如何正确设置Android相机方向？

我想在Android中根据设备方向设置相机方向，但似乎没有任何工作。 我尝试旋转Surface以及相机参数，但纵向模式下的相机预览始终颠倒过来。 我需要顺时针旋转90度，才能正确。 这是我现在使用的代码，只能在横向模式下工作。

SurfaceHolder.Callback surfaceCallback = new SurfaceHolder.Callback() { @Override public void surfaceDestroyed(SurfaceHolder holder) { camera.stopPreview(); camera.release(); camera = null; } @Override public void surfaceCreated(SurfaceHolder holder) { initCamera(); } private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) { final double ASPECT_TOLERANCE = 0.2; double targetRatio = (double) w / h; if (sizes == null) return null; Size optimalSize = null; double minDiff = Double.MAX_VALUE; int targetHeight = h; // Try to find an size match aspect ratio and size for (Size size : sizes) { Log.d(TAG, "Checking size " + size.width + "w " + size.height + "h"); double ratio = (double) size.width / size.height; 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 if (optimalSize == null) { minDiff = Double.MAX_VALUE; for (Size size : sizes) { if (Math.abs(size.height - targetHeight) < minDiff) { optimalSize = size; minDiff = Math.abs(size.height - targetHeight); } } } return optimalSize; } @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { Camera.Parameters parameters = camera.getParameters(); List<Size> sizes = parameters.getSupportedPreviewSizes(); Size optimalSize = getOptimalPreviewSize(sizes, width, height); Log.d(TAG, "Surface size is " + width + "w " + height + "h"); Log.d(TAG, "Optimal size is " + optimalSize.width + "w " + optimalSize.height + "h"); parameters.setPreviewSize(optimalSize.width, optimalSize.height); // parameters.setPreviewSize(width, height); camera.setParameters(parameters); camera.startPreview(); } }; 

Answer 1

从其他成员和我的问题：

相机旋转问题取决于不同的设备和某些版本。

版本1.6：修复旋转问题，对大多数设备都有好处

 if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) { p.set("orientation", "portrait"); p.set("rotation",90); } if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) { p.set("orientation", "landscape"); p.set("rotation", 90); } 

版本2.1：取决于设备types，例如，Cannt修复XPeria X10的问题，但它对X8和Mini

 Camera.Parameters parameters = camera.getParameters(); parameters.set("orientation", "portrait"); camera.setParameters(parameters); 

版本2.2：不适用于所有设备

 camera.setDisplayOrientation(90); 

http://code.google.com/p/android/issues/detail?id=1193#c42

Answer 2

从Javadocs的setDisplayOrientation(int) （需要API级别9）：

  public static void setCameraDisplayOrientation(Activity activity, int cameraId, android.hardware.Camera camera) { android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo(); android.hardware.Camera.getCameraInfo(cameraId, info); int rotation = activity.getWindowManager().getDefaultDisplay() .getRotation(); int degrees = 0; switch (rotation) { case Surface.ROTATION_0: degrees = 0; break; case Surface.ROTATION_90: degrees = 90; break; case Surface.ROTATION_180: degrees = 180; break; case Surface.ROTATION_270: degrees = 270; break; } int result; if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) { result = (info.orientation + degrees) % 360; result = (360 - result) % 360; // compensate the mirror } else { // back-facing result = (info.orientation - degrees + 360) % 360; } camera.setDisplayOrientation(result); } 

Answer 3

该解决scheme将适用于所有版本的Android。 您可以在Java中使用reflection使其适用于所有Android设备：

基本上你应该创build一个reflection包装来调用Android 2.2 setDisplayOrientation，而不是调用具体的方法。

方法：

  protected void setDisplayOrientation(Camera camera, int angle){ Method downPolymorphic; try { downPolymorphic = camera.getClass().getMethod("setDisplayOrientation", new Class[] { int.class }); if (downPolymorphic != null) downPolymorphic.invoke(camera, new Object[] { angle }); } catch (Exception e1) { } } 

而不是使用camera.setDisplayOrientation（x）使用setDisplayOrientation（camera，x） ：

  if (Integer.parseInt(Build.VERSION.SDK) >= 8) setDisplayOrientation(mCamera, 90); else { if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) { p.set("orientation", "portrait"); p.set("rotation", 90); } if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) { p.set("orientation", "landscape"); p.set("rotation", 90); } } 

