path: root/gr-wxgui/src/python/fft_window.py

#
# Copyright 2008 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# GNU Radio 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, or (at your option)
# any later version.
#
# GNU Radio 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.
#
# You should have received a copy of the GNU General Public License
# along with GNU Radio; see the file COPYING.  If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
#

##################################################
# Imports
##################################################
import plotter
import common
import wx
import numpy
import math
import pubsub
from constants import *
from gnuradio import gr #for gr.prefs
import forms

##################################################
# Constants
##################################################
SLIDER_STEPS = 100
AVG_ALPHA_MIN_EXP, AVG_ALPHA_MAX_EXP = -3, 0
DEFAULT_WIN_SIZE = (600, 300)
DEFAULT_FRAME_RATE = gr.prefs().get_long('wxgui', 'fft_rate', 30)
DB_DIV_MIN, DB_DIV_MAX = 1, 20
FFT_PLOT_COLOR_SPEC = (0.3, 0.3, 1.0)
PEAK_VALS_COLOR_SPEC = (0.0, 0.8, 0.0)
EMPTY_TRACE = list()
TRACES = ('A', 'B')
TRACES_COLOR_SPEC = {
	'A': (1.0, 0.0, 0.0),
	'B': (0.8, 0.0, 0.8),
}

##################################################
# FFT window control panel
##################################################
class control_panel(wx.Panel):
	"""
	A control panel with wx widgits to control the plotter and fft block chain.
	"""

	def __init__(self, parent):
		"""
		Create a new control panel.
		@param parent the wx parent window
		"""
		self.parent = parent
		wx.Panel.__init__(self, parent, style=wx.SUNKEN_BORDER)
		control_box = wx.BoxSizer(wx.VERTICAL)
		control_box.AddStretchSpacer()
		#checkboxes for average and peak hold
		options_box = forms.static_box_sizer(
			parent=self, sizer=control_box, label='Trace Options',
			bold=True, orient=wx.VERTICAL,
		)
		forms.check_box(
			sizer=options_box, parent=self, label='Peak Hold',
			ps=parent, key=PEAK_HOLD_KEY,
		)
		forms.check_box(
			sizer=options_box, parent=self, label='Average',
			ps=parent, key=AVERAGE_KEY,
		)
		#static text and slider for averaging
		avg_alpha_text = forms.static_text(
			sizer=options_box, parent=self, label='Avg Alpha',
			converter=forms.float_converter(lambda x: '%.4f'%x),
			ps=parent, key=AVG_ALPHA_KEY, width=50,
		)
		avg_alpha_slider = forms.log_slider(
			sizer=options_box, parent=self,
			min_exp=AVG_ALPHA_MIN_EXP,
			max_exp=AVG_ALPHA_MAX_EXP,
			num_steps=SLIDER_STEPS,
			ps=parent, key=AVG_ALPHA_KEY,
		)
		for widget in (avg_alpha_text, avg_alpha_slider):
			parent.subscribe(AVERAGE_KEY, widget.Enable)
			widget.Enable(parent[AVERAGE_KEY])
		
		#trace menu
		for trace in TRACES:
			trace_box = wx.BoxSizer(wx.HORIZONTAL)
			options_box.Add(trace_box, 0, wx.EXPAND)
			forms.check_box(
				sizer=trace_box, parent=self,
				ps=parent, key=TRACE_SHOW_KEY+trace,
				label='Trace %s'%trace,
			)
			trace_box.AddSpacer(10)
			forms.single_button(
				sizer=trace_box, parent=self,
				ps=parent, key=TRACE_STORE_KEY+trace,
				label='Store', style=wx.BU_EXACTFIT,
			)
			trace_box.AddSpacer(10)
		#radio buttons for div size
		control_box.AddStretchSpacer()
		y_ctrl_box = forms.static_box_sizer(
			parent=self, sizer=control_box, label='Axis Options',
			bold=True, orient=wx.VERTICAL,
		)
		forms.incr_decr_buttons(
			parent=self, sizer=y_ctrl_box, label='dB/Div',
			on_incr=self._on_incr_db_div, on_decr=self._on_decr_db_div,
		)
		#ref lvl buttons
		forms.incr_decr_buttons(
			parent=self, sizer=y_ctrl_box, label='Ref Level',
			on_incr=self._on_incr_ref_level, on_decr=self._on_decr_ref_level,
		)
		y_ctrl_box.AddSpacer(2)
		#autoscale
		forms.single_button(
			sizer=y_ctrl_box, parent=self, label='Autoscale',
			callback=self.parent.autoscale,
		)
		#run/stop
		control_box.AddStretchSpacer()
		forms.toggle_button(
			sizer=control_box, parent=self,
			true_label='Stop', false_label='Run',
			ps=parent, key=RUNNING_KEY,
		)
		#set sizer
		self.SetSizerAndFit(control_box)
		#mouse wheel event
		def on_mouse_wheel(event):
			if event.GetWheelRotation() < 0: self._on_incr_ref_level(event)
			else: self._on_decr_ref_level(event)
		parent.plotter.Bind(wx.EVT_MOUSEWHEEL, on_mouse_wheel)

