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Recording Live OpenCV Processing on Android

由 本小妞迷上赌 提交于 2019-11-27 13:15:53

I've solved a similar problem by creating a MediaRecorder and passing it to a OpenCV CameraBridgeViewBase, which I've modified as follows.

protected MediaRecorder mRecorder;
protected Surface mSurface = null;

public void setRecorder(MediaRecorder rec) {
    mRecorder = rec;
    if (mRecorder != null) {
        mSurface = mRecorder.getSurface();
    }

and

protected void deliverAndDrawFrame(CvCameraViewFrame frame) {
    Mat modified;

    if (mListener != null) {
        modified = mListener.onCameraFrame(frame);
    } else {
        modified = frame.rgba();
    }

    boolean bmpValid = true;
    if (modified != null) {
        try {
            Utils.matToBitmap(modified, mCacheBitmap);
        } catch(Exception e) {
            Log.e(TAG, "Mat type: " + modified);
            Log.e(TAG, "Bitmap type: " + mCacheBitmap.getWidth() + "*" + mCacheBitmap.getHeight());
            Log.e(TAG, "Utils.matToBitmap() throws an exception: " + e.getMessage());
            bmpValid = false;
        }
    }

    if (bmpValid && mCacheBitmap != null) {
        Canvas canvas;

        if (mRecorder != null) {
            canvas = mSurface.lockCanvas(null);

            canvas.drawColor(0, android.graphics.PorterDuff.Mode.CLEAR);
            Log.d(TAG, "mStretch value: " + mScale);

            if (mScale != 0) {
                canvas.drawBitmap(mCacheBitmap, new Rect(0,0,mCacheBitmap.getWidth(), mCacheBitmap.getHeight()),
                     new Rect((int)((canvas.getWidth() - mScale*mCacheBitmap.getWidth()) / 2),
                     (int)((canvas.getHeight() - mScale*mCacheBitmap.getHeight()) / 2),
                     (int)((canvas.getWidth() - mScale*mCacheBitmap.getWidth()) / 2 + mScale*mCacheBitmap.getWidth()),
                     (int)((canvas.getHeight() - mScale*mCacheBitmap.getHeight()) / 2 + mScale*mCacheBitmap.getHeight())), null);
            } else {
                 canvas.drawBitmap(mCacheBitmap, new Rect(0,0,mCacheBitmap.getWidth(), mCacheBitmap.getHeight()),
                     new Rect((canvas.getWidth() - mCacheBitmap.getWidth()) / 2,
                     (canvas.getHeight() - mCacheBitmap.getHeight()) / 2,
                     (canvas.getWidth() - mCacheBitmap.getWidth()) / 2 + mCacheBitmap.getWidth(),
                     (canvas.getHeight() - mCacheBitmap.getHeight()) / 2 + mCacheBitmap.getHeight()), null);
            }

            if (mFpsMeter != null) {
                mFpsMeter.measure();
                mFpsMeter.draw(canvas, 20, 30);
            }
            mSurface.unlockCanvasAndPost(canvas);
        } 

    }

    ...

}

I've left the original part of deliverAndDrawFrame as is, so that it keeps displaying the output to the original surface. This way I can process images from a camera by implementing onCameraFrame in MainActivity and save the resulting images to a video, without the need for ffmpeg.

EDIT I've set up the MediaRecorder as follows

recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
recorder.setVideoSource(MediaRecorder.VideoSource.SURFACE);

CamcorderProfile cpHigh = CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH);
recorder.setProfile(cpHigh);
recorder.setOutputFile("out.mp4");
recorder.setVideoSize(mOpenCvCameraView.mFrameWidth, mOpenCvCameraView.mFrameHeight);

recorder.setOnInfoListener(this);
recorder.setOnErrorListener(this);
recorder.prepare();

register it with the OpenCvCameraView

mOpenCvCameraView.setRecorder(recorder);

and start recording

recorder.start();

Try to compile FFMPEG for Android for live video processing. Integration with android and openCV,this link will help:

http://www.jayrambhia.com/blog/ffmpeg-opencv-android

@HaDang pointed me to these links:

http://www.walking-productions.com/notslop/2013/01/16/android-live-streaming-courtesy-of-javacv-and-ffmpeg/

https://code.google.com/p/javacv/source/browse/samples/RecordActivity.java

That example uses a Java wrapper of FFMPEG to do the video recording. This project is a pretty useful starting point for anybody wanting to do the same: https://github.com/vanevery/JavaCV_0.3_stream_test

I took that above project and hammered it into my example. It's very messy, but it works:

package com.example.videotest;


import java.io.File;
import java.io.IOException;
import java.nio.ShortBuffer;
import java.util.List;

