Add --audio-encoder option

Similar to --video-encoder, but for audio.

app/scrcpy.1

@@ -31,6 +31,10 @@ Select an audio codec (opus or aac).
 
 Default is opus.
 
+.TP
+.BI "\-\-audio\-encoder " name
+Use a specific MediaCodec audio encoder (depending on the codec provided by \fB\-\-audio\-codec\fR).
+
 .TP
 .BI "\-b, \-\-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

@@ -61,6 +61,7 @@
 #define OPT_NO_AUDIO               1041
 #define OPT_AUDIO_BIT_RATE         1042
 #define OPT_AUDIO_CODEC            1043
+#define OPT_AUDIO_ENCODER_NAME     1044
 
 struct sc_option {
     char shortopt;
@@ -116,6 +117,13 @@ static const struct sc_option options[] = {
         .text = "Select an audio codec (opus or aac).\n"
                 "Default is opus.",
     },
+    {
+        .longopt_id = OPT_AUDIO_ENCODER_NAME,
+        .longopt = "audio-encoder",
+        .argdesc = "name",
+        .text = "Use a specific MediaCodec audio encoder (depending on the "
+                "codec provided by --audio-codec).",
+    },
     {
         .shortopt = 'b',
         .longopt = "bit-rate",
@@ -1636,6 +1644,9 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             case OPT_ENCODER_NAME:
                 opts->encoder_name = optarg;
                 break;
+            case OPT_AUDIO_ENCODER_NAME:
+                opts->audio_encoder_name = optarg;
+                break;
             case OPT_FORCE_ADB_FORWARD:
                 opts->force_adb_forward = true;
                 break;

app/src/options.h

@@ -97,6 +97,7 @@ struct scrcpy_options {
     const char *render_driver;
     const char *codec_options;
     const char *encoder_name;
+    const char *audio_encoder_name;
 #ifdef HAVE_V4L2
     const char *v4l2_device;
 #endif

app/src/scrcpy.c

@@ -368,6 +368,7 @@ scrcpy(struct scrcpy_options *options) {
         .stay_awake = options->stay_awake,
         .codec_options = options->codec_options,
         .encoder_name = options->encoder_name,
+        .audio_encoder_name = options->audio_encoder_name,
         .force_adb_forward = options->force_adb_forward,
         .power_off_on_close = options->power_off_on_close,
         .clipboard_autosync = options->clipboard_autosync,

app/src/server.c

@@ -73,6 +73,7 @@ sc_server_params_destroy(struct sc_server_params *params) {
     free((char *) params->crop);
     free((char *) params->codec_options);
     free((char *) params->encoder_name);
+    free((char *) params->audio_encoder_name);
     free((char *) params->tcpip_dst);
 }
 
@@ -97,6 +98,7 @@ sc_server_params_copy(struct sc_server_params *dst,
     COPY(crop);
     COPY(codec_options);
     COPY(encoder_name);
+    COPY(audio_encoder_name);
     COPY(tcpip_dst);
 #undef COPY
 
@@ -271,6 +273,9 @@ execute_server(struct sc_server *server,
     if (params->encoder_name) {
         ADD_PARAM("encoder_name=%s", params->encoder_name);
     }
+    if (params->audio_encoder_name) {
+        ADD_PARAM("audio_encoder_name=%s", params->audio_encoder_name);
+    }
     if (params->power_off_on_close) {
         ADD_PARAM("power_off_on_close=true");
     }

app/src/server.h

@@ -30,6 +30,7 @@ struct sc_server_params {
     const char *crop;
     const char *codec_options;
     const char *encoder_name;
+    const char *audio_encoder_name;
     struct sc_port_range port_range;
     uint32_t tunnel_host;
     uint16_t tunnel_port;

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

@@ -46,6 +46,7 @@ public final class AudioEncoder {
 
     private final Streamer streamer;
     private final int bitRate;
+    private final String encoderName;
 
     // 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.
@@ -60,9 +61,10 @@ public final class AudioEncoder {
 
     private boolean ended;
 
