问题
Hi i want to show a live camera preview side by side on my Android Phone. Like this:
https://lh6.googleusercontent.com/-Ngo4tD4AvWY/U8JOHxxQ9KI/AAAAAAAACK8/NZjnw1Yqg8A/w384-h287/2.jpg
It works if just the left half screen shows the live preview or just the right side, but if i want to show the left and the rigth side simultaneously i just get a black screen And i dont know why.
Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="de.test.normaltest.sbscameraview" >
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:screenOrientation="landscape">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
MainActivity
public class MainActivity extends Activity {
private CameraView cameraView1;
private CameraView cameraView2;
private Camera mCamera1;
private Camera mCamera2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mCamera1 = getCameraInstance();
cameraView1 = new CameraView(this, mCamera1);
cameraView2 = new CameraView(this, mCamera1);
FrameLayout preview1 = (FrameLayout) findViewById(R.id.camera_preview1);
preview1.addView(cameraView1);
FrameLayout preview2 = (FrameLayout) findViewById(R.id.camera_preview2);
preview2.addView(cameraView2);
}
/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance(){
Camera c = null;
try {
c = Camera.open(); // attempt to get a Camera instance
}
catch (Exception e){
Log.i("camera", "null");
}
return c; // returns null if camera is unavailable
}
}
CameraView
public class CameraView extends SurfaceView implements SurfaceHolder.Callback {
private SurfaceHolder mHolder;
private Camera mCamera;
public CameraView(Context context, Camera camera) {
super(context);
mHolder = getHolder();
mHolder.addCallback(this);
mCamera = camera;
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
mCamera.setPreviewDisplay(holder);
mCamera.startPreview();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
Log.i("CameraView", "surfaceChanged");
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
}
回答1:
You can use these codes to open camera on Google Cardboard.
Manifest:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.oculab.mehmettaha.vrcamera" >
<uses-permission android:name="android.permission.NFC" />
<uses-permission android:name="android.permission.VIBRATE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" android:required="false" />
<uses-feature android:name="android.hardware.camera.autofocus" android:required="false" />
<uses-feature android:name="android.hardware.camera.front" android:required="false" />
<uses-feature android:glEsVersion="0x00020000" android:required="true" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:screenOrientation="landscape"
android:configChanges="orientation|keyboardHidden|screenSize">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
CardboardOverlayView.java
public class CardboardOverlayView extends LinearLayout {
private static final String TAG = CardboardOverlayView.class.getSimpleName();
private final CardboardOverlayEyeView mLeftView;
private final CardboardOverlayEyeView mRightView;
private AlphaAnimation mTextFadeAnimation;
public CardboardOverlayView(Context context, AttributeSet attrs) {
super(context, attrs);
setOrientation(HORIZONTAL);
LayoutParams params = new LayoutParams(
LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT, 1.0f);
params.setMargins(0, 0, 0, 0);
mLeftView = new CardboardOverlayEyeView(context, attrs);
mLeftView.setLayoutParams(params);
addView(mLeftView);
mRightView = new CardboardOverlayEyeView(context, attrs);
mRightView.setLayoutParams(params);
addView(mRightView);
// Set some reasonable defaults.
setDepthOffset(0.016f);
setColor(Color.rgb(150, 255, 180));
setVisibility(View.VISIBLE);
mTextFadeAnimation = new AlphaAnimation(1.0f, 0.0f);
mTextFadeAnimation.setDuration(5000);
}
public void show3DToast(String message) {
setText(message);
setTextAlpha(1f);
mTextFadeAnimation.setAnimationListener(new EndAnimationListener() {
@Override
public void onAnimationEnd(Animation animation) {
setTextAlpha(0f);
}
});
startAnimation(mTextFadeAnimation);
}
private abstract class EndAnimationListener implements Animation.AnimationListener {
@Override public void onAnimationRepeat(Animation animation) {}
@Override public void onAnimationStart(Animation animation) {}
}
private void setDepthOffset(float offset) {
mLeftView.setOffset(offset);
mRightView.setOffset(-offset);
}
private void setText(String text) {
mLeftView.setText(text);
mRightView.setText(text);
}
private void setTextAlpha(float alpha) {
mLeftView.setTextViewAlpha(alpha);
mRightView.setTextViewAlpha(alpha);
}
private void setColor(int color) {
mLeftView.setColor(color);
mRightView.setColor(color);
}
/**
* A simple view group containing some horizontally centered text underneath a horizontally
* centered image.
