我在SO和一些不错的博客文章上进行了很多研究，但是似乎我对读取视频和音频缓冲区有独特的要求，以便在录制过程中进一步对其进行处理。
我的用例就像当用户开始录制视频时，我需要使用ML-Face-Detection-Kit连续处理视频帧，还需要连续处理音频帧以确保用户说出了什么并检测到噪声水平也一样为此，我认为视频和音频都需要放在单独的缓冲区中，经过处理后，我将其合并并保存为MP4文件作为录音。
我尝试过由好人CameraView开发的Mattia Iavarone，但它仅提供视频帧。
我愿意接受其他有用的建议/反馈来处理这种情况。
答案 0 :(得分：-1)
这里是一个引用JavaCV库的answer示例的RecordActivity.java。
它使用单独的音频和视频线程来实时获取帧。
编辑1：按照建议，我已包括Bytedeco的RecordActivity.java的代码示例。
package org.bytedeco.javacv.recordactivity;
import android.app.Activity;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.hardware.Camera;
import android.hardware.Camera.PreviewCallback;
import android.media.AudioFormat;
import android.media.AudioRecord;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.PowerManager;
import android.util.Log;
import android.view.Display;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ShortBuffer;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import org.bytedeco.javacpp.avutil;
import org.bytedeco.javacv.FFmpegFrameFilter;
import org.bytedeco.javacv.FFmpegFrameRecorder;
import org.bytedeco.javacv.Frame;
import org.bytedeco.javacv.FrameFilter;
public class RecordActivity extends Activity implements OnClickListener {
private final static String CLASS_LABEL = "RecordActivity";
private final static String LOG_TAG = CLASS_LABEL;
private String ffmpeg_link = "/mnt/sdcard/stream.flv";
long startTime = 0;
boolean recording = false;
private FFmpegFrameRecorder recorder;
private boolean isPreviewOn = false;
/*Filter information, change boolean to true if adding a fitler*/
private boolean addFilter = true;
private String filterString = "";
FFmpegFrameFilter filter;
private int sampleAudioRateInHz = 44100;
private int imageWidth = 320;
private int imageHeight = 240;
private int frameRate = 30;
/* audio data getting thread */
private AudioRecord audioRecord;
private AudioRecordRunnable audioRecordRunnable;
private Thread audioThread;
volatile boolean runAudioThread = true;
/* video data getting thread */
private Camera cameraDevice;
private CameraView cameraView;
private Frame yuvImage = null;
/* layout setting */
private final int bg_screen_bx = 232;
private final int bg_screen_by = 128;
private final int bg_screen_width = 700;
private final int bg_screen_height = 500;
private final int bg_width = 1123;
private final int bg_height = 715;
private final int live_width = 640;
private final int live_height = 480;
private int screenWidth, screenHeight;
private Button btnRecorderControl;
/* The number of seconds in the continuous record loop (or 0 to disable loop). */
final int RECORD_LENGTH = 0;
Frame[] images;
long[] timestamps;
ShortBuffer[] samples;
int imagesIndex, samplesIndex;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
setContentView(R.layout.main);
initLayout();
}
@Override
protected void onDestroy() {
super.onDestroy();
recording = false;
if (cameraView != null) {
cameraView.stopPreview();
}
if(cameraDevice != null) {
cameraDevice.stopPreview();
cameraDevice.release();
cameraDevice = null;
}
}
private void initLayout() {
/* get size of screen */
Display display = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
screenWidth = display.getWidth();
screenHeight = display.getHeight();
RelativeLayout.LayoutParams layoutParam = null;
LayoutInflater myInflate = null;
myInflate = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
RelativeLayout topLayout = new RelativeLayout(this);
setContentView(topLayout);
LinearLayout preViewLayout = (LinearLayout) myInflate.inflate(R.layout.main, null);
layoutParam = new RelativeLayout.LayoutParams(screenWidth, screenHeight);
topLayout.addView(preViewLayout, layoutParam);
/* add control button: start and stop */
btnRecorderControl = (Button) findViewById(R.id.recorder_control);
btnRecorderControl.setText("Start");
btnRecorderControl.setOnClickListener(this);
