Back off PCM reserve probes after starvation and exclude output pauses

tools/chatgui/src/voice_playback_buffer.h

@@ -9,21 +9,23 @@ class VoicePlaybackBuffer {
 public:
     unsigned blocks = 2;
     unsigned callbackFrames = 960;
-    void reset() { blocks = 2; callbackFrames = 960; stableSince = 0; lastGrowth = 0; }
+    void reset() { blocks = 2; callbackFrames = 960; stableSince = 0; lastGrowth = 0; lastSample = 0; probeUs = 10000000; }
     void sample(int64_t nowUs, unsigned frames, bool missing) {
         callbackFrames = frames;
         unsigned minimum = std::clamp((frames + 959) / 960, 1u, 4u);
-        if (!stableSince) stableSince = nowUs;
+        if (!stableSince || nowUs - lastSample > 1000000) stableSince = nowUs;
+        lastSample = nowUs;
         if (minimum > blocks) { blocks = minimum; stableSince = nowUs; }
         if (missing) {
             stableSince = nowUs;
             if (!lastGrowth || nowUs - lastGrowth >= 500000) {
                 blocks = std::min(blocks + 1, 4u); lastGrowth = nowUs;
+                probeUs = std::min(probeUs * 2, int64_t(300000000));
             }
-        } else if (blocks > minimum && nowUs - stableSince >= 10000000) {
+        } else if (blocks > minimum && nowUs - stableSince >= probeUs) {
             --blocks; stableSince = nowUs;
         }
     }
 private:
-    int64_t stableSince = 0, lastGrowth = 0;
+    int64_t stableSince = 0, lastGrowth = 0, lastSample = 0, probeUs = 10000000;
 };

tools/chatgui/tests/test_voice_audio_io.cpp

@@ -78,15 +78,20 @@ int main() {
     // Резерв уменьшается только при стабильной работе; крупный callback и starvation повышают минимум.
     VoicePlaybackBuffer buffering;
     buffering.sample(1, 512, false);
-    buffering.sample(10000000, 512, false); REQUIRE(buffering.blocks == 2);
+    for (int64_t t = 1000000; t <= 10000000; t += 1000000) buffering.sample(t, 512, false);
+    REQUIRE(buffering.blocks == 2);
     buffering.sample(10000001, 512, false); REQUIRE(buffering.blocks == 1);
     buffering.sample(10020001, 512, true); REQUIRE(buffering.blocks == 2);
     buffering.sample(10020002, 512, true); REQUIRE(buffering.blocks == 2);
     buffering.sample(10520001, 512, true); REQUIRE(buffering.blocks == 3);
-    buffering.sample(20520001, 2048, false); REQUIRE(buffering.blocks == 3);
-    buffering.sample(30520001, 512, false); REQUIRE(buffering.blocks == 2);
-    buffering.sample(40520001, 512, false); REQUIRE(buffering.blocks == 1);
+    for (int64_t t = 11520001; t <= 50520001; t += 1000000) buffering.sample(t, 2048, false);
+    REQUIRE(buffering.blocks == 3);
+    buffering.sample(50520002, 512, false); REQUIRE(buffering.blocks == 2);
+    for (int64_t t = 51520002; t <= 90520002; t += 1000000) buffering.sample(t, 512, false);
+    REQUIRE(buffering.blocks == 1);
     buffering.reset(); REQUIRE(buffering.blocks == 2);
+    buffering.sample(1, 512, false);
+    buffering.sample(20000001, 512, false); REQUIRE(buffering.blocks == 2); // Пауза не означает стабильный вывод.
     // Десять минут +/-300ppm дрейфа: связь с физическим временем сохраняется, шага >2мс нет.
     for (double drift : {-0.0003, 0.0003}) {
         VoiceCaptureClock clock;