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在过去的两天里,我一直在寻找一种通过我的 Raspiberry pi 无头扬声器控制 iPhone 媒体播放的方法。

我已经使用以下教程成功设置了 pi: Raspbian Stretch 上的 Headless A2DP 音频流 ,现在我正在寻找一种方法来控制我的树莓派中音频流的播放。

我一直在研究 MediaTransport1、MediaPlayer1、MediaControl1,但不幸的是我没有成功。

给你几个我已经执行的试验和错误的例子:

为了:

dbus-send --system --print-reply --dest=org.bluez /org/bluez/hci0/dev_C8_85_50_B1_C8_6B org.bluez.MediaPlayer1.Pause

我收到了:

Error org.freedesktop.DBus.Error.UnknownMethod: Method "Pause" with signature "" on interface "org.bluez.MediaPlayer1" doesn't exist

为了

qdbus --system org.bluez /org/bluez/hci0/dev_C8_85_50_B1_C8_6B/fd0 org.freedesktop.DBus.Properties.Set org.bluez.MediaTransport1 Volume 127

我收到了

Error: org.freedesktop.DBus.Error.InvalidSignature
Invalid signature for 'Volume'

此外,我发现了一个播放器,我认为我可以用它来构建我自己的脚本作为示例 ,但遇到了一个错误:

pi@raspberrypi:~/blueutils $ python simpleplayer.py


Available commands:
        PropertiesChanged(interface, properties)
        help(cmd)

Use python syntax to pass arguments to available methods.
E.g.: PropertiesChanged({'Metadata' : {'Title': 'My title',             'Album': 'my album' }})

>>> <Interface <ProxyObject wrapping <dbus._dbus.SystemBus (system) at 0xb61968d0> :1.13 /org/bluez/hci0 at 0xb619db70> implementing 'org.bluez.Media1' at 0xb619dc50>
Traceback (most recent call last):
  File "simpleplayer.py", line 197, in <module>
    media.RegisterPlayer(dbus.ObjectPath(path), player.properties)
  File "/usr/lib/python2.7/dist-packages/dbus/proxies.py", line 70, in __call__
    return self._proxy_method(*args, **keywords)
  File "/usr/lib/python2.7/dist-packages/dbus/proxies.py", line 145, in __call__
    **keywords)
  File "/usr/lib/python2.7/dist-packages/dbus/connection.py", line 651, in call_blocking
    message, timeout)
dbus.exceptions.DBusException: org.bluez.Error.NotSupported: Operation is not supported

当我反省时

dbus-send --system --print-reply --dest=org.bluez /org/bluez/hci0 org.freedesktop.DBus.Introspectable.Introspect

我明白他的:

<node>
    <interface name="org.freedesktop.DBus.Introspectable">
        <method name="Introspect">
            <arg name="xml" type="s" direction="out"/>
        </method>
    </interface>
    <interface name="org.bluez.Adapter1">
        <method name="StartDiscovery"></method>
        <method name="SetDiscoveryFilter">
            <arg name="properties" type="a{sv}" direction="in"/>
        </method>
        <method name="StopDiscovery"></method>
        <method name="RemoveDevice">
            <arg name="device" type="o" direction="in"/>
        </method>
        <property name="Address" type="s" access="read"></property>
        <property name="Name" type="s" access="read"></property>
        <property name="Alias" type="s" access="readwrite"></property>
        <property name="Class" type="u" access="read"></property>
        <property name="Powered" type="b" access="readwrite"></property>
        <property name="Discoverable" type="b" access="readwrite"></property>
        <property name="DiscoverableTimeout" type="u" access="readwrite"></property>]

        <property name="Pairable" type="b" access="readwrite"></property>
        <property name="PairableTimeout" type="u" access="readwrite"></property>
        <property name="Discovering" type="b" access="read"></property>
        <property name="UUIDs" type="as" access="read"></property>
        <property name="Modalias" type="s" access="read"></property>
    </interface>
    <interface name="org.freedesktop.DBus.Properties">
        <method name="Get">
            <arg name="interface" type="s" direction="in"/>
            <arg name="name" type="s" direction="in"/>
            <arg name="value" type="v" direction="out"/>
        </method>
        <method name="Set">
            <arg name="interface" type="s" direction="in"/>
            <arg name="name" type="s" direction="in"/>
            <arg name="value" type="v" direction="in"/>
        </method>
        <method name="GetAll">
            <arg name="interface" type="s" direction="in"/>
            <arg name="properties" type="a{sv}" direction="out"/>
        </method>
        <signal name="PropertiesChanged">
            <arg name="interface" type="s"/>
            <arg name="changed_properties" type="a{sv}"/>
            <arg name="invalidated_properties" type="as"/>
        </signal>
    </interface>
    <interface name="org.bluez.GattManager1">
        <method name="RegisterApplication">
            <arg name="application" type="o" direction="in"/>
            <arg name="options" type="a{sv}" direction="in"/>
        </method>
        <method name="UnregisterApplication">
            <arg name="application" type="o" direction="in"/>
        </method>
    </interface>
    <interface name="org.bluez.Media1">
        <method name="RegisterEndpoint">
            <arg name="endpoint" type="o" direction="in"/>
            <arg name="properties" type="a{sv}" direction="in"/>
        </method>
        <method name="UnregisterEndpoint">
            <arg name="endpoint" type="o" direction="in"/>
        </method>
        <method name="RegisterPlayer">
            <arg name="player" type="o" direction="in"/>
            <arg name="properties" type="a{sv}" direction="in"/>
        </method>
        <method name="UnregisterPlayer">
            <arg name="player" type="o" direction="in"/>
        </method>
    </interface>
    <node name="dev_40_9C_28_07_63_DD"/>
    <node name="dev_C8_85_50_B1_C8_6B"/>
</node>

谁能帮我解决这个问题,或者有人知道使用树莓派控制手机上音乐播放的程序吗?

问候。

更新 1:非常感谢@Parthiban,因为它运行良好。

此外,我不得不说我按照此处的教程将 bluez 版本重新安装到 5.50:在 Raspberry Pi 上安装 bluez,因为我看不到 /playerX(在我的情况下为 0)。在我编译源代码之前,我做了一些额外的工作(不确定它是否相关,但它没有伤害),我添加了.auto_connect = true

所示的 avrcp 配置文件:

这里

希望这可以帮助每个可能面临我的问题的人

4

1 回答 1

2

您需要指定签名来设置音量,如下所示,

dbus-send --system --print-reply --type=method_call --dest='org.bluez' '/org/bluez/hci0/dev_C8_85_50_B1_C8_6B/fd0' org.freedesktop.DBus.Properties.Set string:"org.bluez.MediaTransport1" string:"Volume" variant:uint16:127

这是因为,正如dbus 规范中提到的,在使用 set 时需要指定三个参数,

  1. 接口名称
  2. 属性名称
  3. 属性值作为变体

对于暂停方法,请使用“ ”探索org.bluez.MediaPlayer1设备的“ ”界面org.freedesktop.DBus.Introspectable.Introspect。您用来访问“暂停”方法的对象路径是错误的。如此处所述,您需要使用“ [variable prefix]/{hci0,hci1,...}/dev_XX_XX_XX_XX_XX_XX/playerX”。

所以在你的情况下,它应该是,

dbus-send --system --print-reply --type=method_call --dest='org.bluez' '/org/bluez/hci0/dev_C8_85_50_B1_C8_6B/playerX' org.bluez.MediaPlayer1.Pause

playerX 需要被您的设备播放器替换的地方(您可以从 Introspect 获得它或观看“InterfaceAdded”信号。

于 2018-09-07T08:52:51.693 回答