]> sigrok.org Git - pulseview.git/blobdiff - pv/data/analogsnapshot.cpp
Make member variable underscores a suffix instead of a prefix
[pulseview.git] / pv / data / analogsnapshot.cpp
index 1658a04c3bfe365138b5ba21f064702e3719e0f7..df3cb42d5b7b511da22ba77056c41f6de5e018be 100644 (file)
 #include <stdlib.h>
 #include <math.h>
 
-#include <boost/foreach.hpp>
+#include <algorithm>
 
 #include "analogsnapshot.h"
 
-using namespace boost;
-using namespace std;
+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 {
 
-AnalogSnapshot::AnalogSnapshot(const sr_datafeed_analog &analog) :
+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(const uint64_t expected_num_samples) :
        Snapshot(sizeof(float))
 {
-       lock_guard<recursive_mutex> lock(_mutex);
-       append_payload(analog);
+       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_payload(
-       const sr_datafeed_analog &analog)
+void AnalogSnapshot::append_interleaved_samples(const float *data,
+       size_t sample_count, size_t stride)
 {
-       lock_guard<recursive_mutex> lock(_mutex);
-       append_data(analog.data, analog.num_samples);
+       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(start_sample < (int64_t)sample_count_);
        assert(end_sample >= 0);
-       assert(end_sample < (int64_t)_sample_count);
+       assert(end_sample < (int64_t)sample_count_);
        assert(start_sample <= end_sample);
 
-       lock_guard<recursive_mutex> lock(_mutex);
+       lock_guard<recursive_mutex> lock(mutex_);
 
        float *const data = new float[end_sample - start_sample];
-       memcpy(data, (float*)_data + start_sample, sizeof(float) *
+       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