Add --codec-options

Add a command-line parameter to pass custom options to the device
encoder (as a comma-separated list of "key[:type]=value").

The list of possible codec options is available in the Android
documentation:
<https://d.android.com/reference/android/media/MediaFormat>

PR #1325 <https://github.com/Genymobile/scrcpy/pull/1325>
Refs #1226 <https://github.com/Genymobile/scrcpy/pull/1226>

Co-authored-by: Romain Vimont <rom@rom1v.com>

app/scrcpy.1

@@ -25,6 +25,16 @@ Encode the video at the given bit\-rate, expressed in bits/s. Unit suffixes are
 
 Default is 8000000.
 
+.TP
+.BI "\-\-codec\-options " key[:type]=value[,...]
+Set a list of comma-separated key:type=value options for the device encoder.
+
+The possible values for 'type' are 'int' (default), 'long', 'float' and 'string'.
+
+The list of possible codec options is available in the Android documentation
+.UR https://d.android.com/reference/android/media/MediaFormat
+.UE .
+
 .TP
 .BI "\-\-crop " width\fR:\fIheight\fR:\fIx\fR:\fIy
 Crop the device screen on the server.

app/src/cli.c

@@ -30,6 +30,15 @@ scrcpy_print_usage(const char *arg0) {
         "        Unit suffixes are supported: 'K' (x1000) and 'M' (x1000000).\n"
         "        Default is %d.\n"
         "\n"
+        "    --codec-options key[:type]=value[,...]\n"
+        "        Set a list of comma-separated key:type=value options for the\n"
+        "        device encoder.\n"
+        "        The possible values for 'type' are 'int' (default), 'long',\n"
+        "        'float' and 'string'.\n"
+        "        The list of possible codec options is available in the\n"
+        "        Android documentation:\n"
+        "        <https://d.android.com/reference/android/media/MediaFormat>\n"
+        "\n"
         "    --crop width:height:x:y\n"
         "        Crop the device screen on the server.\n"
         "        The values are expressed in the device natural orientation\n"
@@ -472,12 +481,14 @@ guess_record_format(const char *filename) {
 #define OPT_ROTATION               1015
 #define OPT_RENDER_DRIVER          1016
 #define OPT_NO_MIPMAPS             1017
+#define OPT_CODEC_OPTIONS          1018
 
 bool
 scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
     static const struct option long_options[] = {
         {"always-on-top",          no_argument,       NULL, OPT_ALWAYS_ON_TOP},
         {"bit-rate",               required_argument, NULL, 'b'},
+        {"codec-options",          required_argument, NULL, OPT_CODEC_OPTIONS},
         {"crop",                   required_argument, NULL, OPT_CROP},
         {"display",                required_argument, NULL, OPT_DISPLAY_ID},
         {"fullscreen",             no_argument,       NULL, 'f'},
@@ -647,6 +658,9 @@ scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
             case OPT_NO_MIPMAPS:
                 opts->mipmaps = false;
                 break;
+            case OPT_CODEC_OPTIONS:
+                opts->codec_options = optarg;
+                break;
             default:
                 // getopt prints the error message on stderr
                 return false;

app/src/scrcpy.c

@@ -303,6 +303,7 @@ scrcpy(const struct scrcpy_options *options) {
         .display_id = options->display_id,
         .show_touches = options->show_touches,
         .stay_awake = options->stay_awake,
+        .codec_options = options->codec_options,
     };
     if (!server_start(&server, options->serial, &params)) {
         return false;

app/src/scrcpy.h

@@ -16,6 +16,7 @@ struct scrcpy_options {
     const char *window_title;
     const char *push_target;
     const char *render_driver;
+    const char *codec_options;
     enum recorder_format record_format;
     struct port_range port_range;
     uint16_t max_size;
@@ -48,6 +49,7 @@ struct scrcpy_options {
     .window_title = NULL, \
     .push_target = NULL, \
     .render_driver = NULL, \
+    .codec_options = NULL, \
     .record_format = RECORDER_FORMAT_AUTO, \
     .port_range = { \
         .first = DEFAULT_LOCAL_PORT_RANGE_FIRST, \

app/src/server.c

@@ -270,6 +270,7 @@ execute_server(struct server *server, const struct server_params *params) {
         display_id_string,
         params->show_touches ? "true" : "false",
         params->stay_awake ? "true" : "false",
+        params->codec_options ? params->codec_options : "-",
     };
 #ifdef SERVER_DEBUGGER
     LOGI("Server debugger waiting for a client on device port "

app/src/server.h

@@ -44,6 +44,7 @@ struct server {
 
 struct server_params {
     const char *crop;
+    const char *codec_options;
     struct port_range port_range;
     uint16_t max_size;
     uint32_t bit_rate;

