Isolate filtered spectrum collection from WFM

firmware/baseband/CMakeLists.txt

@@ -124,6 +124,7 @@ set(CPPSRC
 	dsp_goertzel.cpp
 	matched_filter.cpp
 	spectrum_collector.cpp
+	filtered_spectrum_collector.cpp
 	tv_collector.cpp
 	stream_input.cpp
 	stream_output.cpp

firmware/baseband/filtered_spectrum_collector.cpp

@@ -0,0 +1,84 @@
+/*
+ * 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.
+ */
+
+#include "filtered_spectrum_collector.hpp"
+
+#include "dsp_fir_taps.hpp"
+#include "event_m4.hpp"
+
+#include <algorithm>
+
+void FilteredSpectrumCollector::on_message(const Message* const message) {
+    if (message->id == Message::ID::UpdateSpectrum) {
+        update();
+    }
+    SpectrumCollector::on_message(message);
+}
+
+void FilteredSpectrumCollector::start_capture(
+    const size_t decimation_factor) {
+    capture_decimation_ = decimation_factor;
+    capture_count_ = 0;
+    capture_ready_ = false;
+}
+
+bool FilteredSpectrumCollector::feed(
+    const buffer_c16_t& channel,
+    const int32_t filter_low_frequency,
+    const int32_t filter_high_frequency,
+    const int32_t filter_transition) {
+    set_filter(
+        filter_low_frequency,
+        filter_high_frequency,
+        filter_transition);
+
+    const size_t required_samples = 256 * capture_decimation_;
+    const size_t copy_count = std::min(
+        channel.count, required_samples - capture_count_);
+    std::copy_n(
+        channel.p,
+        copy_count,
+        capture_.begin() + capture_count_);
+    capture_count_ += copy_count;
+
+    if (capture_count_ == required_samples) {
+        sampling_rate_ = channel.sampling_rate / capture_decimation_;
+        capture_ready_ = true;
+        EventDispatcher::events_flag(EVT_MASK_SPECTRUM);
+        return true;
+    }
+    return false;
+}
+
+void FilteredSpectrumCollector::update() {
+    if (!capture_ready_) {
+        return;
+    }
+
+    decim_0_.configure(taps_audio_spectrum_halfband.taps);
+    const buffer_c16_t capture{
+        capture_.data(),
+        256 * capture_decimation_,
+        sampling_rate_ * capture_decimation_};
+    const buffer_c16_t stage_0{
+        stage_0_.data(),
+        stage_0_.size()};
+    const auto filtered = decim_0_.execute(capture, stage_0);
+
+    if (capture_decimation_ == 4) {
+        decim_1_.configure(taps_audio_spectrum_halfband.taps);
+        const buffer_c16_t stage_1{
+            stage_1_.data(),
+            stage_1_.size()};
+        post_message(decim_1_.execute(filtered, stage_1));
+    } else {
+        post_message(filtered);
+    }
+    capture_ready_ = false;
+}

firmware/baseband/filtered_spectrum_collector.hpp

@@ -0,0 +1,43 @@
+/*
+ * 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.
+ */
+
+#ifndef __FILTERED_SPECTRUM_COLLECTOR_H__
+#define __FILTERED_SPECTRUM_COLLECTOR_H__
+
+#include "dsp_decimate.hpp"
+#include "spectrum_collector.hpp"
+
+#include <array>
+
+class FilteredSpectrumCollector : public SpectrumCollector {
+   public:
+    void on_message(const Message* const message);
+
+    void start_capture(const size_t decimation_factor);
+    bool feed(
+        const buffer_c16_t& channel,
+        const int32_t filter_low_frequency,
+        const int32_t filter_high_frequency,
+        const int32_t filter_transition);
+
+   private:
+    std::array<complex16_t, 1024> capture_{};
+    std::array<complex16_t, 512> stage_0_{};
+    std::array<complex16_t, 256> stage_1_{};
+    dsp::decimate::FIRC16xR16x63HalfbandDecim2 decim_0_{};
+    dsp::decimate::FIRC16xR16x63HalfbandDecim2 decim_1_{};
+    size_t capture_count_{0};
+    size_t capture_decimation_{1};
+    uint32_t sampling_rate_{0};
+    bool capture_ready_{false};
+
+    void update();
+};
+
+#endif /*__FILTERED_SPECTRUM_COLLECTOR_H__*/