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.android.OpenCVLoader;
import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
import org.opencv.core.Mat;
import org.opencv.core.Scalar;
import org.opencv.imgproc.Imgproc;

import com.googlecode.javacv.FFmpegFrameRecorder;
import com.googlecode.javacv.FrameRecorder.Exception;
import com.googlecode.javacv.cpp.opencv_core.IplImage;

import android.app.Activity;
import android.media.AudioFormat;
import android.media.AudioRecord;
import android.media.MediaRecorder;
import android.media.MediaScannerConnection;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.SurfaceView;
import android.view.View;
import android.view.WindowManager;
import android.widget.Toast;

public class MainActivity extends Activity implements CvCameraViewListener2{

    private CameraView cameraView;
    private Mat edgesMat;
    private final Scalar greenScalar = new Scalar(0,255,0);
    private int resolutionIndex = 0;

    private IplImage videoImage = null;

    boolean recording = false;
    private volatile FFmpegFrameRecorder recorder;

    private int sampleAudioRateInHz = 44100;
    private int imageWidth = 320;
    private int imageHeight = 240;
    private int frameRate = 30;

    private Thread audioThread;
    volatile boolean runAudioThread = true;
    private AudioRecord audioRecord;
    private AudioRecordRunnable audioRecordRunnable;

    private String ffmpeg_link;

    long startTime = 0;

    private String LOG_TAG = "VideoTest";

    private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
        @Override
        public void onManagerConnected(int status) {
            switch (status) {
            case LoaderCallbackInterface.SUCCESS:
                Log.i("VideoTest", "OpenCV loaded successfully");
                cameraView.enableView();
                break;
            default:
                super.onManagerConnected(status);
                break;
            }
        }
    };


    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

        setContentView(R.layout.activity_main);

        cameraView = (CameraView) findViewById(R.id.cameraView);
        cameraView.setVisibility(SurfaceView.VISIBLE);
        cameraView.setCvCameraViewListener(this);
    }

    private void initRecorder() {
        Log.w(LOG_TAG,"initRecorder");

        int depth = com.googlecode.javacv.cpp.opencv_core.IPL_DEPTH_8U;
        int channels = 4;

        // if (yuvIplimage == null) {
        // Recreated after frame size is set in surface change method
        videoImage = IplImage.create(imageWidth, imageHeight, depth, channels);
        //yuvIplimage = IplImage.create(imageWidth, imageHeight, IPL_DEPTH_32S, 2);

        Log.v(LOG_TAG, "IplImage.create");
        // }

        File videoFile = new File(getExternalFilesDir(null), "VideoTest/images/video.mp4");
        boolean mk = videoFile.getParentFile().mkdirs();
        Log.v(LOG_TAG, "Mkdir: " + mk);

        boolean del = videoFile.delete();
        Log.v(LOG_TAG, "del: " + del);

        try {
            boolean created = videoFile.createNewFile();
            Log.v(LOG_TAG, "Created: " + created);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        ffmpeg_link = videoFile.getAbsolutePath();
        recorder = new FFmpegFrameRecorder(ffmpeg_link, imageWidth, imageHeight, 1);
        Log.v(LOG_TAG, "FFmpegFrameRecorder: " + ffmpeg_link + " imageWidth: " + imageWidth + " imageHeight " + imageHeight);

        recorder.setFormat("mp4");
        Log.v(LOG_TAG, "recorder.setFormat(\"mp4\")");

        recorder.setSampleRate(sampleAudioRateInHz);
        Log.v(LOG_TAG, "recorder.setSampleRate(sampleAudioRateInHz)");

        // re-set in the surface changed method as well
        recorder.setFrameRate(frameRate);
        Log.v(LOG_TAG, "recorder.setFrameRate(frameRate)");

        // Create audio recording thread
        audioRecordRunnable = new AudioRecordRunnable();
        audioThread = new Thread(audioRecordRunnable);
    }

    @Override
    public void onPause()
    {
        super.onPause();
        if (cameraView != null){
            cameraView.disableView();
        }
    }

    @Override
    public void onResume()
    {
        super.onResume();
        OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_3, this, mLoaderCallback);
    }

    public void onDestroy() {
        super.onDestroy();
        if (cameraView != null)
            cameraView.disableView();
    }

    public void onCameraViewStarted(int width, int height) {
        edgesMat = new Mat();
    }

    public void onCameraViewStopped() {
        if (edgesMat != null)
            edgesMat.release();

        edgesMat = null;
    }

    public Mat onCameraFrame(CvCameraViewFrame inputFrame) {

        Mat rgba = inputFrame.rgba();
        org.opencv.core.Size sizeRgba = rgba.size();

        int rows = (int) sizeRgba.height;
        int cols = (int) sizeRgba.width;

        int left = cols / 8;
        int top = rows / 8;
        int width = cols * 3 / 4;
        int height = rows * 3 / 4;

        //get sub-image
        Mat rgbaInnerWindow = rgba.submat(top, top + height, left, left + width);

        //create edgesMat from sub-image
        Imgproc.Canny(rgbaInnerWindow, edgesMat, 100, 100);

