aboutsummaryrefslogtreecommitdiffstats
path: root/src/MemlessPoly.cpp
blob: d665839fc7ddc4aeaa82fc16df1cb90f2a70eb80 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
/*
   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/>.
 */

#pragma GCC optimize ("O3")

#include "MemlessPoly.h"
#include "PcDebug.h"
#include "Utils.h"

#include <stdio.h>
#include <stdexcept>

#include <future>
#include <array>
#include <iostream>
#include <fstream>
#include <memory>
#include <complex>

using namespace std;

#define NUM_COEFS_AM 5
#define NUM_COEFS_PM 5

MemlessPoly::MemlessPoly(const std::string& coefs_am_file, const std::string& coefs_pm_file, unsigned int num_threads) :
    PipelinedModCodec(),
    RemoteControllable("memlesspoly"),
    m_num_threads(num_threads),
    m_coefs_am(),
    m_coefs_am_file(coefs_am_file),
    m_coefs_am_mutex(),
    m_coefs_pm(),
    m_coefs_pm_file(coefs_pm_file),
    m_coefs_pm_mutex()
{
    PDEBUG("MemlessPoly::MemlessPoly(%s) @ %p\n",
            coefs_am_file.c_str(), this);
    PDEBUG("MemlessPoly::MemlessPoly(%s) @ %p\n",
            coefs_pm_file.c_str(), this);

    if (m_num_threads == 0) {
        const unsigned int hw_concurrency = std::thread::hardware_concurrency();
        etiLog.level(info) << "Polynomial Predistorter will use " <<
            hw_concurrency << " threads (auto detected)";
    }
    else {
        etiLog.level(info) << "Polynomial Predistorter will use " <<
            m_num_threads << " threads (set in config file)";
    }

    RC_ADD_PARAMETER(ncoefs_am, "(Read-only) number of coefficients for amplitude.");
    RC_ADD_PARAMETER(coeffile_am, "Filename containing coefficients for amplitude. When written to, the new file gets automatically loaded.");

    RC_ADD_PARAMETER(ncoefs_pm, "(Read-only) number of coefficients for phase.");
    RC_ADD_PARAMETER(coeffile_pm, "Filename containing coefficients for amplitude. When written to, the new file gets automatically loaded.");

    load_coefficients_am(m_coefs_am_file);
    load_coefficients_pm(m_coefs_pm_file);

    start_pipeline_thread();
}

void MemlessPoly::load_coefficients_am(const std::string &coefFile_am)
{
    std::vector<float> coefs_am;
    std::ifstream coef_fstream_am(coefFile_am.c_str());
    if (!coef_fstream_am) {
        throw std::runtime_error("MemlessPoly: Could not open file with coefs_am!");
    }
    int n_coefs_am;
    coef_fstream_am >> n_coefs_am;

    if (n_coefs_am <= 0) {
        throw std::runtime_error("MemlessPoly: coefs_am file has invalid format.");
    }
    else if (n_coefs_am != NUM_COEFS_AM) {
        throw std::runtime_error("MemlessPoly: invalid number of coefs_am: " +
                std::to_string(n_coefs_am) + " expected " + std::to_string(NUM_COEFS_AM));
    }

    etiLog.log(debug, "MemlessPoly: Reading %d coefs_am...", n_coefs_am);

    coefs_am.resize(n_coefs_am);

    for (int n = 0; n < n_coefs_am; n++) {
        float a;
        coef_fstream_am >> a;
        coefs_am[n] = a;

        if (coef_fstream_am.eof()) {
            etiLog.log(error, "MemlessPoly: file %s should contains %d coefs_am, "
                    "but EOF reached after %d coefs_am !",
                    coefFile_am.c_str(), n_coefs_am, n);
            throw std::runtime_error("MemlessPoly: coefs_am file invalid !");
        }
    }

    {
        std::lock_guard<std::mutex> lock(m_coefs_am_mutex);

        m_coefs_am = coefs_am;
    }
}

void MemlessPoly::load_coefficients_pm(const std::string &coefFile_pm)
{
    std::vector<float> coefs_pm;
    std::ifstream coef_fstream_pm(coefFile_pm.c_str());
    if (!coef_fstream_pm) {
        throw std::runtime_error("MemlessPoly: Could not open file with coefs_pm!");
    }
    int n_coefs_pm;
    coef_fstream_pm >> n_coefs_pm;

    if (n_coefs_pm <= 0) {
        throw std::runtime_error("MemlessPoly: coefs_pm file has invalid format.");
    }
    else if (n_coefs_pm != NUM_COEFS_PM) {
        throw std::runtime_error("MemlessPoly: invalid number of coefs_pm: " +
                std::to_string(n_coefs_pm) + " expected " + std::to_string(NUM_COEFS_PM));
    }

    etiLog.log(debug, "MemlessPoly: Reading %d coefs_pm...", n_coefs_pm);

    coefs_pm.resize(n_coefs_pm);

    for (int n = 0; n < n_coefs_pm; n++) {
        float a;
        coef_fstream_pm >> a;
        coefs_pm[n] = a;

        if (coef_fstream_pm.eof()) {
            etiLog.log(error, "MemlessPoly: file %s should contains %d coefs_pm, "
                    "but EOF reached after %d coefs_pm !",
                    coefFile_pm.c_str(), n_coefs_pm, n);
            throw std::runtime_error("MemlessPoly: coefs_pm file invalid !");
        }
    }

