Android 카메라 - 앱이 NULL 표면을 전달했습니다.

Question

cam_thread를 실행할 때마다 "app passed NULL surface"오류가 표시됩니다. 이 코드는 HTC Incredible 1에서 작동합니다. 드로이드 x에서 실행되도록 약간 재구성했습니다. 그러나 나는 아직도이 오류가 발생합니다.

public class Android_Activity extends Activity 
{  
    Main_thread simulator; 
    ToggleButton togglebutton; 
    EditText ip_text; 
    SensorManager sm = null; 
    SurfaceView view; 
    Sensors_thread the_sensors=null; 
    String IP_address; 
    Android_Activity the_app; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) 
    {  
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 
     view = new SurfaceView(this);  
     sm = (SensorManager) getSystemService(SENSOR_SERVICE); 
     ip_text = (EditText) findViewById(R.id.IP_edit_txt); 
     togglebutton = (ToggleButton) findViewById(R.id.CameraButton); 
     togglebutton.setOnClickListener(new btn_listener());   
     the_app = this; 
    } 

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

    protected void onStop() 
    { 
     super.onStop(); 
     simulator.stop_simu(); 
     this.finish(); 
    } 

    private class btn_listener implements OnClickListener 
    { 
     public void onClick(View v) 
     {  
      // Perform action on clicks 
      if (togglebutton.isChecked()) 
      { 
       IP_address = ip_text.getText().toString(); 

       simulator = new Main_thread(the_app, view, sm, IP_address); 
       the_sensors = simulator.the_sensors;  
       sm.registerListener(the_sensors, 
         SensorManager.SENSOR_ORIENTATION |SensorManager.SENSOR_ACCELEROMETER, 
         SensorManager.SENSOR_DELAY_UI); 

       simulator.start(); 

       Toast.makeText(Android_Activity.this, "Start streaming" + IP_address, Toast.LENGTH_SHORT).show(); 
      } else 
      { 
       simulator.stop_simu(); 
       sm.unregisterListener(the_sensors); 
       Toast.makeText(Android_Activity.this, "Stop streaming", Toast.LENGTH_SHORT).show(); 
      } 
     } 
    } 
} 

메인 스레드

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
     package="carl.IOIO_car" 
     android:versionCode="1" 
     android:versionName="1.0"> 
      <uses-sdk android:minSdkVersion="8" /> 

    <application android:icon="@drawable/icon" android:debuggable="true" android:label="@string/app_name"> 
     <activity android:name="carl.IOIO_car.Android_Activity" 
       android:label="@string/app_name" 
        android:theme="@android:style/Theme.NoTitleBar.Fullscreen" 
        android:screenOrientation="landscape"> 
      <intent-filter> 
       <action android:name="android.intent.action.MAIN" /> 
       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity> 
    </application> 
    <uses-permission android:name="android.permission.CAMERA" /> 
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> 
    <uses-permission android:name="android.permission.INTERNET" /> 
    <uses-permission android:name="android.permission.WAKE_LOCK" /> 
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission> 
<uses-permission android:name="android.permission.UPDATE_DEVICE_STATS"></uses-permission> 
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"></uses-permission> 
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE"></uses-permission> 
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> 
    <uses-feature android:name="android.hardware.camera" /> 
    <uses-feature android:name="android.hardware.camera.autofocus" /> 
</manifest> 

package carl.IOIO_car; 

import java.io.ByteArrayOutputStream; 
import java.net.DatagramPacket; 
import java.net.DatagramSocket; 
import java.net.InetAddress; 
import java.util.List; 

import android.graphics.Bitmap; 
import android.hardware.Camera; 
import android.hardware.Camera.PreviewCallback; 
import android.util.Log; 
import android.view.SurfaceView; 

public class Cam_thread 
{ 
    Camera mCamera; 

    public static int HEADER_SIZE = 5; 
    public static int DATAGRAM_MAX_SIZE = 1450 - HEADER_SIZE; 
    int frame_nb = 0; 
    int size_packet_sent = 0; 
    InetAddress serverAddr; 
    DatagramSocket socket; 

