WeFax rx ext app (#2566)

* wf3

* Ookbrute (#2354)

* Revert "Ookbrute (#2354)"

This reverts commit abb8143eec.

* fix

* test edition

* re enable ble

* re enable ert

* steal amfm stuff

* something happens

* save bmp on start btn

* kinda works

* exit crash fixed

* redline, remove some hardcoded

* removed cpu killer red line, and some fixes

* simplify #1

* seems ok. time to improve

* added hidden freq offset to receiver model, so wefax can be set to the "correct" freq without users needs to substract 300 hz

* badly implemented sync detection, and disabled it.

* fix for fix

* fixes

* fix offset to real life off

* no line on freq enter

* fixes

firmware/baseband/CMakeLists.txt

@@ -668,6 +668,14 @@ DeclareTargets(POSK ookstream)
 
 
 
+### WeFax Rx
+
+set(MODE_CPPSRC
+	proc_wefaxrx.cpp
+)
+DeclareTargets(PWFX wefaxrx)
+
+
 ### HackRF "factory" firmware
 
 add_custom_command(

firmware/baseband/proc_wefaxrx.cpp

@@ -0,0 +1,186 @@
+/*
+ * Copyright (C) 2025 Brumi, HTotoo
+ *
+ * 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 "proc_wefaxrx.hpp"
+#include "sine_table_int8.hpp"
+#include "portapack_shared_memory.hpp"
+
+#include "audio_dma.hpp"
+#include "math.h"
+#include "event_m4.hpp"
+#include "fxpt_atan2.hpp"
+
+#include <cstdint>
+#include <cstddef>
+
+#define STARTSIGNAL_TH 0.33
+#define STARTSIGNAL_NEEDCNT 110
+#define STARTSIGNAL_MAXBAD 20
+
+#define WEFAX_PX_SIZE 840.0
+
+// updates the per pixel timers
+void WeFaxRx::update_params() {
+    switch (ioc_mode) {
+        case 1:
+            freq_start_tone = 675;
+            break;
+        default:
+        case 0:
+            freq_start_tone = 300;
+            break;
+    }
+    // 840 px / line with line start
+    pxRem = (double)channel_filter_input_fs / ((lpm / 60.0) * WEFAX_PX_SIZE);
+    samples_per_pixel = pxRem;
+    pxRem -= samples_per_pixel;
+    pxRoll = 0;
+    status_message.state = 0;
+    shared_memory.application_queue.push(status_message);
+}
+
+void WeFaxRx::execute(const buffer_c8_t& buffer) {
+    // This is called at 3072000 / 2048 = 1500Hz
+    if (!configured) return;
+    const auto decim_0_out = decim_0.execute(buffer, dst_buffer);
+    const auto decim_1_out = decim_1.execute(decim_0_out, dst_buffer);
+
+    channel_spectrum.feed(decim_1_out, channel_filter_low_f, channel_filter_high_f, channel_filter_transition);
+
+    const auto decim_2_out = decim_2.execute(decim_1_out, dst_buffer);
+    const auto channel_out = channel_filter.execute(decim_2_out, dst_buffer);
+
+    feed_channel_stats(channel_out);
+    auto audio = demod_ssb_fm.execute(channel_out, audio_buffer);
+    audio_compressor.execute_in_place(audio);
+    audio_output.write(audio);
+
+    for (size_t c = 0; c < audio.count; c++) {
+        if (status_message.state == 0 && false) {  // disabled this due to so sensitive to noise
+            // first look for the sync!
+            if (audio.p[c] <= STARTSIGNAL_TH && audio.p[c] >= 0.0001) {
+                sync_cnt++;
+                if (sync_cnt >= STARTSIGNAL_NEEDCNT) {
+                    status_message.state = 1;
+                    shared_memory.application_queue.push(status_message);
+                    sync_cnt = 0;
+                    syncnot_cnt = 0;
+                }
+            } else {
+                syncnot_cnt++;
+                if (syncnot_cnt >= STARTSIGNAL_MAXBAD) {
+                    sync_cnt = 0;
+                    syncnot_cnt = 0;
+                }
+            }
+        } else {
+            cnt++;
+            if (cnt >= (samples_per_pixel + (uint32_t)pxRoll)) {  // got a pixel