	##################################################
	# Event handlers
	##################################################
	def _on_incr_ref_level(self, event):
		self.parent[REF_LEVEL_KEY] = self.parent[REF_LEVEL_KEY] + self.parent[Y_PER_DIV_KEY]
	def _on_decr_ref_level(self, event):
		self.parent[REF_LEVEL_KEY] = self.parent[REF_LEVEL_KEY] - self.parent[Y_PER_DIV_KEY]
	def _on_incr_db_div(self, event):
		self.parent[Y_PER_DIV_KEY] = min(DB_DIV_MAX, self.parent[Y_PER_DIV_KEY]*2)
	def _on_decr_db_div(self, event):
		self.parent[Y_PER_DIV_KEY] = max(DB_DIV_MIN, self.parent[Y_PER_DIV_KEY]/2)

##################################################
# FFT window with plotter and control panel
##################################################
class fft_window(wx.Panel, pubsub.pubsub):
	def __init__(
		self,
		parent,
		controller,
		size,
		title,
		real,
		fft_size,
		baseband_freq,
		sample_rate_key,
		y_per_div,
		y_divs,
		ref_level,
		average_key,
		avg_alpha_key,
		peak_hold,
		msg_key,
	):
		pubsub.pubsub.__init__(self)
		#setup
		self.samples = EMPTY_TRACE
		self.real = real
		self.fft_size = fft_size
		self._reset_peak_vals()
		self._traces = dict()
		#proxy the keys
		self.proxy(MSG_KEY, controller, msg_key)
		self.proxy(AVERAGE_KEY, controller, average_key)
		self.proxy(AVG_ALPHA_KEY, controller, avg_alpha_key)
		self.proxy(SAMPLE_RATE_KEY, controller, sample_rate_key)
		#initialize values
		self[PEAK_HOLD_KEY] = peak_hold
		self[Y_PER_DIV_KEY] = y_per_div
		self[Y_DIVS_KEY] = y_divs
		self[X_DIVS_KEY] = 8 #approximate
		self[REF_LEVEL_KEY] = ref_level
		self[BASEBAND_FREQ_KEY] = baseband_freq
		self[RUNNING_KEY] = True
		for trace in TRACES:
			#a function that returns a function
			#so the function wont use local trace
			def new_store_trace(my_trace):
				def store_trace(*args):
					self._traces[my_trace] = self.samples
					self.update_grid()
				return store_trace
			def new_toggle_trace(my_trace):
				def toggle_trace(toggle):
					#do an automatic store if toggled on and empty trace
					if toggle and not len(self._traces[my_trace]):
						self._traces[my_trace] = self.samples
					self.update_grid()
				return toggle_trace
			self._traces[trace] = EMPTY_TRACE
			self[TRACE_STORE_KEY+trace] = False
			self[TRACE_SHOW_KEY+trace] = False
			self.subscribe(TRACE_STORE_KEY+trace, new_store_trace(trace))
			self.subscribe(TRACE_SHOW_KEY+trace, new_toggle_trace(trace))
		#init panel and plot
		wx.Panel.__init__(self, parent, style=wx.SIMPLE_BORDER)
		self.plotter = plotter.channel_plotter(self)
		self.plotter.SetSize(wx.Size(*size))
		self.plotter.set_title(title)
		self.plotter.enable_legend(True)
		self.plotter.enable_point_label(True)
		self.plotter.enable_grid_lines(True)
		#setup the box with plot and controls
		self.control_panel = control_panel(self)
		main_box = wx.BoxSizer(wx.HORIZONTAL)
		main_box.Add(self.plotter, 1, wx.EXPAND)
		main_box.Add(self.control_panel, 0, wx.EXPAND)
		self.SetSizerAndFit(main_box)
		#register events
		self.subscribe(AVERAGE_KEY, self._reset_peak_vals)
		self.subscribe(MSG_KEY, self.handle_msg)
		self.subscribe(SAMPLE_RATE_KEY, self.update_grid)
		for key in (
			BASEBAND_FREQ_KEY,
			Y_PER_DIV_KEY, X_DIVS_KEY,
			Y_DIVS_KEY, REF_LEVEL_KEY,
		): self.subscribe(key, self.update_grid)
		#initial update
		self.update_grid()