firmware/baseband/proc_am_audio.cpp

@@ -51,12 +51,12 @@ void NarrowbandAMAudio::execute(const buffer_c8_t& buffer) {
     if (!spectrum_capture_active &&
         spectrum_samples >= spectrum_interval_samples) {
         spectrum_samples -= spectrum_interval_samples;
-        channel_spectrum.start_filtered_capture(spectrum_zoom_x2 ? 4 : 2);
+        channel_spectrum.start_capture(spectrum_zoom_x2 ? 4 : 2);
         spectrum_capture_active = true;
     }
 
     if (spectrum_capture_active &&
-        channel_spectrum.feed_filtered(
+        channel_spectrum.feed(
             audio_decim_0_out,
             channel_filter_low_f,
             channel_filter_high_f,

firmware/baseband/proc_am_audio.hpp

@@ -32,7 +32,7 @@
 #include "audio_compressor.hpp"
 
 #include "audio_output.hpp"
-#include "spectrum_collector.hpp"
+#include "filtered_spectrum_collector.hpp"
 
 #include <cstdint>
 
@@ -80,7 +80,7 @@ class NarrowbandAMAudio : public BasebandProcessor {
     FeedForwardCompressor audio_compressor{};
     AudioOutput audio_output{};
 
-    SpectrumCollector channel_spectrum{};
+    FilteredSpectrumCollector channel_spectrum{};
 
     /* NB: Threads should be the last members in the class definition. */
 #ifdef PRALINE

firmware/baseband/proc_nfm_audio.cpp

@@ -57,12 +57,12 @@ void NarrowbandFMAudio::execute(const buffer_c8_t& buffer) {
     if (!spectrum_capture_active &&
         spectrum_samples >= spectrum_interval_samples) {
         spectrum_samples -= spectrum_interval_samples;
-        channel_spectrum.start_filtered_capture(2);
+        channel_spectrum.start_capture(2);
         spectrum_capture_active = true;
     }
 
     if (spectrum_capture_active &&
-        channel_spectrum.feed_filtered(
+        channel_spectrum.feed(
             audio_decim_0_out,
             channel_filter_low_f,
             channel_filter_high_f,

firmware/baseband/proc_nfm_audio.hpp

@@ -33,7 +33,7 @@
 #include "dsp_iir.hpp"
 
 #include "audio_output.hpp"
-#include "spectrum_collector.hpp"
+#include "filtered_spectrum_collector.hpp"
 
 #include <cstdint>
 
@@ -87,7 +87,7 @@ class NarrowbandFMAudio : public BasebandProcessor {
 
     AudioOutput audio_output{};
 
-    SpectrumCollector channel_spectrum{};
+    FilteredSpectrumCollector channel_spectrum{};
     size_t spectrum_interval_samples{0};
     size_t spectrum_samples{0};
     bool spectrum_capture_active{false};

firmware/baseband/spectrum_collector.cpp

@@ -22,7 +22,6 @@
 #include "spectrum_collector.hpp"
 
 #include "dsp_fft.hpp"
-#include "dsp_fir_taps.hpp"
 
 #include "utility.hpp"
 #include "event_m4.hpp"
@@ -80,9 +79,10 @@ bool SpectrumCollector::feed(
     const int32_t filter_high_frequency,
     const int32_t filter_transition) {
     // Called from baseband processing thread.
-    channel_filter_low_frequency = filter_low_frequency;
-    channel_filter_high_frequency = filter_high_frequency;
-    channel_filter_transition = filter_transition;
+    set_filter(
+        filter_low_frequency,
+        filter_high_frequency,
+        filter_transition);
 
     bool block_completed = false;
     channel_spectrum_decimator.feed(
@@ -94,40 +94,13 @@ bool SpectrumCollector::feed(
     return block_completed;
 }
 
