diff --git a/extras/python/audio2mozzi.py b/extras/python/audio2mozzi.py new file mode 100755 index 000000000..fe1ae5205 --- /dev/null +++ b/extras/python/audio2mozzi.py @@ -0,0 +1,167 @@ +#!/usr/bin/env python3 +""" +For converting raw audio files to Mozzi table + +To generate waveforms using Audacity: +Set the project rate to the size of the wavetable you wish to create, which must +be a power of two (eg. 8192), and set the selection format +(beneath the editing window) to samples. Then you can generate +and save 1 second of a waveform and it will fit your table +length. + +To convert samples using Audacity: +For a recorded audio sample, set the project rate to the +MOZZI_AUDIO_RATE (16384 in the current version). +Samples can be any length, as long as they fit in your Arduino. +Save by exporting with the format set to "Other uncompressed formats", +"Header: RAW(headerless)" and choose the encoding you prefer (Signed 8/16/32-bit PCM or 32-bit Float). + +Alternative to convert samples via CLI using sox (http://sox.sourceforge.net/): +sox -b <8/16/32> -c 1 -e -r 16384 + +Now use the file you just exported, as the "input_file" to convert and +set the other parameters according to what you chose for conversion. +""" + +import array +import math +import random +import sys +import textwrap +from argparse import ArgumentParser +from pathlib import Path + + +def float2mozzi(args): + input_path = args.input_file.expanduser() + output_path = ( + args.output_file.expanduser() + if args.output_file is not None + else input_path.with_suffix(".h") + ) + + with input_path.open("rb") as fin, output_path.open("w") as fout: + print(f"opened {input_path}") + num_input_values = int( + input_path.stat().st_size / (args.input_bits / 8) + ) # Adjust for number format (table at top of https://docs.python.org/3/library/array.html) + + array_type = "" + if args.input_bits == 8: + array_type = "b" + elif args.input_bits == 16: + array_type = "h" + elif args.input_bits == 32: + array_type = "f" if args.input_encoding == "float" else "i" + + valuesfromfile = array.array(array_type) + try: + valuesfromfile.fromfile(fin, num_input_values) + except EOFError: + pass + in_values = valuesfromfile.tolist() + + tablename = ( + args.table_name + if args.table_name is not None + else output_path.stem.replace("-", "_").upper() + ) + + fout.write(f"#ifndef {tablename}_H_\n") + fout.write(f"#define {tablename}_H_\n\n") + fout.write("#include \n") + fout.write('#include "mozzi_pgmspace.h"\n\n') + fout.write(f"#define {tablename}_NUM_CELLS {len(in_values)}\n") + fout.write(f"#define {tablename}_SAMPLERATE {args.sample_rate}\n\n") + + table = f"CONSTTABLE_STORAGE(int{args.output_bits}_t) {tablename}_DATA [] = {{" + max_output_value = 2 << (args.output_bits - 2) # Halved because signed + out_values = [] + for value in in_values: + cnt_33 = 0 + out_values.append( + math.trunc((value * max_output_value) + 0.5) + if args.input_encoding == "float" + else value + ) + # Mega2560 boards won't upload if there is 33, 33, 33 in the array, so dither the 3rd 33 if there is one + if value == 33: + cnt_33 += 1 + if cnt_33 == 3: + out_values.append(random.choice((32, 34))) + cnt_33 = 0 + else: + cnt_33 = 0 + if args.make_symmetrical: + value_to_remove = -max_output_value - 1 + if value_to_remove in out_values: + in_min = value_to_remove + in_max = max_output_value + out_max = max_output_value + out_min = -max_output_value + out_values = (((value - in_min) * (out_max - out_min) / (in_max - in_min) + out_min) for value in out_values) + + table += ", ".join(map(str, out_values)) + table += "};" + table = textwrap.fill(table, 80) + fout.write(table) + fout.write("\n\n") + fout.write(f"#endif /* {tablename}_H_ */\n") + print(f"wrote {table} to {output_path}") + + return 0 + + +if __name__ == "__main__": + parser = ArgumentParser( + description="Script for converting a raw audio file to a Mozzi table", + ) + parser.add_argument( + "-e", + "--input-encoding", + choices=("float", "int"), + default="int", + help="Input encoding", + ) + parser.add_argument( + "--input-bits", + type=int, + choices=(8, 16, 32), + default=8, + help="Number of bits for the INPUT encoding", + ) + parser.add_argument( + "--output-bits", + type=int, + choices=(8, 16, 32), + default=8, + help="Number of bits for each element of the OUTPUT table", + ) + parser.add_argument("input_file", type=Path, help="Path to the input file") + parser.add_argument( + "-o", + "--output-file", + type=Path, + help="Path to the output file. It will be input_file.h if not provided", + ) + parser.add_argument( + "-t", + "--table-name", + type=str, + help="Name of the output table. If not provided, the name of the output will be used", + ) + parser.add_argument( + "-s", + "--sample-rate", + type=int, + default=16384, + help="Sample rate. Value of 16384 recommended", + ) + parser.add_argument( + "--make-symmetrical", + action="store_true", + help="Normalize the output between the range +/- max", + ) + + args_ = parser.parse_args() + sys.exit(float2mozzi(args_))