Question

在OS X中，如何判断相机或麦克风是否正被其他应用程序或进程使用？除非其他应用程序锁定了设备，否则以下情况似乎无效。

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://xmlns.jcp.org/xml/ns/javaee"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
    id="WebApp_ID" version="3.1">

    <display-name>NpCWS</display-name>

    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>

    <servlet>
        <description>Apache CXF Endpoint</description>
        <display-name>cxf</display-name>
        <servlet-name>cxf</servlet-name>
        <servlet-class>org.apache.cxf.transport.servlet.CXFServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>cxf</servlet-name>
        <url-pattern>/services/*</url-pattern>
    </servlet-mapping>

    <session-config>
        <session-timeout>60</session-timeout>
    </session-config>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>WEB-INF/cxf-beans.xml</param-value>
    </context-param>

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
</web-app>

Answer 1

您可以使用CoreAudio检查麦克风是否正在使用中。

AudioObjectPropertyAddress propertyAddress = { kAudioHardwarePropertyDevices, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster };

UInt32 dataSize = 0;
OSStatus status = AudioObjectGetPropertyDataSize(kAudioObjectSystemObject, &propertyAddress, 0, NULL, &dataSize);
if(kAudioHardwareNoError != status) {
    fprintf(stderr, "AudioObjectGetPropertyDataSize (kAudioHardwarePropertyDevices) failed: %i\n", status);
    //return NULL;
    return;
}

UInt32 deviceCount = (UInt32)(dataSize / sizeof(AudioDeviceID));

AudioDeviceID *audioDevices = (AudioDeviceID*)(malloc(dataSize));
if(NULL == audioDevices) {
    fputs("Unable to allocate memory", stderr);
    return;
}

status = AudioObjectGetPropertyData(kAudioObjectSystemObject, &propertyAddress, 0, NULL, &dataSize, audioDevices);
if(kAudioHardwareNoError != status) {
    fprintf(stderr, "AudioObjectGetPropertyData (kAudioHardwarePropertyDevices) failed: %i\n", status);
    free(audioDevices), audioDevices = NULL;
    return ;
}

CFMutableArrayRef inputDeviceArray = CFArrayCreateMutable(kCFAllocatorDefault, deviceCount, &kCFTypeArrayCallBacks);
if(NULL == inputDeviceArray) {
    fputs("CFArrayCreateMutable failed", stderr);
    free(audioDevices), audioDevices = NULL;
    return ;
}`

现在迭代所有设备并获取属性数据kAudioDevicePropertyDeviceIsRunningSomewhere

CFBooleanRef deviceIsRunning = NULL; dataSize = sizeof(deviceIsRunning); propertyAddress.mSelector = kAudioDevicePropertyDeviceIsRunningSomewhere; status = AudioObjectGetPropertyData(audioDevices[i], &propertyAddress, 0, NULL, &dataSize, &deviceIsRunning);

检查deviceIsRunning变量。

我对视频设备一无所知。但如果我找到一些解决方案，我会更新我的答案。

希望得到这个帮助。

如何判断相机是否正在被其他进程使用？

1 个答案: