+++ /dev/null
-/*
- * This file is part of the PulseView project.
- *
- * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
- *
- * 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 of the License, 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; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <extdef.h>
-
-#include <assert.h>
-#include <string.h>
-#include <stdlib.h>
-#include <math.h>
-
-#include <algorithm>
-
-#include "analogsnapshot.hpp"
-
-using std::lock_guard;
-using std::recursive_mutex;
-using std::max;
-using std::max_element;
-using std::min;
-using std::min_element;
-
-namespace pv {
-namespace data {
-
-const int AnalogSnapshot::EnvelopeScalePower = 4;
-const int AnalogSnapshot::EnvelopeScaleFactor = 1 << EnvelopeScalePower;
-const float AnalogSnapshot::LogEnvelopeScaleFactor =
- logf(EnvelopeScaleFactor);
-const uint64_t AnalogSnapshot::EnvelopeDataUnit = 64*1024; // bytes
-
-AnalogSnapshot::AnalogSnapshot(
- uint64_t samplerate, const uint64_t expected_num_samples) :
- Snapshot(samplerate, sizeof(float))
-{
- set_capacity(expected_num_samples);
-
- lock_guard<recursive_mutex> lock(mutex_);
- memset(envelope_levels_, 0, sizeof(envelope_levels_));
-}
-
-AnalogSnapshot::~AnalogSnapshot()
-{
- lock_guard<recursive_mutex> lock(mutex_);
- for (Envelope &e : envelope_levels_)
- free(e.samples);
-}
-
-void AnalogSnapshot::append_interleaved_samples(const float *data,
- size_t sample_count, size_t stride)
-{
- assert(unit_size_ == sizeof(float));
-
- lock_guard<recursive_mutex> lock(mutex_);
-
- data_.resize((sample_count_ + sample_count) * sizeof(float));
-
- float *dst = (float*)data_.data() + sample_count_;
- const float *dst_end = dst + sample_count;
- while (dst != dst_end)
- {
- *dst++ = *data;
- data += stride;
- }
-
- sample_count_ += sample_count;
-
- // Generate the first mip-map from the data
- append_payload_to_envelope_levels();
-}
-
-const float* AnalogSnapshot::get_samples(
- int64_t start_sample, int64_t end_sample) const
-{
- assert(start_sample >= 0);
- assert(start_sample < (int64_t)sample_count_);
- assert(end_sample >= 0);
- assert(end_sample < (int64_t)sample_count_);
- assert(start_sample <= end_sample);
-
- lock_guard<recursive_mutex> lock(mutex_);
-
- float *const data = new float[end_sample - start_sample];
- memcpy(data, (float*)data_.data() + start_sample, sizeof(float) *
- (end_sample - start_sample));
- return data;
-}
-
-void AnalogSnapshot::get_envelope_section(EnvelopeSection &s,
- uint64_t start, uint64_t end, float min_length) const
-{
- assert(end <= get_sample_count());
- assert(start <= end);
- assert(min_length > 0);
-
- lock_guard<recursive_mutex> lock(mutex_);
-
- const unsigned int min_level = max((int)floorf(logf(min_length) /
- LogEnvelopeScaleFactor) - 1, 0);
- const unsigned int scale_power = (min_level + 1) *
- EnvelopeScalePower;
- start >>= scale_power;
- end >>= scale_power;
-
- s.start = start << scale_power;
- s.scale = 1 << scale_power;
- s.length = end - start;
- s.samples = new EnvelopeSample[s.length];
- memcpy(s.samples, envelope_levels_[min_level].samples + start,
- s.length * sizeof(EnvelopeSample));
-}
-
-void AnalogSnapshot::reallocate_envelope(Envelope &e)
-{
- const uint64_t new_data_length = ((e.length + EnvelopeDataUnit - 1) /
- EnvelopeDataUnit) * EnvelopeDataUnit;
- if (new_data_length > e.data_length)
- {
- e.data_length = new_data_length;
- e.samples = (EnvelopeSample*)realloc(e.samples,
- new_data_length * sizeof(EnvelopeSample));
- }
-}
-
-void AnalogSnapshot::append_payload_to_envelope_levels()
-{
- Envelope &e0 = envelope_levels_[0];
- uint64_t prev_length;
- EnvelopeSample *dest_ptr;
-
- // Expand the data buffer to fit the new samples
- prev_length = e0.length;
- e0.length = sample_count_ / EnvelopeScaleFactor;
-
- // Break off if there are no new samples to compute
- if (e0.length == prev_length)
- return;
-
- reallocate_envelope(e0);
-
- dest_ptr = e0.samples + prev_length;
-
- // Iterate through the samples to populate the first level mipmap
- const float *const end_src_ptr = (float*)data_.data() +
- e0.length * EnvelopeScaleFactor;
- for (const float *src_ptr = (float*)data_.data() +
- prev_length * EnvelopeScaleFactor;
- src_ptr < end_src_ptr; src_ptr += EnvelopeScaleFactor)
- {
- const EnvelopeSample sub_sample = {
- *min_element(src_ptr, src_ptr + EnvelopeScaleFactor),
- *max_element(src_ptr, src_ptr + EnvelopeScaleFactor),
- };
-
- *dest_ptr++ = sub_sample;
- }
-
- // Compute higher level mipmaps
- for (unsigned int level = 1; level < ScaleStepCount; level++)
- {
- Envelope &e = envelope_levels_[level];
- const Envelope &el = envelope_levels_[level-1];
-
- // Expand the data buffer to fit the new samples
- prev_length = e.length;
- e.length = el.length / EnvelopeScaleFactor;
-
- // Break off if there are no more samples to computed
- if (e.length == prev_length)
- break;
-
- reallocate_envelope(e);
-
- // Subsample the level lower level
- const EnvelopeSample *src_ptr =
- el.samples + prev_length * EnvelopeScaleFactor;
- const EnvelopeSample *const end_dest_ptr = e.samples + e.length;
- for (dest_ptr = e.samples + prev_length;
- dest_ptr < end_dest_ptr; dest_ptr++)
- {
- const EnvelopeSample *const end_src_ptr =
- src_ptr + EnvelopeScaleFactor;
-
- EnvelopeSample sub_sample = *src_ptr++;
- while (src_ptr < end_src_ptr)
- {
- sub_sample.min = min(sub_sample.min, src_ptr->min);
- sub_sample.max = max(sub_sample.max, src_ptr->max);
- src_ptr++;
- }
-
- *dest_ptr = sub_sample;
- }
- }
-}
-
-} // namespace data
-} // namespace pv
projects / pulseview.git / blobdiff