    Bitmap mBitmap; 
    int[] mRGBData; 
    int width_ima, height_ima; 
    private static final String TAG = "IP_cam"; 

    SurfaceView parent_context; 

    private boolean STOP_THREAD; 
    String ip_address; 

    public Cam_thread(SurfaceView context, String ip) 
    { 
     parent_context = context; 

     ip_address = ip; 
    } 

    private void init() 
    { 
     try 
     {    
      serverAddr = InetAddress.getByName(ip_address); 
      socket = new DatagramSocket(); 
      if (mCamera!=null){ 
       Log.e(TAG, "Nulling camera"); 
       mCamera.stopPreview(); 
       mCamera.setPreviewCallback(null); 
       mCamera.release(); 
       mCamera=null; 
     } 
      if(mCamera == null){ 
      mCamera = Camera.open();   
      Log.e(TAG, "Setting up camera"); 
      Camera.Parameters parameters = mCamera.getParameters(); 
      //get a list of supported preview sizes and assign one 
      List<Camera.Size> previewSizes = parameters.getSupportedPreviewSizes(); 
      Camera.Size previewSize = previewSizes.get(0); 
      parameters.setPreviewSize(previewSize.width, previewSize.height); 
      //Set Frame rate 
      parameters.setPreviewFrameRate(30); 
      //Set Scene 
      List<String> modes = parameters.getSupportedSceneModes(); 
      parameters.setSceneMode(modes.get(0)); 
      //Set focus mode 
      List<String> focus = parameters.getSupportedFocusModes(); 
      parameters.setFocusMode(focus.get(0)); 
      //Apply parameters to camera object 
      mCamera.setParameters(parameters); 
      //Provide a surface 
      if(parent_context.getHolder()==null) 
       Log.e(TAG, "Its a null holder"); 
      Log.e("Debug", "Before"); 
      mCamera.setPreviewDisplay(parent_context.getHolder());   
      Log.e("Debug", "After"); 
      //Sets a call when preview data is available 
      mCamera.setPreviewCallback(new cam_PreviewCallback()); 
      Log.e(TAG, "Camera configured"); 
      //Start the preview 
      Log.e(TAG, "Starting preview"); 
      mCamera.startPreview(); 
      /* 
      parameters.setPreviewSize(320, 240); 
      parameters.setPreviewFrameRate(30); 
      parameters.setSceneMode(Camera.Parameters.SCENE_MODE_SPORTS); 
      parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO); 
      parameters.setColorEffect(Camera.Parameters.EFFECT_NONE); 
      mCamera.setParameters(parameters); 
      mCamera.setPreviewDisplay(parent_context.getHolder());   
      mCamera.setPreviewCallback(new cam_PreviewCallback());   

      Log.e(TAG, "Starting preview"); 
      mCamera.startPreview(); 
      */ 
      } 
     } 
     catch (Exception exception) 
     { 

      Log.e(TAG, "Error: ", exception); 
     } 
    } 

    public void start_thread() 
    { 
     Log.e("Cam", "Started the Cam thread"); 
     init(); 
    } 

    public void stop_thread() 
    { 
     STOP_THREAD = true; 
     if (mCamera!=null){ 
      mCamera.stopPreview(); 
      mCamera.release(); 
      mCamera=null; 
     } 
     socket.close(); 
    } 

    public void send_data_UDP() 
    { 
     Log.e(TAG, "Started sending cam data"); 
     if(mBitmap != null) 
     { 
      int size_p=0,i;  
      ByteArrayOutputStream byteStream = new ByteArrayOutputStream(); 

      mBitmap.compress(Bitmap.CompressFormat.JPEG, 50, byteStream); // !!!!!!! change compression rate to change packets size 

      byte data[] = byteStream.toByteArray(); 
      Log.e(TAG, "SIZE: " + data.length); 

      int nb_packets = (int) Math.ceil(data.length/(float)DATAGRAM_MAX_SIZE); 
      int size = DATAGRAM_MAX_SIZE; 

