(),
         }
 
     def _get_capabilities(self):
         def get_direction_capabilities(direction):
             return {
-                'antennas': self.device.listAntennas(direction, 0),
+                "antennas": self.device.listAntennas(direction, 0),
-                'gains': self.device.listGains(direction, 0),
+                "gains": self.device.listGains(direction, 0),
-                'frequencies': self.device.listFrequencies(direction, 0),
+                "frequencies": self.device.listFrequencies(direction, 0),
-                'sample-rates': self.device.listSampleRates(direction, 0),
+                "sample-rates": self.device.listSampleRates(direction, 0),
-                'bandwidths': self.device.listBandwidths(direction, 0),
+                "bandwidths": self.device.listBandwidths(direction, 0),
-                'sensors': self.device.listSensors(direction, 0),
+                "sensors": self.device.listSensors(direction, 0),
-                'formats': self.device.getStreamFormats(direction, 0),
+                "formats": self.device.getStreamFormats(direction, 0),
             }
 
         return {
-            'rx': get_direction_capabilities(soapy.SOAPY_SDR_RX),
+            "rx": get_direction_capabilities(soapy.SOAPY_SDR_RX),
-            'tx': get_direction_capabilities(soapy.SOAPY_SDR_TX),
+            "tx": get_direction_capabilities(soapy.SOAPY_SDR_TX),
-            'clock-sources': self.device.listClockSources(),
+            "clock-sources": self.device.listClockSources(),
-            'time-sources': self.device.listTimeSources(),
+            "time-sources": self.device.listTimeSources(),
-            'register-interfaces': self.device.listRegisterInterfaces(),
+            "register-interfaces": self.device.listRegisterInterfaces(),
-            'gpios': self.device.listGPIOBanks(),
+            "gpios": self.device.listGPIOBanks(),
-            'uarts': self.device.listUARTs(),
+            "uarts": self.device.listUARTs(),
         }
 
-    def is_streaming(self):
-        return True if (self.thread and self.thread.is_alive()) else False
-
-    def start_stream(self):
-        if self.is_streaming():
-            raise RuntimeError('Stream thread is already running')
-
-        self.run = True
-        self.thread = Thread(target=self._stream_thread, daemon=True, args=())
-        self.thread.start()
-
-    def end_stream(self):
-        if self.thread is None:
-            raise RuntimeError('No stream thread to terminate')
-
-        self.run = False
-        self.thread.join()
-        self.thread = None
-
     def _stream_thread(self):
         self._init_stream()
 
-        def is_alive(subprocess):
-            return (subprocess.poll() is None)
-
         while self.run:
             # Check that the child processes are still running
             if (not is_alive(self.demod)) or (not is_alive(self.playback)):
-                print('DSP chain failed, aborting stream.', file=sys.stderr)
+                print("DSP chain failed, aborting stream.", file=sys.stderr)
                 break
 
             result = self.device.readStream(self.stream, [self.buffer], Radio.SAMPLES)
@@ -122,46 +101,63 @@ class Radio:
             elif result.ret < 0:
                 error = SoapyError(result.ret)
                 if error is not SoapyError.Timeout:
-                    print("Stream read failed, aborting stream:", error, file=sys.stderr)
+                    print(
+                        "Stream read failed, aborting stream:", error, file=sys.stderr
+                    )
                     break
                 continue
             else:
                 read_size = int(result.ret * 2)
                 self.demod.stdin.write(
-                    struct.pack(FORMATS[Radio.FORMAT].packing % read_size,
+                    struct.pack(
-                    *self.buffer[:read_size])
+                        FORMATS[Radio.FORMAT].packing % read_size,
+                        *self.buffer[:read_size],
+                    )
                 )
 
