# -*- coding: utf-8 -*-
#
# Copyright (c) 2007-2010 Guillaume Pellerin <yomguy@parisson.com>
# Copyright (c) 2010 Olivier Guilyardi <olivier@samalyse.com>
# 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/>.
from timeside.core import implements, interfacedoc
from timeside.core.api import IGrapher
from timeside.plugins.grapher.spectrogram_log import SpectrogramLog
[docs]class SpectrogramLinear(SpectrogramLog):
"""Linear scaled spectrogram (level vs. frequency vs. time).
Adds pixels iteratively thanks to the adapter providing fixed size frame buffers."""
implements(IGrapher)
@interfacedoc
def __init__(self, width=4096, height=256, bg_color=(0, 0, 0), color_scheme='default'):
super(SpectrogramLinear, self).__init__(
width, height, bg_color, color_scheme)
[docs] @staticmethod
@interfacedoc
def id():
return "spectrogram_lin"
[docs] @staticmethod
@interfacedoc
def name():
return "Spectrogram Lin"
[docs] @staticmethod
@interfacedoc
def version():
return "1.0"
[docs] @interfacedoc
def setup(self, channels=None, samplerate=None, blocksize=None, totalframes=None):
super(SpectrogramLinear, self).setup(
channels, samplerate, blocksize, totalframes)
[docs] def set_scale(self):
"""generate the lookup which translates y-coordinate to fft-bin"""
f_min = float(self.lower_freq)
f_max = float(self.higher_freq)
y_min = f_min
y_max = f_max
for y in range(self.image_height):
freq = y_min + y / (self.image_height - 1.0) * (y_max - y_min)
fft_bin = freq / f_max * (self.fft_size / 2 + 1)
if fft_bin < self.fft_size / 2:
alpha = fft_bin - int(fft_bin)
self.y_to_bin.append((int(fft_bin), alpha * 255))