""" Python interface to the C-language codec2 library. """ # -*- coding: utf-8 -*- # pylint: disable=invalid-name, line-too-long, c-extension-no-member # pylint: disable=import-outside-toplevel, attribute-defined-outside-init import ctypes from ctypes import * import hashlib import glob import os import sys from enum import Enum from threading import Lock import codec2_filter_coeff import numpy as np import structlog log = structlog.get_logger("codec2") # Enum for codec2 modes class FREEDV_MODE(Enum): """ Enumeration for codec2 modes and names """ signalling = 19 signalling_ack = 20 datac0 = 14 datac1 = 10 datac3 = 12 datac4 = 18 datac13 = 19 datac14 = 20 data_ofdm_500 = 21500 data_ofdm_2438 = 2124381 #data_qam_2438 = 2124382 #qam16c2 = 22 class FREEDV_MODE_USED_SLOTS(Enum): """ Enumeration for codec2 used slots """ sig0 = [False, False, True, False, False] sig1 = [False, False, True, False, False] datac0 = [False, False, True, False, False] datac1 = [False, True, True, True, False] datac3 = [False, False, True, False, False] datac4 = [False, False, True, False, False] datac13 = [False, False, True, False, False] datac14 = [False, False, True, False, False] data_ofdm_500 = [False, False, True, False, False] data_ofdm_2438 = [True, True, True, True, True] data_qam_2438 = [True, True, True, True, True] qam16c2 = [True, True, True, True, True] # Function for returning the mode value def freedv_get_mode_value_by_name(mode: str) -> int: """ Get the codec2 mode by entering its string Args: mode: String representation of the codec2 mode. Returns: int """ return FREEDV_MODE[mode.lower()].value # Function for returning the mode name def freedv_get_mode_name_by_value(mode: int) -> str: """ Get the codec2 mode name as string Args: mode: Integer value of the codec2 mode. Returns: string """ return FREEDV_MODE(mode).name # Get the directory of the current script file script_dir = os.path.dirname(os.path.abspath(__file__)) sys.path.append(script_dir) # Use script_dir to construct the paths for file search if sys.platform == "linux": files = glob.glob(os.path.join(script_dir, "**/*libcodec2*"), recursive=True) #files.append(os.path.join(script_dir, "libcodec2.so")) elif sys.platform == "darwin": if hasattr(sys, "_MEIPASS"): files = glob.glob(os.path.join(getattr(sys, "_MEIPASS"), '**/*libcodec2*'), recursive=True) else: files = glob.glob(os.path.join(script_dir, "**/*libcodec2*.dylib"), recursive=True) elif sys.platform in ["win32", "win64"]: files = glob.glob(os.path.join(script_dir, "**\\*libcodec2*.dll"), recursive=True) else: files = [] api = None for file in files: try: api = ctypes.CDLL(file) log.info("[C2 ] Libcodec2 loaded", path=file) break except OSError as err: pass #log.info("[C2 ] Error: Libcodec2 found but not loaded", path=file, e=err) # Quit module if codec2 cant be loaded if api is None or "api" not in locals(): log.critical("[C2 ] Error: Libcodec2 not loaded - Exiting") sys.exit(1) #log.info("[C2 ] Libcodec2 loaded...", path=file) # ctypes function init # api.freedv_set_tuning_range.restype = ctypes.c_int # api.freedv_set_tuning_range.argype = [ctypes.c_void_p, ctypes.c_float, ctypes.c_float] api.freedv_open.argype = [ctypes.c_int] # type: ignore api.freedv_open.restype = ctypes.c_void_p