	def autoscale(self, *args):
		"""
		Autoscale the fft plot to the last frame.
		Set the dynamic range and reference level.
		"""
		if not len(self.samples): return
		#get the peak level (max of the samples)
		peak_level = numpy.max(self.samples)
		#separate noise samples
		noise_samps = numpy.sort(self.samples)[:len(self.samples)/2]
		#get the noise floor
		noise_floor = numpy.average(noise_samps)
		#get the noise deviation
		noise_dev = numpy.std(noise_samps)
		#determine the maximum and minimum levels
		max_level = peak_level
		min_level = noise_floor - abs(2*noise_dev)
		#set the range to a clean number of the dynamic range
		self[Y_PER_DIV_KEY] = common.get_clean_num(1+(max_level - min_level)/self[Y_DIVS_KEY])
		#set the reference level to a multiple of y per div
		self[REF_LEVEL_KEY] = self[Y_PER_DIV_KEY]*round(.5+max_level/self[Y_PER_DIV_KEY])

	def _reset_peak_vals(self, *args): self.peak_vals = EMPTY_TRACE

	def handle_msg(self, msg):
		"""
		Handle the message from the fft sink message queue.
		If complex, reorder the fft samples so the negative bins come first.
		If real, keep take only the positive bins.
		Plot the samples onto the grid as channel 1.
		If peak hold is enabled, plot peak vals as channel 2.
		@param msg the fft array as a character array
		"""
		if not self[RUNNING_KEY]: return
		#convert to floating point numbers
		samples = numpy.fromstring(msg, numpy.float32)[:self.fft_size] #only take first frame
		num_samps = len(samples)
		#reorder fft
		if self.real: samples = samples[:(num_samps+1)/2]
		else: samples = numpy.concatenate((samples[num_samps/2+1:], samples[:(num_samps+1)/2]))
		self.samples = samples
		#peak hold calculation
		if self[PEAK_HOLD_KEY]:
			if len(self.peak_vals) != len(samples): self.peak_vals = samples
			self.peak_vals = numpy.maximum(samples, self.peak_vals)
			#plot the peak hold
			self.plotter.set_waveform(
				channel='Peak',
				samples=self.peak_vals,
				color_spec=PEAK_VALS_COLOR_SPEC,
			)
		else:
			self._reset_peak_vals()
			self.plotter.clear_waveform(channel='Peak')
		#plot the fft
		self.plotter.set_waveform(
			channel='FFT',
			samples=samples,
			color_spec=FFT_PLOT_COLOR_SPEC,
		)
		#update the plotter
		self.plotter.update()

	def update_grid(self, *args):
		"""
		Update the plotter grid.
		This update method is dependent on the variables below.
		Determine the x and y axis grid parameters.
		The x axis depends on sample rate, baseband freq, and x divs.
		The y axis depends on y per div, y divs, and ref level.
		"""
		for trace in TRACES:
			channel = '%s'%trace.upper()
			if self[TRACE_SHOW_KEY+trace]:
				self.plotter.set_waveform(
					channel=channel,
					samples=self._traces[trace],
					color_spec=TRACES_COLOR_SPEC[trace],
				)
			else: self.plotter.clear_waveform(channel=channel)
		#grid parameters
		sample_rate = self[SAMPLE_RATE_KEY]
		baseband_freq = self[BASEBAND_FREQ_KEY]
		y_per_div = self[Y_PER_DIV_KEY]
		y_divs = self[Y_DIVS_KEY]
		x_divs = self[X_DIVS_KEY]
		ref_level = self[REF_LEVEL_KEY]
		#determine best fitting x_per_div
		if self.real: x_width = sample_rate/2.0
		else: x_width = sample_rate/1.0
		x_per_div = common.get_clean_num(x_width/x_divs)
		#update the x grid
		if self.real:
			self.plotter.set_x_grid(
				baseband_freq,
				baseband_freq + sample_rate/2.0,
				x_per_div, True,
			)
		else:
			self.plotter.set_x_grid(
				baseband_freq - sample_rate/2.0,
				baseband_freq + sample_rate/2.0,
				x_per_div, True,
			)
		#update x units
		self.plotter.set_x_label('Frequency', 'Hz')
		#update y grid
		self.plotter.set_y_grid(ref_level-y_per_div*y_divs, ref_level, y_per_div)
		#update y units
		self.plotter.set_y_label('Amplitude', 'dB')
		#update plotter
		self.plotter.update()