/* add camera view */
int display_width_d = (int) (1.0 * bg_screen_width * screenWidth / bg_width);
int display_height_d = (int) (1.0 * bg_screen_height * screenHeight / bg_height);
int prev_rw, prev_rh;
if (1.0 * display_width_d / display_height_d > 1.0 * live_width / live_height) {
prev_rh = display_height_d;
prev_rw = (int) (1.0 * display_height_d * live_width / live_height);
} else {
prev_rw = display_width_d;
prev_rh = (int) (1.0 * display_width_d * live_height / live_width);
}
layoutParam = new RelativeLayout.LayoutParams(prev_rw, prev_rh);
layoutParam.topMargin = (int) (1.0 * bg_screen_by * screenHeight / bg_height);
layoutParam.leftMargin = (int) (1.0 * bg_screen_bx * screenWidth / bg_width);
cameraDevice = Camera.open();
Log.i(LOG_TAG, "cameara open");
cameraView = new CameraView(this, cameraDevice);
topLayout.addView(cameraView, layoutParam);
Log.i(LOG_TAG, "cameara preview start: OK");
}
//---------------------------------------
// initialize ffmpeg_recorder
//---------------------------------------
private void initRecorder() {
Log.w(LOG_TAG,"init recorder");
if (RECORD_LENGTH > 0) {
imagesIndex = 0;
images = new Frame[RECORD_LENGTH * frameRate];
timestamps = new long[images.length];
for (int i = 0; i < images.length; i++) {
images[i] = new Frame(imageWidth, imageHeight, Frame.DEPTH_UBYTE, 2);
timestamps[i] = -1;
}
} else if (yuvImage == null) {
yuvImage = new Frame(imageWidth, imageHeight, Frame.DEPTH_UBYTE, 2);
Log.i(LOG_TAG, "create yuvImage");
}
Log.i(LOG_TAG, "ffmpeg_url: " + ffmpeg_link);
recorder = new FFmpegFrameRecorder(ffmpeg_link, imageWidth, imageHeight, 1);
recorder.setFormat("flv");
recorder.setSampleRate(sampleAudioRateInHz);
// Set in the surface changed method
recorder.setFrameRate(frameRate);
// The filterString is any ffmpeg filter.
// Here is the link for a list: https://ffmpeg.org/ffmpeg-filters.html
filterString = "transpose=0";
filter = new FFmpegFrameFilter(filterString, imageWidth, imageHeight);
//default format on android
filter.setPixelFormat(avutil.AV_PIX_FMT_NV21);
Log.i(LOG_TAG, "recorder initialize success");
audioRecordRunnable = new AudioRecordRunnable();
audioThread = new Thread(audioRecordRunnable);
runAudioThread = true;
}
public void startRecording() {
initRecorder();
try {
recorder.start();
startTime = System.currentTimeMillis();
recording = true;
audioThread.start();
if(addFilter) {
filter.start();
}
} catch (FFmpegFrameRecorder.Exception | FrameFilter.Exception e) {
e.printStackTrace();
}
}
public void stopRecording() {
runAudioThread = false;
try {
audioThread.join();
} catch (InterruptedException e) {
// reset interrupt to be nice
Thread.currentThread().interrupt();
return;
}
audioRecordRunnable = null;
audioThread = null;
if (recorder != null && recording) {
if (RECORD_LENGTH > 0) {
Log.v(LOG_TAG,"Writing frames");
try {
int firstIndex = imagesIndex % samples.length;
int lastIndex = (imagesIndex - 1) % images.length;
if (imagesIndex <= images.length) {
firstIndex = 0;
lastIndex = imagesIndex - 1;
}
if ((startTime = timestamps[lastIndex] - RECORD_LENGTH * 1000000L) < 0) {
startTime = 0;
}
if (lastIndex < firstIndex) {
lastIndex += images.length;
}
for (int i = firstIndex; i <= lastIndex; i++) {
long t = timestamps[i % timestamps.length] - startTime;
if (t >= 0) {
if (t > recorder.getTimestamp()) {
recorder.setTimestamp(t);
}
recorder.record(images[i % images.length]);
}
}
firstIndex = samplesIndex % samples.length;
lastIndex = (samplesIndex - 1) % samples.length;
if (samplesIndex <= samples.length) {
firstIndex = 0;
lastIndex = samplesIndex - 1;
}
if (lastIndex < firstIndex) {
lastIndex += samples.length;
}
for (int i = firstIndex; i <= lastIndex; i++) {
recorder.recordSamples(samples[i % samples.length]);
}
} catch (FFmpegFrameRecorder.Exception e) {
