如何使相机可以使用连拍模式

Question

我正在尝试构建一个带有相机连拍模式的小型照片应用程序。主要思想是每 0.3 秒拍摄一张照片并将照片存储在数组中，直到拍摄最后一张照片。应指定要​​拍摄的照片数量。

我只能每2秒拍一张照片。作为最短间隔。然后，当将图片写入存储时，应用程序就会崩溃。

有人知道如何实现这个吗？这是我的代码：

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.view.View.OnClickListener;

public class CamaeaView extends Activity implements SurfaceHolder.Callback, OnClickListener {

    static final int FOTO_MODE = 1;
    private static final String TAG = "Test";
    Camera mCamera;
    boolean mPreviewRunning = false;
    private Context mContext = this;
    ArrayList<Object> listImage = null;
    public static ArrayList<Object> List1[];

    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        Log.e(TAG, "onCreate");

        @SuppressWarnings("unused")
        Bundle extras = getIntent().getExtras();

        getWindow().setFormat(PixelFormat.TRANSLUCENT);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.main);
        mSurfaceView = (SurfaceView) findViewById(R.id.surface_camera);
        mSurfaceView.setOnClickListener(this);
        mSurfaceHolder = mSurfaceView.getHolder();
        mSurfaceHolder.addCallback(this);
        mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
    }

    Camera.PictureCallback mPictureCallback = new Camera.PictureCallback() {
        public void onPictureTaken(byte[] imageData, Camera c) {
            Log.d("Start: ","Imagelist");

            Intent mIntent = new Intent();
            listImage.add(StoreByteImage(imageData));
            SaveImage(listImage);
            mCamera.startPreview();

            setResult(FOTO_MODE, mIntent);
            finish();

        }
    };

    protected void onResume() {
        Log.d(TAG, "onResume");
        super.onResume();
    }

    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
    }

    protected void onStop() {
        Log.e(TAG, "onStop");
        super.onStop();
    }

    public void surfaceCreated(SurfaceHolder holder) {
        Log.d(TAG, "surfaceCreated");
        mCamera = Camera.open();

    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        Log.d(TAG, "surfaceChanged");

        // XXX stopPreview() will crash if preview is not running
        if (mPreviewRunning) {
            mCamera.stopPreview();
        }

        Camera.Parameters p = mCamera.getParameters();
        p.setPreviewSize(w, h);
        p.setPictureSize(1024, 768);
        p.getSupportedPictureFormats();
        p.setPictureFormat(PixelFormat.JPEG);
        mCamera.setParameters(p);
        try {
            mCamera.setPreviewDisplay(holder);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        mCamera.startPreview();
        mPreviewRunning = true;
    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        Log.e(TAG, "surfaceDestroyed");
        mCamera.stopPreview();
        mPreviewRunning = false;
        mCamera.release();
    }

    private SurfaceView mSurfaceView;
    private SurfaceHolder mSurfaceHolder;

    public void onClick(View arg0) {
        int i = 0;
        while (i < 4) {

            mCamera.takePicture(null, mPictureCallback, mPictureCallback);
            i = i + 1;
            try {
                Thread.sleep(3000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

    public static Object StoreByteImage(byte[] imageData) {

        Object obj = null;
        try {
            ByteArrayInputStream bis = new ByteArrayInputStream(imageData);
            ObjectInputStream objImageData = new ObjectInputStream(bis);
            obj = objImageData.readObject();

        } catch (IOException ex) {
            // TODO: Handle the exception
        } catch (ClassNotFoundException ex) {
            // TODO: Handle the exception
        }
        return obj;

    }

    public static Object createImagesArray(byte[] imageData) {

        Object obj = null;
        try {
            ByteArrayInputStream bis = new ByteArrayInputStream(imageData);
            ObjectInputStream objImageData = new ObjectInputStream(bis);
            obj = objImageData.readObject();

        } catch (IOException ex) {
            // TODO: Handle the exception
        } catch (ClassNotFoundException ex) {
            // TODO: Handle the exception
        }
        return obj;

    }

    public static boolean SaveImage(List<Object> listImage) {

        FileOutputStream outStream = null;
        Log.d("ListSize: ", Integer.toString(listImage.size()));
        Iterator<Object> itList = listImage.iterator();
        byte[] imageBytes = null;
        while (itList.hasNext()) {

            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            try {
                ObjectOutputStream oos = new ObjectOutputStream(bos);
                oos.writeObject(listImage);
                oos.flush();
                oos.close();
                bos.close();
                imageBytes = bos.toByteArray();
            } catch (IOException ex) {
                // TODO: Handle the exception
            }

            try {
                // Write to SD Card
                outStream = new FileOutputStream(String.format(
                        "/sdcard/DCIM/%d.jpg", System.currentTimeMillis())); // <9>
                outStream.write(imageBytes);
                outStream.close();

            } catch (FileNotFoundException e) { // <10>
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
            }
        }
        Log.d(TAG, "onPictureTaken - jpeg");

        return true;
    }

}

评论中的错误：

ERROR/MemoryHeapBase(1382): error opening /dev/pmem_camera: No such file or directory 
ERROR/QualcommCameraHardware(1382): failed to construct master heap for pmem pool /dev/pmem_camera 
ERROR/QualcommCameraHardware(1382): initRaw X failed with pmem_camera, trying with pmem_adsp

Answer 1

AFAIK，在第一张照片完成之前，您无法拍摄另一张照片。消除 for 循环和 Thread.sleep()。在mPictureCallback中拍摄下一张照片。

主要思想是每 0.3 秒拍摄一张照片并将照片存储在数组中，直到拍摄最后一张照片。

“0.3秒”目标比大多数设备处理图像的速度要快，并且您可能没有足够的堆空间来容纳图像数组。我怀疑您必须将每个图像通过 AsyncTask 传入磁盘，这样您就可以释放堆空间，同时又不会占用主应用程序线程。

Answer 2

您可以尝试在预分配的字节数组中捕获后续预览帧。
请参阅以下方法：

http: //developer.android.com/reference/android/hardware/Camera.html#addCallbackBuffer(byte[])
http://developer.android. com/reference/android/hardware/Camera.html#setPreviewCallbackWithBuffer(android.hardware.Camera.PreviewCallback)

...或 http://developer.android.com/参考/android/hardware/Camera.html#setOneShotPreviewCallback(android.hardware.Camera.PreviewCallback)以更好地控制时间。