        Mat colorEdges = new Mat();
        Mat killMe = colorEdges;
        edgesMat.copyTo(colorEdges);
        Imgproc.cvtColor(colorEdges, colorEdges, Imgproc.COLOR_GRAY2BGRA);


        colorEdges = colorEdges.setTo(greenScalar, edgesMat);
        colorEdges.copyTo(rgbaInnerWindow, edgesMat);

        killMe.release();
        colorEdges.release();

        rgbaInnerWindow.release();

        if(recording){
            byte[] byteFrame = new byte[(int) (rgba.total() * rgba.channels())];
            rgba.get(0, 0, byteFrame);
            onFrame(byteFrame);
        }

        return rgba;
    }

    public void stopRecording() {
        // This should stop the audio thread from running
        runAudioThread = false;

        if (recorder != null) {
            Log.v(LOG_TAG,"Finishing recording, calling stop and release on recorder");
            try {
                recorder.stop();
                recorder.release();
            } catch (FFmpegFrameRecorder.Exception e) {
                e.printStackTrace();
            }
            recorder = null;
        }

        MediaScannerConnection.scanFile(MainActivity.this, new String[]{ffmpeg_link}, null, null);
    }


    public void changeResolution(View v){
        List<android.hardware.Camera.Size> cameraResolutionList = cameraView.getResolutionList();
        resolutionIndex++;
        if(resolutionIndex >= cameraResolutionList.size()){
            resolutionIndex = 0;
        }

        android.hardware.Camera.Size resolution = cameraResolutionList.get(resolutionIndex);
        cameraView.setResolution(resolution.width, resolution.height);
        resolution = cameraView.getResolution();
        String caption = Integer.valueOf(resolution.width).toString() + "x" + Integer.valueOf(resolution.height).toString();
        Toast.makeText(this, caption, Toast.LENGTH_SHORT).show();

        imageWidth = resolution.width;
        imageHeight = resolution.height;

        frameRate = cameraView.getFrameRate();

        initRecorder();
    }

    int frames = 0;

    private void onFrame(byte[] data){

        if (videoImage != null && recording) {
            long videoTimestamp = 1000 * (System.currentTimeMillis() - startTime);

            // Put the camera preview frame right into the yuvIplimage object
            videoImage.getByteBuffer().put(data);

            try {

                // Get the correct time
                recorder.setTimestamp(videoTimestamp);

                // Record the image into FFmpegFrameRecorder
                recorder.record(videoImage);

                frames++;

                Log.i(LOG_TAG, "Wrote Frame: " + frames);

            } 
            catch (FFmpegFrameRecorder.Exception e) {
                Log.v(LOG_TAG,e.getMessage());
                e.printStackTrace();
            }
        }

    }

    public void startVideo(View v){

        recording = !recording;

        Log.i(LOG_TAG, "Recording: " + recording);

        if(recording){
            startTime = System.currentTimeMillis();
            try {
                recorder.start();

                Log.i(LOG_TAG, "STARTED RECORDING.");

            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        else{
            stopRecording();
        }
    }



    class AudioRecordRunnable implements Runnable {

        @Override
        public void run() {
            // Set the thread priority
            android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_URGENT_AUDIO);

            // Audio
            int bufferSize;
            short[] audioData;
            int bufferReadResult;

            bufferSize = AudioRecord.getMinBufferSize(sampleAudioRateInHz, 
                    AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT);
            audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, sampleAudioRateInHz, 
                    AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT, bufferSize);

            audioData = new short[bufferSize];

            Log.d(LOG_TAG, "audioRecord.startRecording()");
            audioRecord.startRecording();

            // Audio Capture/Encoding Loop
            while (runAudioThread) {
                // Read from audioRecord
                bufferReadResult = audioRecord.read(audioData, 0, audioData.length);
                if (bufferReadResult > 0) {
                    //Log.v(LOG_TAG,"audioRecord bufferReadResult: " + bufferReadResult);

                    // Changes in this variable may not be picked up despite it being "volatile"
                    if (recording) {
                        try {
                            // Write to FFmpegFrameRecorder
                            recorder.record(ShortBuffer.wrap(audioData, 0, bufferReadResult));
                        } catch (FFmpegFrameRecorder.Exception e) {
                            Log.v(LOG_TAG,e.getMessage());
                            e.printStackTrace();
                        }
                    }
                }
            }
            Log.v(LOG_TAG,"AudioThread Finished");

            /* Capture/Encoding finished, release recorder */
            if (audioRecord != null) {
                audioRecord.stop();
                audioRecord.release();
                audioRecord = null;

                MediaScannerConnection.scanFile(MainActivity.this, new String[]{ffmpeg_link}, null, null);

                Log.v(LOG_TAG,"audioRecord released");
            }
        }
    }

}

Another option that works only on Lollipop and Marshmallow is to use the new MediaProjectionManager to capture and record what's happening on your device's screen. A great example is here:

http://www.mattsnider.com/video-recording-with-mediaprojectionmanager/

It's totally independent of your device's camera and doesn't need any access to it or whatever you're doing with OpenCV. It's just recording whatever you have displayed on your screen.

标签
java
android
OpenCV
jcodec
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