-            # handle subprocess logs
-            check_io(self.demod, f"{self.name}-demod")
-            check_io(self.playback, f"{self.name}-playback")
-
-
         self._cleanup_stream()
 
     def _init_stream(self):
         self.playback = subprocess.Popen(
             [
-                '/usr/bin/ffmpeg', '-f', 's16le', '-ar', str(self.output_rate), '-ac', '2', '-i', '-',
+                "/usr/bin/ffmpeg",
-                '-f', 'rtsp', f"rtsp://localhost{self._stream_path()}"
+                "-f",
+                "s16le",
+                "-ar",
+                str(self.output_rate),
+                "-ac",
+                "2",
+                "-i",
+                "-",
+                "-f",
+                "rtsp",
+                self.stream_address(),
             ],
             stdin=subprocess.PIPE,
-            stdout=subprocess.PIPE,
+            stdout=subprocess.DEVNULL,
-            stderr=subprocess.PIPE
+            stderr=subprocess.DEVNULL,
         )
 
         self.demod = subprocess.Popen(
-            ['/usr/bin/python3', 'fm_demod.py', '-f', 'CS16', '-s', str(self.sample_rate), '-d', str(self.output_rate)],
+            [
+                "/usr/bin/python3",
+                "fm_demod.py",
+                "-f",
+                "CS16",
+                "-s",
+                str(self.sample_rate),
+                "-d",
+                str(self.output_rate),
+            ],
             stdin=subprocess.PIPE,
             stdout=self.playback.stdin,
-            stderr=subprocess.PIPE
+            stderr=subprocess.DEVNULL,
         )
 
-        prep_io(self.demod, f"{self.name}-demod")
-        prep_io(self.playback, f"{self.name}-playback")
-
         self.buffer = np.array([0] * Radio.SAMPLES * 2, FORMATS[Radio.FORMAT].numpy)
-        self.stream = self.device.setupStream(soapy.SOAPY_SDR_RX, FORMATS[Radio.FORMAT].soapy)
+        self.stream = self.device.setupStream(
+            soapy.SOAPY_SDR_RX, FORMATS[Radio.FORMAT].soapy
+        )
         result = self.device.activateStream(self.stream)
 
         if result != 0:
@@ -185,29 +181,26 @@ class Radio:
         self.playback.wait()
         self.playback = None
 
-    def _stream_path(self):
-        return f":{Radio.PORT}/radio/{self.name}"
-
 
 """
 Quick and dirty test of the Radio class.
 """
-if __name__ == '__main__':
+if __name__ == "__main__":
     import time
 
-    sdr = Radio('demo', {'driver': 'sdrplay'})
+    sdr = Radio("demo", {"driver": "sdrplay"})
 
-    print('Configuring...')
+    print("Configuring...")
-    sdr.configure('105.5M')
+    sdr.configure("105.5M")
-    print('Configured.')
+    print("Configured.")
 
-    print('Starting stream...')
+    print("Starting stream...")
     sdr.start_stream()
-    print('Stream started.')
+    print("Stream started.")
 
     # Let the stream play for a while
     time.sleep(15)
 
-    print('Ending stream...')
+    print("Ending stream...")
     sdr.end_stream()
-    print('Stream ended.')
+    print("Stream ended.")

requirements.pip

@@ -3,3 +3,5 @@ flasgger==0.9.5
 Flask==2.2.3
 numpy==1.17.4
 prefixed==0.7.0
+PyYAML==6.0
+requests==2.22.0

samplerates.py

@@ -6,7 +6,7 @@ Sample rates stolen from:
     https://en.wikipedia.org/wiki/Sampling_(signal_processing)
 """
 supported_ouput_rates = [
-    8000,   # Telephone, P25 audio (sufficient for speech, some consonants unintelligble)
+    8000,  # Telephone, P25 audio (sufficient for speech, some consonants unintelligble)
     16000,  # Modern telephone/VoIP, good quality speech
     32000,  # FM radio
     44100,  # CD audio quality
@@ -14,9 +14,10 @@ supported_ouput_rates = [
     50000,  # Uncommon but supported
     88200,
     96000,  # DVD/Blu-ray audio
-    192000, # Too much.
+    192000,  # Too much.
 ]
 
+
 def score(pair, target_output=32000, target_ratio=10):
     """
     Heuristic for scoring input & output sample rates. The criteria are:
@@ -36,29 +37,38 @@ def score(pair, target_output=32000, target_ratio=10):
 
     ratio = pair[0] // pair[1]
 
