Fix audio PTS when not monotonically increasing

Some decoders fail to guarantee that PTS must be monotonically
increasing. Fix the PTS when they're not.

Fixes #4054 <https://github.com/Genymobile/scrcpy/issues/4054>

app/src/cli.c

@@ -77,7 +77,6 @@ enum {
     OPT_NO_AUDIO_PLAYBACK,
     OPT_NO_VIDEO_PLAYBACK,
     OPT_AUDIO_SOURCE,
-    OPT_NO_KILL_ADB_BEFORE_OTG,
 };
 
 struct sc_option {
@@ -412,16 +411,6 @@ static const struct sc_option options[] = {
         .longopt = "no-key-repeat",
         .text = "Do not forward repeated key events when a key is held down.",
     },
-    {
-        .longopt_id = OPT_NO_KILL_ADB_BEFORE_OTG,
-        .longopt = "no-kill-adb-before-otg",
-        // with .text, the option is not documented on other platforms
-#ifdef _WIN32
-        .text = "By default, scrcpy kills the adb daemon on Windows if --otg "
-                "is specified.\n"
-                "This option avoids to kill the adb daemon.",
-#endif
-    },
     {
         .longopt_id = OPT_NO_MIPMAPS,
         .longopt = "no-mipmaps",
@@ -1955,14 +1944,6 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
                     return false;
                 }
                 break;
-            case OPT_NO_KILL_ADB_BEFORE_OTG:
-#ifdef _WIN32
-                opts->kill_adb_before_otg = false;
-                break;
-#else
-                LOGE("--no-kill-adb-before-otg only exists on Windows.");
-                return false;
-#endif
             default:
                 // getopt prints the error message on stderr
                 return false;

app/src/options.c

@@ -48,9 +48,6 @@ const struct scrcpy_options scrcpy_options_default = {
 #endif
 #ifdef HAVE_USB
     .otg = false,
-#endif
-#ifdef _WIN32
-    .kill_adb_before_otg = true,
 #endif
     .show_touches = false,
     .fullscreen = false,

app/src/options.h

@@ -148,9 +148,6 @@ struct scrcpy_options {
 #endif
 #ifdef HAVE_USB
     bool otg;
-#endif
-#ifdef _WIN32
-    bool kill_adb_before_otg;
 #endif
     bool show_touches;
     bool fullscreen;

app/src/usb/scrcpy_otg.c

@@ -83,12 +83,10 @@ scrcpy_otg(struct scrcpy_options *options) {
 #ifdef _WIN32
     // On Windows, only one process could open a USB device
     // <https://github.com/Genymobile/scrcpy/issues/2773>
-    if (options->kill_adb_before_otg) {
-        LOGI("Killing adb daemon (if any)...");
-        unsigned flags = SC_ADB_NO_STDOUT | SC_ADB_NO_STDERR | SC_ADB_NO_LOGERR;
-        // uninterruptible (intr == NULL), but in practice it's very quick
-        sc_adb_kill_server(NULL, flags);
-    }
+    LOGI("Killing adb daemon (if any)...");
+    unsigned flags = SC_ADB_NO_STDOUT | SC_ADB_NO_STDERR | SC_ADB_NO_LOGERR;
+    // uninterruptible (intr == NULL), but in practice it's very quick
+    sc_adb_kill_server(NULL, flags);
 #endif
 
     static const struct sc_usb_callbacks cbs = {

doc/audio.md

@@ -30,8 +30,9 @@ To disable only the audio playback, see [no playback](video.md#no-playback).
 
 To play audio only, disable the video:
 
-```
+```bash
 scrcpy --no-video
+# interrupt with Ctrl+C
 ```
 
 Without video, the audio latency is typically not criticial, so it might be

doc/video.md

@@ -168,6 +168,7 @@ the computer. This option is useful when [recording](recording.md) or when
 ```bash
 scrcpy --v4l2-sink=/dev/video2 --no-playback
 scrcpy --record=file.mkv --no-playback
+# interrupt with Ctrl+C
 ```
 
 It is also possible to disable video and audio playback separately:

server/src/main/java/com/genymobile/scrcpy/AudioCapture.java

@@ -163,7 +163,7 @@ public final class AudioCapture {
             //  - an estimation from the previous PTS and the packet size as a fallback.
             //
             // Therefore, the property that PTS are monotonically increasing is no guaranteed in corner cases, so enforce it.
-            pts = previousPts + 1;
+            pts = previousPts;
         }
         previousPts = pts;
 

server/src/main/java/com/genymobile/scrcpy/AudioEncoder.java

@@ -105,8 +105,17 @@ public final class AudioEncoder implements AsyncProcessor {
     private void outputThread(MediaCodec mediaCodec) throws IOException, InterruptedException {
         streamer.writeAudioHeader();
 
+        long lastPts = 0;
         while (!Thread.currentThread().isInterrupted()) {
             OutputTask task = outputTasks.take();
+
+            if (task.bufferInfo.presentationTimeUs < lastPts) {
+                // Fix PTS if not monotonically increasing
+                task.bufferInfo.presentationTimeUs = lastPts;
+            } else {
+                lastPts = task.bufferInfo.presentationTimeUs;
+            }
+
             ByteBuffer buffer = mediaCodec.getOutputBuffer(task.index);
             try {
                 streamer.writePacket(buffer, task.bufferInfo);