android - 无法使用 Camera.takePicture 拍照

Question

我正在尝试制作一个可以拍照的 Activity ，唯一的问题是永远不会调用回调。预览会停止并出现“请稍候”对话框，因此在该部分之前一切正常。

我正在安装了 AOKP ROM 的 Galaxy S3 i9300 上进行测试。安卓版本 4.3.1

PictureTaker.java

package ...;
import everything;

public class PictureTaker extends Activity  {
    private Preview mPreview;
    Camera mCamera;
    int numberOfCameras;
    int cameraCurrentlyLocked;

    public AlertDialog diag;
    protected PowerManager.WakeLock mWakeLock;

    // The first rear facing camera
    int defaultCameraId;


    final Camera.ShutterCallback shutterCallback = new Camera.ShutterCallback() {
        @Override
        public void onShutter() {
            Log.d("Adnan", "onShutter");
        }
    };


    final Camera.PictureCallback mPicture = new Camera.PictureCallback() {
        String picPath = Environment.getExternalStorageDirectory() + "/billsterData/camTemp.jpg";

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            String TAG = "Adnan";
            diag.dismiss();

            Log.d(TAG, "Attempting to store picture...");
            final int MEDIA_TYPE_IMAGE = 100;
            File pictureFile = new File(picPath);

            if (pictureFile == null){
                Log.d(TAG, "Error creating media file, check storage permissions");
                return;
            }

            try {
                FileOutputStream fos = new FileOutputStream(pictureFile);
                fos.write(data);
                fos.close();
            } catch (FileNotFoundException e) {
                Log.d(TAG, "File not found: " + e.getMessage());
            } catch (IOException e) {
                Log.d(TAG, "Error accessing file: " + e.getMessage());
            }
        }
    };

    public void onExitPressed(View v) {
        onBackPressed();
    }

    public void takePic(View v) {
        Log.i("Adnan", "taking picture...");

        mCamera.takePicture(shutterCallback, null, mPicture);

        v.startAnimation(AnimationUtils.loadAnimation(this, R.anim.popup));

        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("Please wait");
        builder.setView(getLayoutInflater().inflate(R.layout.progress_circular, null));
        builder.setCancelable(false);
        diag = builder.create();
        diag.show();
    }



    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Hide the window title.
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.pic_taker_carry);

        // Create a RelativeLayout container that will hold a SurfaceView,
        // and set it as the content of our activity.
        mPreview = new Preview(this);
        RelativeLayout carry = (RelativeLayout)findViewById(R.id.container);

        mPreview.setLayoutParams(new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));

        carry.addView(mPreview,0);

        //setContentView(mPreview);

        // Find the total number of cameras available
        numberOfCameras = Camera.getNumberOfCameras();

        // Find the ID of the default camera
        Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
        for (int i = 0; i < numberOfCameras; i++) {
            Camera.getCameraInfo(i, cameraInfo);
            if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_BACK) {
                defaultCameraId = i;
            }
        }
    }

    @Override
    protected void onResume() {
        super.onResume();

        final PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
        this.mWakeLock = pm.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK, "My Tag");
        this.mWakeLock.acquire();

        // Open the default i.e. the first rear facing camera.
        mCamera = Camera.open();
        cameraCurrentlyLocked = defaultCameraId;
        mPreview.setCamera(mCamera);
    }

    @Override
    protected void onPause() {
        super.onPause();

        this.mWakeLock.release();

        // Because the Camera object is a shared resource, it's very
        // important to release it when the activity is paused.
        if (mCamera != null) {
            mPreview.setCamera(null);
            mCamera.release();
            mCamera = null;
        }
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        return true;
    }
}

预览.java

package ...;

import everything

public class Preview extends ViewGroup implements SurfaceHolder.Callback {
    private final String TAG = "Preview";

    SurfaceView mSurfaceView;
    SurfaceHolder mHolder;
    Size mPreviewSize;
    List<Size> mSupportedPreviewSizes;
    Camera mCamera;

    public Preview(Context context) {
        super(context);

        mSurfaceView = new SurfaceView(context);
        addView(mSurfaceView);

        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed.
        mHolder = mSurfaceView.getHolder();
        mHolder.addCallback(this);
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    public void setCamera(Camera camera) {
        mCamera = camera;
        if (mCamera != null) {
            mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
            requestLayout();
        }
    }

    public void switchCamera(Camera camera) {
        setCamera(camera);
        try {
            camera.setPreviewDisplay(mHolder);
        } catch (IOException exception) {
            Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
        }
        Camera.Parameters parameters = camera.getParameters();
        parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
        requestLayout();

        camera.setParameters(parameters);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        // We purposely disregard child measurements because act as a
        // wrapper to a SurfaceView that centers the camera preview instead
        // of stretching it.
        final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
        final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
        setMeasuredDimension(width, height);

        if (mSupportedPreviewSizes != null) {
            mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
        }
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        if (changed && getChildCount() > 0) {
            final View child = getChildAt(0);

            final int width = r - l;
            final int height = b - t;

            int previewWidth = width;
            int previewHeight = height;
            if (mPreviewSize != null) {
                previewWidth = mPreviewSize.width;
                previewHeight = mPreviewSize.height;
            }

