WAV audio file handling in SciPy - Cheat Sheet & Quick Revision

Recall & Review

beginner

What Python library and function do you use to read WAV audio files?

You use the scipy.io.wavfile.read function from the scipy library to read WAV audio files.

beginner

What two pieces of information does scipy.io.wavfile.read return when reading a WAV file?

It returns the sample rate (number of samples per second) and the audio data as a NumPy array.

beginner

How do you write audio data back to a WAV file using scipy?

Use scipy.io.wavfile.write(filename, rate, data) where filename is the output file name, rate is the sample rate, and data is the audio data array.

intermediate

What data type is the audio data returned by scipy.io.wavfile.read?

The audio data is a NumPy array, usually with integer types like int16 for 16-bit audio.

beginner

Why is the sample rate important when working with WAV files?

The sample rate tells you how many audio samples are recorded per second. It affects the playback speed and quality of the audio.

Which function reads a WAV file in scipy?

A scipy.io.wavfile.read

B scipy.io.wavfile.load

C scipy.audio.readwav

D scipy.soundfile.read

The correct function to read WAV files in scipy is scipy.io.wavfile.read.

What does the sample rate represent in a WAV file?

A Number of samples per second

B Number of audio channels

C Length of the audio in seconds

D Bit depth of the audio

Sample rate is the number of audio samples recorded per second.

What data type is typically used for 16-bit WAV audio data in scipy?

A int8

B int16

C float32

D uint8

16-bit audio data is usually stored as int16 integers.

Which function writes audio data to a WAV file in scipy?

A scipy.io.wavfile.save

B scipy.soundfile.write

C scipy.audio.writewav

D scipy.io.wavfile.write

Use scipy.io.wavfile.write to save audio data to a WAV file.

If you want to play back a WAV file correctly, which information is essential?

A File creation date

B File size

C Sample rate

D Number of channels only

The sample rate is essential to play back the audio at the correct speed and pitch.

Explain how to read a WAV file using scipy and what information you get from it.

Think about the two outputs from the read function.

Describe the steps to save audio data back to a WAV file using scipy.

Remember the order of arguments in the write function.