pv/data/analogsegment.cpp

   1 /*
   2  * This file is part of the PulseView project.
   3  *
   4  * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <extdef.h>
  21
  22 #include <cassert>
  23 #include <cmath>
  24 #include <cstdlib>
  25 #include <cstring>
  26 #include <memory>
  27
  28 #include <algorithm>
  29
  30 #include "analog.hpp"
  31 #include "analogsegment.hpp"
  32
  33 using std::lock_guard;
  34 using std::recursive_mutex;
  35 using std::make_pair;
  36 using std::max;
  37 using std::max_element;
  38 using std::min;
  39 using std::min_element;
  40 using std::pair;
  41 using std::unique_ptr;
  42
  43 namespace pv {
  44 namespace data {
  45
  46 const int AnalogSegment::EnvelopeScalePower = 4;
  47 const int AnalogSegment::EnvelopeScaleFactor = 1 << EnvelopeScalePower;
  48 const float AnalogSegment::LogEnvelopeScaleFactor = logf(EnvelopeScaleFactor);
  49 const uint64_t AnalogSegment::EnvelopeDataUnit = 64 * 1024;     // bytes
  50
  51 AnalogSegment::AnalogSegment(Analog& owner, uint64_t samplerate) :
  52         Segment(samplerate, sizeof(float)),
  53         owner_(owner),
  54         min_value_(0),
  55         max_value_(0)
  56 {
  57         lock_guard<recursive_mutex> lock(mutex_);
  58         memset(envelope_levels_, 0, sizeof(envelope_levels_));
  59 }
  60
  61 AnalogSegment::~AnalogSegment()
  62 {
  63         lock_guard<recursive_mutex> lock(mutex_);
  64         for (Envelope &e : envelope_levels_)
  65                 free(e.samples);
  66 }
  67
  68 void AnalogSegment::append_interleaved_samples(const float *data,
  69         size_t sample_count, size_t stride)
  70 {
  71         assert(unit_size_ == sizeof(float));
  72
  73         lock_guard<recursive_mutex> lock(mutex_);
  74
  75         uint64_t prev_sample_count = sample_count_;
  76
  77         // Deinterleave the samples and add them
  78         unique_ptr<float> deint_data(new float[sample_count]);
  79         float *deint_data_ptr = deint_data.get();
  80         for (uint32_t i = 0; i < sample_count; i++) {
  81                 *deint_data_ptr = (float)(*data);
  82                 deint_data_ptr++;
  83                 data += stride;
  84         }
  85
  86         append_samples(deint_data.get(), sample_count);
  87
  88         // Generate the first mip-map from the data
  89         append_payload_to_envelope_levels();
  90
  91         if (sample_count > 1)
  92                 owner_.notify_samples_added(this, prev_sample_count + 1,
  93                         prev_sample_count + 1 + sample_count);
  94         else
  95                 owner_.notify_samples_added(this, prev_sample_count + 1,
  96                         prev_sample_count + 1);
  97 }
  98
  99 const float* AnalogSegment::get_samples(
 100         int64_t start_sample, int64_t end_sample) const
 101 {
 102         assert(start_sample >= 0);
 103         assert(start_sample < (int64_t)sample_count_);
 104         assert(end_sample >= 0);
 105         assert(end_sample < (int64_t)sample_count_);
 106         assert(start_sample <= end_sample);
 107
 108         lock_guard<recursive_mutex> lock(mutex_);
 109
 110         return (float*)get_raw_samples(start_sample, (end_sample - start_sample));
 111 }
 112
 113 const pair<float, float> AnalogSegment::get_min_max() const
 114 {
 115         return make_pair(min_value_, max_value_);
 116 }
 117
 118 SegmentAnalogDataIterator* AnalogSegment::begin_sample_iteration(uint64_t start)
 119 {
 120         return (SegmentAnalogDataIterator*)begin_raw_sample_iteration(start);
 121 }
 122
 123 void AnalogSegment::continue_sample_iteration(SegmentAnalogDataIterator* it, uint64_t increase)
 124 {
 125         Segment::continue_raw_sample_iteration((SegmentRawDataIterator*)it, increase);
 126 }
 127
 128 void AnalogSegment::end_sample_iteration(SegmentAnalogDataIterator* it)
 129 {
 130         Segment::end_raw_sample_iteration((SegmentRawDataIterator*)it);
 131 }
 132
 133 void AnalogSegment::get_envelope_section(EnvelopeSection &s,
 134         uint64_t start, uint64_t end, float min_length) const
 135 {
 136         assert(end <= get_sample_count());
 137         assert(start <= end);
 138         assert(min_length > 0);
 139
 140         lock_guard<recursive_mutex> lock(mutex_);
 141
 142         const unsigned int min_level = max((int)floorf(logf(min_length) /
 143                 LogEnvelopeScaleFactor) - 1, 0);
 144         const unsigned int scale_power = (min_level + 1) *
 145                 EnvelopeScalePower;
 146         start >>= scale_power;
 147         end >>= scale_power;
 148
 149         s.start = start << scale_power;
 150         s.scale = 1 << scale_power;
 151         s.length = end - start;
 152         s.samples = new EnvelopeSample[s.length];
 153         memcpy(s.samples, envelope_levels_[min_level].samples + start,