            // Center the child SurfaceView within the parent.
            if (width * previewHeight > height * previewWidth) {
                final int scaledChildWidth = previewWidth * height / previewHeight;
                child.layout((width - scaledChildWidth) / 2, 0,
                        (width + scaledChildWidth) / 2, height);
            } else {
                final int scaledChildHeight = previewHeight * width / previewWidth;
                child.layout(0, (height - scaledChildHeight) / 2,
                        width, (height + scaledChildHeight) / 2);
            }
        }
    }

    public void surfaceCreated(SurfaceHolder holder) {
        // The Surface has been created, acquire the camera and tell it where
        // to draw.
        try {
            if (mCamera != null) {
                mCamera.setPreviewDisplay(holder);
            }
        } catch (IOException exception) {
            Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
        }
    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        // Surface will be destroyed when we return, so stop the preview.
        if (mCamera != null) {
            mCamera.stopPreview();
        }
    }


    private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) {
        final double ASPECT_TOLERANCE = 0.1;
        double targetRatio = (double) w / h;
        if (sizes == null) return null;

        Size optimalSize = null;
        double minDiff = Double.MAX_VALUE;

        int targetHeight = h;

        // Try to find an size match aspect ratio and size
        for (Size size : sizes) {
            double ratio = (double) size.width / size.height;
            if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
            if (Math.abs(size.height - targetHeight) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - targetHeight);
            }
        }

        // Cannot find the one match the aspect ratio, ignore the requirement
        if (optimalSize == null) {
            minDiff = Double.MAX_VALUE;
            for (Size size : sizes) {
                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }
        }
        return optimalSize;
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        // Now that the size is known, set up the camera parameters and begin
        // the preview.
        try {
            mCamera.stopPreview();
        } catch (Exception e ) {

        }

        Camera.Parameters parameters = mCamera.getParameters();
        parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
        parameters.setPictureFormat(PixelFormat.JPEG);
        parameters.setJpegQuality(80);

        requestLayout();

        mCamera.setParameters(parameters);
        mCamera.startPreview();
    }

}

logcat中的一些相关行:

01-20 17:13:56.544   22594-5071/? E/exynos_param﹕ exynos_param_string_get: Unable to get data for key recording-hint
01-20 17:13:56.544   22594-5071/? E/exynos_param﹕ exynos_param_string_get: Unable to get data for key focus-areas
01-20 17:13:56.574   22594-5973/? E/exynos_camera﹕ exynos_camera_capture_thread: Starting thread
01-20 17:13:56.729  22594-22631/? E/exynos_camera﹕ Preview thread was already stopped!
01-20 17:13:56.739  22594-25719/? E/exynos_param﹕ exynos_param_data_set: Mismatching types for key horizontal-view-angle
01-20 17:13:56.744  22594-25719/? E/exynos_param﹕ exynos_param_string_get: Unable to get data for key recording-hint
01-20 17:13:56.744  22594-25719/? E/exynos_param﹕ exynos_param_string_get: Unable to get data for key focus-areas
01-20 17:13:56.744   22594-5974/? E/exynos_camera﹕ exynos_camera_preview_thread: Starting thread
01-20 17:13:58.709   22594-5975/? E/exynos_camera﹕ exynos_camera_picture_thread: Starting thread
01-20 17:13:58.804   22594-5973/? E/exynos_camera﹕ s5c73m3_interleaved_decode: Invalid jpeg start
01-20 17:13:58.804   22594-5973/? E/exynos_camera﹕ exynos_camera_capture: Unable to decode S5C73M3 interleaved
01-20 17:13:58.804   22594-5973/? E/exynos_camera﹕ exynos_camera_capture_thread: Unable to capture
01-20 17:14:15.479   22594-5974/? E/exynos_camera﹕ exynos_camera_preview_thread: Exiting thread
01-20 17:14:15.534   22594-5975/? E/exynos_camera﹕ exynos_camera_picture_thread: Exiting thread
01-20 17:14:15.534   22594-5973/? E/exynos_camera﹕ exynos_camera_capture_thread: Exiting thread

注意这个:

01-20 17:13:58.804   22594-5973/? E/exynos_camera﹕ s5c73m3_interleaved_decode: Invalid jpeg start

Answer 1

我在使用 CyanogenMod 10.1 及更高版本的 Galaxy S3 (I9300) 上遇到了同样的问题。今天我找到了解决方案。我认为这是 AOPK 代码中的问题。

您必须确保预览尺寸和图片尺寸的纵横比相等。

尝试使用此代码获取图片大小而不会出现此问题:

private Camera.Size getBestPictureSize(List<Camera.Size> pictureSizes, int maxWidth, Size previewSize) {
    Comparator<Camera.Size> cmp = new Comparator<Camera.Size>() {
        public int compare(Camera.Size size_1, Camera.Size size_2) {
            return Integer.valueOf(size_1.width).compareTo(Integer.valueOf(size_2.width));
        }
    };
    final double ASPECT_TOLERANCE = 0.1;
    double targetAspect = (double)previewSize.width / (double)previewSize.height;

    ArrayList<Camera.Size> matchedPictureSizes = new ArrayList<Camera.Size>();


    for(Size pictureSize : pictureSizes) {
        double pictureAspect = (double)pictureSize.width / (double)pictureSize.height;

        if(pictureSize.width <= maxWidth && Math.abs(targetAspect - pictureAspect) < ASPECT_TOLERANCE) {
            matchedPictureSizes.add(pictureSize);
        }
    }

    Camera.Size bestPictureSize;
    if(!matchedPictureSizes.isEmpty()) {
        bestPictureSize = Collections.max(matchedPictureSizes, cmp);
    } else {
        bestPictureSize = Collections.max(pictureSizes, cmp);
    }

    return bestPictureSize;
}

希望这段代码能解决您的问题。