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      1 #!/usr/bin/python
      2 
      3 # Copyright (C) 2012 The Android Open Source Project
      4 #
      5 # Licensed under the Apache License, Version 2.0 (the "License");
      6 # you may not use this file except in compliance with the License.
      7 # You may obtain a copy of the License at
      8 #
      9 #       http://www.apache.org/licenses/LICENSE-2.0
     10 #
     11 # Unless required by applicable law or agreed to in writing, software
     12 # distributed under the License is distributed on an "AS IS" BASIS,
     13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14 # See the License for the specific language governing permissions and
     15 # limitations under the License.
     16 
     17 from consts import *
     18 import numpy as np
     19 import scipy as sp
     20 import scipy.fftpack as fft
     21 import matplotlib.pyplot as plt
     22 import sys
     23 sys.path.append(sys.path[0])
     24 import calc_delay
     25 
     26 # check if amplitude of DUT's playback
     27 #  lies in the given error boundary
     28 # input: host record
     29 #        sampling rate
     30 #        low frequency in Hz,
     31 #        high frequency in Hz,
     32 #        allowed error in negative side for pass in %,
     33 #        allowed error ih positive side for pass
     34 # output: min value in negative side, normalized to 1.0
     35 #         max value in positive side
     36 #         calculated freq spectrum in amplittude
     37 
     38 def do_check_spectrum_playback(hostData, samplingRate, fLow, fHigh, margainLow, margainHigh):
     39     # reduce FFT resolution to have averaging effects
     40     N = 512 if (len(hostData) > 512) else len(hostData)
     41     iLow = N * fLow / samplingRate + 1 # 1 for DC
     42     if iLow > (N / 2 - 1):
     43         iLow = (N / 2 - 1)
     44     iHigh = N * fHigh / samplingRate + 1 # 1 for DC
     45     if iHigh > (N / 2 + 1):
     46         iHigh = N / 2 + 1
     47     print fLow, iLow, fHigh, iHigh, samplingRate
     48 
     49     Phh, freqs = plt.psd(hostData, NFFT=N, Fs=samplingRate, Fc=0, detrend=plt.mlab.detrend_none,\
     50         window=plt.mlab.window_hanning, noverlap=0, pad_to=None, sides='onesided',\
     51         scale_by_freq=False)
     52     print len(Phh)
     53     print "Phh", abs(Phh[iLow:iHigh])
     54     spectrum = np.sqrt(abs(Phh[iLow:iHigh]))
     55     spectrumMean = np.mean(spectrum)
     56     spectrum = spectrum / spectrumMean
     57     print "Mean ", spectrumMean
     58     print "Normalized spectrum", spectrum
     59     positiveMax = abs(max(spectrum))
     60     negativeMin = abs(min(spectrum))
     61     passFail = True if (positiveMax < (margainHigh / 100.0 + 1.0)) and\
     62         ((1.0 - negativeMin) < margainLow / 100.0) else False
     63     spectrumResult = np.zeros(len(spectrum), dtype=np.int16)
     64     for i in range(len(spectrum)):
     65         spectrumResult[i] = spectrum[i] * 1024 # make fixed point
     66     print "positiveMax", positiveMax, "negativeMin", negativeMin
     67     return (passFail, negativeMin, positiveMax, spectrumResult)
     68 
     69 def check_spectrum_playback(inputData, inputTypes):
     70     output = []
     71     outputData = []
     72     outputTypes = []
     73     # basic sanity check
     74     inputError = False
     75     if (inputTypes[0] != TYPE_MONO):
     76         inputError = True
     77     if (inputTypes[1] != TYPE_I64):
     78         inputError = True
     79     if (inputTypes[2] != TYPE_I64):
     80         inputError = True
     81     if (inputTypes[3] != TYPE_I64):
     82         inputError = True
     83     if (inputTypes[4] != TYPE_DOUBLE):
     84         inputError = True
     85     if (inputTypes[5] != TYPE_DOUBLE):
     86         inputError = True
     87     if inputError:
     88         output.append(RESULT_ERROR)
     89         output.append(outputData)
     90         output.append(outputTypes)
     91         return output
     92     hostData = inputData[0]
     93     samplingRate = inputData[1]
     94     fLow = inputData[2]
     95     fHigh = inputData[3]
     96     margainLow = inputData[4]
     97     margainHigh = inputData[5]
     98     (passFail, minError, maxError, Spectrum) = do_check_spectrum_playback(hostData, \
     99         samplingRate, fLow, fHigh, margainLow, margainHigh)
    100 
    101     if passFail:
    102         output.append(RESULT_PASS)
    103     else:
    104         output.append(RESULT_OK)
    105     outputData.append(minError)
    106     outputTypes.append(TYPE_DOUBLE)
    107     outputData.append(maxError)
    108     outputTypes.append(TYPE_DOUBLE)
    109     outputData.append(Spectrum)
    110     outputTypes.append(TYPE_MONO)
    111     output.append(outputData)
    112     output.append(outputTypes)
    113     return output
    114 
    115 # test code
    116 if __name__=="__main__":
    117     sys.path.append(sys.path[0])
    118     mod = __import__("gen_random")
    119     peakAmpl = 10000
    120     durationInMSec = 1000
    121     samplingRate = 44100
    122     fLow = 500
    123     fHigh = 15000
    124     data = getattr(mod, "do_gen_random")(peakAmpl, durationInMSec, samplingRate, fHigh,\
    125         stereo=False)
    126     print len(data)
    127     (passFail, minVal, maxVal, amp) = do_check_spectrum_playback(data, samplingRate, fLow,\
    128         fHigh, 1.0, 1.0)
    129     plt.plot(amp)
    130     plt.show()
    131