Log.v(LOG_TAG,e.getMessage());
e.printStackTrace();
}
}
recording = false;
Log.v(LOG_TAG,"Finishing recording, calling stop and release on recorder");
try {
recorder.stop();
recorder.release();
filter.stop();
filter.release();
} catch (FFmpegFrameRecorder.Exception | FrameFilter.Exception e) {
e.printStackTrace();
}
recorder = null;
}
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
if (recording) {
stopRecording();
}
finish();
return true;
}
return super.onKeyDown(keyCode, event);
}
//---------------------------------------------
// audio thread, gets and encodes audio data
//---------------------------------------------
class AudioRecordRunnable implements Runnable {
@Override
public void run() {
android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_URGENT_AUDIO);
// Audio
int bufferSize;
ShortBuffer audioData;
int bufferReadResult;
bufferSize = AudioRecord.getMinBufferSize(sampleAudioRateInHz,
AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT);
audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, sampleAudioRateInHz,
AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT, bufferSize);
if (RECORD_LENGTH > 0) {
samplesIndex = 0;
samples = new ShortBuffer[RECORD_LENGTH * sampleAudioRateInHz * 2 / bufferSize + 1];
for (int i = 0; i < samples.length; i++) {
samples[i] = ShortBuffer.allocate(bufferSize);
}
} else {
audioData = ShortBuffer.allocate(bufferSize);
}
Log.d(LOG_TAG, "audioRecord.startRecording()");
audioRecord.startRecording();
/* ffmpeg_audio encoding loop */
while (runAudioThread) {
if (RECORD_LENGTH > 0) {
audioData = samples[samplesIndex++ % samples.length];
audioData.position(0).limit(0);
}
//Log.v(LOG_TAG,"recording? " + recording);
bufferReadResult = audioRecord.read(audioData.array(), 0, audioData.capacity());
audioData.limit(bufferReadResult);
if (bufferReadResult > 0) {
Log.v(LOG_TAG,"bufferReadResult: " + bufferReadResult);
// If "recording" isn't true when start this thread, it never get's set according to this if statement...!!!
// Why? Good question...
if (recording) {
if (RECORD_LENGTH <= 0) try {
recorder.recordSamples(audioData);
//Log.v(LOG_TAG,"recording " + 1024*i + " to " + 1024*i+1024);
} catch (FFmpegFrameRecorder.Exception e) {
Log.v(LOG_TAG,e.getMessage());
e.printStackTrace();
}
}
}
}
Log.v(LOG_TAG,"AudioThread Finished, release audioRecord");
/* encoding finish, release recorder */
if (audioRecord != null) {
audioRecord.stop();
audioRecord.release();
audioRecord = null;
Log.v(LOG_TAG,"audioRecord released");
}
}
}
//---------------------------------------------
// camera thread, gets and encodes video data
//---------------------------------------------
class CameraView extends SurfaceView implements SurfaceHolder.Callback, PreviewCallback {
private SurfaceHolder mHolder;
private Camera mCamera;
public CameraView(Context context, Camera camera) {
super(context);
Log.w("camera","camera view");
mCamera = camera;
mHolder = getHolder();
mHolder.addCallback(CameraView.this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
mCamera.setPreviewCallback(CameraView.this);
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
stopPreview();
mCamera.setPreviewDisplay(holder);
} catch (IOException exception) {
mCamera.release();
mCamera = null;
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
stopPreview();
Camera.Parameters camParams = mCamera.getParameters();
List<Camera.Size> sizes = camParams.getSupportedPreviewSizes();
// Sort the list in ascending order
Collections.sort(sizes, new Comparator<Camera.Size>() {
public int compare(final Camera.Size a, final Camera.Size b) {
return a.width * a.height - b.width * b.height;
}
});
// Pick the first preview size that is equal or bigger, or pick the last (biggest) option if we cannot
// reach the initial settings of imageWidth/imageHeight.
