Commit 5225c753 authored by Jan Kiene's avatar Jan Kiene
Browse files

add wav file support to cutting of test vectors

parent 5aff87b6

tests/create_short_testvectors.py

+3 −3
Original line number Diff line number Diff line
@@ -52,13 +52,13 @@ def create_short_testvectors(): 
    for fs in ['48', '32', '16']:

        in_file = f"{TEST_VECTOR_DIR}/stvFOA{fs}c.wav"

        cut_gain = "1.0"

        cut_file = f"{TEST_VECTOR_DIR}/stvFOA{fs}c_cut.pcm"

        cut_file = f"{TEST_VECTOR_DIR}/stvFOA{fs}c_cut.wav"

        cut_samples(in_file, cut_file, NUM_CHANNELS, fs + "000", CUT_FROM, CUT_LEN, cut_gain)

        cut_gain = "16.0"

        cut_file = f"{TEST_VECTOR_DIR}/stvFOA{fs}c_cut_{cut_gain}.pcm"

        cut_file = f"{TEST_VECTOR_DIR}/stvFOA{fs}c_cut_{cut_gain}.wav"

        cut_samples(in_file, cut_file, NUM_CHANNELS, fs + "000", CUT_FROM, CUT_LEN, cut_gain)

        cut_gain = ".004"

        cut_file = f"{TEST_VECTOR_DIR}/stvFOA{fs}c_cut_{cut_gain}.pcm"

        cut_file = f"{TEST_VECTOR_DIR}/stvFOA{fs}c_cut_{cut_gain}.wav"

        cut_samples(in_file, cut_file, NUM_CHANNELS, fs + "000", CUT_FROM, CUT_LEN, cut_gain)

tests/cut_pcm.py

+22 −35
Original line number Diff line number Diff line
@@ -47,6 +47,13 @@ gain: optional gain value to apply to the copied samples 


import sys

import platform

import numpy as np

from pathlib import Path



HERE = Path(__file__).parent.resolve()

SCRIPTS_DIR = str(HERE.joinpath("../scripts").resolve())

sys.path.append(SCRIPTS_DIR)

from pyaudio3dtools import audiofile





def usage():
@@ -56,7 +63,7 @@ def usage(): 


def cut_samples(in_file, out_file, num_channels, sample_rate, start, duration, gain="1.0"):

    """

    Function to cut samples from a 16-bit PCM file.

    Function to cut samples from an audio file (wav or pcm)

    """



    # check for python >= 3.7
@@ -64,45 +71,25 @@ def cut_samples(in_file, out_file, num_channels, sample_rate, start, duration, g 
        sys.exit("This script is written for Python >= 3.7. Found: " + platform.python_version())



    # all input parameters are strings - convert some

    num_ch = int(num_channels)

    fs = int(sample_rate)

    start_sec = float(start)

    dur_sec = float(duration)

    gain_f = float(gain)



    with open(in_file, "rb") as fid_in:

        fid_in.seek(0, 2)

        num_in_samples = fid_in.tell() / 2

        num_in_samples_ch = num_in_samples / num_ch

    s, fs = audiofile.readfile(in_file, num_channels, fs, outdtype="float")



    num_in_samples = s.shape[0]

    num_samples_to_skip = int(start_sec * fs)

        dur_samples = dur_sec * fs

        if num_samples_to_skip + dur_samples > num_in_samples_ch:

    dur_samples = int(dur_sec * fs)

    if num_samples_to_skip + dur_samples > num_in_samples:

        sys.exit(

            f"requested too many samples ({num_samples_to_skip}+{dur_samples})"

                + f" - input is too short ({num_in_samples_ch})"

            + f" - input is too short ({num_in_samples})"

        )

        num_bytes_to_skip = num_samples_to_skip * num_ch * 2

        num_bytes_to_copy = dur_samples * num_ch * 2

        fid_in.seek(num_bytes_to_skip, 0)

        num_clip = 0

        with open(out_file, "wb") as fid_out:

            bytes_written = 0

            while bytes_written < num_bytes_to_copy:

                data = fid_in.read(2)

                val = int.from_bytes(data, byteorder="little", signed=True)

                val = int(val * gain_f)

                if val > 32767:

                    val = 32767

                    num_clip += 1

                if val < -32768:

                    val = -32768

                    num_clip += 1

                data = val.to_bytes(2, byteorder="little", signed=True)

                written = fid_out.write(data)

                assert written == 2, f"Error writing data: {written} != {2}"

                bytes_written += 2

        if num_clip:

            print(f"{num_clip} output samples have been clipped.")



    s_out = s[num_samples_to_skip:num_samples_to_skip + dur_samples, :] * gain_f



    audiofile.writefile(out_file, s_out, fs)

    



def main(argv):