Simultaneous TextureView and SurfaceView Android Camera

Question

I can display a preview of the camera video properly with a TextureView:

package com.example.camerasurfacetexture;

import java.io.IOException;

import android.app.Activity;
import android.graphics.SurfaceTexture;
import android.hardware.Camera;
import android.os.Bundle;
import android.util.Log;
import android.view.Gravity;
import android.view.TextureView;
import android.view.TextureView.SurfaceTextureListener;
import android.widget.FrameLayout;

public class MainActivity extends Activity implements SurfaceTextureListener
{

    private Camera mCamera = null;
    private TextureView mTextureView = null;

    @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)
    {
        Log.i("onSurfaceTextureAvailable", "onSurfaceTextureAvailable");

        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)
    {
        Log.i("onSurfaceTextureDestroyed", "onSurfaceTextureDestroyed");
        mCamera.stopPreview();
        mCamera.release();
        return true;
    }

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

and with a SurfaceView:

package com.example.cameratest;

import android.app.Activity;
import android.hardware.Camera;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.widget.Toast;

public class MainActivity extends Activity
{
    private SurfaceView preview = null;
    private SurfaceHolder previewHolder = null;
    private Camera camera = null;
    private boolean inPreview = false;
    private boolean cameraConfigured = false;

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

        setContentView(R.layout.activity_main);

        preview = (SurfaceView) findViewById(R.id.cpPreview);
        previewHolder = preview.getHolder();
        previewHolder.addCallback(surfaceCallback);
        previewHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

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

        camera = Camera.open();
        startPreview();
    }

    @Override
    public void onPause()
    {
        if (inPreview)
        {
            camera.stopPreview();
        }

        camera.release();
        camera = null;
        inPreview = false;

        super.onPause();
    }

    private Camera.Size getBestPreviewSize(int width, int height,
            Camera.Parameters parameters)
    {
        Camera.Size result = null;

        for (Camera.Size size : parameters.getSupportedPreviewSizes())
        {
            if (size.width <= width && size.height <= height)
            {
                if (result == null)
                {
                    result = size;
                }
                else
                {
                    int resultArea = result.width * result.height;
                    int newArea = size.width * size.height;

                    if (newArea > resultArea)
                    {
                        result = size;
                    }
                }
            }
        }

        return (result);
    }

    private void initPreview(int width, int height)
    {
        if (camera != null && previewHolder.getSurface() != null)
        {
            try
            {
                camera.setPreviewDisplay(previewHolder);
            }
            catch (Throwable t)
            {
                Log.e("PreviewDemo-surfaceCallback",
                        "Exception in setPreviewDisplay()", t);
                Toast.makeText(MainActivity.this, t.getMessage(),
                        Toast.LENGTH_LONG).show();
            }

            if (!cameraConfigured)
            {
                Camera.Parameters parameters = camera.getParameters();
                Camera.Size size = getBestPreviewSize(width, height, parameters);

                if (size != null)
                {
                    parameters.setPreviewSize(size.width, size.height);
                    camera.setParameters(parameters);
                    cameraConfigured = true;
                }
            }
        }
    }

    private void startPreview()
    {
        if (cameraConfigured && camera != null)
        {
            camera.startPreview();
            inPreview = true;
        }
    }

    SurfaceHolder.Callback surfaceCallback = new SurfaceHolder.Callback()
    {
        public void surfaceCreated(SurfaceHolder holder)
        {
            // no-op -- wait until surfaceChanged()
        }

        public void surfaceChanged(SurfaceHolder holder, int format, int width,
                int height)
        {
            initPreview(width, height);
            startPreview();
        }

        public void surfaceDestroyed(SurfaceHolder holder)
        {
            // no-op
        }
    };
}

but if I try to do both at the same time:

package com.example.multiplecamerapreviewtest;

import java.io.IOException;

import android.app.Activity;
import android.graphics.SurfaceTexture;
import android.hardware.Camera;
import android.os.Bundle;
import android.util.Log;
import android.view.Gravity;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.TextureView;
import android.view.TextureView.SurfaceTextureListener;
import android.widget.FrameLayout;
import android.widget.Toast;

public class MainActivity extends Activity implements SurfaceTextureListener
{
    private SurfaceView svPreview = null;
    private SurfaceHolder previewHolder = null;
    private Camera mCamera = null;
    private boolean inPreview = false;
    private boolean cameraConfigured = false;

    private TextureView tvPreview = null;

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

        setContentView(R.layout.activity_main);

        svPreview = (SurfaceView) findViewById(R.id.svPreview);
        previewHolder = svPreview.getHolder();
        previewHolder.addCallback(surfaceCallback);
        previewHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

//        mTextureView = new TextureView(this);
        tvPreview = (TextureView) findViewById(R.id.tvPreview);
        tvPreview.setSurfaceTextureListener(this);