      /* Loop through slices */ 
      for(i = 0; i < nb_packets; i++) 
      {   
       if(i >0 && i == nb_packets-1) size = data.length - i * DATAGRAM_MAX_SIZE; 

       /* Set additional header */ 
       byte[] data2 = new byte[HEADER_SIZE + size]; 
       data2[0] = (byte)frame_nb; 
       data2[1] = (byte)nb_packets; 
       data2[2] = (byte)i; 
       data2[3] = (byte)(size >> 8); 
       data2[4] = (byte)size; 

       /* Copy current slice to byte array */ 
       System.arraycopy(data, i * DATAGRAM_MAX_SIZE, data2, HEADER_SIZE, size);   

       try 
       {   
        size_p = data2.length; 
        DatagramPacket packet = new DatagramPacket(data2, size_p, serverAddr, 9000); 
        socket.send(packet); 
        Log.e(TAG, "Sent a cam frame!"); 
       } catch (Exception e) { Log.e(TAG, "Error: ", e);} 
      } 
      frame_nb++; 

      if(frame_nb == 128) frame_nb=0; 
     } 
    }  


    /* function converting image to RGB format taken from project: ViewfinderEE368 
    * http://www.stanford.edu/class/ee368/Android/ViewfinderEE368/ 
    * 
    * Copyright (C) 2007 The Android Open Source Project 
    * 
    * Licensed under the Apache License, Version 2.0 (the "License"); 
    * you may not use this file except in compliance with the License. 
    * You may obtain a copy of the License at 
    * 
    *  http://www.apache.org/licenses/LICENSE-2.0 
    * 
    * Unless required by applicable law or agreed to in writing, software 
    * distributed under the License is distributed on an "AS IS" BASIS, 
    * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
    * See the License for the specific language governing permissions and 
    * limitations under the License. 
    */ 
    static public void decodeYUV420SP(int[] rgb, byte[] yuv420sp, int width, int height) 
    { 
     final int frameSize = width * height; 

     for (int j = 0, yp = 0; j < height; j++) { 
      int uvp = frameSize + (j >> 1) * width, u = 0, v = 0; 
      for (int i = 0; i < width; i++, yp++) { 
       int y = (0xff & ((int) yuv420sp[yp])) - 16; 
       if (y < 0) y = 0; 
       if ((i & 1) == 0) { 
        v = (0xff & yuv420sp[uvp++]) - 128; 
        u = (0xff & yuv420sp[uvp++]) - 128; 
       } 

       int y1192 = 1192 * y; 
       int r = (y1192 + 1634 * v); 
       int g = (y1192 - 833 * v - 400 * u); 
       int b = (y1192 + 2066 * u); 

       if (r < 0) r = 0; else if (r > 262143) r = 262143; 
       if (g < 0) g = 0; else if (g > 262143) g = 262143; 
       if (b < 0) b = 0; else if (b > 262143) b = 262143; 

       rgb[yp] = 0xff000000 | ((r << 6) & 0xff0000) | ((g >> 2) & 0xff00) | ((b >> 10) & 0xff); 
      } 
     } 
    } 

    // Preview callback used whenever new frame is available...send image via UDP !!! 
    private class cam_PreviewCallback implements PreviewCallback 
    { 
     @Override 
     public void onPreviewFrame(byte[] data, Camera camera) 
     { 
      if(STOP_THREAD == true) 
      { 
       mCamera.setPreviewCallback(null); 
       mCamera.stopPreview(); 
       mCamera.release(); 
       mCamera = null; 
       return; 
      } 