*
* This is a helper class for CardboardOverlayView.
*/
private class CardboardOverlayEyeView extends ViewGroup {
private final ImageView imageView;
private final TextView textView;
private float offset;
public CardboardOverlayEyeView(Context context, AttributeSet attrs) {
super(context, attrs);
imageView = new ImageView(context, attrs);
imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
imageView.setAdjustViewBounds(true); // Preserve aspect ratio.
addView(imageView);
textView = new TextView(context, attrs);
textView.setTextSize(TypedValue.COMPLEX_UNIT_DIP, 14.0f);
textView.setTypeface(textView.getTypeface(), Typeface.BOLD);
textView.setGravity(Gravity.CENTER);
textView.setShadowLayer(3.0f, 0.0f, 0.0f, Color.DKGRAY);
addView(textView);
}
public void setColor(int color) {
imageView.setColorFilter(color);
textView.setTextColor(color);
}
public void setText(String text) {
textView.setText(text);
}
public void setTextViewAlpha(float alpha) {
textView.setAlpha(alpha);
}
public void setOffset(float offset) {
this.offset = offset;
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
// Width and height of this ViewGroup.
final int width = right - left;
final int height = bottom - top;
// The size of the image, given as a fraction of the dimension as a ViewGroup. We multiply
// both width and heading with this number to compute the image's bounding box. Inside the
// box, the image is the horizontally and vertically centered.
final float imageSize = 0.12f;
// The fraction of this ViewGroup's height by which we shift the image off the ViewGroup's
// center. Positive values shift downwards, negative values shift upwards.
final float verticalImageOffset = -0.07f;
// Vertical position of the text, specified in fractions of this ViewGroup's height.
final float verticalTextPos = 0.52f;
// Layout ImageView
float imageMargin = (1.0f - imageSize) / 2.0f;
float leftMargin = (int) (width * (imageMargin + offset));
float topMargin = (int) (height * (imageMargin + verticalImageOffset));
imageView.layout(
(int) leftMargin, (int) topMargin,
(int) (leftMargin + width * imageSize), (int) (topMargin + height * imageSize));
// Layout TextView
leftMargin = offset * width;
topMargin = height * verticalTextPos;
textView.layout(
(int) leftMargin, (int) topMargin,
(int) (leftMargin + width), (int) (topMargin + height * (1.0f - verticalTextPos)));
}
}
}
MainActivity.java
public class MainActivity extends CardboardActivity implements CardboardView.StereoRenderer, OnFrameAvailableListener {
private static final String TAG = "VRCamMtMMainAc";
private static final int GL_TEXTURE_EXTERNAL_OES = 0x8D65;
private Camera camera;
private final String vertexShaderCode =
"attribute vec4 position;" +
"attribute vec2 inputTextureCoordinate;" +
"varying vec2 textureCoordinate;" +
"void main()" +
"{" +
"gl_Position = position;" +
"textureCoordinate = inputTextureCoordinate;" +
"}";
private final String fragmentShaderCode =
"#extension GL_OES_EGL_image_external : require\n" +
"precision mediump float;" +
"varying vec2 textureCoordinate; \n" +
"uniform samplerExternalOES s_texture; \n" +
"void main(void) {" +
" gl_FragColor = texture2D( s_texture, textureCoordinate );\n" +
//" gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);\n" +
"}";
private FloatBuffer vertexBuffer, textureVerticesBuffer, vertexBuffer2;
private ShortBuffer drawListBuffer, buf2;
private int mProgram;
private int mPositionHandle, mPositionHandle2;
private int mColorHandle;
private int mTextureCoordHandle;
// number of coordinates per vertex in this array
static final int COORDS_PER_VERTEX = 2;
static float squareVertices[] = { // in counterclockwise order:
-1.0f, -1.0f, // 0.left - mid
1.0f, -1.0f, // 1. right - mid
-1.0f, 1.0f, // 2. left - top
1.0f, 1.0f, // 3. right - top
};
