Android摄像头 - 应用程序通过空面 [英] Android Camera - app passed NULL surface
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问题描述
每当我跑我得到错误的cam_thread应用程序通过空面。这code理应适用于HTC的不可思议1.我已经重新配置稍微要在Droid X的运行。不过，我仍然得到这个错误。
公共类Android_Activity扩展活动
{
Main_thread模拟器;
切换按钮切换按钮;
的EditText ip_text;
的SensorManager SM = NULL;
SurfaceView视图;
Sensors_thread the_sensors = NULL;
字符串IP_地址;
Android_Activity the_app;
@覆盖
保护无效的onCreate（包savedInstanceState）
{
super.onCreate（savedInstanceState）;
的setContentView（R.layout.main）;
鉴于=新SurfaceView（本）;
SM =（的SensorManager）getSystemService（SENSOR_SERVICE）;
ip_text =（EditText上）findViewById（R.id.IP_edit_txt）;
切换按钮=（切换按钮）findViewById（R.id.CameraButton）;
togglebutton.setOnClickListener（新btn_listener（））;
the_app =这一点;
}
@覆盖
保护无效onResume（）
{
super.onResume（）;
}
保护无效的onStop（）
{
super.onStop（）;
simulator.stop_simu（）;
this.finish（）;
}
私有类btn_listener实现OnClickListener
{
公共无效的onClick（视图v）
{
//执行的点击操作
如果（togglebutton.isChecked（））
{
IP_地址= ip_text.getText（）的toString（）。
仿真=新Main_thread（the_app，查看，SM，IP_地址）;
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，开始流+ IP_地址，Toast.LENGTH_SHORT）.show（）;
} 其他
{
simulator.stop_simu（）;
sm.unregisterListener（the_sensors）;
Toast.makeText（Android_Activity.this，停止流，Toast.LENGTH_SHORT）.show（）;
}
}
}
}
主线
包carl.IOIO_car;
进口android.hardware.SensorManager;
进口android.util.Log;
进口android.view.SurfaceHolder;
进口android.view.SurfaceView;
公共类Main_thread继承Thread
{
SurfaceView parent_context;
的SensorManager mSensorManager = NULL;
Cam_thread the_cam;
Sensors_thread the_sensors;
IOIO_Thread ioio_thread_;
字符串IP_ADDRESS;
Android_Activity the_app;
公共Main_thread（Android_Activity应用程序，SurfaceView V，的SensorManager男，串IP）
{
超（）;
v parent_context =;
mSensorManager =米;
IP_ADDRESS = IP;
the_app =应用;
Log.e（调试主，IP是+ IP_ADDRESS）;
the_cam =新Cam_thread（parent_context，IP_ADDRESS）;
the_sensors =新Sensors_thread（mSensorManager，IP_ADDRESS）;
ioio_thread_ =新IOIO_Thread（the_app，IP_ADDRESS）;
}
公共无效的run（）
{
//ioio_thread_.start（）;
the_cam.start_thread（）;
}
公共无效stop_simu（）
{
the_cam.stop_thread（）;
the_sensors.stop_thread（）;
//ioio_thread_.abort（）;
}
}
Cam_Thread
包carl.IOIO_car;
进口java.io.ByteArrayOutputStream中;
进口java.net.DatagramPacket中;
进口java.net.DatagramSocket中;
进口的java.net.InetAddress;
进口的java.util.List;
进口android.graphics.Bitmap;
进口android.hardware.Camera;
进口android.hardware.Camera previewCallback。
进口android.util.Log;
进口android.view.SurfaceView;
公共类Cam_thread
{
相机mCamera;
公共静态INT HEADER_SIZE = 5;
公共静态INT DATAGRAM_MAX_SIZE = 1450 - HEADER_SIZE;
INT frame_nb = 0;
INT size_packet_sent = 0;
InetAddress类serverAddr;
DatagramSocket的插座;
位图mBitmap;
INT [] mRGBData;
