#!/usr/bin/env python

import os, sys, optparse

import run_local

from light9.wavepoints import simp

parser = optparse.OptionParser()

parser.add_option("-t",type="float",default=.01,

                  help="seconds per sample (default .01, .07 is smooth)")

options,args = parser.parse_args()

inpath,outpath = args

points = simp(inpath, seconds_per_average=options.t)

f = file(outpath, 'w')

for time_val in points:

    print >>f, "%s %s" % time_val

from __future__ import division

import wave, audioop

def simp(filename, seconds_per_average=0.001):

    """smaller seconds_per_average means fewer data points"""

    wavefile = wave.open(filename, 'rb')

    print "# gnuplot data for %s, seconds_per_average=%s" % \

        (filename, seconds_per_average)

    print "# %d channels, samplewidth: %d, framerate: %s, frames: %d\n# Compression type: %s (%s)" % wavefile.getparams()

    framerate = wavefile.getframerate() # frames / second

    frames_to_read = int(framerate * seconds_per_average)

    print "# frames_to_read=%s" % frames_to_read

    time_and_max = []

    values = []

    count = 0

    while 1:

        fragment = wavefile.readframes(frames_to_read)

        if not fragment:

            break

        # other possibilities:

        # m = audioop.avg(fragment, 2)

        # print count, "%s %s" % audioop.minmax(fragment, 2)

        m = audioop.rms(fragment, wavefile._framesize)

        time_and_max.append((count, m))

        values.append(m)

        count += frames_to_read

        # if count>1000000:

            # break

    # find the min and max

    min_value, max_value = min(values), max(values)

    points = [] # (secs,height)

    for count, value in time_and_max:

        points.append((count/framerate,

                       (value - min_value) / (max_value - min_value)))

    return points