AnalogSegment: Calculate min/max also for small sample sizes

diff --git a/pv/data/analogsegment.cpp b/pv/data/analogsegment.cpp
index cfc0f2bb60a9498d9561f10c27b5e22ae84ee896..38db0f123d3be31e95b98ee849fde237bf46819c 100644 (file)
--- a/pv/data/analogsegment.cpp
+++ b/pv/data/analogsegment.cpp
@@ -167,6 +167,18 @@ void AnalogSegment::append_payload_to_envelope_levels()
        prev_length = e0.length;
        e0.length = sample_count_ / EnvelopeScaleFactor;
 
+       // Calculate min/max values in case we have too few samples for an envelope
+       if (sample_count_ < EnvelopeScaleFactor) {
+               it = begin_raw_sample_iteration(0);
+               for (uint64_t i = 0; i < sample_count_; i++) {
+                       const float sample = *((float*)it->value);
+                       if (sample < min_value_) min_value_ = sample;
+                       if (sample > max_value_) max_value_ = sample;
+                       continue_raw_sample_iteration(it, 1);
+               }
+               end_raw_sample_iteration(it);
+       }
+
        // Break off if there are no new samples to compute
        if (e0.length == prev_length)
                return;