for (int i = 0; i < sizes.size(); i++) {
if ((sizes.get(i).width >= imageWidth && sizes.get(i).height >= imageHeight) || i == sizes.size() - 1) {
imageWidth = sizes.get(i).width;
imageHeight = sizes.get(i).height;
Log.v(LOG_TAG, "Changed to supported resolution: " + imageWidth + "x" + imageHeight);
break;
}
}
camParams.setPreviewSize(imageWidth, imageHeight);
Log.v(LOG_TAG,"Setting imageWidth: " + imageWidth + " imageHeight: " + imageHeight + " frameRate: " + frameRate);
camParams.setPreviewFrameRate(frameRate);
Log.v(LOG_TAG,"Preview Framerate: " + camParams.getPreviewFrameRate());
mCamera.setParameters(camParams);
// Set the holder (which might have changed) again
try {
mCamera.setPreviewDisplay(holder);
mCamera.setPreviewCallback(CameraView.this);
startPreview();
} catch (Exception e) {
Log.e(LOG_TAG, "Could not set preview display in surfaceChanged");
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
try {
mHolder.addCallback(null);
mCamera.setPreviewCallback(null);
} catch (RuntimeException e) {
// The camera has probably just been released, ignore.
}
}
public void startPreview() {
if (!isPreviewOn && mCamera != null) {
isPreviewOn = true;
mCamera.startPreview();
}
}
public void stopPreview() {
if (isPreviewOn && mCamera != null) {
isPreviewOn = false;
mCamera.stopPreview();
}
}
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
if (audioRecord == null || audioRecord.getRecordingState() != AudioRecord.RECORDSTATE_RECORDING) {
startTime = System.currentTimeMillis();
return;
}
if (RECORD_LENGTH > 0) {
int i = imagesIndex++ % images.length;
yuvImage = images[i];
timestamps[i] = 1000 * (System.currentTimeMillis() - startTime);
}
/* get video data */
if (yuvImage != null && recording) {
((ByteBuffer)yuvImage.image[0].position(0)).put(data);
if (RECORD_LENGTH <= 0) try {
Log.v(LOG_TAG,"Writing Frame");
long t = 1000 * (System.currentTimeMillis() - startTime);
if (t > recorder.getTimestamp()) {
recorder.setTimestamp(t);
}
if(addFilter) {
filter.push(yuvImage);
Frame frame2;
while ((frame2 = filter.pull()) != null) {
recorder.record(frame2, filter.getPixelFormat());
}
} else {
recorder.record(yuvImage);
}
} catch (FFmpegFrameRecorder.Exception | FrameFilter.Exception e) {
Log.v(LOG_TAG,e.getMessage());
e.printStackTrace();
}
}
}
}
@Override
public void onClick(View v) {
if (!recording) {
startRecording();
Log.w(LOG_TAG, "Start Button Pushed");
btnRecorderControl.setText("Stop");
} else {
// This will trigger the audio recording loop to stop and then set isRecorderStart = false;
stopRecording();
Log.w(LOG_TAG, "Stop Button Pushed");
btnRecorderControl.setText("Start");
}
}
}