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

@@ -0,0 +1,112 @@
+package com.genymobile.scrcpy;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class CodecOption {
+    private String key;
+    private Object value;
+
+    public CodecOption(String key, Object value) {
+        this.key = key;
+        this.value = value;
+    }
+
+    public String getKey() {
+        return key;
+    }
+
+    public Object getValue() {
+        return value;
+    }
+
+    public static List<CodecOption> parse(String codecOptions) {
+        if ("-".equals(codecOptions)) {
+            return null;
+        }
+
+        List<CodecOption> result = new ArrayList<>();
+
+        boolean escape = false;
+        StringBuilder buf = new StringBuilder();
+
+        for (char c : codecOptions.toCharArray()) {
+            switch (c) {
+                case '\\':
+                    if (escape) {
+                        buf.append('\\');
+                        escape = false;
+                    } else {
+                        escape = true;
+                    }
+                    break;
+                case ',':
+                    if (escape) {
+                        buf.append(',');
+                        escape = false;
+                    } else {
+                        // This comma is a separator between codec options
+                        String codecOption = buf.toString();
+                        result.add(parseOption(codecOption));
+                        // Clear buf
+                        buf.setLength(0);
+                    }
+                    break;
+                default:
+                    buf.append(c);
+                    break;
+            }
+        }
+
+        if (buf.length() > 0) {
+            String codecOption = buf.toString();
+            result.add(parseOption(codecOption));
+        }
+
+        return result;
+    }
+
+    private static CodecOption parseOption(String option) {
+        int equalSignIndex = option.indexOf('=');
+        if (equalSignIndex == -1) {
+            throw new IllegalArgumentException("'=' expected");
+        }
+        String keyAndType = option.substring(0, equalSignIndex);
+        if (keyAndType.length() == 0) {
+            throw new IllegalArgumentException("Key may not be null");
+        }
+
+        String key;
+        String type;
+
+        int colonIndex = keyAndType.indexOf(':');
+        if (colonIndex != -1) {
+            key = keyAndType.substring(0, colonIndex);
+            type = keyAndType.substring(colonIndex + 1);
+        } else {
+            key = keyAndType;
+            type = "int"; // assume int by default
+        }
+
+        Object value;
+        String valueString = option.substring(equalSignIndex + 1);
+        switch (type) {
+            case "int":
+                value = Integer.parseInt(valueString);
+                break;
+            case "long":
+                value = Long.parseLong(valueString);
+                break;
+            case "float":
+                value = Float.parseFloat(valueString);
+                break;
+            case "string":
+                value = valueString;
+                break;
+            default:
+                throw new IllegalArgumentException("Invalid codec option type (int, long, float, str): " + type);
+        }
+
+        return new CodecOption(key, value);
+    }
+}

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

@@ -14,6 +14,7 @@ public class Options {
     private int displayId;
     private boolean showTouches;
     private boolean stayAwake;
+    private String codecOptions;
 
     public int getMaxSize() {
         return maxSize;
@@ -102,4 +103,12 @@ public class Options {
     public void setStayAwake(boolean stayAwake) {
         this.stayAwake = stayAwake;
     }
+
+    public String getCodecOptions() {
+        return codecOptions;
+    }
+
+    public void setCodecOptions(String codecOptions) {
+        this.codecOptions = codecOptions;
+    }
 }

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

@@ -12,6 +12,7 @@ import android.view.Surface;
 import java.io.FileDescriptor;
 import java.io.IOException;
 import java.nio.ByteBuffer;
+import java.util.List;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 public class ScreenEncoder implements Device.RotationListener {
@@ -25,15 +26,17 @@ public class ScreenEncoder implements Device.RotationListener {
     private final AtomicBoolean rotationChanged = new AtomicBoolean();
     private final ByteBuffer headerBuffer = ByteBuffer.allocate(12);
 
