On first input, special-case too large queue, not just too small.

Fixes problems with low delay and an output timer that starts pretty
slowly (e.g. the HDMI/SDI output timer).

diff --git a/resampling_queue.cpp b/resampling_queue.cpp
index 188bf7d2d57ccdb98f249f86c59e0360e65b470b..d7e811d87c4bd4bb7b1325c2e262a5fedbf0cc71 100644 (file)
--- a/resampling_queue.cpp
+++ b/resampling_queue.cpp
@@ -93,15 +93,24 @@ bool ResamplingQueue::get_output_samples(steady_clock::time_point ts, float *sam
                double actual_delay = input_samples_received - input_samples_consumed;
                actual_delay += vresampler.inpdist();    // Delay in the resampler itself.
                double err = actual_delay - expected_delay;
-               if (first_output && err < 0.0) {
+               if (first_output) {
                        // Before the very first block, insert artificial delay based on our initial estimate,
                        // so that we don't need a long period to stabilize at the beginning.
-                       int delay_samples_to_add = lrintf(-err);
-                       for (ssize_t i = 0; i < delay_samples_to_add * num_channels; ++i) {
-                               buffer.push_front(0.0f);
+                       if (err < 0.0) {
+                               int delay_samples_to_add = lrintf(-err);
+                               for (ssize_t i = 0; i < delay_samples_to_add * num_channels; ++i) {
+                                       buffer.push_front(0.0f);
+                               }
+                               total_consumed_samples -= delay_samples_to_add;  // Equivalent to increasing input_samples_received on a0 and a1.
+                               err += delay_samples_to_add;
+                       } else if (err > 0.0) {
+                               int delay_samples_to_remove = min<int>(lrintf(err), buffer.size() / num_channels);
+                               for (ssize_t i = 0; i < delay_samples_to_remove * num_channels; ++i) {
+                                       buffer.pop_front();
+                               }
+                               total_consumed_samples += delay_samples_to_remove;
+                               err -= delay_samples_to_remove;
                        }
-                       total_consumed_samples -= delay_samples_to_add;  // Equivalent to increasing input_samples_received on a0 and a1.
-                       err += delay_samples_to_add;
                }
                first_output = false;