-    return abs(pair[1] - target_output)/2500 \
+    return (
-        + max(0, target_output - pair[1])/2500 \
+        abs(pair[1] - target_output) / 2500
-        + abs(ratio - target_ratio)**0.8 \
+        + max(0, target_output - pair[1]) / 2500
-        + max(0, target_ratio - ratio)**2
+        + abs(ratio - target_ratio) ** 0.8
+        + max(0, target_ratio - ratio) ** 2
+    )
+
 
 def flatten(l):
     return [item for sublist in l for item in sublist]
 
+
 def flatten_dict(d):
-    return [(key,value) for key,rates in d.items() for value in rates]
+    return [(key, value) for key, rates in d.items() for value in rates]
+
 
 def get_pairs(input_rate):
     return [
-        (input_rate, rate)
+        (input_rate, rate) for rate in supported_ouput_rates if (input_rate % rate == 0)
-        for rate in supported_ouput_rates
-        if (input_rate % rate == 0)
     ]
 
+
 def supported_sample_rates(supported_input_rates):
     return {
-        in_rate: [out_rate for out_rate in supported_ouput_rates if in_rate % out_rate == 0]
+        in_rate: [
+            out_rate for out_rate in supported_ouput_rates if in_rate % out_rate == 0
+        ]
         for in_rate in supported_input_rates
     }
 
+
 def preferred_sample_rates(supported_input_rates):
-    return sorted(flatten_dict(supported_sample_rates(supported_input_rates)), key=score)
+    return sorted(
+        flatten_dict(supported_sample_rates(supported_input_rates)), key=score
+    )

scripts/connect.sh

@@ -1,34 +0,0 @@
-#! /bin/bash
-
-set -e
-
-
-server="localhost:5000"
-radio="sdrplay"
-frequency="105.5M"
-
-trap deinit INT
-
-deinit() {
-    curl $server/radio/$radio/end
-    curl $server/radio/$radio/disconnect
-    #kill $pid
-    killall ffplay
-    echo -n ""
-}
-
-init() {
-    curl $server/radio/$radio/connect
-    curl $server/radio/$radio/configure/$frequency
-    curl $server/radio/$radio/start
-}
-
-init
-echo "Waiting for stream to become active..."
-sleep 3
-ffplay -nodisp -hide_banner rtsp://localhost:8554/radio/sdrplay &
-pid=$!
-
-while true; do
-    sleep 1
-done

scripts/wav2mp3.sh

@@ -0,0 +1,8 @@
+#! /bin/bash
+
+for arg in "$@"; do
+    path="${arg%/*}"
+    file="${arg##*/}"
+    filename="${file%%.*}"
+    ffmpeg -i $path/$file -vn -ar 44100 -ac 2 -b:a 100k $path/$filename.mp3
+done

setup.sh

@@ -8,6 +8,10 @@ setup() {
     sudo xargs apt-get install -y < requirements.apt
     sudo pip install -r requirements.pip
 
+    # Requires yt-dlp, but a very recent version (as youtube broke their API for the pip version)
+    # https://stackoverflow.com/a/75504772
+    python3 -m pip install --force-reinstall https://github.com/yt-dlp/yt-dlp/archive/master.tar.gz
+
     # Install device driver
     ./scripts/SDRplay_RSP_API-Linux-3.07.1.run
 

soapyhelpers.py

@@ -1,6 +1,7 @@
 import SoapySDR as soapy
 from enum import IntEnum
 
+
 class SoapyError(IntEnum):
     Timeout = soapy.SOAPY_SDR_TIMEOUT
     StreamError = soapy.SOAPY_SDR_STREAM_ERROR
@@ -10,6 +11,7 @@ class SoapyError(IntEnum):
     TimeError = soapy.SOAPY_SDR_TIME_ERROR
     Underflow = soapy.SOAPY_SDR_UNDERFLOW
 