-    public AudioEncoder(Streamer streamer, int bitRate) {
+    public AudioEncoder(Streamer streamer, int bitRate, String encoderName) {
         this.streamer = streamer;
         this.bitRate = bitRate;
+        this.encoderName = encoderName;
     }
 
     private static AudioFormat createAudioFormat() {
@@ -210,14 +212,14 @@ public final class AudioEncoder {
         boolean mediaCodecStarted = false;
         boolean recorderStarted = false;
         try {
-            String mimeType = streamer.getCodec().getMimeType();
+            Codec codec = streamer.getCodec();
-            mediaCodec = MediaCodec.createEncoderByType(mimeType); // may throw IOException
+            mediaCodec = createMediaCodec(codec, encoderName);
             recorder = createAudioRecord();
 
             mediaCodecThread = new HandlerThread("AudioEncoder");
             mediaCodecThread.start();
 
-            MediaFormat format = createFormat(mimeType, bitRate);
+            MediaFormat format = createFormat(codec.getMimeType(), bitRate);
             mediaCodec.setCallback(new EncoderCallback(), new Handler(mediaCodecThread.getLooper()));
             mediaCodec.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
 
@@ -257,6 +259,8 @@ public final class AudioEncoder {
             outputThread.start();
 
             waitEnded();
+        } catch (ConfigurationException e) {
+            // Do not print stack trace, a user-friendly error-message has already been logged
         } finally {
             if (!recorderStarted) {
                 // Notify the client that the audio could not be captured
@@ -307,6 +311,21 @@ public final class AudioEncoder {
         }
     }
 
+    private static MediaCodec createMediaCodec(Codec codec, String encoderName) throws IOException, ConfigurationException {
+        if (encoderName != null) {
+            Ln.d("Creating audio encoder by name: '" + encoderName + "'");
+            try {
+                return MediaCodec.createByCodecName(encoderName);
+            } catch (IllegalArgumentException e) {
+                Ln.e(CodecUtils.buildUnknownEncoderMessage(codec, encoderName));
+                throw new ConfigurationException("Unknown encoder: " + encoderName);
+            }
+        }
+        MediaCodec mediaCodec = MediaCodec.createEncoderByType(codec.getMimeType());
+        Ln.d("Using audio encoder: '" + mediaCodec.getName() + "'");
+        return mediaCodec;
+    }
+
     private class EncoderCallback extends MediaCodec.Callback {
         @TargetApi(Build.VERSION_CODES.N)
         @Override

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

@@ -24,6 +24,7 @@ public class Options {
     private boolean stayAwake;
     private List<CodecOption> codecOptions;
     private String encoderName;
+    private String audioEncoderName;
     private boolean powerOffScreenOnClose;
     private boolean clipboardAutosync = true;
     private boolean downsizeOnError = true;
@@ -180,6 +181,14 @@ public class Options {
         this.encoderName = encoderName;
     }
 
+    public String getAudioEncoderName() {
+        return audioEncoderName;
+    }
+
+    public void setAudioEncoderName(String audioEncoderName) {
+        this.audioEncoderName = audioEncoderName;
+    }
+
     public void setPowerOffScreenOnClose(boolean powerOffScreenOnClose) {
         this.powerOffScreenOnClose = powerOffScreenOnClose;
     }

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

@@ -112,7 +112,7 @@ public final class Server {
             if (audio) {
                 Streamer audioStreamer = new Streamer(connection.getAudioFd(), options.getAudioCodec(), options.getSendCodecId(),
                         options.getSendFrameMeta());
-                audioEncoder = new AudioEncoder(audioStreamer, options.getAudioBitRate());
+                audioEncoder = new AudioEncoder(audioStreamer, options.getAudioBitRate(), options.getAudioEncoderName());
                 audioEncoder.start();
             }
 
@@ -264,6 +264,10 @@ public final class Server {
                         options.setEncoderName(value);
                     }
                     break;
+                case "audio_encoder_name":
+                    if (!value.isEmpty()) {
+                        options.setAudioEncoderName(value);
+                    }
                 case "power_off_on_close":
                     boolean powerOffScreenOnClose = Boolean.parseBoolean(value);
                     options.setPowerOffScreenOnClose(powerOffScreenOnClose);