FreeDATA/test/test_rx.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Wed Dec 23 07:04:24 2020

@author: DJ2LS
"""

import argparse
import ctypes
import sys
import time

import numpy as np
import sounddevice as sd

sys.path.insert(0, "..")
from tnc import codec2


def test_rx():
    args = parse_arguments()

    if args.LIST:

        devices = sd.query_devices(device=None, kind=None)
        index = 0
        for device in devices:
            print(f"{index} {device['name']}")
            index += 1
        sd._terminate()
        sys.exit()

    N_BURSTS = args.N_BURSTS
    N_FRAMES_PER_BURST = args.N_FRAMES_PER_BURST
    AUDIO_INPUT_DEVICE = args.AUDIO_INPUT_DEVICE
    MODE = codec2.FREEDV_MODE[args.FREEDV_MODE].value
    DEBUGGING_MODE = args.DEBUGGING_MODE
    MAX_TIME = args.TIMEOUT

    # AUDIO PARAMETERS
    # v-- consider increasing if you get nread_exceptions > 0
    AUDIO_FRAMES_PER_BUFFER = 2400 * 2
    MODEM_SAMPLE_RATE = codec2.api.FREEDV_FS_8000
    AUDIO_SAMPLE_RATE_RX = 48000

    # make sure our resampler will work
    assert (AUDIO_SAMPLE_RATE_RX / MODEM_SAMPLE_RATE) == codec2.api.FDMDV_OS_48

    # check if we want to use an audio device then do an pyaudio init
    if AUDIO_INPUT_DEVICE != -1:
        # auto search for loopback devices
        if AUDIO_INPUT_DEVICE == -2:
            loopback_list = []

            devices = sd.query_devices(device=None, kind=None)

            for index, device in enumerate(devices):
                if "Loopback: PCM" in device["name"]:
                    print(index)
                    loopback_list.append(index)

            if loopback_list:
                # 0  = RX   1 = TX
                AUDIO_INPUT_DEVICE = loopback_list[0]
                print(f"loopback_list tx: {loopback_list}", file=sys.stderr)
            else:
                print("not enough audio loopback devices ready...")
                print("you should wait about 30 seconds...")

                sd._terminate()
                sys.exit()
        print(f"AUDIO INPUT DEVICE: {AUDIO_INPUT_DEVICE}", file=sys.stderr)

        # audio stream init
        stream_rx = sd.RawStream(
            channels=1,
            dtype="int16",
            device=AUDIO_INPUT_DEVICE,
            samplerate=AUDIO_SAMPLE_RATE_RX,
            blocksize=4800,
        )
        stream_rx.start()

    # ----------------------------------------------------------------
    # DATA CHANNEL INITIALISATION

    # open codec2 instance
    freedv = ctypes.cast(codec2.api.freedv_open(MODE), ctypes.c_void_p)

    # get number of bytes per frame for mode
    bytes_per_frame = int(codec2.api.freedv_get_bits_per_modem_frame(freedv) / 8)
    payload_bytes_per_frame = bytes_per_frame - 2

    n_max_modem_samples = codec2.api.freedv_get_n_max_modem_samples(freedv)
    bytes_out = ctypes.create_string_buffer(bytes_per_frame)

    codec2.api.freedv_set_frames_per_burst(freedv, N_FRAMES_PER_BURST)

    total_n_bytes = 0
    rx_total_frames = 0
    rx_frames = 0
    rx_bursts = 0
    rx_errors = 0
    nread_exceptions = 0
    timeout = time.time() + MAX_TIME
    receive = True
    audio_buffer = codec2.audio_buffer(AUDIO_FRAMES_PER_BUFFER * 2)
    resampler = codec2.resampler()

    # time meassurement
    time_start = 0
    time_end = 0

    # Copy received 48 kHz to a file.  Listen to this file with:
    #   aplay -r 48000 -f S16_LE rx48.raw
    # Corruption of this file is a good way to detect audio card issues
    frx = open("rx48.raw", mode="wb")

