Add --audio-bit-rate

Add an option to configure the audio bit-rate.

PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>

app/data/bash-completion/scrcpy

@@ -2,6 +2,7 @@ _scrcpy() {
     local cur prev words cword
     local opts="
         --always-on-top
+        --audio-bit-rate=
         -b --video-bit-rate=
         --crop=
         -d --select-usb

app/data/zsh-completion/_scrcpy

@@ -9,6 +9,7 @@ local arguments
 
 arguments=(
     '--always-on-top[Make scrcpy window always on top \(above other windows\)]'
+    '--audio-bit-rate=[Encode the audio at the given bit-rate]'
     {-b,--video-bit-rate=}'[Encode the video at the given bit-rate]'
     '--crop=[\[width\:height\:x\:y\] Crop the device screen on the server]'
     {-d,--select-usb}'[Use USB device]'

app/scrcpy.1

@@ -19,6 +19,12 @@ provides display and control of Android devices connected on USB (or over TCP/IP
 .B \-\-always\-on\-top
 Make scrcpy window always on top (above other windows).
 
+.TP
+.BI "\-\-audio\-bit\-rate " value
+Encode the audio at the given bit\-rate, expressed in bits/s. Unit suffixes are supported: '\fBK\fR' (x1000) and '\fBM\fR' (x1000000).
+
+Default is 128K (128000).
+
 .TP
 .BI "\-b, \-\-video\-bit\-rate " value
 Encode the video at the given bit\-rate, expressed in bits/s. Unit suffixes are supported: '\fBK\fR' (x1000) and '\fBM\fR' (x1000000).

app/src/cli.c

@@ -64,6 +64,7 @@ enum {
     OPT_CODEC,
     OPT_VIDEO_CODEC,
     OPT_NO_AUDIO,
+    OPT_AUDIO_BIT_RATE,
 };
 
 struct sc_option {
@@ -105,6 +106,14 @@ static const struct sc_option options[] = {
         .longopt = "always-on-top",
         .text = "Make scrcpy window always on top (above other windows).",
     },
+    {
+        .longopt_id = OPT_AUDIO_BIT_RATE,
+        .longopt = "audio-bit-rate",
+        .argdesc = "value",
+        .text = "Encode the audio at the given bit-rate, expressed in bits/s. "
+                "Unit suffixes are supported: 'K' (x1000) and 'M' (x1000000).\n"
+                "Default is 128K (128000).",
+    },
     {
         .shortopt = 'b',
         .longopt = "video-bit-rate",
@@ -1461,6 +1470,11 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
                     return false;
                 }
                 break;
+            case OPT_AUDIO_BIT_RATE:
+                if (!parse_bit_rate(optarg, &opts->audio_bit_rate)) {
+                    return false;
+                }
+                break;
             case OPT_CROP:
                 opts->crop = optarg;
                 break;

app/src/options.c

@@ -29,6 +29,7 @@ const struct scrcpy_options scrcpy_options_default = {
     },
     .max_size = 0,
     .video_bit_rate = 0,
+    .audio_bit_rate = 0,
     .max_fps = 0,
     .lock_video_orientation = SC_LOCK_VIDEO_ORIENTATION_UNLOCKED,
     .rotation = 0,

app/src/options.h

@@ -109,6 +109,7 @@ struct scrcpy_options {
     struct sc_shortcut_mods shortcut_mods;
     uint16_t max_size;
     uint32_t video_bit_rate;
+    uint32_t audio_bit_rate;
     uint16_t max_fps;
     enum sc_lock_video_orientation lock_video_orientation;
     uint8_t rotation;

app/src/scrcpy.c

@@ -321,6 +321,7 @@ scrcpy(struct scrcpy_options *options) {
         .tunnel_port = options->tunnel_port,
         .max_size = options->max_size,
         .video_bit_rate = options->video_bit_rate,
+        .audio_bit_rate = options->audio_bit_rate,
         .max_fps = options->max_fps,
         .lock_video_orientation = options->lock_video_orientation,
         .control = options->control,

app/src/server.c

@@ -221,6 +221,8 @@ execute_server(struct sc_server *server,
     }
     if (!params->audio) {
         ADD_PARAM("audio=false");
+    } else if (params->audio_bit_rate) {
+        ADD_PARAM("audio_bit_rate=%" PRIu32, params->audio_bit_rate);
     }
     if (params->video_codec != SC_CODEC_H264) {
         ADD_PARAM("video_codec=%s",

app/src/server.h

@@ -34,6 +34,7 @@ struct sc_server_params {
     uint16_t tunnel_port;
     uint16_t max_size;
     uint32_t video_bit_rate;
+    uint32_t audio_bit_rate;
     uint16_t max_fps;
     int8_t lock_video_orientation;
     bool control;

