Unable to properly increment variable and convert to .wav to .mp3

Question

I am trying to create a new file recording every time this program runs and also convert those .wav files to .mp3. When I run this, it only creates a output.wav and output0.mp3 file and then when I run it again, no further files are created. Also the output0.mp3 that was converted is 0KB and cannot be played.

I do not get an error but it seems its not grabbing the output.wav properly that was originally created. I am running Python 3.7.

import os
import sounddevice as sd
from scipy.io.wavfile import write
from pydub import AudioSegment #for converting WAV to MP3


fs = 44100  # Sample rate
seconds = 3  # Duration of recording

myrecording = sd.rec(int(seconds * fs), samplerate=fs, channels=2)
sd.wait()  # Wait until recording is finished
write('output.wav', fs, myrecording )  # Save as WAV file


#Increments file name by 1 so it writes a new file every time it runs
i = 0
while os.path.exists("output%s.wav" % i):
    i += 1

    # files for converting WAV to Mp3
    src = ("output%s.wav" % i)
    dst = ("output%s.mp3" % i)

    # convert wav to mp3
    sound = AudioSegment.from_mp3(src)
    sound.export(dst, format="wav")

writefile = open("output%s.mp3" % i, "w")

EDIT:

Updated while loop to:

#Increments file name by 1 so it writes a new file every time it runs
i = 0
while os.path.exists("output%s.wav" % i):

    # files for converting WAV to Mp3
    src = ("output%s.wav" % i)
    dst = ("output%s.mp3" % i)

    # convert wav to mp3
    sound = AudioSegment.from_mp3(src)
    sound.export(dst, format="wav")

    write("output%s.mp3" % i, "w")

    i += 1

Answer 1

SOLUTION: Updated my while loop and changed the conversion method

i = 0

while not os.path.exists("output.wav"):
    i += 1
    fs = 44100  # Sample rate
    seconds = 3  # Duration of recording

    myrecording = sd.rec(int(seconds * fs), samplerate=fs, channels=2)
    sd.wait()  # Wait until recording is finished
    write('output{0}.wav'.format(i), fs, myrecording )  # Save as WAV file
    print("recording has finished")

    datadir = str(Path(r"FilePathtoFolderWhereAudioFileIs"))
    filetopen = datadir + "/" + 'output{0}.wav'.format(i)

    sound = pydub.AudioSegment.from_wav(r"FilePathtoFolderWhereAudioFileIs""" + "\\output{0}.wav".format(i))
    sound.export(r"FilePathtoFolderWhereAudioFileIs""" + "\\output{0}.mp3".format(i), format="mp3")
    print("Converted wav to mp3")

    time.sleep(3)

Answer 2

"create a new file recording every time this program runs " - To what I understand you just need to check for existing files and get a counter to reach +1 then the last file. Once you get that just create/convert file based on that.

I am not familiar with working of sound module, but in general below should be the code structure.

## This will create new recording file called output.wav

myrecording = sd.rec(int(seconds * fs), samplerate=fs, channels=2)
sd.wait()  # Wait until recording is finished
write('output.wav', fs, myrecording )  # Save as WAV file


# Get the counter to reach the last file that has been created.
# For e.g. if last file generated was output5.wav then below loop will run 5 times
# and should change the value of i = 6.
i = 0
while os.path.exists("output%s.wav" % i):
    i += 1

# Code for creating new file using value of 'i'
# Below code is outside of while loop and will run only once,
# as 1 file needs to be created per run of the program.

src = ("output.wav")
dst = ("output%s.mp3" % i)

# convert wav to mp3
sound = AudioSegment.from_mp3(src)
sound.export(dst, format="wav")

# Not sure if this is needed.
# Check working of sound module and what does sound.export do

writefile = open("output%s.mp3" % i, "w")