+                cnt = 0;
+                if (pxRoll >= 1) pxRoll -= 1.0;
+                pxRoll += pxRem;
+
+                if (image_message.cnt < 400) {
+                    if (audio.p[c] >= 0.68) {
+                        image_message.image[image_message.cnt++] = 255;
+                    } else if (audio.p[c] >= 0.45) {
+                        image_message.image[image_message.cnt++] = (uint8_t)(((audio.p[c] - 0.45f) * 1108));
+                    } else {
+                        image_message.image[image_message.cnt++] = 0;
+                    }
+                }
+                if (image_message.cnt >= 399) {
+                    shared_memory.application_queue.push(image_message);
+                    image_message.cnt = 0;
+                    if (status_message.state != 2) {
+                        status_message.state = 2;
+                        shared_memory.application_queue.push(status_message);
+                    }
+                }
+            }
+        }
+    }
+}
+
+void WeFaxRx::on_message(const Message* const message) {
+    switch (message->id) {
+        case Message::ID::UpdateSpectrum:
+        case Message::ID::SpectrumStreamingConfig:
+            channel_spectrum.on_message(message);
+            break;
+
+        case Message::ID::WeFaxRxConfigure:
+            configure(*reinterpret_cast<const WeFaxRxConfigureMessage*>(message));
+            break;
+
+        case Message::ID::CaptureConfig:
+            capture_config(*reinterpret_cast<const CaptureConfigMessage*>(message));
+            break;
+
+        default:
+            break;
+    }
+}
+
+void WeFaxRx::configure(const WeFaxRxConfigureMessage& message) {
+    constexpr size_t decim_0_input_fs = baseband_fs;
+    constexpr size_t decim_0_output_fs = decim_0_input_fs / decim_0.decimation_factor;
+
+    constexpr size_t decim_1_input_fs = decim_0_output_fs;
+    constexpr size_t decim_1_output_fs = decim_1_input_fs / decim_1.decimation_factor;
+
+    constexpr size_t decim_2_input_fs = decim_1_output_fs;
+    constexpr size_t decim_2_output_fs = decim_2_input_fs / decim_2_decimation_factor;
+
+    channel_filter_input_fs = decim_2_output_fs;
+    // const size_t channel_filter_output_fs = channel_filter_input_fs / channel_filter_decimation_factor;
+
+    decim_0.configure(taps_6k0_decim_0.taps);
+    decim_1.configure(taps_6k0_decim_1.taps);
+    decim_2.configure(taps_6k0_decim_2.taps, decim_2_decimation_factor);
+    channel_filter.configure(taps_2k6_usb_wefax_channel.taps, channel_filter_decimation_factor);
+    channel_filter_low_f = taps_2k6_usb_wefax_channel.low_frequency_normalized * channel_filter_input_fs;
+    channel_filter_high_f = taps_2k6_usb_wefax_channel.high_frequency_normalized * channel_filter_input_fs;
+    channel_filter_transition = taps_2k6_usb_wefax_channel.transition_normalized * channel_filter_input_fs;
+    channel_spectrum.set_decimation_factor(1.0f);
+    audio_output.configure(audio_12k_lpf_1500hz_config);  // hpf in all AM demod modes (AM-6K/9K, USB/LSB,DSB), except Wefax (lpf there).
+
+    lpm = message.lpm;
+    ioc_mode = message.ioc;
+
+    update_params();
+    configured = true;
+}
+
+void WeFaxRx::capture_config(const CaptureConfigMessage& message) {
+    if (message.config) {
+        audio_output.set_stream(std::make_unique<StreamInput>(message.config));
+    } else {
+        audio_output.set_stream(nullptr);
+    }
+}
+
+int main() {
+    audio::dma::init_audio_out();
+    EventDispatcher event_dispatcher{std::make_unique<WeFaxRx>()};
+    event_dispatcher.run();
+    return 0;
+}