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

@@ -44,12 +44,12 @@ public final class AudioEncoder {
     private static final int CHANNELS = 2;
     private static final int FORMAT = AudioFormat.ENCODING_PCM_16BIT;
     private static final int BYTES_PER_SAMPLE = 2;
-    private static final int BIT_RATE = 128000;
 
     private static final int READ_MS = 5; // milliseconds
     private static final int READ_SIZE = SAMPLE_RATE * CHANNELS * BYTES_PER_SAMPLE * READ_MS / 1000;
 
     private final Streamer streamer;
+    private final int bitRate;
 
     // Capacity of 64 is in practice "infinite" (it is limited by the number of available MediaCodec buffers, typically 4).
     // So many pending tasks would lead to an unacceptable delay anyway.
@@ -64,8 +64,9 @@ public final class AudioEncoder {
 
     private boolean ended;
 
-    public AudioEncoder(Streamer streamer) {
+    public AudioEncoder(Streamer streamer, int bitRate) {
         this.streamer = streamer;
+        this.bitRate = bitRate;
     }
 
     private static AudioFormat createAudioFormat() {
@@ -92,10 +93,10 @@ public final class AudioEncoder {
         return builder.build();
     }
 
-    private static MediaFormat createFormat() {
+    private static MediaFormat createFormat(int bitRate) {
         MediaFormat format = new MediaFormat();
         format.setString(MediaFormat.KEY_MIME, MIMETYPE);
-        format.setInteger(MediaFormat.KEY_BIT_RATE, BIT_RATE);
+        format.setInteger(MediaFormat.KEY_BIT_RATE, bitRate);
         format.setInteger(MediaFormat.KEY_CHANNEL_COUNT, CHANNELS);
         format.setInteger(MediaFormat.KEY_SAMPLE_RATE, SAMPLE_RATE);
         return format;
@@ -220,7 +221,7 @@ public final class AudioEncoder {
             mediaCodecThread = new HandlerThread("AudioEncoder");
             mediaCodecThread.start();
 
-            MediaFormat format = createFormat();
+            MediaFormat format = createFormat(bitRate);
             mediaCodec.setCallback(new EncoderCallback(), new Handler(mediaCodecThread.getLooper()));
             mediaCodec.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
 

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

@@ -12,6 +12,7 @@ public class Options {
     private int maxSize;
     private VideoCodec videoCodec = VideoCodec.H264;
     private int videoBitRate = 8000000;
+    private int audioBitRate = 128000;
     private int maxFps;
     private int lockVideoOrientation = -1;
     private boolean tunnelForward;
@@ -82,6 +83,14 @@ public class Options {
         this.videoBitRate = videoBitRate;
     }
 
+    public int getAudioBitRate() {
+        return audioBitRate;
+    }
+
+    public void setAudioBitRate(int audioBitRate) {
+        this.audioBitRate = audioBitRate;
+    }
+
     public int getMaxFps() {
         return maxFps;
     }

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

@@ -110,7 +110,7 @@ public final class Server {
 
             if (audio) {
                 Streamer audioStreamer = new Streamer(connection.getAudioFd(), AudioCodec.OPUS, options.getSendCodecId(), options.getSendFrameMeta());
-                audioEncoder = new AudioEncoder(audioStreamer);
+                audioEncoder = new AudioEncoder(audioStreamer, options.getAudioBitRate());
                 audioEncoder.start();
             }
 
@@ -210,6 +210,10 @@ public final class Server {
                     int videoBitRate = Integer.parseInt(value);
                     options.setVideoBitRate(videoBitRate);
                     break;
+                case "audio_bit_rate":
+                    int audioBitRate = Integer.parseInt(value);
+                    options.setAudioBitRate(audioBitRate);
+                    break;
                 case "max_fps":
                     int maxFps = Integer.parseInt(value);
                     options.setMaxFps(maxFps);