La caméra androïde ne fonctionnera pas. startPreview échoue

J'obtiens ces erreurs de LogCat:

10-30 00:31:51.494: D/CameraHal(1205): CameraHal setOverlay/1/00000000/00000000
10-30 00:31:51.494: E/CameraHal(1205): Trying to set overlay, but overlay is null!, line:3472
10-30 00:31:51.494: W/CameraService(1205): Overlay create failed - retrying
...
10-30 00:31:52.526: E/CameraService(1205): Overlay Creation Failed!
...
10-30 00:31:52.588: E/AndroidRuntime(5040): FATAL EXCEPTION: main
10-30 00:31:52.588: E/AndroidRuntime(5040): java.lang.RuntimeException: startPreview failed
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.hardware.Camera.startPreview(Native Method)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at com.matthewmitchell.nightcam.CameraSurfaceView.surfaceCreated(CameraSurfaceView.java:47)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.SurfaceView.updateWindow(SurfaceView.java:544)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.SurfaceView.dispatchDraw(SurfaceView.java:341)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewGroup.drawChild(ViewGroup.java:1638)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.View.draw(View.java:6743)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.widget.FrameLayout.draw(FrameLayout.java:352)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewGroup.drawChild(ViewGroup.java:1640)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewGroup.drawChild(ViewGroup.java:1638)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.View.draw(View.java:6743)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.widget.FrameLayout.draw(FrameLayout.java:352)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1876)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewRoot.draw(ViewRoot.java:1407)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewRoot.performTraversals(ViewRoot.java:1163)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1727)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.os.Looper.loop(Looper.java:123)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at android.app.ActivityThread.main(ActivityThread.java:4627)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at java.lang.reflect.Method.invokeNative(Native Method)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at java.lang.reflect.Method.invoke(Method.java:521)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
10-30 00:31:52.588: E/AndroidRuntime(5040):     at dalvik.system.NativeStart.main(Native Method)

Voici la classe d'activité:

public class NightCamActivity extends Activity {
    private GLSurfaceView mGLView;
    CameraSurfaceView surface_view;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Create a GLSurfaceView instance and set it
        // as the ContentView for this Activity
        Debug.out("Welcome");
        surface_view = new CameraSurfaceView(this);
        mGLView = new MySurfaceView(this);
        setContentView(mGLView);
        addContentView(surface_view, new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
    }

    @Override
    protected void onPause() {
        super.onPause();
        // The following call pauses the rendering thread.
        // If your OpenGL application is memory intensive,
        // you should consider de-allocating objects that
        // consume significant memory here.
        mGLView.onPause();
    }

    @Override
    protected void onResume() {
        super.onResume();
        // The following call resumes a paused rendering thread.
        // If you de-allocated graphic objects for onPause()
        // this is a good place to re-allocate them.
        mGLView.onResume();
    }
}

Classe MySurfaceView:

class MySurfaceView extends GLSurfaceView{

    public MySurfaceView(NightCamActivity context){
        super(context);
        // Create an OpenGL ES 2.0 context.
        Debug.out("Mysurfaceview welcome");
        setEGLContextClientVersion(2);
        // Set the Renderer for drawing on the GLSurfaceView
        MyRenderer renderer = new MyRenderer();
        renderer.takeContext(context);
        context.surface_view.renderer = renderer;
        setRenderer(renderer);
    }
}

CameraSurfaceView class:

public class CameraSurfaceView extends SurfaceView implements SurfaceHolder.Callback, PreviewCallback  {

    private Camera camera;
    Camera.Size use_size;
    MyRenderer renderer;

    public CameraSurfaceView(Context context) {
        super(context);
        SurfaceHolder holder = getHolder();
        holder.addCallback(this);
        Debug.out("Init CSV");
        camera = Camera.open();
    }