firmware/baseband/proc_wefaxrx.hpp

@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2025 Brumi, HTotoo
+ *
+ * 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.
+ */
+
+#ifndef __PROC_WEFAXRX_H__
+#define __PROC_WEFAXRX_H__
+
+#include "baseband_processor.hpp"
+#include "baseband_thread.hpp"
+#include "rssi_thread.hpp"
+
+#include "dsp_decimate.hpp"
+#include "dsp_demodulate.hpp"
+#include "dsp_iir.hpp"
+#include "audio_compressor.hpp"
+
+#include "audio_output.hpp"
+#include "spectrum_collector.hpp"
+
+#include <cstdint>
+
+class WeFaxRx : public BasebandProcessor {
+   public:
+    void execute(const buffer_c8_t& buffer) override;
+    void on_message(const Message* const message) override;
+
+   private:
+    void update_params();
+    // todo rethink
+    uint8_t lpm = 120;     // 60, 90, 100, 120, 180, 240 lpm
+    uint8_t ioc_mode = 0;  // 0 - ioc576, 1 - ioc 288, 2 - colour fax
+
+    uint32_t samples_per_pixel = 0;
+    // not yet used:
+    uint32_t time_start_tone = 3000;  // 3s - 5s
+    uint32_t freq_start_tone = 300;   // 300hz for ioc576 675hz for ioc288, 200hz for colour fax
+    uint32_t freq_stop_tone = 450;    // 450hz for the 3-5s stop tone
+
+    // to exactly match the pixel / samples.
+    double pxRem = 0;   // if has remainder, it'll store it
+    double pxRoll = 0;  // summs remainders, so won't misalign
+
+    uint32_t cnt = 0;  // signal counter
+    uint16_t sync_cnt = 0;
+    uint16_t syncnot_cnt = 0;
+
+    static constexpr size_t baseband_fs = 3072000;
+    static constexpr size_t decim_2_decimation_factor = 4;
+    static constexpr size_t channel_filter_decimation_factor = 1;
+
+    std::array<complex16_t, 512> dst{};
+    const buffer_c16_t dst_buffer{
+        dst.data(),
+        dst.size()};
+    std::array<float, 32> audio{};
+    const buffer_f32_t audio_buffer{
+        audio.data(),
+        audio.size()};
+    size_t channel_filter_input_fs = 0;
+
+    dsp::decimate::FIRC8xR16x24FS4Decim8 decim_0{};
+    dsp::decimate::FIRC16xR16x32Decim8 decim_1{};
+    dsp::decimate::FIRAndDecimateComplex decim_2{};
+    dsp::decimate::FIRAndDecimateComplex channel_filter{};
+    int32_t channel_filter_low_f = 0;
+    int32_t channel_filter_high_f = 0;
+    int32_t channel_filter_transition = 0;
+    bool configured{false};
+
+    dsp::demodulate::SSB_FM demod_ssb_fm{};  // added for Wfax mode.
+    FeedForwardCompressor audio_compressor{};
+    AudioOutput audio_output{};
+
+    SpectrumCollector channel_spectrum{};
+
+    void configure(const WeFaxRxConfigureMessage& message);
+    void capture_config(const CaptureConfigMessage& message);
+
+    WeFaxRxStatusDataMessage status_message{0};
+    WeFaxRxImageDataMessage image_message{};
+
+    /* NB: Threads should be the last members in the class definition. */
+    BasebandThread baseband_thread{baseband_fs, this, baseband::Direction::Receive};
+    RSSIThread rssi_thread{};
+};
+
+#endif /*__PROC_WEFAXRX_H__*/