INT width_ima，height_ima;
私有静态最后字符串变量=IP_cam;
SurfaceView parent_context;
私人布尔STOP_THREAD;
字符串IP_ADDRESS;
公共Cam_thread（SurfaceView背景下，字符串IP）
{
parent_context =背景;
IP_ADDRESS = IP;
}
私人无效的init（）
{
尝试
{
serverAddr = InetAddress.getByName（IP地址）;
插座=新的DatagramSocket（）;
如果（mCamera！= NULL）{
Log.e（TAG，归零相机）;
mCamera.stop preVIEW（）;
mCamera.set previewCallback（空）;
mCamera.release（）;
mCamera = NULL;
}
如果（mCamera == NULL）{
mCamera = Camera.open（）;
Log.e（TAG，设置摄像头）;
Camera.Parameters参数= mCamera.getParameters（）;
//获取支持preVIEW尺寸的列表，并分配一个
名单＆LT; Camera.Size＆GT; previewSizes = parameters.getSupported previewSizes（）;
Camera.Size previewSize = previewSizes.get（0）;
parameters.set previewSize（previewSize.width，previewSize.height）;
//设置帧速率
parameters.set previewFrameRate（30）;
//设置场景
名单＆LT;字符串＆GT;模式= parameters.getSupportedSceneModes（）;
parameters.setSceneMode（modes.get（0））;
//设置对焦模式
名单＆LT;字符串＆GT;聚焦= parameters.getSupportedFocusModes（）;
parameters.setFocusMode（focus.get（0））;
//应用参数，相机对象
mCamera.setParameters（参数）;
//提供一个表面
如果（parent_context.getHolder（）== NULL）
Log.e（TAG，它是一种空持有人）;
Log.e（调试，之前）;
mCamera.set previewDisplay（parent_context.getHolder（））;
Log.e（调试，后）;
//设置呼叫时preVIEW数据可用
mCamera.set previewCallback（新cam_ previewCallback（））;
Log.e（TAG，摄像机配置）;
//启动preVIEW
Log.e（TAG，启动preVIEW）;
mCamera.start preVIEW（）;
/ *
parameters.set previewSize（320，240）;
parameters.set previewFrameRate（30）;
parameters.setSceneMode（Camera.Parameters.SCENE_MODE_SPORTS）;
parameters.setFocusMode（Camera.Parameters.FOCUS_MODE_AUTO）;
parameters.setColorEffect（Camera.Parameters.EFFECT_NONE）;
mCamera.setParameters（参数）;
mCamera.set previewDisplay（parent_context.getHolder（））;
mCamera.set previewCallback（新cam_ previewCallback（））;
Log.e（TAG，启动preVIEW）;
mCamera.start preVIEW（）;
* /
}
}
赶上（例外的例外）
{
Log.e（TAG，错误，除外）;
}
}
公共无效start_thread（）
{
Log.e（凸轮，开始的凸轮线）;
在里面（）;
}
公共无效stop_thread（）
{
STOP_THREAD = TRUE;
如果（mCamera！= NULL）{
mCamera.stop preVIEW（）;
mCamera.release（）;
mCamera = NULL;
}
socket.close（）;
}
公共无效send_data_UDP（）
{
Log.e（TAG，开始向凸轮数据）;
如果（mBitmap！= NULL）
{
INT size_p = 0，I;
ByteArrayOutputStream字节流=新ByteArrayOutputStream（）;
mBitmap.com preSS（Bitmap.Com pressFormat.JPEG，50字节流）; // !!!!!!!改变COM pression率改变数据包大小
字节数据[] = byteStream.toByteArray（）;
Log.e（TAG，SIZE：+ data.length）;
INT nb_packets =（int）的Math.ceil（data.length /（浮点）DATAGRAM_MAX_SIZE）;
INT大小= DATAGRAM_MAX_SIZE;
/ *通过切片循环* /
对于（i = 0; I＆LT; nb_packets;我++）
{
如果（ⅰ大于0＆安培;＆安培;我== nb_packets-1）大小= data.length - I * DATAGRAM_MAX_SIZE;
/ *设置附加的头* /
byte []的数据2 =新的字节[HEADER_SIZE +大小]
data2的[0] =（字节）frame_nb;
数据2 [1] =（字节）nb_packets;
数据2 [2] =（字节）I;
数据2 [3] =（字节）（大小＆GT;→8）;
