JMF 麦克风音量控制器

Question

JMF中如何获取麦克风音量控制器？

这就是我所拥有的：

我尝试了你的这个实现概念，但是当我尝试获取流时，我一直从第一个卷处理器得到一个空值，我是这样做的：

// the device is the media device specifically audio
Processor processorForVolume = Manager.createProcessor(device.getLocator());

// wait until configured
ProcessorStates newState = new ProcessorStateListener(Processor.Configured).waitForProcessorState(processorForVolume);
System.out.println("volumeProcessorState: "+newState);

// setting the content descriptor to null - read in another thread this allows to get the gain control
processorForVolume.setContentDescriptor(null);

// set the track control format to one supported by the device and the track control.
// I didn't match it to an RTP allowed format, but I don't think this has anything to do with it...
TrackControl[] trackControls = processorForVolume.getTrackControls();
if (trackControls.length == 0)
    throw new MC_Exception("No track controls where found for this device:", new Object[]{device});
for (TrackControl control : trackControls)
    trackManipulator.manipulateTrackControls(control);

// wait until the processor is realized
newState = new ProcessorStateListener(Controller.Realized).waitForProcessorState(processorForVolume);
System.out.println("volumeProcessorState: "+newState);

// receives the gain control
micVolumeController = processorForVolume.getGainControl();

// cannot get the output stream to process further... any suggestions?
processor = Manager.createProcessor(processorForVolume.getDataOutput());
new ProcessorStateListener(Processor.Configured).waitForProcessorState(processor);
processor.setContentDescriptor(DeviceCapturingManager.RAW_RTP);
new ProcessorStateListener(Controller.Realized).waitForProcessorState(processor);

这是它生成的输出：

volumeProcessorState：已配置 格式设置为跟踪控制 - com.sun.media.ProcessEngine$ProcTControl@1627c16: 线性，48000.0 Hz，16 位，立体声， LittleEndian，签名 volumeProcessorState：已实现

处理器输出的数据为Null。

我应该明确一点，当内容描述符 != null 时，我确实得到了一个输出流，但没有音量控制器，当它为 null 时，我得到了控制器，但没有流。

我尝试连接到音频麦克风设备

亚当。

Answer 1

麦克风没有音量组件！必须自己实现。