api.freedv_set_sync.argype = [ctypes.c_void_p, ctypes.c_int] # type: ignore api.freedv_set_sync.restype = ctypes.c_void_p api.freedv_open_advanced.argtype = [ctypes.c_int, ctypes.c_void_p] # type: ignore api.freedv_open_advanced.restype = ctypes.c_void_p api.freedv_get_bits_per_modem_frame.argtype = [ctypes.c_void_p] # type: ignore api.freedv_get_bits_per_modem_frame.restype = ctypes.c_int api.freedv_get_modem_extended_stats.argtype = [ctypes.c_void_p, ctypes.c_void_p] api.freedv_get_modem_extended_stats.restype = ctypes.c_int api.freedv_nin.argtype = [ctypes.c_void_p] # type: ignore api.freedv_nin.restype = ctypes.c_int api.freedv_rawdatarx.argtype = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p] # type: ignore api.freedv_rawdatarx.restype = ctypes.c_int api.freedv_rawdatatx.argtype = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p] # type: ignore api.freedv_rawdatatx.restype = ctypes.c_int api.freedv_rawdatapostambletx.argtype = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p] # type: ignore api.freedv_rawdatapostambletx.restype = ctypes.c_int api.freedv_rawdatapreambletx.argtype = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p] # type: ignore api.freedv_rawdatapreambletx.restype = ctypes.c_int api.freedv_get_n_max_modem_samples.argtype = [ctypes.c_void_p] # type: ignore api.freedv_get_n_max_modem_samples.restype = ctypes.c_int api.freedv_set_frames_per_burst.argtype = [ctypes.c_void_p, ctypes.c_int] # type: ignore api.freedv_set_frames_per_burst.restype = ctypes.c_void_p api.freedv_get_rx_status.argtype = [ctypes.c_void_p] # type: ignore api.freedv_get_rx_status.restype = ctypes.c_int api.freedv_get_modem_stats.argtype = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p] # type: ignore api.freedv_get_modem_stats.restype = ctypes.c_int api.freedv_get_n_tx_postamble_modem_samples.argtype = [ctypes.c_void_p] # type: ignore api.freedv_get_n_tx_postamble_modem_samples.restype = ctypes.c_int api.freedv_get_n_tx_preamble_modem_samples.argtype = [ctypes.c_void_p] # type: ignore api.freedv_get_n_tx_preamble_modem_samples.restype = ctypes.c_int api.freedv_get_n_tx_modem_samples.argtype = [ctypes.c_void_p] # type: ignore api.freedv_get_n_tx_modem_samples.restype = ctypes.c_int api.freedv_get_n_max_modem_samples.argtype = [ctypes.c_void_p] # type: ignore api.freedv_get_n_max_modem_samples.restype = ctypes.c_int api.freedv_ofdm_print_info.argtype = [ctypes.c_void_p] # type: ignore api.freedv_ofdm_print_info.restype = ctypes.c_void_p api.FREEDV_FS_8000 = 8000 # type: ignore # ------- MODEM STATS STRUCTURES MODEM_STATS_NC_MAX = 50 + 1 * 2 MODEM_STATS_NR_MAX = 320 * 2 MODEM_STATS_ET_MAX = 8 MODEM_STATS_EYE_IND_MAX = 160 MODEM_STATS_NSPEC = 512 MODEM_STATS_MAX_F_HZ = 4000 MODEM_STATS_MAX_F_EST = 4 class MODEMSTATS(ctypes.Structure): """Modem statistics structure""" _fields_ = [ ("Nc", ctypes.c_int), ("snr_est", ctypes.c_float), ("rx_symbols", (ctypes.c_float * MODEM_STATS_NR_MAX) * MODEM_STATS_NC_MAX), ("nr", ctypes.c_int), ("sync", ctypes.c_int), ("foff", ctypes.c_float), ("rx_timing", ctypes.c_float), ("clock_offset", ctypes.c_float), ("sync_metric", ctypes.c_float), ("pre", ctypes.c_int), ("post", ctypes.c_int), ("uw_fails", ctypes.c_int), ("rx_eye", (ctypes.c_float * MODEM_STATS_ET_MAX) * MODEM_STATS_EYE_IND_MAX), ("neyetr", ctypes.c_int), # How many eye traces are plotted ("neyesamp", ctypes.c_int), # How many samples in the eye diagram ("f_est", (ctypes.c_float * MODEM_STATS_MAX_F_EST)), ("fft_buf", (ctypes.c_float * MODEM_STATS_NSPEC * 2)), ("fft_cfg", ctypes.c_void_p) ] # Return code flags for freedv_get_rx_status() function api.FREEDV_RX_TRIAL_SYNC = 0x1 # type: ignore # demodulator has trial sync api.FREEDV_RX_SYNC = 0x2 # type: ignore # demodulator has sync api.FREEDV_RX_BITS = 0x4 # type: ignore # data bits have been returned api.FREEDV_RX_BIT_ERRORS = 0x8 # type: ignore # FEC may not have corrected all bit errors (not all parity checks OK) api.rx_sync_flags_to_text = [ # type: ignore "----", "---T", "--S-", "--ST", "-B--", "-B-T", "-BS-", "-BST", "E---", "E--T", "E-S-", "E-ST", "EB--", "EB-T", "EBS-", "EBST", ] # Audio buffer --------------------------------------------------------- class audio_buffer: """ Thread-safe audio buffer, which fits the needs of codec2 made by David Rowe, VK5DGR """ # A buffer of int16 samples, using a fixed length numpy array self.buffer for storage # self.nbuffer is the current number of samples in the buffer def __init__(self, size): log.debug("[C2 ] Creating audio buffer", size=size) self.size = size self.buffer = np.zeros(size, dtype=np.int16) self.nbuffer = 0 self.mutex = Lock() def push(self, samples): """ Push new data to buffer Args: samples: Returns: Nothing """ self.mutex.acquire() # Add samples at the end of the buffer assert self.nbuffer + len(samples) <= self.size self.buffer[self.nbuffer : self.nbuffer + len(samples)] = samples self.nbuffer += len(samples) self.mutex.release() def pop(self, size): """ get data from buffer in size of NIN Args: size: Returns: Nothing """ self.mutex.acquire() # Remove samples from the start of the buffer self.nbuffer -= size self.buffer[: self.nbuffer] = self.buffer[size : size + self.nbuffer] assert self.nbuffer >= 0 self.mutex.release() # Resampler --------------------------------------------------------- # Oversampling rate api.FDMDV_OS_48 = 6 # type: ignore # Number of oversampling taps at 48kHz api.FDMDV_OS_TAPS_48K = 48 # type: ignore # Number of oversampling filter taps at 8kHz api.FDMDV_OS_TAPS_48_8K = api.FDMDV_OS_TAPS_48K // api.FDMDV_OS_48 # type: ignore api.fdmdv_8_to_48_short.argtype = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_int] # type: ignore api.fdmdv_48_to_8_short.argtype = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_int] # type: ignore class resampler: """ Re-sampler class """ # Re-sample an array of variable length, we just store the filter memories here MEM8 = api.FDMDV_OS_TAPS_48_8K MEM48 = api.FDMDV_OS_TAPS_48K def __init__(self): log.debug("[C2 ] Create 48<->8 kHz resampler") self.filter_mem8 = np.zeros(self.MEM8, dtype=np.int16) self.filter_mem48 = np.zeros(self.MEM48) def resample48_to_8(self, in48): """ Audio resampler integration from codec2 Downsample audio from 48000Hz to 8000Hz Args: in48: input data as np.int16 Returns: Downsampled 8000Hz data as np.int16 """ assert in48.dtype == np.int16 # Length of input vector must be an integer multiple of api.FDMDV_OS_48 assert len(in48) % api.FDMDV_OS_48 == 0 # type: ignore # Concatenate filter memory and input samples in48_mem = np.zeros(self.MEM48 + len(in48), dtype=np.int16) in48_mem[: self.MEM48] = self.filter_mem48 in48_mem[self.MEM48 :] = in48 # In C: pin48=&in48_mem[MEM48] pin48 = ctypes.byref(np.ctypeslib.as_ctypes(in48_mem), 2 * self.MEM48) n8 = int(len(in48) / api.FDMDV_OS_48) # type: ignore out8 = np.zeros(n8, dtype=np.int16) api.fdmdv_48_to_8_short(out8.ctypes, pin48, n8) # type: ignore # Store memory for next time self.filter_mem48 = in48_mem[: self.MEM48] return out8 def resample8_to_48(self, in8): """ Audio resampler integration from codec2 Re-sample audio from 8000Hz to 48000Hz Args: in8: input data as np.int16 Returns: 48000Hz audio as np.int16 """ assert in8.dtype == np.int16 # Concatenate filter memory and input samples in8_mem = np.zeros(self.MEM8 + len(in8), dtype=np.int16) in8_mem[: self.MEM8] = self.filter_mem8 in8_mem[self.MEM8 :] = in8 # In C: pin8=&in8_mem[MEM8] pin8 = ctypes.byref(np.ctypeslib.as_ctypes(in8_mem), 2 * self.MEM8) out48 = np.zeros(api.FDMDV_OS_48 * len(in8), dtype=np.int16) # type: ignore api.fdmdv_8_to_48_short(out48.ctypes, pin8, len(in8)) # type: ignore # Store memory for next time self.filter_mem8 = in8_mem[: self.MEM8] return out48 def open_instance(mode: int) -> ctypes.c_void_p: data_custom = 21 if mode in [FREEDV_MODE.data_ofdm_500.value, FREEDV_MODE.data_ofdm_2438.value]: #if mode in [FREEDV_MODE.data_ofdm_500.value, FREEDV_MODE.data_ofdm_2438.value, FREEDV_MODE.data_qam_2438]: custom_params = ofdm_configurations[mode] return ctypes.cast( api.freedv_open_advanced( data_custom, ctypes.byref(custom_params), ), ctypes.c_void_p, ) else: if mode not in [data_custom]: return ctypes.cast(api.freedv_open(mode), ctypes.c_void_p) def get_bytes_per_frame(mode: int) -> int: """ Provide bytes per frame information for accessing from data handler :param mode: Codec2 mode to query :type mode: int or str :return: Bytes per frame of the supplied codec2 data mode :rtype: int """ freedv = open_instance(mode) # TODO add close session # get number of bytes per frame for mode return int(api.freedv_get_bits_per_modem_frame(freedv) / 8) MAX_UW_BITS = 64#192 class OFDM_CONFIG(ctypes.Structure): _fields_ = [ ("tx_centre", ctypes.c_float), # TX Centre Audio Frequency ("rx_centre", ctypes.c_float), # RX Centre Audio Frequency ("fs", ctypes.c_float), # Sample Frequency ("rs", ctypes.c_float), # Symbol Rate ("ts", ctypes.c_float), # Symbol duration ("tcp", ctypes.c_float), # Cyclic Prefix duration ("timing_mx_thresh", ctypes.c_float), # Threshold for timing metrics ("nc", ctypes.c_int), # Number of carriers ("ns", ctypes.c_int), # Number of Symbol frames ("np", ctypes.c_int), # Number of freedata_server frames per packet ("bps", ctypes.c_int), # Bits per Symbol ("txtbits", ctypes.c_int), # Number of auxiliary data bits ("nuwbits", ctypes.c_int), # Number of unique word bits ("bad_uw_errors", ctypes.c_int), # Threshold for bad unique word detection ("ftwindowwidth", ctypes.c_int), # Filter window width ("edge_pilots", ctypes.c_int), # Edge pilots configuration ("state_machine", ctypes.c_char_p), # Name of sync state machine used ("codename", ctypes.c_char_p), # LDPC codename ("tx_uw", ctypes.c_uint8 * MAX_UW_BITS), # User defined unique word ("amp_est_mode", ctypes.c_int), # Amplitude