You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 

122 lines
3.6 KiB

#!/usr/bin/env python3
# Render image to Oscilloscope XY vector audio
#
# https://pypi.org/project/svgpathtools/
# https://dood.al/oscilloscope/
#
# ----------------------------------------------------------------------------
# Copyright (c) 2024 Thomas Buck (thomas@xythobuz.de)
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# See <http://www.gnu.org/licenses/>.
# ----------------------------------------------------------------------------
import sys
import wave
from svgpathtools import svg2paths
samplerate = 44100 #192000
volume_percent = 70
path_steps = 10
default_duration = 5.0
default_outfile = "out.wav"
def read_image(filename):
paths, attributes = svg2paths(filename)
path = paths[0]
if len(paths) > 1:
print("WARNING: multiple paths in file. will just draw first one.")
print("paths={} segments={}".format(len(paths), len(path)))
points = [[path[0].start.real, path[0].start.imag]]
p_min = [points[0][0], points[0][1]]
p_max = [points[0][0], points[0][1]]
for segment in path:
p = [segment.end.real, segment.end.imag]
for i in range(0, 2):
if p[i] < p_min[i]:
p_min[i] = p[i]
if p[i] > p_max[i]:
p_max[i] = p[i]
points.append(p)
print("min={} max={}".format(p_min, p_max))
data = bytearray()
def add_point(p):
for i in range(0, 2):
v = p[i]
v -= p_min[i]
v /= p_max[i] - p_min[i]
if i == 1:
v = 1 - v
c = int((v * 2 - 1) * (32767 / 100 * volume_percent))
data.extend(c.to_bytes(2, byteorder="little", signed=True))
def interpolate(p1, p2, step):
p = []
for i in range(0, 2):
diff = p2[i] - p1[i]
v = p1[i] + diff * step
p.append(v)
return p
for n in range(0, len(points) - 1):
p1 = points[n]
p2 = points[n + 1]
for step in range(0, path_steps):
p = interpolate(p1, p2, step / path_steps)
add_point(p)
add_point(points[len(points) - 1])
return data
def write_waveform(data, filename):
with wave.open(filename, "w") as f:
f.setnchannels(2)
f.setsampwidth(2)
f.setframerate(samplerate)
f.writeframes(data)
def main():
if len(sys.argv) <= 1:
print("Usage:")
print("\t" + sys.argv[0] + " image.png [out.wav] [seconds]")
sys.exit(1)
if len(sys.argv) == 3:
duration = float(sys.argv[2])
outfile = default_outfile
if len(sys.argv) >= 4:
duration = float(sys.argv[2])
outfile = sys.argv[3]
else:
duration = default_duration
outfile = default_outfile
wave = read_image(sys.argv[1])
samplecount = int(len(wave) / 2 / 2) # stereo, int16
drawrate = samplerate / samplecount
drawcount = drawrate * duration
print("len={} samples={} drawrate={:.2f} count={:.2f}".format(len(wave), samplecount, drawrate, drawcount))
data = bytearray()
for n in range(0, int(drawcount)):
data.extend(wave)
print("len={}".format(len(data)))
write_waveform(bytes(data), outfile)
if __name__ == "__main__":
main()