 154                 s.length * sizeof(EnvelopeSample));
 155 }
 156
 157 void AnalogSegment::reallocate_envelope(Envelope &e)
 158 {
 159         const uint64_t new_data_length = ((e.length + EnvelopeDataUnit - 1) /
 160                 EnvelopeDataUnit) * EnvelopeDataUnit;
 161         if (new_data_length > e.data_length) {
 162                 e.data_length = new_data_length;
 163                 e.samples = (EnvelopeSample*)realloc(e.samples,
 164                         new_data_length * sizeof(EnvelopeSample));
 165         }
 166 }
 167
 168 void AnalogSegment::append_payload_to_envelope_levels()
 169 {
 170         Envelope &e0 = envelope_levels_[0];
 171         uint64_t prev_length;
 172         EnvelopeSample *dest_ptr;
 173         SegmentRawDataIterator* it;
 174
 175         // Expand the data buffer to fit the new samples
 176         prev_length = e0.length;
 177         e0.length = sample_count_ / EnvelopeScaleFactor;
 178
 179         // Calculate min/max values in case we have too few samples for an envelope
 180         if (sample_count_ < EnvelopeScaleFactor) {
 181                 it = begin_raw_sample_iteration(0);
 182                 for (uint64_t i = 0; i < sample_count_; i++) {
 183                         const float sample = *((float*)it->value);
 184                         if (sample < min_value_)
 185                                 min_value_ = sample;
 186                         if (sample > max_value_)
 187                                 max_value_ = sample;
 188                         continue_raw_sample_iteration(it, 1);
 189                 }
 190                 end_raw_sample_iteration(it);
 191         }
 192
 193         // Break off if there are no new samples to compute
 194         if (e0.length == prev_length)
 195                 return;
 196
 197         reallocate_envelope(e0);
 198
 199         dest_ptr = e0.samples + prev_length;
 200
 201         // Iterate through the samples to populate the first level mipmap
 202         uint64_t start_sample = prev_length * EnvelopeScaleFactor;
 203         uint64_t end_sample = e0.length * EnvelopeScaleFactor;
 204
 205         it = begin_raw_sample_iteration(start_sample);
 206         for (uint64_t i = start_sample; i < end_sample; i += EnvelopeScaleFactor) {
 207                 const float* samples = (float*)it->value;
 208
 209                 const EnvelopeSample sub_sample = {
 210                         *min_element(samples, samples + EnvelopeScaleFactor),
 211                         *max_element(samples, samples + EnvelopeScaleFactor),
 212                 };
 213
 214                 if (sub_sample.min < min_value_)
 215                         min_value_ = sub_sample.min;
 216                 if (sub_sample.max > max_value_)
 217                         max_value_ = sub_sample.max;
 218
 219                 continue_raw_sample_iteration(it, EnvelopeScaleFactor);
 220                 *dest_ptr++ = sub_sample;
 221         }
 222         end_raw_sample_iteration(it);
 223
 224         // Compute higher level mipmaps
 225         for (unsigned int level = 1; level < ScaleStepCount; level++) {
 226                 Envelope &e = envelope_levels_[level];
 227                 const Envelope &el = envelope_levels_[level - 1];
 228
 229                 // Expand the data buffer to fit the new samples
 230                 prev_length = e.length;
 231                 e.length = el.length / EnvelopeScaleFactor;
 232
 233                 // Break off if there are no more samples to be computed
 234                 if (e.length == prev_length)
 235                         break;
 236
 237                 reallocate_envelope(e);
 238
 239                 // Subsample the lower level
 240                 const EnvelopeSample *src_ptr =
 241                         el.samples + prev_length * EnvelopeScaleFactor;
 242                 const EnvelopeSample *const end_dest_ptr = e.samples + e.length;
 243
 244                 for (dest_ptr = e.samples + prev_length;
 245                                 dest_ptr < end_dest_ptr; dest_ptr++) {
 246                         const EnvelopeSample *const end_src_ptr =
 247                                 src_ptr + EnvelopeScaleFactor;
 248
 249                         EnvelopeSample sub_sample = *src_ptr++;
 250                         while (src_ptr < end_src_ptr) {
 251                                 sub_sample.min = min(sub_sample.min, src_ptr->min);;
 252                                 sub_sample.max = max(sub_sample.max, src_ptr->max);
 253                                 src_ptr++;
 254                         }
 255
 256                         *dest_ptr = sub_sample;
 257                 }
 258         }
 259 }
 260
 261 } // namespace data
 262 } // namespace pv