Android Camera PreviewCallback not called in 4.1

徘徊边缘 提交于 2019-12-01 05:23:34

I have rewrote the code by using another tutorial. It works, but now slower. I don't know the exact reason (it may be due to leaked N7000 ROM I use, it may have a bug or this is implemented differently in 4.1, not sure)

CameraPreview.java

public class CameraPreview implements SurfaceHolder.Callback,
        Camera.PreviewCallback {
    int PreviewSizeWidth;
    int PreviewSizeHeight;
    SurfaceHolder mSurfHolder;
    Camera mCamera;

    public CameraPreview(int PreviewlayoutWidth, int PreviewlayoutHeight) {
        PreviewSizeWidth = PreviewlayoutWidth;
        PreviewSizeHeight = PreviewlayoutHeight;
    }



    @Override
    public void onPreviewFrame(byte[] data, Camera camera) {
        Parameters p = camera.getParameters();  
        int width = p.getPreviewSize().width;
        int height = p.getPreviewSize().height;

        ByteArrayOutputStream outstr = new ByteArrayOutputStream();
        Rect rect = new Rect(0, 0, width, height);
        YuvImage yuvimage = new YuvImage(data, ImageFormat.NV21, width,
                height, null);
        yuvimage.compressToJpeg(rect, 80, outstr); // outstr contains image in jpeg  
        String encodedImage = Base64.encodeToString(
                outstr.toByteArray(), Base64.DEFAULT); // this is base64 encoding of image


    }

    @Override
    public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
        Parameters parameters;
        mSurfHolder = arg0;

        parameters = mCamera.getParameters();
        parameters.setPreviewSize(PreviewSizeWidth, PreviewSizeHeight);

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

    public void surfaceCreated(SurfaceHolder arg0) {
        mCamera = Camera.open();
        try {
            // If did not set the SurfaceHolder, the preview area will be black.
            mCamera.setPreviewDisplay(arg0);
            mCamera.setPreviewCallback(this);
            Parameters p = mCamera.getParameters();
            p.setPreviewSize(PreviewSizeWidth, PreviewSizeHeight);
            mCamera.setParameters(p);
        } catch (IOException e) {
            mCamera.release();
            mCamera = null;
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder arg0) {
        mCamera.setPreviewCallback(null);
        mCamera.stopPreview();
        mCamera.release();
        mCamera = null;
    }
}

PanelActivity.java

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_panel);


    SurfaceView camView = new SurfaceView(this);
    SurfaceHolder camHolder = camView.getHolder();
    int width = 352; // must set a compatible value, otherwise it gets the default width and height
    int height = 288;

    camPreview = new CameraPreview(width, height);

    camHolder.addCallback(camPreview);
    camHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

    mainLayout = (FrameLayout) findViewById(R.id.videoview);
    mainLayout.addView(camView, new LayoutParams(width, height));

}
易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!