数据2 [4] =（字节）的大小;
/ *当前片复制到字节数组* /
System.arraycopy（数据，I * DATAGRAM_MAX_SIZE，数据2，HEADER_SIZE，大小）;
尝试
{
size_p = data2.length;
DatagramPacket类包=新的DatagramPacket（数据2，size_p，serverAddr，9000）;
socket.send（包）;
Log.e（TAG，已发送凸轮框！）;
}赶上（例外五）{Log.e（TAG，错误，E）;}
}
frame_nb ++;
如果（frame_nb == 128）frame_nb = 0;
}
}
/ *功能转换图像RGB格式的项目采取：ViewfinderEE368
* http://www.stanford.edu/class/ee368/Android/ViewfinderEE368/
*
*版权所有（C）2007年Android开源项目
*
* Apache许可证下授权，版本2.0（以下简称许可证）;
*您可能不能使用这个文件除了在遵守许可。
*您可以在获得许可证的副本
*
* http://www.apache.org/licenses/LICENSE-2.0
*
*除非适用法律要求或书面同意，软件
*许可证下发布分布在原样的基础上，
*无担保或任何形式的条件，无论是EX preSS或暗示的保证。
*请参阅许可的特定语言的管理权限和
*许可下限制。
* /
静态公共无效去codeYUV420SP（INT [] RGB，byte []的yuv420sp，诠释的宽度，高度INT）
{
最终诠释框架尺寸=宽*高;
对于（INT J = 0，YP = 0; J＆LT;高度; J ++）{
INT UVP =框架尺寸+（J＆GT;→1）*宽度，U = 0，V = 0;
的for（int i = 0; I＆LT;宽度;我++，YP ++）{
INT Y =（0xFF的及（（int）的yuv420sp [YP]）） - 16;
如果（γ℃的）Y = 0;
如果（（ⅰ＆安培; 1）== 0）{
V =（0xFF的＆放大器; yuv420sp [UVP ++]） - 128;
U =（0xFF的＆放大器; yuv420sp [UVP ++]） - 128;
}
INT y1192 = 1192 * Y;
INT R =（y1192 + 1634 * V）;
INT G =（y1192 - 833 * V - 400 * U）;
INT B =（y1192 + 2066 * U）;
如果（为r 0）R = 0;否则，如果（R＆GT; 262143）R = 262143;
如果（克℃，）克= 0;否则，如果（G＆GT; 262143）G = 262143;
如果（b将0）B = 0;否则，如果（B＆GT; 262143）B = 262143;
RGB [YP] = 0xff000000 | （（为r＆10 6）及为0xFF0000）| （（g取代;→2）及为0xFF00）| （（B个大于10）及0xff的）;
}
}
}
// preVIEW回调时使用新帧可...通过UDP发送的图像！
私有类cam_ previewCallback实现previewCallback
{
@覆盖
在previewFrame公共无效（byte []的数据，摄像头摄像头）
{
如果（STOP_THREAD ==真）
{
mCamera.set previewCallback（空）;
mCamera.stop preVIEW（）;
mCamera.release（）;
mCamera = NULL;
返回;
}
如果（mBitmap == NULL）//创建位图图像第一次
{
Camera.Parameters PARAMS = camera.getParameters（）;
width_ima = params.get previewSize（）宽。
height_ima = params.get previewSize（）的高度。
mBitmap = Bitmap.createBitmap（width_ima，height_ima，Bitmap.Config.RGB_565）;
mRGBData =新INT [width_ima * height_ima]。
}
德codeYUV420SP（mRGBData，数据，width_ima，height_ima）;
mBitmap.setPixels（mRGBData，0，width_ima，0，0，width_ima，height_ima）;
send_data_UDP（）;
}
}
}
清单
＆LT; XML版本=1.0编码=UTF-8＆GT？;
＆LT;舱单的xmlns：机器人=http://schemas.android.com/apk/res/android
包=carl.IOIO_car
安卓版code =1
机器人：VERSIONNAME =1.0＆GT;
＆LT;使用-SDK安卓的minSdkVersion =8/＆GT;
＆lt;应用机器人：图标=@可绘制/图标机器人：可调试=真正的机器人：标签=@字符串/ APP_NAME＆GT;
＆LT;活动机器人：名称=carl.IOIO_car.Android_Activity
机器人：标签=@字符串/ APP_NAME
机器人：主题=@安卓风格/ Theme.NoTitleBar.Fullscreen
机器人：screenOrientation =景观与GT;
＆LT;意向滤光器＆gt;
＆lt;作用机器人：名称=android.intent.action.MAIN/＆GT;
＆LT;类机器人：名称=android.intent.category.LAUNCHER/＆GT;
＆所述; /意图滤光器＆gt;
＆LT; /活性GT;
＆LT; /用途＆gt;
＆LT;使用-权限的Android：名称=android.permission.CAMERA/＆GT;
＆LT;使用-权限的Android：名称=android.permission.ACCESS_NETWORK_STATE/＆GT;
