Source code for timeside.plugins.analyzer.spectrogram

# -*- coding: utf-8 -*-
#
# Copyright (c) 2013 Paul Brossier <piem@piem.org>

# This file is part of TimeSide.

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Author: Paul Brossier <piem@piem.org>
from __future__ import division
from timeside.core import implements, interfacedoc
from timeside.core.analyzer import Analyzer
from timeside.core.api import IAnalyzer
from timeside.core.preprocessors import downmix_to_mono, frames_adapter
from timeside.core.tools.buffering import BufferTable
from timeside.core.tools.parameters import store_parameters, Int, HasTraits

import numpy as np


[docs]class Spectrogram(Analyzer): """ Spectrogram image builder with an extensible buffer based on tables Parameters ---------- input_blocksize : int, optional Blocksize of the input signal, default to 2048 input_stepsize : str, optional The second parameter, default to half blocksize. fft_size : int, optional The size of the fft, default to blocksize. Examples -------- >>> import timeside >>> from timeside.core import get_processor >>> from timeside.core.tools.test_samples import samples >>> audio_source = samples['sweep.wav'] >>> decoder = get_processor('file_decoder')(uri=audio_source) >>> spectrogram = get_processor('spectrogram_analyzer')(input_blocksize=2048, input_stepsize=1024) >>> pipe = (decoder | spectrogram) >>> pipe.run() >>> 'spectrogram_analyzer' in spectrogram.results.keys() True >>> result = spectrogram.results['spectrogram_analyzer'] >>> result.data.shape (344, 1025) import timeside from timeside.core import get_processor from timeside.core.tools.test_samples import samples audio_source = samples['sweep.wav'] decoder = get_processor('file_decoder')(uri=audio_source) spectrogram = get_processor('spectrogram_analyzer')(input_blocksize=2048, input_stepsize=1024) pipe = (decoder | spectrogram) pipe.run() res = spectrogram.results['spectrogram_analyzer'] res.render() """ implements(IAnalyzer) _schema = {"type": "object", "properties": { "fft_size": {"type": "integer"}, "input_blocksize": {"type": "integer"}, "input_stepsize": {"type": "integer"} } } # Define Parameters class _Param(HasTraits): fft_size = Int() input_blocksize = Int() input_stepsize = Int() @store_parameters def __init__(self, input_blocksize=2048, input_stepsize=None, fft_size=None): super(Spectrogram, self).__init__() self.input_blocksize = input_blocksize if input_stepsize: self.input_stepsize = input_stepsize else: self.input_stepsize = input_blocksize // 2 if not fft_size: self.fft_size = input_blocksize else: self.fft_size = fft_size self.values = []
[docs] @interfacedoc def setup(self, channels=None, samplerate=None, blocksize=None, totalframes=None): super(Spectrogram, self).setup(channels, samplerate, blocksize, totalframes)
[docs] @staticmethod @interfacedoc def id(): return "spectrogram_analyzer"
[docs] @staticmethod @interfacedoc def name(): return "Spectrogram (python)"
[docs] @staticmethod @interfacedoc def version(): return "1.0"
[docs] @staticmethod @interfacedoc def unit(): return ""
[docs] @downmix_to_mono @frames_adapter def process(self, frames, eod=False): self.values.append(np.abs(np.fft.rfft(frames, self.fft_size))) return frames, eod
[docs] def post_process(self): spectrogram = self.new_result(data_mode='value', time_mode='framewise') spectrogram.parameters = {'fft_size': self.fft_size} # spectrogram.data_object.value = self.values['spectrogram'] spectrogram.data_object.value = self.values nb_freq = spectrogram.data_object.value.shape[1] spectrogram.data_object.y_value = (np.arange(0, nb_freq) * self.samplerate() / self.fft_size) self.add_result(spectrogram)
# Generate Grapher for Spectrogram analyzer from timeside.core.grapher import DisplayAnalyzer DisplayLinearSpectrogram = DisplayAnalyzer.create( analyzer=Spectrogram, result_id='spectrogram_analyzer', grapher_id='spectrogram', grapher_name='Linear Spectrogram', grapher_version='1.0', staging=False) if __name__ == "__main__": import doctest import timeside doctest.testmod(timeside.plugins.analyzer.spectrogram, verbose=True)