    {
        std::lock_guard<std::mutex> lock(m_coefs_pm_mutex);

        m_coefs_pm = coefs_pm;
    }
}

/* The restrict keyword is C99, g++ and clang++ however support __restrict
 * instead, and this allows the compiler to auto-vectorize the loop.
 */

static void apply_coeff(
        const vector<float> &coefs_am,
        const vector<float> &coefs_pm,
        const complexf *__restrict in, size_t start, size_t stop,
        complexf *__restrict out)
{
    for (size_t i = start; i < stop; i+=1) {

        float in_mag_sq = in[i].real() * in[i].real() + in[i].imag() * in[i].imag();

        float amplitude_correction =
            ( coefs_am[0] + in_mag_sq *
              ( coefs_am[1] + in_mag_sq *
                ( coefs_am[2] + in_mag_sq *
                  ( coefs_am[3] + in_mag_sq *
                    ( coefs_am[4] + in_mag_sq )))));

        float phase_correction = -1 *
            ( coefs_pm[0] + in_mag_sq *
              ( coefs_pm[1] + in_mag_sq *
                ( coefs_pm[2] + in_mag_sq *
                  ( coefs_pm[3] + in_mag_sq *
                    ( coefs_pm[4] + in_mag_sq )))));

        float phase_correction_sq = phase_correction * phase_correction;

        // Approximation for Cosinus 1 - 1/2 x^2 + 1/24 x^4 - 1/720 x^6
        float re = (1.0f - phase_correction_sq *
                ( -0.5f + phase_correction_sq *
                    ( 0.486666f  + phase_correction_sq *
                        ( -0.00138888f))));

        // Approximation for Sinus x + 1/6 x^3 + 1/120 x^5
        float im = phase_correction *
                (1.0f + phase_correction_sq *
                    (0.166666f + phase_correction_sq *
                        (0.00833333f)));

        out[i] = in[i] * amplitude_correction * complex<float>(re, im);
    }
}

int MemlessPoly::internal_process(Buffer* const dataIn, Buffer* dataOut)
{
    dataOut->setLength(dataIn->getLength());

    const complexf* in = reinterpret_cast<const complexf*>(dataIn->getData());
    complexf* out = reinterpret_cast<complexf*>(dataOut->getData());
    size_t sizeOut = dataOut->getLength() / sizeof(complexf);

    {
        std::lock_guard<std::mutex> lock_am(m_coefs_am_mutex);
        std::lock_guard<std::mutex> lock_pm(m_coefs_pm_mutex);
        const unsigned int hw_concurrency = std::thread::hardware_concurrency();

        const unsigned int num_threads =
            (m_num_threads > 0) ? m_num_threads : hw_concurrency;

        if (num_threads) {
            const size_t step = sizeOut / num_threads;
            vector<future<void> > flags;

            size_t start = 0;
            for (size_t i = 0; i < num_threads - 1; i++) {
                flags.push_back(async(launch::async, apply_coeff,
                            m_coefs_am, m_coefs_pm, in, start, start + step, out));

                start += step;
            }

            // Do the last in this thread
            apply_coeff(m_coefs_am, m_coefs_pm, in, start, sizeOut, out);

            // Wait for completion of the tasks
            for (auto& f : flags) {
                f.get();
            }
        }
        else {
            apply_coeff(m_coefs_am, m_coefs_pm, in, 0, sizeOut, out);
        }
    }

    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_am") {
        throw ParameterError("Parameter 'ncoefs_am' is read-only");
    }
    else if (parameter == "ncoefs_pm") {
        throw ParameterError("Parameter 'ncoefs_pm' is read-only");
    }
    else if (parameter == "coeffile_am") {
        try {
            load_coefficients_am(value);
            m_coefs_am_file = value;
        }
        catch (std::runtime_error &e) {
            throw ParameterError(e.what());
        }
    }
    else if (parameter == "coeffile_pm") {
        try {
            load_coefficients_pm(value);
            m_coefs_pm_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_am") {
        ss << m_coefs_am.size();
    }
    else if (parameter == "ncoefs_pm") {
        ss << m_coefs_pm.size();
    }
    else if (parameter == "coefFile_am") {
        ss << m_coefs_am_file;
    }
    else if (parameter == "coefFile_pm") {
        ss << m_coefs_pm_file;
    }
    else {
        ss << "Parameter '" << parameter <<
            "' is not exported by controllable " << get_rc_name();
        throw ParameterError(ss.str());
    }
    return ss.str();
}