      if (mBitmap == null)  //create Bitmap image first time 
      { 
       Camera.Parameters params = camera.getParameters(); 
       width_ima = params.getPreviewSize().width; 
       height_ima = params.getPreviewSize().height;      
       mBitmap = Bitmap.createBitmap(width_ima, height_ima, Bitmap.Config.RGB_565); 
       mRGBData = new int[width_ima * height_ima]; 
      } 

      decodeYUV420SP(mRGBData, data, width_ima, height_ima); 
      mBitmap.setPixels(mRGBData, 0, width_ima, 0, 0, width_ima, height_ima); 

      send_data_UDP(); 
     } 
    } 

} 

매니페스트

package carl.IOIO_car; 

import android.hardware.SensorManager; 
import android.util.Log; 
import android.view.SurfaceHolder; 
import android.view.SurfaceView; 

public class Main_thread extends Thread 
{ 
    SurfaceView parent_context; 
    SensorManager mSensorManager = null; 
    Cam_thread the_cam; 
    Sensors_thread the_sensors; 
    IOIO_Thread ioio_thread_; 
    String ip_address; 
    Android_Activity the_app; 

    public Main_thread(Android_Activity app, SurfaceView v, SensorManager m, String ip) 
    { 
     super(); 

     parent_context = v;  
     mSensorManager = m; 
     ip_address = ip; 
     the_app = app; 
     Log.e("Debug Main", "IP is " + ip_address); 
     the_cam = new Cam_thread(parent_context,ip_address); 
     the_sensors = new Sensors_thread(mSensorManager,ip_address); 
     ioio_thread_ = new IOIO_Thread(the_app, ip_address); 
    } 

    public void run() 
    {    
     //ioio_thread_.start(); 
     the_cam.start_thread(); 


    } 

    public void stop_simu() 
    { 
     the_cam.stop_thread(); 
     the_sensors.stop_thread(); 
     //ioio_thread_.abort(); 
    } 
} 

Cam_Thread이 원래 코드 박사 오로에 의해 작성되었습니다. http://www.cogsci.uci.edu/~noros/android_car.html

Answer 1

모든 카메라 물건과 물건은 예를 들어 OnCreate 등의 활동에서 만들어야합니다. 사진 촬영 신호는 다른 상황에서 푸시 될 수 있습니다.

Answer 2

그렇지 않습니다. Handler로 작은 지연을 설정하면 Nexus에서도 제대로 작동합니다.

그냥 그 장치에 검은 그림과 함께 문제를 자신했지만, 지연 모든 것을 1 초에

Answer 3

05-22이 11 일 : 27 : 24.977 16750-16750가/com.egomez.facedetection I/CameraActivity를 : 27 : 25.219 16750-16750/com.egomez.facedetection의 D/카메라 : 카메라 11월 5일부터 22일까지 전환 응용 프로그램이

내가 서피스 뷰 SurfaceView의 홀더를 얻어야했다 그 오류를 제거하려면 NULL 표면을 통과합니다 (에 시나리오는 내가 수정하려고 시도했다 전면 카메라에서 뒤쪽 카메라와 viceversa로 전환).

public void switchCamera(){ 
    Log.i(TAG, "Switching Camera"); 
    if (mCamera != null) { 
     mCamera.stopPreview(); 
     mCamera.release(); 
     //mCamera = null; 
    } 

    //swap the id of the camera to be used 
    if (camId == Camera.CameraInfo.CAMERA_FACING_BACK) { 
     camId = Camera.CameraInfo.CAMERA_FACING_FRONT; 
    }else { 
     camId = Camera.CameraInfo.CAMERA_FACING_BACK; 
    } 
    try { 
     mCamera = Camera.open(camId); 
     //mCamera.setDisplayOrientation(90); 
     //You must get the holder of SurfaceView!!! 
     mCamera.setPreviewDisplay(mView.getHolder()); 
     //Then resume preview... 
     mCamera.startPreview(); 
    } 
    catch (Exception e) { e.printStackTrace(); } 
} 

비슷한 문제가있는 사람이면 누구나 도움이 될 수 있기를 바랍니다.