我正在编写一个记录屏幕和音频的应用程序。虽然屏幕录制效果很好,但我很难使用JDK库获取原始音频。这是代码:
try {
// Now, we're going to loop
long startTime = System.nanoTime();
System.out.println("Encoding Image.....");
while (!Thread.currentThread().isInterrupted()) {
// take the screen shot
BufferedImage screen = robot.createScreenCapture(screenBounds);
// convert to the right image type
BufferedImage bgrScreen = convertToType(screen,
BufferedImage.TYPE_3BYTE_BGR);
// encode the image
writer.encodeVideo(0, bgrScreen, System.nanoTime()
- startTime, TimeUnit.NANOSECONDS);
/* Need to get audio here and then encode using xuggler. Something like
WaveData wd = new WaveData();
TargetDataLine line;
AudioInputStream aus = new AudioInputStream(line);
short[] samples = getSourceSamples();
writer.encodeAudio(0, samples); */
if (timeCreation < 10) {
timeCreation = getGMTTime();
}
// sleep for framerate milliseconds
try {
Thread.sleep((long) (1000 / FRAME_RATE.getDouble()));
} catch (Exception ex) {
System.err.println("stopping....");
break;
}
}
// Finally we tell the writer to close and write the trailer if
// needed
} finally {
writer.close();
}
此page有一些伪代码,如
while(haveMoreAudio())
{
short[] samples = getSourceSamples();
writer.encodeAudio(0, samples);
}
但我应该为getSourceSamples()
做些什么?
另外,一个额外的问题 - 在这种方法中可以从多个麦克风中进行选择吗?
答案 0 :(得分:2)
试试这个:
// Pick a format. Need 16 bits, the rest can be set to anything
// It is better to enumerate the formats that the system supports, because getLine() can error out with any particular format
AudioFormat audioFormat = new AudioFormat(44100.0F, 16, 2, true, false);
// Get default TargetDataLine with that format
DataLine.Info dataLineInfo = new DataLine.Info( TargetDataLine.class, audioFormat );
TargetDataLine line = (TargetDataLine) AudioSystem.getLine(dataLineInfo);
// Open and start capturing audio
line.open(audioFormat, line.getBufferSize());
line.start();
while (true) {
// read as raw bytes
byte[] audioBytes = new byte[ line.getBufferSize() / 2 ]; // best size?
int numBytesRead = 0;
numBytesRead = line.read(audioBytes, 0, audioBytes.length);
// convert to signed shorts representing samples
int numSamplesRead = numBytesRead / 2;
short[] audioSamples = new short[ numSamplesRead ];
if (format.isBigEndian()) {
for (int i = 0; i < numSamplesRead; i++) {
audioSamples[i] = (short)((audioBytes[2*i] << 8) | audioBytes[2*i + 1]);
}
}
else {
for (int i = 0; i < numSamplesRead; i++) {
audioSamples[i] = (short)((audioBytes[2*i + 1] << 8) | audioBytes[2*i]);
}
}
// use audioSamples in Xuggler etc
}
要选择麦克风,您可能必须这样做:
Mixer.Info[] mixerInfo = AudioSystem.getMixerInfo();
// Look through and select a mixer here, different mixers should be different inputs
int selectedMixerIndex = 0;
Mixer mixer = AudioSystem.getMixer(mixerInfo[ selectedMixerIndex ]);
TargetDataLine line = (TargetDataLine) mixer.getLine(dataLineInfo);
我认为多个麦克风可能会在一个调音台中显示为不同的源数据线。在这种情况下,您必须打开它们并致电dataLine.getControl(FloatControl.Type.MASTER_GAIN).setValue( volume );
以打开和关闭它们。
请参阅: WaveData.java