+    private List<CodecOption> codecOptions;
     private int bitRate;
     private int maxFps;
     private boolean sendFrameMeta;
     private long ptsOrigin;
 
-    public ScreenEncoder(boolean sendFrameMeta, int bitRate, int maxFps) {
+    public ScreenEncoder(boolean sendFrameMeta, int bitRate, int maxFps, List<CodecOption> codecOptions) {
         this.sendFrameMeta = sendFrameMeta;
         this.bitRate = bitRate;
         this.maxFps = maxFps;
+        this.codecOptions = codecOptions;
     }
 
     @Override
@@ -61,7 +64,7 @@ public class ScreenEncoder implements Device.RotationListener {
     }
 
     private void internalStreamScreen(Device device, FileDescriptor fd) throws IOException {
-        MediaFormat format = createFormat(bitRate, maxFps);
+        MediaFormat format = createFormat(bitRate, maxFps, codecOptions);
         device.setRotationListener(this);
         boolean alive;
         try {
@@ -151,7 +154,24 @@ public class ScreenEncoder implements Device.RotationListener {
         return MediaCodec.createEncoderByType(MediaFormat.MIMETYPE_VIDEO_AVC);
     }
 
-    private static MediaFormat createFormat(int bitRate, int maxFps) {
+    private static void setCodecOption(MediaFormat format, CodecOption codecOption) {
+        String key = codecOption.getKey();
+        Object value = codecOption.getValue();
+
+        if (value instanceof Integer) {
+            format.setInteger(key, (Integer) value);
+        } else if (value instanceof Long) {
+            format.setLong(key, (Long) value);
+        } else if (value instanceof Float) {
+            format.setFloat(key, (Float) value);
+        } else if (value instanceof String) {
+            format.setString(key, (String) value);
+        }
+
+        Ln.d("Codec option set: " + key + " (" + value.getClass().getSimpleName() + ") = " + value);
+    }
+
+    private static MediaFormat createFormat(int bitRate, int maxFps, List<CodecOption> codecOptions) {
         MediaFormat format = new MediaFormat();
         format.setString(MediaFormat.KEY_MIME, MediaFormat.MIMETYPE_VIDEO_AVC);
         format.setInteger(MediaFormat.KEY_BIT_RATE, bitRate);
@@ -167,6 +187,13 @@ public class ScreenEncoder implements Device.RotationListener {
             // <https://github.com/Genymobile/scrcpy/issues/488#issuecomment-567321437>
             format.setFloat(KEY_MAX_FPS_TO_ENCODER, maxFps);
         }
+
+        if (codecOptions != null) {
+            for (CodecOption option : codecOptions) {
+                setCodecOption(format, option);
+            }
+        }
+
         return format;
     }
 

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

@@ -8,6 +8,7 @@ import android.os.BatteryManager;
 import android.os.Build;
 
 import java.io.IOException;
+import java.util.List;
 
 public final class Server {
 
@@ -19,6 +20,7 @@ public final class Server {
     private static void scrcpy(Options options) throws IOException {
         Ln.i("Device: " + Build.MANUFACTURER + " " + Build.MODEL + " (Android " + Build.VERSION.RELEASE + ")");
         final Device device = new Device(options);
+        List<CodecOption> codecOptions = CodecOption.parse(options.getCodecOptions());
 
         boolean mustDisableShowTouchesOnCleanUp = false;
         int restoreStayOn = -1;
@@ -49,8 +51,9 @@ public final class Server {
         CleanUp.configure(mustDisableShowTouchesOnCleanUp, restoreStayOn);
 
         boolean tunnelForward = options.isTunnelForward();
+
         try (DesktopConnection connection = DesktopConnection.open(device, tunnelForward)) {
-            ScreenEncoder screenEncoder = new ScreenEncoder(options.getSendFrameMeta(), options.getBitRate(), options.getMaxFps());
+            ScreenEncoder screenEncoder = new ScreenEncoder(options.getSendFrameMeta(), options.getBitRate(), options.getMaxFps(), codecOptions);
 
             if (options.getControl()) {
                 final Controller controller = new Controller(device, connection);
@@ -116,7 +119,7 @@ public final class Server {
                     "The server version (" + BuildConfig.VERSION_NAME + ") does not match the client " + "(" + clientVersion + ")");
         }
 
-        final int expectedParameters = 12;
+        final int expectedParameters = 13;
         if (args.length != expectedParameters) {
             throw new IllegalArgumentException("Expecting " + expectedParameters + " parameters");
         }
@@ -157,6 +160,9 @@ public final class Server {
         boolean stayAwake = Boolean.parseBoolean(args[11]);
         options.setStayAwake(stayAwake);
 
+        String codecOptions = args[12];
+        options.setCodecOptions(codecOptions);
+
         return options;
     }
 

server/src/test/java/com/genymobile/scrcpy/CodecOptionsTest.java

@@ -0,0 +1,114 @@
+package com.genymobile.scrcpy;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.List;
+
+public class CodecOptionsTest {
+
+    @Test
+    public void testIntegerImplicit() {
+        List<CodecOption> codecOptions = CodecOption.parse("some_key=5");
+
+        Assert.assertEquals(1, codecOptions.size());
+
+        CodecOption option = codecOptions.get(0);
+        Assert.assertEquals("some_key", option.getKey());
+        Assert.assertEquals(5, option.getValue());
+    }
+
+    @Test
+    public void testInteger() {
+        List<CodecOption> codecOptions = CodecOption.parse("some_key:int=5");
+
+        Assert.assertEquals(1, codecOptions.size());
+
+        CodecOption option = codecOptions.get(0);
+        Assert.assertEquals("some_key", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof Integer);
+        Assert.assertEquals(5, option.getValue());
+    }
+
+    @Test
+    public void testLong() {
+        List<CodecOption> codecOptions = CodecOption.parse("some_key:long=5");
+
+        Assert.assertEquals(1, codecOptions.size());
+
+        CodecOption option = codecOptions.get(0);
+        Assert.assertEquals("some_key", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof Long);
+        Assert.assertEquals(5L, option.getValue());
+    }
+
+    @Test
+    public void testFloat() {
+        List<CodecOption> codecOptions = CodecOption.parse("some_key:float=4.5");
+
+        Assert.assertEquals(1, codecOptions.size());
+
+        CodecOption option = codecOptions.get(0);
+        Assert.assertEquals("some_key", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof Float);
+        Assert.assertEquals(4.5f, option.getValue());
+    }
+
+    @Test
+    public void testString() {
+        List<CodecOption> codecOptions = CodecOption.parse("some_key:string=some_value");
+
+        Assert.assertEquals(1, codecOptions.size());
+
+        CodecOption option = codecOptions.get(0);
+        Assert.assertEquals("some_key", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof String);
+        Assert.assertEquals("some_value", option.getValue());
+    }
+
+    @Test
+    public void testStringEscaped() {
+        List<CodecOption> codecOptions = CodecOption.parse("some_key:string=warning\\,this_is_not=a_new_key");
+
+        Assert.assertEquals(1, codecOptions.size());
+
+        CodecOption option = codecOptions.get(0);
+        Assert.assertEquals("some_key", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof String);
+        Assert.assertEquals("warning,this_is_not=a_new_key", option.getValue());
+    }
+
+    @Test
+    public void testList() {
+        List<CodecOption> codecOptions = CodecOption.parse("a=1,b:int=2,c:long=3,d:float=4.5,e:string=a\\,b=c");
+
+        Assert.assertEquals(5, codecOptions.size());
+
+        CodecOption option;
+
+        option = codecOptions.get(0);
+        Assert.assertEquals("a", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof Integer);
+        Assert.assertEquals(1, option.getValue());
+
+        option = codecOptions.get(1);
+        Assert.assertEquals("b", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof Integer);
+        Assert.assertEquals(2, option.getValue());
+
+        option = codecOptions.get(2);
+        Assert.assertEquals("c", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof Long);
+        Assert.assertEquals(3L, option.getValue());
+
+        option = codecOptions.get(3);
+        Assert.assertEquals("d", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof Float);
+        Assert.assertEquals(4.5f, option.getValue());
+
+        option = codecOptions.get(4);
+        Assert.assertEquals("e", option.getKey());
+        Assert.assertTrue(option.getValue() instanceof String);
+        Assert.assertEquals("a,b=c", option.getValue());
+    }
+}