    # initial number of samples we need
    nin = codec2.api.freedv_nin(freedv)
    while receive and time.time() < timeout:
        if AUDIO_INPUT_DEVICE != -1:
            try:
                # data_in48k = stream_rx.read(AUDIO_FRAMES_PER_BUFFER, exception_on_overflow = True)
                data_in48k, overflowed = stream_rx.read(AUDIO_FRAMES_PER_BUFFER)
            except OSError as err:
                print(err, file=sys.stderr)
                # if str(err).find("Input overflowed") != -1:
                #    nread_exceptions += 1
                # if str(err).find("Stream closed") != -1:
                #    print("Ending...")
                #    receive = False
        else:
            data_in48k = sys.stdin.buffer.read(AUDIO_FRAMES_PER_BUFFER * 2)

        # insert samples in buffer
        x = np.frombuffer(data_in48k, dtype=np.int16)
        # print(x)
        # x = data_in48k
        x.tofile(frx)
        if len(x) != AUDIO_FRAMES_PER_BUFFER:
            receive = False
        x = resampler.resample48_to_8(x)
        audio_buffer.push(x)

        # when we have enough samples call FreeDV Rx
        while audio_buffer.nbuffer >= nin:
            # start time measurement
            time_start = time.time()
            # demodulate audio
            nbytes = codec2.api.freedv_rawdatarx(
                freedv, bytes_out, audio_buffer.buffer.ctypes
            )
            time_end = time.time()

            audio_buffer.pop(nin)

            # call me on every loop!
            nin = codec2.api.freedv_nin(freedv)

            rx_status = codec2.api.freedv_get_rx_status(freedv)
            if rx_status & codec2.api.FREEDV_RX_BIT_ERRORS:
                rx_errors = rx_errors + 1
            if DEBUGGING_MODE:
                rx_status = codec2.api.rx_sync_flags_to_text[rx_status]
                time_needed = time_end - time_start

                print(
                    f"nin: {nin:5d} rx_status: {rx_status:4s} "
                    f"naudio_buffer: {audio_buffer.nbuffer:4d} time: {time_needed:4f}",
                    file=sys.stderr,
                )

            if nbytes:
                total_n_bytes += nbytes

                if nbytes == bytes_per_frame:
                    rx_total_frames += 1
                    rx_frames += 1

                if rx_frames == N_FRAMES_PER_BURST:
                    rx_frames = 0
                    rx_bursts += 1

                if rx_bursts == N_BURSTS:
                    receive = False

        if time.time() >= timeout:
            print("TIMEOUT REACHED")

    if nread_exceptions:
        print(
            f"nread_exceptions {nread_exceptions:d} - receive audio lost! "
            "Consider increasing Pyaudio frames_per_buffer...",
            file=sys.stderr,
        )
    print(
        f"RECEIVED BURSTS: {rx_bursts} "
        f"RECEIVED FRAMES: {rx_total_frames} "
        f"RX_ERRORS: {rx_errors}",
        file=sys.stderr,
    )
    frx.close()

    # and at last check if we had an opened audio instance and close it
    if AUDIO_INPUT_DEVICE != -1:
        sd._terminate()

def parse_arguments():
    # --------------------------------------------GET PARAMETER INPUTS
    parser = argparse.ArgumentParser(description="Simons TEST TNC")
    parser.add_argument("--bursts", dest="N_BURSTS", default=1, type=int)
    parser.add_argument(
        "--framesperburst", dest="N_FRAMES_PER_BURST", default=1, type=int
    )
    parser.add_argument(
        "--mode", dest="FREEDV_MODE", type=str, choices=["datac0", "datac1", "datac3"]
    )
    parser.add_argument(
        "--audiodev",
        dest="AUDIO_INPUT_DEVICE",
        default=-1,
        type=int,
        help="audio device number to use, use -2 to automatically select a loopback device",
    )
    parser.add_argument("--debug", dest="DEBUGGING_MODE", action="store_true")
    parser.add_argument(
        "--timeout",
        dest="TIMEOUT",
        default=10,
        type=int,
        help="Timeout (seconds) before test ends",
    )
    parser.add_argument(
        "--list",
        dest="LIST",
        action="store_true",
        help="list audio devices by number and exit",
    )

    args, _ = parser.parse_known_args()
    return args


if __name__ == "__main__":
    test_rx()