在Android中,是否可以从摄像头录制视频时不包含音频流?
目标:减小输出文件大小。
在Android中,是否可以从摄像头录制视频时不包含音频流?
目标:减小输出文件大小。
你可以通过从内置配置文件(CamcorderProfile
)中复制所需字段来准备 MediaRecorder
。只需略过音频设置,你就可以开始了。编辑下面的代码以满足你的需求,这里的步骤3是必要的部分。
private boolean prepareVideoRecorder() {
mCamera = getCameraInstance();
mMediaRecorder = new MediaRecorder();
// store the quality profile required
CamcorderProfile profile = CamcorderProfile.get(cameraid, CamcorderProfile.QUALITY_HIGH);
// Step 1: Unlock and set camera to MediaRecorder
mCamera.unlock();
mMediaRecorder.setCamera(mCamera);
// Step 2: Set sources
mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
// Step 3: Set all values contained in profile except audio settings
mMediaRecorder.setOutputFormat(profile.fileFormat);
mMediaRecorder.setVideoEncoder(profile.videoCodec);
mMediaRecorder.setVideoEncodingBitRate(profile.videoBitRate);
mMediaRecorder.setVideoFrameRate(profile.videoFrameRate);
mMediaRecorder.setVideoSize(profile.videoFrameWidth, profile.videoFrameHeight);
// Step 4: Set output file
mMediaRecorder.setOutputFile(getOutputMediaFile(MEDIA_TYPE_VIDEO).toString());
// Step 5: Set the preview output
mMediaRecorder.setPreviewDisplay(mPreview.getHolder().getSurface());
// Step 6: Prepare configured MediaRecorder
try {
mMediaRecorder.prepare();
} catch (IllegalStateException e) {
releaseMediaRecorder();
return false;
} catch (IOException e) {
releaseMediaRecorder();
return false;
}
return true;
}
您可以在不调用setAudio*的情况下使用MediaRecorder。这是我第一次使用MediaRecorder,但这个例子似乎可以工作:
public class CamcorderView extends SurfaceView implements
SurfaceHolder.Callback {
private SurfaceHolder mHolder;
private Camera mCamera;
private MediaRecorder mRecorder;
public CamcorderView(Context context, AttributeSet attrs) {
super(context, attrs);
mHolder = getHolder();
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
mHolder.addCallback(this);
mCamera = Camera.open();
mRecorder = new MediaRecorder();
}
public void stop() {
mRecorder.stop();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
mCamera.unlock();
mRecorder.setCamera(mCamera);
mRecorder.setPreviewDisplay(mHolder.getSurface());
// You may want to change these
mRecorder.setVideoSource(MediaRecorder.VideoSource.DEFAULT);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT);
mRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.DEFAULT);
// You'll definitely want to change this
mRecorder.setOutputFile("/mnt/sdcard/out");
try {
mRecorder.prepare();
} catch (IllegalStateException e) {
Log.e("IllegalStateException", e.toString());
} catch (IOException e) {
Log.e("IOException", e.toString());
}
mRecorder.start();
}
}
您可能还需要调用以下方法:
setVideoSize(int, int);
:设置视频尺寸setVideoFrameRate(int);
:设置视频帧率
camcorderProfile = CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH);
,然后所有设置都将应用为mediaRecorder.setProfile(camcorderProfile);
。 - SergiiAudioSource
在Android 10+上并不起作用;MediaRecorder.prepare()
会失败。我一直在寻找适用于此API级别的方法,但没有成功。 - head in the codes