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I want to generate random numbers within a certain range (1 to 26) using a .wav file with only static noise.

The results need to be repeatable.

Is there any service/program/method of accomplishing this in Windows 7?

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1  
What do you want to do with the random numbers? The answer to this question affects which method will be best to do this. – jmetz Aug 1 '12 at 14:29
    
First of all, do you know any programming languages? I assume not but that doesn't change the fact that random generated numbers that are repeatable are not random at all. That said, you may consider hashing the file with MD5 and use the hash as a seed. That will guarantee that the seed is unique to that sound snipped can reproduce predictable sequence of numbers. However, this is NOT random. – anber Feb 7 '14 at 5:54
    
@anber Yes, I have experience from a couple programming languages. From what you wrote, I will keep that in mind. Thanks! ;) – zeldarulez Feb 8 '14 at 5:34
up vote 6 down vote accepted

Try Python's scipy module,

import scipy.io.wavfile as sio

data = sio.read(FILENAME)
data = data[1].astype('float')
data -= data.min()
data *= 25.0*data.max()
data += 1

The data is now a vector and can be saved or used for further processing etc.

If for example you just want to save the output as a csv (comma separated values) file, you could then use

import csv
fout = open('output.csv', 'w')
wrt = csv.writer(fout)
wrt.writerow(data)
fout.close()
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i unfortunatly dont program/know python. How could i use this snippit of code? – zeldarulez Jul 31 '12 at 23:01
3  
@zeldarulez: As long as you can think logically, Python is one of the easiest programming languages to learn. – Ignacio Vazquez-Abrams Jul 31 '12 at 23:11
    
@zeldarulez - what do you want to do with the random numbers? – jmetz Aug 1 '12 at 14:12
    
i would like to use the use the random numbers to create a one-time pad key. I know about random.org, but i want to use a method to create it myself – zeldarulez Aug 1 '12 at 16:33
    
@IgnacioVazquez-Abrams learning a new language will be ok ;) – zeldarulez Aug 1 '12 at 16:39

If the file is PCM-encoded then you can use Python's wave module to read the samples in the file, and then fold the values into the range.

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4  
The wave module reads the data as a string - I would recommend using scipy.io.wavfile instead as I posted in my answer - it makes the data much more manageable for the subsequent rescaling. – jmetz Jul 31 '12 at 21:41

I have created true random number file using AM radio waves or what is popular called white noise. I've done it in linux, so if you want that follow these steps. 1. use your radio that has AM. 2. put frequency somewhere between radio channels - you should get white noise from radio waves and other magnetic interference... 3. use linux distro (debian/redhat based) - I have used Ubuntu. 4. Install "sox" (bundle) application, which has small app called "rec" that you will use 5. after you installed sox, place your microphone to the speakers so they can record "white noise" and use command:

rec -c 1 -r 8000 -t wav -e signed-integer randomWAVfile

in short: -c 1 (you are using one channel) -r 8000 (sampling of 8000 Hz) -t wav (format file as wav) -e signed-integer (and reads 16 bit at the same time) randomWAVfile - (file name - by your personal preference)

You will have file with random noise that is "formated" as wav file (it holds wav header of 14bits - if I am not mistaken)

to strip down header and "remove" potential duplicates use this program written in C by Rick Van Reinn

It is not a big issue, but be aware that castings in this program is not correct and your gcc will start to complain

Source code link: Openfortress source code

and by pushing down file through the program:

cat randomWAVfile | ./noise-filter > randomBits

You will get TRNG file.

I have leaned that by using this link. the only thing the guy who created original tutorial were using ancient versions of linux that operated with OSS (open sound sys) and not alsa.

Original post: Openfortress original link

Cheers

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Please read the question again carefully. Your answer does not answer the original question. OP said "The results need to be repeatable." – DavidPostill Feb 22 at 23:05
    
Sorry David, I was browsing something and haven't red question carefully. My apology. – dovla091 Feb 23 at 16:46

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