+
 class SoapyFlag(IntEnum):
     EndBurst = soapy.SOAPY_SDR_END_BURST
     HasTime = soapy.SOAPY_SDR_HAS_TIME

streamer.py

@@ -0,0 +1,51 @@
+from threading import Thread
+import yaml
+
+
+with open("mediamtx.yml", "r") as config_file:
+    MEDIASERVER_CONFIG = yaml.safe_load(config_file)
+
+
+def is_alive(subprocess):
+    return True if (subprocess and subprocess.poll() is None) else False
+
+
+class Streamer:
+    PROTOCOL = "rtsp"
+    REST_PATH = "stream"
+
+    def __init__(self):
+        self.run = False
+        self.thread = None
+        self.name = None
+
+    def stream_path(self):
+        return f"{MEDIASERVER_CONFIG['rtspAddress']}/{type(self).REST_PATH}/{self.name}"
+
+    def stream_address(self, host):
+        return f"{Streamer.PROTOCOL}://{host}{self.stream_path()}"
+
+    def is_streaming(self):
+        return True if (self.thread and self.thread.is_alive()) else False
+
+    def start_stream(self):
+        if self.is_streaming():
+            raise RuntimeError("Stream thread is already running")
+
+        self.run = True
+        self.thread = Thread(target=self._stream_thread, daemon=True, args=())
+        self.thread.start()
+
+    def end_stream(self):
+        if self.thread is None:
+            raise RuntimeError("No stream thread to terminate")
+
+        self.run = False
+        self.thread.join()
+        self.thread = None
+
+
+if __name__ == "__main__":
+    from pprint import pprint
+
+    pprint(MEDIASERVER_CONFIG)

tuuube.py

@@ -0,0 +1,92 @@
+#! /usr/bin/env python3
+
+"""
+We aren't using either the apt or the pip repositories for the youtube_dl
+as there is a known bug affecting those two versions. The youtube API has changed
+since their release, causing downloads to fail.
+Make sure you use the ./setup.sh script to obtain the latest github release of
+yt_dlp, as this version carries the latest fixes.
+"""
+# import youtube_dl
+import yt_dlp as youtube_dl
+from streamer import Streamer, is_alive
+import subprocess
+import time
+import sys
+import os
+
+
+class Tuuube(Streamer):
+    REST_PATH = "tuuube"
+
+    def __init__(self, name):
+        super().__init__()
+        self.name = name
+        self.playback = None
+
+    def source_path(self):
+        return f"/tmp/{self.name}.mp3"
+
+    def _stream_thread(self):
+        if not os.path.exists(self.source_path()) or not os.path.isfile(
+            self.source_path()
+        ):
+            ydl_opts = {
+                "format": "bestaudio/best",
+                "outtmpl": f"/tmp/{self.name}.%(ext)s", # yt_dlp will append %(ext) if not specified,
+                "postprocessors": [                     # resulting in `/tmp/file.mp3.mp3` :/
+                    {  
+                        "key": "FFmpegExtractAudio",
+                        "preferredcodec": "mp3",
+                        "preferredquality": "192",
+                    }
+                ],
+            }
+
+            try:
+                with youtube_dl.YoutubeDL(ydl_opts) as ydl:
+                    ydl.download([f"https://www.youtube.com/watch?v={self.name}"])
+            except Exception as e:
+                print(f"File sourcing failed, aborting stream. {e}", file=sys.stderr)
+                self.run = False
+                return
+
+        self.playback = subprocess.Popen(
+            [
+                "/usr/bin/ffmpeg",
+                "-re",
+                "-stream_loop",
+                "-1",
+                "-i",
+                self.source_path(),
+                "-c",
+                "copy",
+                "-f",
+                "rtsp",
+                self.stream_address("localhost"),
+            ],
+            stdin=subprocess.PIPE,
+            stdout=subprocess.DEVNULL,
+            stderr=subprocess.DEVNULL,
+        )
+
+        while self.run:
+            if not is_alive(self.playback):
+                print("Playback failed, aborting stream.", file=sys.stderr)
+                break
+            time.sleep(0.1)
+
+        self.run = False
+
+        self.playback.kill()
+        self.playback.wait()
+        self.playback = None
+
+
+if __name__ == "__main__":
+    tube = Tuuube("BaW_jenozKc")
+    tube.start_stream()
+
+    while True:
+        print(tube.is_streaming())
+        time.sleep(1)