From 507e3b9c1cfa86c5292d01c892ecdd4c59572d16 Mon Sep 17 00:00:00 2001
From: Pete Shadbolt <pete.shadbolt@gmail.com>
Date: Thu, 15 Jan 2015 14:35:59 +0000
Subject: [PATCH] Simplify
---
spectrogram.py | 27 +++++++++++----------------
1 file changed, 11 insertions(+), 16 deletions(-)
diff --git a/spectrogram.py b/spectrogram.py
index 3e11427..cc42382 100644
--- a/spectrogram.py
+++ b/spectrogram.py
@@ -3,31 +3,26 @@ import numpy as np
import matplotlib.image as mpimg
import wave
from array import array
-from progressbar import ProgressBar
-
-def write_column(output_file, pixels, rescale=.1):
- """ Write a single column of sound """
- curve = np.fft.ifft(pixels, len(pixels)*2).real
- curve = np.array((curve-np.average(curve))*rescale, dtype=int)
- data = array("h", curve).tostring()
- output_file.writeframes(data)
def make_wav(image_filename):
""" Make a WAV file having a spectrogram resembling an image """
+ # Load image
image = mpimg.imread(image_filename)
image = np.sum(image, axis = 2).T[:, ::-1]
- image = image**2
+ image = image**3 # ???
+ w, h = image.shape
+
+ # Fourier transform, normalize, remove DC bias
+ data = np.fft.irfft(image, h*2, axis=1).reshape((w*h*2))
+ data -= np.average(data)
+ data *= (2**15.-1)/np.amax(data)
+ data = array("h", np.int_(data)).tostring()
+ # Write to disk
output_file = wave.open(image_filename+".wav", "w")
output_file.setparams((1, 2, 44100, 0, "NONE", "not compressed"))
-
- pb = ProgressBar().start()
- n = float(len(image))
- for index, column in enumerate(image):
- write_column(output_file, column)
- pb.update(index*100/n)
-
+ output_file.writeframes(data)
output_file.close()
print "Wrote %s.wav" % image_filename