    public void surfaceCreated(SurfaceHolder holder) {
        Debug.out("SC");
        try {
            camera.setPreviewDisplay(holder);
        } catch (IOException e) {
            Debug.out("Could not set preview display for camera.");
        }
        camera.setPreviewCallback(this);
    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        // Surface will be destroyed when we return, so stop the preview.
        // Because the CameraDevice object is not a shared resource, it's very
        // important to release it when the activity is paused.
        try {
            if (camera != null) {
                camera.stopPreview();  
                camera.release();
            }
        } catch (Exception e) {
            Debug.out("Camera release failure.");
        }
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        Camera.Parameters parameters = camera.getParameters();
        List<Camera.Size> supportedPreviewSizes = parameters.getSupportedPreviewSizes();
        Camera.Size optimalPreviewSize = getOptimalPreviewSize(supportedPreviewSizes, w, h);
        if (optimalPreviewSize != null) {
            parameters.setPreviewSize(optimalPreviewSize.width, optimalPreviewSize.height);
            camera.setParameters(parameters);
            camera.startPreview();
        }
    }
    static Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int w, int h) {
        final double ASPECT_TOLERANCE = 0.1;
        final double MAX_DOWNSIZE = 1.5;

        double targetRatio = (double) w / h;
        if (sizes == null) return null;

        Camera.Size optimalSize = null;
        double minDiff = Double.MAX_VALUE;

        int targetHeight = h;

        // Try to find an size match aspect ratio and size
        for (Camera.Size size : sizes) {
            double ratio = (double) size.width / size.height;
            double downsize = (double) size.width / w;
            if (downsize > MAX_DOWNSIZE) {
                //if the preview is a lot larger than our display surface ignore it
                //reason - on some phones there is not enough heap available to show the larger preview sizes 
                continue;
            }
            if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
            if (Math.abs(size.height - targetHeight) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - targetHeight);
            }
        }

        // Cannot find the one match the aspect ratio, ignore the requirement
        //keep the max_downsize requirement
        if (optimalSize == null) {
            minDiff = Double.MAX_VALUE;
            for (Camera.Size size : sizes) {
                double downsize = (double) size.width / w;
                if (downsize > MAX_DOWNSIZE) {
                    continue;
                }
                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }
        }
        //everything else failed, just take the closest match
        if (optimalSize == null) {
            minDiff = Double.MAX_VALUE;
            for (Camera.Size size : sizes) {
                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }
        }

        return optimalSize;
    }

    public void onPreviewFrame(byte[] data, Camera arg1) {
        Debug.out("PREVIEW FRAME:");
        byte[] pixels = new byte[use_size.width * use_size.height * 3]; ;
        decodeYUV420SP(pixels, data, use_size.width,  use_size.height); 
        renderer.bindCameraTexture(pixels, use_size.width,  use_size.height);
    }

    void decodeYUV420SP(byte[] 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*3] = (byte) (b << 6);
                rgb[yp*3 + 1] = (byte) (b >> 2);
                rgb[yp*3 + 2] = (byte) (b >> 10);
            }  
        }  
    }  

}

enfin la classe MyRender:

public class MyRenderer implements GLSurfaceView.Renderer{
    private FloatBuffer vertices;
    private FloatBuffer texcoords;
    private int mProgram;
    private int maPositionHandle;
    private int gvTexCoordHandle;
    private int gvSamplerHandle;
    private static Context context;
    int[] camera_texture;
    public void onSurfaceCreated(GL10 unused, EGLConfig config) {
        initShapes();
        GLES20.glClearColor(0.0f, 1.0f, 0.2f, 1.0f);
        Debug.out("Hello init.");
        //Shaders
        int vertexShader = 0;
        int fragmentShader = 0;
        try {
            vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, readFile("vertex.vsh"));
            fragmentShader = loadShader(GLES20.GL_FRAGMENT_SHADER, readFile("fragment.fsh"));
        } catch (IOException e) {
            Debug.out("The shaders could not be found.");
            e.printStackTrace();
        }
        mProgram = GLES20.glCreateProgram();             // create empty OpenGL Program
        GLES20.glAttachShader(mProgram, vertexShader);   // add the vertex shader to program
        GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program
        GLES20.glLinkProgram(mProgram);                  // creates OpenGL program executables
        // get handles
        maPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");
        gvTexCoordHandle = GLES20.glGetAttribLocation(mProgram, "a_texCoord");
        gvSamplerHandle = GLES20.glGetAttribLocation(mProgram, "s_texture");
        GLES20.glPixelStorei(GLES20.GL_UNPACK_ALIGNMENT, 1);
        camera_texture = null;
    }


    private void initShapes(){
        float triangleCoords[] = {
            // X, Y, Z
            -1.0f, -1.0f, 0.0f,
             1.0f, -1.0f, 0.0f,
             -1.0f, 1.0f, 0.0f,
             1.0f,  1.0f, 0.0f,
        }; 
        float texcoordf[] = {
            // X, Y, Z
            -1.0f,-1.0f,
            1.0f,-1.0f,
            -1.0f,1.0f,
            1.0f,1.0f,
        };

