To start, I know very little about Python. I am trying to convert a CSV to A wav file using a script I found in another post. Best I can tell it was written for an older version of python than the one I am using. One error I am getting is because of the version difference, I am just not sure how to correct it. The other error may be because of my ignorance with Python, but I am not sure of that.

The first error is:

Python\CVS-WAV2.py:44: DeprecationWarning: 'U' mode is deprecated for time, value in csv.reader(open(fname, 'U'), delimiter=','):

I know in Python 3 the 'U' has been replaced with newline= with either "None, '\n', '\r', or '\n\r'. After reading up on the newline function I think that "None" is the option I want.

Once I change 'U' to newlinw=None, My first error goes away but I still get the following when I run the script:

File "\Python\CVS-WAV2.py", line 43, in for time, value in csv.reader(open(fname, newline='\n'), delimiter=','): ValueError: not enough values to unpack (expected 2, got 0)

I am not sure how to resolve this error though.

#!/usr/bin/python

import wave
import struct
import sys
import csv
import numpy 
from scipy.io import wavfile
from scipy.signal import resample

def write_wav(data, filename, framerate, amplitude):
    wavfile = wave.open(filename,'w')
    nchannels = 1
    sampwidth = 2
    framerate = framerate
    nframes = len(data)
    comptype = "NONE"
    compname = "not compressed"
    wavfile.setparams((nchannels,
                        sampwidth,
                        framerate,
                        nframes,
                        comptype,
                        compname))
    frames = []
    for s in data:
        mul = int(s * amplitude)
        frames.append(struct.pack('h', mul))

    frames = ''.join(frames)
    wavfile.writeframes(frames)
    wavfile.close()
    print("%s written" %(filename)) 


if __name__ == "__main__":
    if len(sys.argv) <= 1:
        print ("You must supply a filename to generate")
        exit(-1)
    for fname in sys.argv[1:]:

        data = []
        for time, value in csv.reader(open(fname, newline=None), delimiter=','):
            try:
                data.append(float(value))#Here you can see that the time column is skipped
            except ValueError:
                pass # Just skip it


        arr = numpy.array(data)#Just organize all your samples into an array
        # Normalize data
        arr /= numpy.max(numpy.abs(data)) #Divide all your samples by the max sample value
        filename_head, extension = fname.rsplit(".", 1)        
        data_resampled = resample( arr, len(data) )
        wavfile.write('rec.wav', 2000, data_resampled) #resampling at 2khz
        print ("File written succesfully !")

Any help would be greatly appreciated!!

CodePudding user response：

There are probably empty lines in your CSV file. One way to skip over those is to use the following:

for record in csv.reader(open(fname, newline=None), delimiter=','):
    if not record:
        continue
    time, value = record