private short drawOrder[] = {0, 2, 1, 1, 2, 3}; // order to draw vertices
private short drawOrder2[] = {2, 0, 3, 3, 0, 1}; // order to draw vertices
static float textureVertices[] = {
0.0f, 1.0f, // A. left-bottom
1.0f, 1.0f, // B. right-bottom
0.0f, 0.0f, // C. left-top
1.0f, 0.0f // D. right-top
};
private final int vertexStride = COORDS_PER_VERTEX * 4; // 4 bytes per vertex
private ByteBuffer indexBuffer; // Buffer for index-array
private int texture;
private CardboardOverlayView mOverlayView;
private CardboardView cardboardView;
private SurfaceTexture surface;
private float[] mView;
private float[] mCamera;
public void startCamera(int texture) {
surface = new SurfaceTexture(texture);
surface.setOnFrameAvailableListener(this);
camera = Camera.open();
Camera.Parameters params = camera.getParameters();
params.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO);
// Check what resolutions are supported by your camera
/*List<Camera.Size> sizes = params.getSupportedPictureSizes();
// Iterate through all available resolutions and choose one.
// The chosen resolution will be stored in mSize.
Camera.Size mSize = null;
for (Camera.Size size : sizes) {
Log.i(TAG, "Available resolution: " + size.width + "x" + size.height);
mSize = size;
}
params.setPictureSize(5312,2988);*/
camera.setParameters(params);
try {
camera.setPreviewTexture(surface);
camera.startPreview();
} catch (IOException ioe)
{
Log.i(TAG, "CAM LAUNCH FAILED");
}
}
static private int createTexture() {
int[] texture = new int[1];
GLES20.glGenTextures(1, texture, 0);
GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, texture[0]);
GLES20.glTexParameterf(GL_TEXTURE_EXTERNAL_OES,
GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_LINEAR);
GLES20.glTexParameterf(GL_TEXTURE_EXTERNAL_OES,
GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES,
GL10.GL_TEXTURE_WRAP_S, GL10.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES,
GL10.GL_TEXTURE_WRAP_T, GL10.GL_CLAMP_TO_EDGE);
return texture[0];
}
private int loadGLShader(int type, String code) {
int shader = GLES20.glCreateShader(type);
GLES20.glShaderSource(shader, code);
GLES20.glCompileShader(shader);
// Get the compilation status.
final int[] compileStatus = new int[1];
GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compileStatus, 0);
// If the compilation failed, delete the shader.
if (compileStatus[0] == 0) {
Log.e(TAG, "Error compiling shader: " + GLES20.glGetShaderInfoLog(shader));
GLES20.glDeleteShader(shader);
shader = 0;
}
if (shader == 0) {
throw new RuntimeException("Error creating shader.");
}
return shader;
}
/**
* Checks if we've had an error inside of OpenGL ES, and if so what that error is.
*
* @param func
*/
private static void checkGLError(String func) {
int error;
while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
Log.e(TAG, func + ": glError " + error);
throw new RuntimeException(func + ": glError " + error);
}
}
/**
* Sets the view to our CardboardView and initializes the transformation matrices we will use
* to render our scene.
*
* @param savedInstanceState
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cardboardView = (CardboardView) findViewById(R.id.cardboard_view);
cardboardView.setRenderer(this);
setCardboardView(cardboardView);
mCamera = new float[16];
mView = new float[16];
mOverlayView = (CardboardOverlayView) findViewById(R.id.overlay);
//mOverlayView.show3DToast("Pull the magnet when you find an object.");
}
@Override
public void onRendererShutdown() {
Log.i(TAG, "onRendererShutdown");
}
@Override
public void onSurfaceChanged(int width, int height) {
Log.i(TAG, "onSurfaceChanged");
}
/**
* Creates the buffers we use to store information about the 3D world. OpenGL doesn't use Java
* arrays, but rather needs data in a format it can understand. Hence we use ByteBuffers.