//        setContentView(mTextureView);
    }

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

        mCamera = Camera.open();
        startPreview();
    }

    @Override
    public void onPause()
    {
        if (inPreview)
        {
            mCamera.stopPreview();
        }

        mCamera.release();
        mCamera = null;
        inPreview = false;

        super.onPause();
    }

    private Camera.Size getBestPreviewSize(int width, int height,
            Camera.Parameters parameters)
    {
        Camera.Size result = null;

        for (Camera.Size size : parameters.getSupportedPreviewSizes())
        {
            if (size.width <= width && size.height <= height)
            {
                if (result == null)
                {
                    result = size;
                }
                else
                {
                    int resultArea = result.width * result.height;
                    int newArea = size.width * size.height;

                    if (newArea > resultArea)
                    {
                        result = size;
                    }
                }
            }
        }

        return (result);
    }

    private void initPreview(int width, int height)
    {
        if (mCamera != null && previewHolder.getSurface() != null)
        {
            try
            {
                mCamera.setPreviewDisplay(previewHolder);
            }
            catch (Throwable t)
            {
                Log.e("PreviewDemo-surfaceCallback",
                        "Exception in setPreviewDisplay()", t);
                Toast.makeText(MainActivity.this, t.getMessage(),
                        Toast.LENGTH_LONG).show();
            }

            if (!cameraConfigured)
            {
                Camera.Parameters parameters = mCamera.getParameters();
                Camera.Size size = getBestPreviewSize(width, height, parameters);

                if (size != null)
                {
                    parameters.setPreviewSize(size.width, size.height);
                    mCamera.setParameters(parameters);
                    cameraConfigured = true;
                }
            }
        }
    }

    private void startPreview()
    {
        if (cameraConfigured && mCamera != null)
        {
            mCamera.startPreview();
            inPreview = true;
        }
    }

    SurfaceHolder.Callback surfaceCallback = new SurfaceHolder.Callback()
    {
        public void surfaceCreated(SurfaceHolder holder)
        {
            // no-op -- wait until surfaceChanged()
        }

        public void surfaceChanged(SurfaceHolder holder, int format, int width,
                int height)
        {
            initPreview(width, height);
            startPreview();
        }

        public void surfaceDestroyed(SurfaceHolder holder)
        {
            // no-op
        }
    };


    @Override
    public void onSurfaceTextureAvailable(SurfaceTexture surface, int width,
            int height)
    {
        Log.i("onSurfaceTextureAvailable", "onSurfaceTextureAvailable");

        mCamera = Camera.open();

        Camera.Size previewSize = mCamera.getParameters().getPreviewSize();
        tvPreview.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)
    {
        Log.i("onSurfaceTextureDestroyed", "onSurfaceTextureDestroyed");
        mCamera.stopPreview();
        mCamera.release();
        return true;
    }

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

I get a "Fail to connect to camera service" exception when calling mCamera.setPreviewTexture().

According to the documentation (http://developer.android.com/reference/android/hardware/Camera.html#setPreviewDisplay%28android.view.SurfaceHolder%29), this is the expected behavior:

setPreviewDisplay()
 Setting a preview surface will un-set any preview surface texture that was set via setPreviewTexture(SurfaceTexture).

(and vice-versa). Is there anything I can do to get these both displaying at the same time?

score 2 · Answer 1 · answered Dec 11 '14 at 16:51

Send the Camera output to a SurfaceTexture, then render the texture wherever you like using GLES.

See e.g. the "texture from camera" activity in Grafika.

This requires some EGL management and a basic familiarity with GLES, though you can get pretty far just using the code in Grafika. This approach will get you much better performance than manipulating pixels with the NDK, because the GPU does all the work.

score 0 · Answer 2 · edited May 23 '17 at 12:31

0

Camera is a shared hardware resource. I don't think you can access it (Camera.open()) more than once even within the same application i.e even within the same process with same user id. How about accessing the buffers for camera preview natively and then reading bytes from those buffers to render them on as many TextureViews or SurfaceViews or VideoViews as you wish?

Edited:

NDK Resource: How do I get the raw Android camera buffer in C using JNI?

edited May 23 '17 at 12:31

Community

1
1

answered Feb 06 '14 at 16:27

VJ Vélan Solutions

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What do you mean "access the buffers natively"? – David Doria Feb 06 '14 at 16:41
I mean using NDK to access the frame buffers directly. – VJ Vélan Solutions Feb 06 '14 at 18:13
You don't happen to have a pointer to an example of how to do that, do you? – David Doria Feb 07 '14 at 00:44
Look at my edited answer for a link. That question has an accepted answer. I have not verified the solution myself. But since it's accepted and +vely voted on, i am assuming that will lead you in the right direction. – VJ Vélan Solutions Feb 07 '14 at 01:08

Simultaneous TextureView and SurfaceView Android Camera

2 Answers2