#include <stdlib.h>
#include <math.h>
+#include <algorithm>
+
#include <boost/foreach.hpp>
#include "analogsnapshot.h"
-using namespace boost;
-using namespace std;
+using boost::lock_guard;
+using boost::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))
{
+ set_capacity(expected_num_samples);
+
lock_guard<recursive_mutex> lock(_mutex);
- append_payload(analog);
+ memset(_envelope_levels, 0, sizeof(_envelope_levels));
}
-void AnalogSnapshot::append_payload(
- const sr_datafeed_analog &analog)
+AnalogSnapshot::~AnalogSnapshot()
{
lock_guard<recursive_mutex> lock(_mutex);
- append_data(analog.data, analog.num_samples);
+ BOOST_FOREACH(Envelope &e, _envelope_levels)
+ free(e.samples);
}
-const float* AnalogSnapshot::get_samples() const
+void AnalogSnapshot::append_interleaved_samples(const float *data,
+ size_t sample_count, size_t stride)
{
- return (const float*)_data;
+ assert(_unit_size == sizeof(float));
+
+ lock_guard<recursive_mutex> lock(_mutex);
+
+ _data = realloc(_data, (_sample_count + sample_count) * sizeof(float));
+
+ float *dst = (float*)_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 + 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 +
+ e0.length * EnvelopeScaleFactor;
+ for (const float *src_ptr = (float*)_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
projects / pulseview.git / blobdiff