const double start_time = snapshot->start_time();
const int64_t last_sample = snapshot->get_sample_count() - 1;
const double samples_per_pixel = samplerate * pp.scale();
const double start_time = snapshot->start_time();
const int64_t last_sample = snapshot->get_sample_count() - 1;
const double samples_per_pixel = samplerate * pp.scale();