Analog tv app (#334)

* Analog TV app (PAL)

* Icon on main menu

* Analog TV should be yellow

Works for PAL only know, it would be nice to add NTSC in the future, or some customizable sync

firmware/baseband/tv_collector.cpp

@@ -0,0 +1,122 @@
+/*
+ * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
+ * Copyright (C) 2020 Shao
+ *
+ * This file is part of PortaPack.
+ *
+ * This program 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 2, 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include "tv_collector.hpp"
+
+#include "dsp_fft.hpp"
+
+#include "utility.hpp"
+#include "event_m4.hpp"
+#include "portapack_shared_memory.hpp"
+
+#include "event_m4.hpp"
+
+#include <algorithm>
+
+void TvCollector::on_message(const Message* const message) {
+	switch(message->id) {
+	case Message::ID::UpdateSpectrum:
+		update();
+		break;
+
+	case Message::ID::SpectrumStreamingConfig:
+		set_state(*reinterpret_cast<const SpectrumStreamingConfigMessage*>(message));
+		break;
+
+	default:
+		break;
+	}
+}
+
+void TvCollector::set_state(const SpectrumStreamingConfigMessage& message) {
+	if( message.mode == SpectrumStreamingConfigMessage::Mode::Running ) {
+		start();
+	} else {
+		stop();
+	}
+}
+
+void TvCollector::start() {
+	streaming = true;
+	ChannelSpectrumConfigMessage message { &fifo };
+	shared_memory.application_queue.push(message);
+}
+
+void TvCollector::stop() {
+	streaming = false;
+	fifo.reset_in();
+}
+
+void TvCollector::set_decimation_factor(
+	const size_t decimation_factor
+) {
+	channel_spectrum_decimator.set_factor(decimation_factor);
+}
+
+/* TODO: Refactor to register task with idle thread?
+ * It's sad that the idle thread has to call all the way back here just to
+ * perform the deferred task on the buffer of data we prepared.
+ */
+
+void TvCollector::feed(
+	const buffer_c16_t& channel
+) {
+	// Called from baseband processing thread.
+	channel_spectrum_decimator.feed(channel,[this](const buffer_c16_t& data) {this->post_message(data);});
+}
+
+void TvCollector::post_message(const buffer_c16_t& data) {
+	// Called from baseband processing thread.
+        float re, im;
+	float mag;
+        float max;
+	if( streaming && !channel_spectrum_request_update ) {
+                for(size_t i=0; i<256; i++) 
+		{
+			const auto s = data.p[i];
+                        re = (float)(data.p[i].real());
+			im = (float)(data.p[i].imag());
+			mag = __builtin_sqrtf((re * re) + (im * im)) ;
+			channel_spectrum[i] = {mag, mag};
+		}
+                channel_spectrum_sampling_rate = data.sampling_rate;
+		channel_spectrum_request_update = true;
+		EventDispatcher::events_flag(EVT_MASK_SPECTRUM);
+	}
+}
+
+
+void TvCollector::update() {
+	// Called from idle thread (after EVT_MASK_SPECTRUM is flagged)
+	if( streaming && channel_spectrum_request_update ) {
+		ChannelSpectrum spectrum;
+		spectrum.sampling_rate = channel_spectrum_sampling_rate;
+		for(size_t i=0; i<spectrum.db.size(); i++) {
+                        const auto corrected_sample = channel_spectrum[i].real();
+			const unsigned int v = corrected_sample + 127.0f;
+			spectrum.db[i] = std::max(0U, std::min(255U, v));
+		}
+		fifo.in(spectrum);
+	}
+
+	channel_spectrum_request_update = false;
+}