＆LT;使用-权限的Android：名称=android.permission.INTERNET对/＆GT;
＆LT;使用-权限的Android：名称=android.permission.WAKE_LOCK/＆GT;
＆LT;使用-权限的Android：名称=android.permission.ACCESS_WIFI_STATE＆GT;＆LT; /使用-许可＆GT;
＆LT;使用-权限的Android：名称=android.permission.UPDATE_DEVICE_STATS＆GT;＆LT; /使用-许可＆GT;
＆LT;使用-权限的Android：名称=android.permission.CHANGE_WIFI_STATE＆GT;＆LT; /使用-许可＆GT;
＆LT;使用-权限的Android：名称=android.permission.CHANGE_WIFI_MULTICAST_STATE＆GT;＆LT; /使用-许可＆GT;
＆LT;使用-权限的Android：名称=android.permission.WRITE_EXTERNAL_STORAGE/＆GT;
＆LT;使用特征的android：NAME =android.hardware.camera/＆GT;
＆LT;使用特征的android：NAME =android.hardware.camera.autofocus/＆GT;
＆LT; /舱单＆GT;
这原来code是由Oros的博士。 <一href="http://www.cogsci.uci.edu/~noros/android_car.html">http://www.cogsci.uci.edu/~noros/android_car.html
解决方案
11月5日至22号：27：24.977 16750-16750 / com.egomez.facedetection I / CameraActivity：切换摄像头 11月5号至22日：27：25.219 16750-16750 / com.egomez.facedetection D /摄像头：应用程序通过空面
要摆脱这个错误我得SurfaceView持有人（对我试图解决从前置摄像头被切换到相机背面，反之亦然场景）的。
公共无效switchCamera（）{
Log.i（TAG，切换相机）;
如果（mCamera！= NULL）{
mCamera.stop preVIEW（）;
mCamera.release（）;
// mCamera = NULL;
}
//交换所使用的照相机的id
如果（CAMID == Camera.CameraInfo.CAMERA_FACING_BACK）{
CAMID = Camera.CameraInfo.CAMERA_FACING_FRONT;
}其他 {
CAMID = Camera.CameraInfo.CAMERA_FACING_BACK;
}
尝试 {
mCamera = Camera.open（CAMID）;
//mCamera.setDisplayOrientation(90）;
//你必须得到SurfaceView的持有人！
mCamera.set previewDisplay（mView.getHolder（））;
//然后恢复preVIEW ...
mCamera.start preVIEW（）;
}
赶上（例外五）{e.printStackTrace（）; }
}
希望它可以帮助任何人遇到了类似的问题。
Whenever I run the cam_thread I get the error "app passed NULL surface". This code supposedly works on the HTC Incredible 1. I've reconfigured it slightly to run on a droid x. However I still get this error.
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();
}
}
}
}
Main Thread
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_Thread
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();
}
}
}
Manifest
<?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>
This original code was written by Dr. Oros. http://www.cogsci.uci.edu/~noros/android_car.html
解决方案
05-22 11:27:24.977 16750-16750/com.egomez.facedetection I/CameraActivity﹕ Switching Camera 05-22 11:27:25.219 16750-16750/com.egomez.facedetection D/Camera﹕ app passed NULL surface
To get rid of that error I had to get holder of SurfaceView (on the scenario I was attempting to fix was Switching from front camera to back camera and viceversa).
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(); }
}
Hope it helps for anyone running into similar issue.
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