*
* @param config The EGL configuration used when creating the surface.
*/
@Override
public void onSurfaceCreated(EGLConfig config) {
Log.i(TAG, "onSurfaceCreated");
GLES20.glClearColor(0.1f, 0.1f, 0.1f, 0.5f); // Dark background so text shows up well
ByteBuffer bb = ByteBuffer.allocateDirect(squareVertices.length * 4);
bb.order(ByteOrder.nativeOrder());
vertexBuffer = bb.asFloatBuffer();
vertexBuffer.put(squareVertices);
vertexBuffer.position(0);
ByteBuffer dlb = ByteBuffer.allocateDirect(drawOrder.length * 2);
dlb.order(ByteOrder.nativeOrder());
drawListBuffer = dlb.asShortBuffer();
drawListBuffer.put(drawOrder);
drawListBuffer.position(0);
ByteBuffer bb2 = ByteBuffer.allocateDirect(textureVertices.length * 4);
bb2.order(ByteOrder.nativeOrder());
textureVerticesBuffer = bb2.asFloatBuffer();
textureVerticesBuffer.put(textureVertices);
textureVerticesBuffer.position(0);
int vertexShader = loadGLShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
int fragmentShader = loadGLShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);
mProgram = GLES20.glCreateProgram(); // create empty OpenGL ES Program
GLES20.glAttachShader(mProgram, vertexShader); // add the vertex shader to program
GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program
GLES20.glLinkProgram(mProgram);
texture = createTexture();
startCamera(texture);
}
/**
* Prepares OpenGL ES before we draw a frame.
*
* @param headTransform The head transformation in the new frame.
*/
@Override
public void onNewFrame(HeadTransform headTransform) {
float[] mtx = new float[16];
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
surface.updateTexImage();
surface.getTransformMatrix(mtx);
}
@Override
public void onFrameAvailable(SurfaceTexture arg0) {
this.cardboardView.requestRender();
}
/**
* Draws a frame for an eye. The transformation for that eye (from the camera) is passed in as
* a parameter.
*
* @param transform The transformations to apply to render this eye.
*/
@Override
public void onDrawEye(EyeTransform transform) {
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
GLES20.glUseProgram(mProgram);
GLES20.glActiveTexture(GL_TEXTURE_EXTERNAL_OES);
GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, texture);
mPositionHandle = GLES20.glGetAttribLocation(mProgram, "position");
GLES20.glEnableVertexAttribArray(mPositionHandle);
GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT,
false, vertexStride, vertexBuffer);
mTextureCoordHandle = GLES20.glGetAttribLocation(mProgram, "inputTextureCoordinate");
GLES20.glEnableVertexAttribArray(mTextureCoordHandle);
GLES20.glVertexAttribPointer(mTextureCoordHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT,
false, vertexStride, textureVerticesBuffer);
mColorHandle = GLES20.glGetAttribLocation(mProgram, "s_texture");
GLES20.glDrawElements(GLES20.GL_TRIANGLES, drawOrder.length,
GLES20.GL_UNSIGNED_SHORT, drawListBuffer);
// Disable vertex array
GLES20.glDisableVertexAttribArray(mPositionHandle);
GLES20.glDisableVertexAttribArray(mTextureCoordHandle);
Matrix.multiplyMM(mView, 0, transform.getEyeView(), 0, mCamera, 0);
}
@Override
public void onFinishFrame(Viewport viewport) {
}
@Override
public void onCardboardTrigger() {
}
}
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/ui_layout"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<com.google.vrtoolkit.cardboard.CardboardView
android:id="@+id/cardboard_view"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true" />
<com.oculab.mehmettaha.vrcamera.CardboardOverlayView
android:id="@+id/overlay"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" />
</RelativeLayout>
Don' t forget the importing libraries such as cardboard.jar and libprotobuf-java-...jar
Finally, you should get the result like this:
Cheers!
来源：https://stackoverflow.com/questions/27881389/android-side-by-side-camera