-void SpectrumCollector::start_filtered_capture(
-    const size_t decimation_factor) {
-    filtered_capture_decimation_ = decimation_factor;
-    filtered_capture_count_ = 0;
-    filtered_capture_ready_ = false;
-}
-
-bool SpectrumCollector::feed_filtered(
-    const buffer_c16_t& channel,
+void SpectrumCollector::set_filter(
     const int32_t filter_low_frequency,
     const int32_t filter_high_frequency,
     const int32_t filter_transition) {
     channel_filter_low_frequency = filter_low_frequency;
     channel_filter_high_frequency = filter_high_frequency;
     channel_filter_transition = filter_transition;
-
-    const size_t required_samples = 256 * filtered_capture_decimation_;
-    const size_t copy_count = std::min(
-        channel.count, required_samples - filtered_capture_count_);
-    std::copy_n(
-        channel.p,
-        copy_count,
-        filtered_capture_.begin() + filtered_capture_count_);
-    filtered_capture_count_ += copy_count;
-
-    if (filtered_capture_count_ == required_samples) {
-        channel_spectrum_sampling_rate =
-            channel.sampling_rate / filtered_capture_decimation_;
-        filtered_capture_ready_ = true;
-        channel_spectrum_request_update = true;
-        EventDispatcher::events_flag(EVT_MASK_SPECTRUM);
-        return true;
-    }
-    return false;
 }
 
 void SpectrumCollector::post_message(const buffer_c16_t& data) {
@@ -171,31 +144,6 @@ static typename T::value_type spectrum_window_blackman_3(const T& s, const size_
 void SpectrumCollector::update() {
     // Called from idle thread (after EVT_MASK_SPECTRUM is flagged)
     if (streaming && channel_spectrum_request_update) {
-        if (filtered_capture_ready_) {
-            filtered_decim_0_.configure(taps_audio_spectrum_halfband.taps);
-            const buffer_c16_t capture{
-                filtered_capture_.data(),
-                256 * filtered_capture_decimation_,
-                channel_spectrum_sampling_rate * filtered_capture_decimation_};
-            const buffer_c16_t stage_0{
-                filtered_stage_0_.data(),
-                filtered_stage_0_.size()};
-            const auto filtered = filtered_decim_0_.execute(capture, stage_0);
-
-            if (filtered_capture_decimation_ == 4) {
-                filtered_decim_1_.configure(taps_audio_spectrum_halfband.taps);
-                const buffer_c16_t stage_1{
-                    filtered_stage_1_.data(),
-                    filtered_stage_1_.size()};
-                const auto zoom_filtered =
-                    filtered_decim_1_.execute(filtered, stage_1);
-                fft_swap(zoom_filtered, channel_spectrum);
-            } else {
-                fft_swap(filtered, channel_spectrum);
-            }
-            filtered_capture_ready_ = false;
-        }
-
         /* Decimated buffer is full. Compute spectrum. */
         fft_c_preswapped(channel_spectrum, 0, 8);
 

firmware/baseband/spectrum_collector.hpp

@@ -29,7 +29,6 @@
 #include "complex.hpp"
 
 #include "block_decimator.hpp"
-#include "dsp_decimate.hpp"
 
 #include <cstdint>
 #include <array>
@@ -51,12 +50,12 @@ class SpectrumCollector {
         const int32_t filter_high_frequency,
         const int32_t filter_transition);
 
-    void start_filtered_capture(const size_t decimation_factor);
-    bool feed_filtered(
-        const buffer_c16_t& channel,
+   protected:
+    void set_filter(
         const int32_t filter_low_frequency,
         const int32_t filter_high_frequency,
         const int32_t filter_transition);
+    void post_message(const buffer_c16_t& data);
 
    private:
     BlockDecimator<complex16_t, 256> channel_spectrum_decimator{1};
@@ -66,22 +65,12 @@ class SpectrumCollector {
     volatile bool channel_spectrum_request_update{false};
     bool streaming{false};
     std::array<std::complex<float>, 256> channel_spectrum{};
-    std::array<complex16_t, 1024> filtered_capture_{};
-    std::array<complex16_t, 512> filtered_stage_0_{};
-    std::array<complex16_t, 256> filtered_stage_1_{};
-    dsp::decimate::FIRC16xR16x63HalfbandDecim2 filtered_decim_0_{};
-    dsp::decimate::FIRC16xR16x63HalfbandDecim2 filtered_decim_1_{};
-    size_t filtered_capture_count_{0};
-    size_t filtered_capture_decimation_{1};
-    bool filtered_capture_ready_{false};
     uint32_t channel_spectrum_sampling_rate{0};
     int32_t channel_filter_low_frequency{0};
     int32_t channel_filter_high_frequency{0};
     int32_t channel_filter_transition{0};
     int32_t channel_filter_offset{0};
 
-    void post_message(const buffer_c16_t& data);
-
     void set_state(const SpectrumStreamingConfigMessage& message);
     void start();
     void stop();