estimator algorithm mode ("tx_bpf_en", ctypes.c_bool), # TX BPF enable flag ("rx_bpf_en", ctypes.c_bool), # RX BPF enable flag ("tx_bpf_proto", ctypes.POINTER(ctypes.c_float)), # low pass prototype for complex BPF ("tx_bpf_proto_n", ctypes.c_int), # number of taps in low pass prototype ("foff_limiter", ctypes.c_bool), # Frequency offset limiter enable flag ("amp_scale", ctypes.c_float), # Amplitude scale factor ("clip_gain1", ctypes.c_float), # Pre-clipping gain ("clip_gain2", ctypes.c_float), # Post-clipping gain ("clip_en", ctypes.c_bool), # Clipping enable flag ("mode", ctypes.c_char * 16), # OFDM mode in string form ("data_mode", ctypes.c_char_p), # Data mode ("streaming", "burst", etc.) ("fmin", ctypes.c_float), # Minimum frequency for tuning range ("fmax", ctypes.c_float), # Maximum frequency for tuning range ] class FREEDV_ADVANCED(ctypes.Structure): """Advanced structure for fsk and ofdm modes""" _fields_ = [ ("interleave_frames", ctypes.c_int), ("M", ctypes.c_int), ("Rs", ctypes.c_int), ("Fs", ctypes.c_int), ("first_tone", ctypes.c_int), ("tone_spacing", ctypes.c_int), ("codename", ctypes.c_char_p), ("config", ctypes.POINTER(OFDM_CONFIG)) ] api.freedv_open_advanced.argtypes = [ctypes.c_int, ctypes.POINTER(FREEDV_ADVANCED)] api.freedv_open_advanced.restype = ctypes.c_void_p def create_default_ofdm_config(): ofdm_default_config = OFDM_CONFIG( tx_centre=1500.0, rx_centre=1500.0, fs=8000.0, rs=62.5, ts=0.016, tcp=0.006, timing_mx_thresh=0.10, nc=9, ns=5, np=29, bps=2, txtbits=0, nuwbits=40, bad_uw_errors=10, ftwindowwidth=80, edge_pilots=False, state_machine="data".encode('utf-8'), codename="H_1024_2048_4f".encode('utf-8'), tx_uw=(c_uint8 * MAX_UW_BITS)(*([0] * MAX_UW_BITS)), amp_est_mode=1, tx_bpf_en=False, rx_bpf_en=False, tx_bpf_proto=codec2_filter_coeff.testFilter, tx_bpf_proto_n=int(ctypes.sizeof(codec2_filter_coeff.testFilter) / ctypes.sizeof(ctypes.c_float)), foff_limiter=False, amp_scale=300E3, clip_gain1=2.2, clip_gain2=0.8, clip_en=False, mode="CUSTOM".encode('utf-8'), data_mode="streaming".encode('utf-8'), fmin=-50.0, fmax=50.0, ) return FREEDV_ADVANCED( interleave_frames = 0, M = 2, Rs = 100, Fs = 8000, first_tone = 1000, tone_spacing = 200, codename = "H_256_512_4".encode("utf-8"), config = ctypes.pointer(ofdm_default_config), ) def create_tx_uw(nuwbits, uw_sequence): """ Creates a tx_uw ctypes array filled with the uw_sequence up to nuwbits. If uw_sequence is shorter than nuwbits, the rest of the array is filled with zeros. :param nuwbits: The number of bits for the tx_uw array, should not exceed MAX_UW_BITS. :param uw_sequence: List of integers representing the unique word sequence. :return: A ctypes array representing the tx_uw. """ # Ensure nuwbits does not exceed MAX_UW_BITS if nuwbits > MAX_UW_BITS: raise ValueError(f"nuwbits exceeds MAX_UW_BITS: {MAX_UW_BITS}") tx_uw_array = (ctypes.c_uint8 * MAX_UW_BITS)(*([0] * MAX_UW_BITS)) for i in range(min(len(uw_sequence), MAX_UW_BITS)): tx_uw_array[i] = uw_sequence[i] return tx_uw_array # ---------------- OFDM 500 Hz Bandwidth ---------------# data_ofdm_500_config = create_default_ofdm_config() data_ofdm_500_config.config.contents.ns = 5 data_ofdm_500_config.config.contents.np = 32 data_ofdm_500_config.config.contents.tcp = 0.006 data_ofdm_500_config.config.contents.ts = 0.016 data_ofdm_500_config.config.contents.rs = 1.0 / data_ofdm_500_config.config.contents.ts data_ofdm_500_config.config.contents.nc = 8 data_ofdm_500_config.config.contents.nuwbits = 40 data_ofdm_500_config.config.contents.timing_mx_thresh = 0.10 data_ofdm_500_config.config.contents.bad_uw_errors = 10 data_ofdm_500_config.config.contents.codename = "H_4096_8192_3d".encode('utf-8') data_ofdm_500_config.config.contents.amp_scale = 145E3 data_ofdm_500_config.config.contents.tx_uw = create_tx_uw(40, [0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1]) # ---------------- OFDM 2438 Hz Bandwidth 16200,9720 ---------------# data_ofdm_2438_config = create_default_ofdm_config() data_ofdm_2438_config.config.contents.ns = 5 data_ofdm_2438_config.config.contents.np = 52 data_ofdm_2438_config.config.contents.tcp = 0.004 data_ofdm_2438_config.config.contents.ts = 0.016 data_ofdm_2438_config.config.contents.rs = 1.0 / data_ofdm_2438_config.config.contents.ts data_ofdm_2438_config.config.contents.nc = 39 data_ofdm_2438_config.config.contents.nuwbits = 24 data_ofdm_2438_config.config.contents.timing_mx_thresh = 0.10 data_ofdm_2438_config.config.contents.bad_uw_errors = 8 data_ofdm_2438_config.config.contents.amp_est_mode = 0 data_ofdm_2438_config.config.contents.amp_scale = 106E3 data_ofdm_2438_config.config.contents.codename = "H_16200_9720".encode('utf-8') data_ofdm_2438_config.config.contents.clip_gain1 = 3.3 data_ofdm_2438_config.config.contents.clip_gain2 = 0.8 data_ofdm_2438_config.config.contents.timing_mx_thresh = 0.10 data_ofdm_2438_config.config.contents.tx_uw = create_tx_uw(24, [1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1]) data_ofdm_2438_config.config.contents.tx_bpf_en = True data_ofdm_2438_config.config.contents.tx_bpf_proto = codec2_filter_coeff.generate_filter_coefficients(8000, 2500, 100) data_ofdm_2438_config.config.contents.tx_bpf_proto_n = 100 # ---------------- QAM 2438 Hz Bandwidth ---------------# """ data_qam_2438_config = create_default_ofdm_config() data_qam_2438_config.config.contents.bps = 4 data_qam_2438_config.config.contents.ns = 5 data_qam_2438_config.config.contents.np = 26 data_qam_2438_config.config.contents.tcp = 0.005 data_qam_2438_config.config.contents.ts = 0.018 data_qam_2438_config.config.contents.rs = 1.0 / data_qam_2438_config.config.contents.ts data_qam_2438_config.config.contents.nc = 39 data_qam_2438_config.config.contents.nuwbits = 162 data_qam_2438_config.config.contents.timing_mx_thresh = 0.10 data_qam_2438_config.config.contents.bad_uw_errors = 50 data_qam_2438_config.config.contents.amp_est_mode = 0 data_qam_2438_config.config.contents.amp_scale = 145E3 data_qam_2438_config.config.contents.codename = b"H_16200_9720" data_qam_2438_config.config.contents.clip_gain1 = 2.7 data_qam_2438_config.config.contents.clip_gain2 = 0.8 data_qam_2438_config.config.contents.timing_mx_thresh = 0.10 data_qam_2438_config.config.contents.tx_uw = create_tx_uw(162, [1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0]) """ ofdm_configurations = { FREEDV_MODE.data_ofdm_500.value: data_ofdm_500_config, FREEDV_MODE.data_ofdm_2438.value: data_ofdm_2438_config, #FREEDV_MODE.data_qam_2438.value: data_qam_2438_config }