create audiobuffer class

test/001_highsnr_stdio_audio/test_rx.py

@@ -101,9 +101,7 @@ rx_bursts = 0
 rx_errors = 0
 timeout = time.time() + TIMEOUT
 receive = True
-naudio_buffer_max = codec2.api.freedv_get_n_max_modem_samples(freedv)*2
-audio_buffer = np.zeros(naudio_buffer_max, dtype=np.int16)
-naudio_buffer = 0
+audio_buffer = codec2.audio_buffer(codec2.api.freedv_get_n_max_modem_samples(freedv))
 
 # initial number of samples we need
 nin = codec2.api.freedv_nin(freedv)
@@ -119,19 +117,15 @@ while receive and time.time() < timeout:
     x = np.frombuffer(data_in, dtype=np.int16)
     if len(x) == 0:
         receive = False
-    audio_buffer[naudio_buffer:naudio_buffer+len(x)] = x
-    naudio_buffer += len(x)
-    assert naudio_buffer <= naudio_buffer_max
+    audio_buffer.push(x)
     
     # when we have enough samples call FreeDV Rx
-    while naudio_buffer >= nin:
-
-        nbytes = codec2.api.freedv_rawdatarx(freedv, bytes_out, audio_buffer.ctypes) # demodulate audio
-
-        # remove old samples from buffer
-        naudio_buffer -= nin;
-        audio_buffer[:naudio_buffer] = audio_buffer[nin:nin+naudio_buffer]
+    while audio_buffer.nbuffer >= nin:
 
+         # demodulate audio
+        nbytes = codec2.api.freedv_rawdatarx(freedv, bytes_out, audio_buffer.buffer.ctypes)        
+        audio_buffer.pop(nin)
+        
         # call me on every loop!
         nin = codec2.api.freedv_nin(freedv)
        
@@ -140,8 +134,8 @@ while receive and time.time() < timeout:
             rx_errors = rx_errors + 1
         if DEBUGGING_MODE:        
           rx_status = codec2.api.rx_sync_flags_to_text[rx_status]
-          print("nin: %5d rx_status: %4s naudio_buffer: %4d len(audio_buffer): %d)" % \
-                (nin,rx_status,naudio_buffer,len(audio_buffer)), file=sys.stderr)
+          print("nin: %5d rx_status: %4s naudio_buffer: %4d" % \
+                (nin,rx_status,audio_buffer.nbuffer), file=sys.stderr)
 
         if nbytes:
             total_n_bytes = total_n_bytes + nbytes

test/codec2.py

@@ -6,6 +6,7 @@ from ctypes import *
 import sys
 import pathlib
 from enum import Enum
+import numpy as np
 
 print("loading codec2 module", file=sys.stderr)
 
@@ -19,6 +20,22 @@ class FREEDV_MODE(Enum):
 def FREEDV_GET_MODE(mode):
     return FREEDV_MODE[mode].value
 
+class audio_buffer:
+    def __init__(self, size):
+        self.size = size
+        self.buffer = np.zeros(size, dtype=np.int16)
+        self.nbuffer = 0
+    def push(self,samples):
+        self.buffer[self.nbuffer:self.nbuffer+len(samples)] = samples
+        self.nbuffer += len(samples)
+        assert self.nbuffer <= self.size
+    def nbuffer(self):
+        return self.nbuffer
+    def pop(self,size):
+        self.nbuffer -= size;
+        self.buffer[:self.nbuffer] = self.buffer[size:size+self.nbuffer]
+        assert self.nbuffer >= 0
+               
 # LOAD FREEDV
 libname = "libcodec2.so"
 api = ctypes.CDLL(libname)