Codec2 encode and decode

This commit is contained in:
Mark Qvist 2024-06-04 02:56:23 +02:00
parent 3fc67ceb2b
commit 11cfc56bd0

View File

@ -0,0 +1,129 @@
import os
import io
import math
import time
import struct
import numpy as np
import RNS
import LXMF
if RNS.vendor.platformutils.is_android():
import pyogg
from pydub import AudioSegment
else:
import sbapp.pyogg as pyogg
from sbapp.pydub import AudioSegment
codec2_modes = {
# LXMF.AM_CODEC2_450PWB: ???, # No bindings
# LXMF.AM_CODEC2_450: ???, # No bindings
LXMF.AM_CODEC2_700C: 700,
LXMF.AM_CODEC2_1200: 1200,
LXMF.AM_CODEC2_1300: 1300,
LXMF.AM_CODEC2_1400: 1400,
LXMF.AM_CODEC2_1600: 1600,
LXMF.AM_CODEC2_2400: 2400,
LXMF.AM_CODEC2_3200: 3200,
}
def samples_from_ogg(file_path=None):
if file_path != None and os.path.isfile(file_path):
opus_file = pyogg.OpusFile(file_path)
audio = AudioSegment(
bytes(opus_file.as_array()),
frame_rate=opus_file.frequency,
sample_width=opus_file.bytes_per_sample,
channels=opus_file.channels)
audio = audio.split_to_mono()[0]
audio = audio.apply_gain(-audio.max_dBFS)
audio = audio.set_frame_rate(8000)
audio = audio.set_sample_width(2)
return audio.get_array_of_samples()
def samples_to_ogg(samples=None, file_path=None):
if file_path != None and samples != None:
pcm_data = io.BytesIO(samples)
channels = 1; samples_per_second = 8000; bytes_per_sample = 2
opus_buffered_encoder = pyogg.OpusBufferedEncoder()
opus_buffered_encoder.set_application("audio")
opus_buffered_encoder.set_sampling_frequency(samples_per_second)
opus_buffered_encoder.set_channels(channels)
opus_buffered_encoder.set_frame_size(20) # milliseconds
ogg_opus_writer = pyogg.OggOpusWriter(file_path, opus_buffered_encoder)
frame_duration = 0.1
frame_size = int(frame_duration * samples_per_second)
bytes_per_frame = frame_size*bytes_per_sample
while True:
pcm = pcm_data.read(bytes_per_frame)
if len(pcm) == 0:
break
ogg_opus_writer.write(memoryview(bytearray(pcm)))
ogg_opus_writer.close()
def samples_to_wav(samples=None, file_path=None):
if samples != None and file_path != None:
import wave
with wave.open(file_path, "wb") as wf:
wf.setnchannels(1)
wf.setsampwidth(2)
wf.setframerate(8000)
wf.writeframes(samples)
return True
# Samples must be 8KHz, 16-bit, 1 channel
def encode_codec2(samples, mode):
ap_start = time.time()
import pycodec2
if not mode in codec2_modes:
return None
c2 = pycodec2.Codec2(codec2_modes[mode])
SPF = c2.samples_per_frame()
PACKET_SIZE = SPF * 2 # 16-bit samples
STRUCT_FORMAT = '{}h'.format(SPF)
N_FRAMES = math.floor(len(samples)/SPF)
frames = np.array(samples[0:N_FRAMES*SPF], dtype=np.int16)
encoded = b""
for pi in range(0, N_FRAMES):
pstart = pi*SPF
pend = (pi+1)*SPF
frame = frames[pstart:pend]
encoded_packet = c2.encode(frame)
encoded += encoded_packet
ap_duration = time.time() - ap_start
RNS.log("Codec2 encoding complete in "+RNS.prettytime(ap_duration)+", bytes out: "+str(len(encoded)), RNS.LOG_DEBUG)
return encoded
def decode_codec2(encoded_bytes, mode):
ap_start = time.time()
import pycodec2
if not mode in codec2_modes:
return None
c2 = pycodec2.Codec2(codec2_modes[mode])
SPF = c2.samples_per_frame()
BPF = c2.bytes_per_frame()
STRUCT_FORMAT = '{}h'.format(SPF)
N_FRAMES = math.floor(len(encoded_bytes)/BPF)
decoded = b""
for pi in range(0, N_FRAMES):
pstart = pi*BPF
pend = (pi+1)*BPF
encoded_packet = encoded_bytes[pstart:pend]
decoded_frame = c2.decode(encoded_packet)
decoded += struct.pack(STRUCT_FORMAT, *decoded_frame)
ap_duration = time.time() - ap_start
RNS.log("Codec2 decoding complete in "+RNS.prettytime(ap_duration)+", samples out: "+str(len(decoded)), RNS.LOG_DEBUG)
return decoded