        // initialize vertex Buffer for vertices
        ByteBuffer vbb = ByteBuffer.allocateDirect(triangleCoords.length * 4); 
        vbb.order(ByteOrder.nativeOrder());// use the device hardware's native byte order
        vertices = vbb.asFloatBuffer();  // create a floating point buffer from the ByteBuffer
        vertices.put(triangleCoords);    // add the coordinates to the FloatBuffer
        vertices.position(0);            // set the buffer to read the first coordinate
        // initialize vertex Buffer for texcoords 
        vbb = ByteBuffer.allocateDirect(texcoordf.length * 4); 
        vbb.order(ByteOrder.nativeOrder());// use the device hardware's native byte order
        texcoords = vbb.asFloatBuffer();  // create a floating point buffer from the ByteBuffer
        texcoords.put(texcoordf);    // add the coordinates to the FloatBuffer
        texcoords.position(0);            // set the buffer to read the first coordinate
    }

    private static String readFile(String path) throws IOException {
        AssetManager assetManager = context.getAssets();
        InputStream stream = assetManager.open(path);
        try {
            return new Scanner(stream).useDelimiter("A").next();
        }
        finally {
            stream.close();
        }
    }

    private int loadShader(int type, String shaderCode){
        // create a vertex shader type (GLES20.GL_VERTEX_SHADER)
        // or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
        int shader = GLES20.glCreateShader(type); 
        // add the source code to the shader and compile it
        GLES20.glShaderSource(shader, shaderCode);
        GLES20.glCompileShader(shader);
        return shader;
    }

    public void onDrawFrame(GL10 unused) {
        GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
        if(camera_texture == null){
            return;
        }
        // Add program to OpenGL environment
        GLES20.glUseProgram(mProgram);
        // Prepare the triangle data
        GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false, 0, vertices);
        GLES20.glVertexAttribPointer(gvTexCoordHandle, 2, GLES20.GL_FLOAT, false, 0, texcoords);
        GLES20.glEnableVertexAttribArray(maPositionHandle);
        GLES20.glEnableVertexAttribArray(gvTexCoordHandle);
        GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
        GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, camera_texture[0]);
        GLES20.glUniform1i(gvSamplerHandle, 0);
        // Draw the triangle
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
        GLES20.glDisableVertexAttribArray(maPositionHandle);
        GLES20.glDisableVertexAttribArray(gvTexCoordHandle);
    }

    public void onSurfaceChanged(GL10 unused, int width, int height) {
        GLES20.glViewport(0, 0, width, height);
    }

    public void takeContext(Context ocontext) {
        Debug.out("Take context");
        context = ocontext;
    }

    void bindCameraTexture(byte[] data,int w,int h) {
        byte[] pixels = new byte[256*256*3];
        for(int x = 0;x < 256;x++){
            for(int y = 0;x < 256;x++){
                pixels[x*256+y] = data[x*w+y];
            }
        }
        if (camera_texture==null){
            camera_texture=new int[1];
        }else{
            GLES20.glDeleteTextures(1, camera_texture, 0);
        }   
        GLES20.glGenTextures(1, camera_texture, 0);
        int tex = camera_texture[0];
        GLES20.glBindTexture(GL10.GL_TEXTURE_2D, tex);
        GLES20.glTexImage2D(GL10.GL_TEXTURE_2D, 0, GL10.GL_RGB, 256, 256, 0, GL10.GL_RGB, GL10.GL_UNSIGNED_BYTE, ByteBuffer.wrap(pixels));
        GLES20.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_LINEAR);
    }
}