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diff --git a/src/MemlessPoly.cpp b/src/MemlessPoly.cpp
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+/*
+ Copyright (C) 2007, 2008, 2009, 2010, 2011 Her Majesty the Queen in
+ Right of Canada (Communications Research Center Canada)
+
+ Copyright (C) 2017
+ Matthias P. Braendli, matthias.braendli@mpb.li
+ Andreas Steger, andreas.steger@digris.ch
+
+ http://opendigitalradio.org
+
+ This block implements a memoryless polynom for digital predistortion.
+ For better performance, multiplying is done in another thread, leading
+ to a pipeline delay of two calls to MemlessPoly::process
+ */
+/*
+ This file is part of ODR-DabMod.
+
+ ODR-DabMod 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 of the
+ License, or (at your option) any later version.
+
+ ODR-DabMod 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 ODR-DabMod. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "MemlessPoly.h"
+#include "PcDebug.h"
+#include "Utils.h"
+
+#include <stdio.h>
+#include <stdexcept>
+
+#include <array>
+#include <iostream>
+#include <fstream>
+#include <memory>
+
+using namespace std;
+
+
+// By default the signal is unchanged
+static const std::array<float, 8> default_coefficients({
+ 1, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0
+ });
+
+
+MemlessPoly::MemlessPoly(const std::string& coefs_file) :
+ PipelinedModCodec(),
+ RemoteControllable("memlesspoly"),
+ m_coefs_file(coefs_file)
+{
+ PDEBUG("MemlessPoly::MemlessPoly(%s) @ %p\n",
+ coefs_file.c_str(), this);
+
+ RC_ADD_PARAMETER(ncoefs, "(Read-only) number of coefficients.");
+ RC_ADD_PARAMETER(coeffile, "Filename containing coefficients. When written to, the new file gets automatically loaded.");
+
+ load_coefficients(m_coefs_file);
+
+ start_pipeline_thread();
+}
+
+void MemlessPoly::load_coefficients(const std::string &coefFile)
+{
+ std::vector<float> coefs;
+ if (coefFile == "default") {
+ std::copy(default_coefficients.begin(), default_coefficients.end(),
+ std::back_inserter(coefs));
+ }
+ else {
+ std::ifstream coef_fstream(coefFile.c_str());
+ if(!coef_fstream) {
+ fprintf(stderr, "MemlessPoly: file %s could not be opened !\n", coefFile.c_str());
+ throw std::runtime_error("MemlessPoly: Could not open file with coefs! ");
+ }
+ int n_coefs;
+ coef_fstream >> n_coefs;
+
+ if (n_coefs <= 0) {
+ fprintf(stderr, "MemlessPoly: warning: coefs file has invalid format\n");
+ throw std::runtime_error("MemlessPoly: coefs file has invalid format.");
+ }
+
+ if (n_coefs != 8) {
+ throw std::runtime_error( "MemlessPoly: error: coefs file does not have 8 coefs\n");
+ }
+
+ fprintf(stderr, "MemlessPoly: Reading %d coefs...\n", n_coefs);
+
+ coefs.resize(n_coefs);
+
+ int n;
+ for (n = 0; n < n_coefs; n++) {
+ coef_fstream >> coefs[n];
+ PDEBUG("MemlessPoly: coef: %f\n", coefs[n] );
+ if (coef_fstream.eof()) {
+ fprintf(stderr, "MemlessPoly: file %s should contains %d coefs, but EOF reached "\
+ "after %d coefs !\n", coefFile.c_str(), n_coefs, n);
+ throw std::runtime_error("MemlessPoly: coefs file invalid ! ");
+ }
+ }
+ }
+
+ {
+ std::lock_guard<std::mutex> lock(m_coefs_mutex);
+
+ m_coefs = coefs;
+ }
+}
+
+
+int MemlessPoly::internal_process(Buffer* const dataIn, Buffer* dataOut)
+{
+ const float* in = reinterpret_cast<const float*>(dataIn->getData());
+ float* out = reinterpret_cast<float*>(dataOut->getData());
+ size_t sizeIn = dataIn->getLength() / sizeof(float);
+
+ {
+ std::lock_guard<std::mutex> lock(m_coefs_mutex);
+ for (size_t i = 0; i < sizeIn; i += 1) {
+ float mag = std::abs(in[i]);
+ //out[i] = in[i];
+ out[i] = in[i] * (
+ m_coefs[0] +
+ m_coefs[1] * mag +
+ m_coefs[2] * mag*mag +
+ m_coefs[3] * mag*mag*mag +
+ m_coefs[4] * mag*mag*mag*mag +
+ m_coefs[5] * mag*mag*mag*mag*mag +
+ m_coefs[6] * mag*mag*mag*mag*mag*mag +
+ m_coefs[7] * mag*mag*mag*mag*mag*mag*mag
+ );
+ }
+ }
+
+ return dataOut->getLength();
+}
+
+void MemlessPoly::set_parameter(const string& parameter, const string& value)
+{
+ stringstream ss(value);
+ ss.exceptions ( stringstream::failbit | stringstream::badbit );
+
+ if (parameter == "ncoefs") {
+ throw ParameterError("Parameter 'ncoefs' is read-only");
+ }
+ else if (parameter == "coeffile") {
+ try {
+ load_coefficients(value);
+ m_coefs_file = value;
+ }
+ catch (std::runtime_error &e) {
+ throw ParameterError(e.what());
+ }
+ }
+ else {
+ stringstream ss;
+ ss << "Parameter '" << parameter <<
+ "' is not exported by controllable " << get_rc_name();
+ throw ParameterError(ss.str());
+ }
+}
+
+const string MemlessPoly::get_parameter(const string& parameter) const
+{
+ stringstream ss;
+ if (parameter == "ncoefs") {
+ ss << m_coefs.size();
+ }
+ else if (parameter == "coefFile") {
+ ss << m_coefs_file;
+ }
+ else {
+ ss << "Parameter '" << parameter <<
+ "' is not exported by controllable " << get_rc_name();
+ throw ParameterError(ss.str());
+ }
+ return ss.str();
+}
+