Question

I am trying to render camera preview using SurfaceTexture. I read the document but unable to understand how it works.

Can anyone provide one sample example(very basic one) or link which uses SurfaceTexture to preview camera. I googled this but not found what I am looking for.

Thanks in advance.

Answer 1

If you want to use the Camera with TextureSurface you can implement SurfaceTextureListener interface. You’ll have to implement 4 methods:

1) onSurfaceTextureAvailable – Here you setup your camera

2)onSurfaceTextureSizeChanged – In your case, the Android’s camera will handle this method

3)onSurfaceTextureDestroyed – Here you destroy all camera stuff.

4) onSurfaceTextureUpdated– Update your texture here when you have something to change!

Check the example below:

    public class MainActivity extends Activity implements SurfaceTextureListener{

    private Camera mCamera;
    private TextureView mTextureView;

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

        mTextureView = new TextureView(this);
        mTextureView.setSurfaceTextureListener(this);

        setContentView(mTextureView);
    }

    @Override
    public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
        mCamera = Camera.open();

        Camera.Size previewSize = mCamera.getParameters().getPreviewSize();
        mTextureView.setLayoutParams(new FrameLayout.LayoutParams(
                previewSize.width, previewSize.height, Gravity.CENTER));

        try {
            mCamera.setPreviewTexture(surface);
        } catch (IOException t) {
        }

        mCamera.startPreview();

    }

    @Override
    public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
        // Ignored, the Camera does all the work for us
    }

    @Override
    public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
        mCamera.stopPreview();
        mCamera.release();
        return true;
    }

    @Override
    public void onSurfaceTextureUpdated(SurfaceTexture surface) {
        // Update your view here!
    }
}

Two more things: Don’t forget to add the camera permissions in your project’s manifest and the SurfaceTexture is available from API 11.