Answer 4

我在使用ZBar扫描标签时遇到了这个问题。 相机方向问题。 使用下面的代码我能够解决问题。 这不是整个代码片段，请从中获取帮助。

  public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { if (isPreviewRunning) { mCamera.stopPreview(); } setCameraDisplayOrientation(mCamera); previewCamera(); } public void previewCamera() { try { // Hard code camera surface rotation 90 degs to match Activity view // in portrait mCamera.setPreviewDisplay(mHolder); mCamera.setPreviewCallback(previewCallback); mCamera.startPreview(); mCamera.autoFocus(autoFocusCallback); isPreviewRunning = true; } catch (Exception e) { Log.d("DBG", "Error starting camera preview: " + e.getMessage()); } } public void setCameraDisplayOrientation(android.hardware.Camera camera) { Camera.Parameters parameters = camera.getParameters(); android.hardware.Camera.CameraInfo camInfo = new android.hardware.Camera.CameraInfo(); android.hardware.Camera.getCameraInfo(getBackFacingCameraId(), camInfo); Display display = ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay(); int rotation = display.getRotation(); int degrees = 0; switch (rotation) { case Surface.ROTATION_0: degrees = 0; break; case Surface.ROTATION_90: degrees = 90; break; case Surface.ROTATION_180: degrees = 180; break; case Surface.ROTATION_270: degrees = 270; break; } int result; if (camInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) { result = (camInfo.orientation + degrees) % 360; result = (360 - result) % 360; // compensate the mirror } else { // back-facing result = (camInfo.orientation - degrees + 360) % 360; } camera.setDisplayOrientation(result); } private int getBackFacingCameraId() { int cameraId = -1; // Search for the front facing camera int numberOfCameras = Camera.getNumberOfCameras(); for (int i = 0; i < numberOfCameras; i++) { Camera.CameraInfo info = new Camera.CameraInfo(); Camera.getCameraInfo(i, info); if (info.facing == Camera.CameraInfo.CAMERA_FACING_BACK) { cameraId = i; break; } } return cameraId; } 

Answer 5

我最终使用Google的相机应用程序解决了这个问题。 它通过使用传感器获取手机的方向，然后适当设置EXIF标签。 从相机出来的JPEG不是自动定向的。

另外，只有在横向模式下，相机预览才能正常工作。 如果您需要将活动布局设置为纵向，则必须使用方向传感器的值手动执行。

Answer 6

这个问题很久以前就解决了，但是我遇到了一些困难，把所有的东西拼在一起，所以这里是我的最终解决scheme，我希望这能帮助其他人：

 public void startPreview() { try { Log.i(TAG, "starting preview: " + started); // .... Camera.CameraInfo camInfo = new Camera.CameraInfo(); Camera.getCameraInfo(cameraIndex, camInfo); int cameraRotationOffset = camInfo.orientation; // ... Camera.Parameters parameters = camera.getParameters(); List<Camera.Size> previewSizes = parameters.getSupportedPreviewSizes(); Camera.Size previewSize = null; float closestRatio = Float.MAX_VALUE; int targetPreviewWidth = isLandscape() ? getWidth() : getHeight(); int targetPreviewHeight = isLandscape() ? getHeight() : getWidth(); float targetRatio = targetPreviewWidth / (float) targetPreviewHeight; Log.v(TAG, "target size: " + targetPreviewWidth + " / " + targetPreviewHeight + " ratio:" + targetRatio); for (Camera.Size candidateSize : previewSizes) { float whRatio = candidateSize.width / (float) candidateSize.height; if (previewSize == null || Math.abs(targetRatio - whRatio) < Math.abs(targetRatio - closestRatio)) { closestRatio = whRatio; previewSize = candidateSize; } } int rotation = getWindowManager().getDefaultDisplay().getRotation(); int degrees = 0; switch (rotation) { case Surface.ROTATION_0: degrees = 0; break; // Natural orientation case Surface.ROTATION_90: degrees = 90; break; // Landscape left case Surface.ROTATION_180: degrees = 180; break;// Upside down case Surface.ROTATION_270: degrees = 270; break;// Landscape right } int displayRotation; if (isFrontFacingCam) { displayRotation = (cameraRotationOffset + degrees) % 360; displayRotation = (360 - displayRotation) % 360; // compensate // the // mirror } else { // back-facing displayRotation = (cameraRotationOffset - degrees + 360) % 360; } Log.v(TAG, "rotation cam / phone = displayRotation: " + cameraRotationOffset + " / " + degrees + " = " + displayRotation); this.camera.setDisplayOrientation(displayRotation); int rotate; if (isFrontFacingCam) { rotate = (360 + cameraRotationOffset + degrees) % 360; } else { rotate = (360 + cameraRotationOffset - degrees) % 360; } Log.v(TAG, "screenshot rotation: " + cameraRotationOffset + " / " + degrees + " = " + rotate); Log.v(TAG, "preview size: " + previewSize.width + " / " + previewSize.height); parameters.setPreviewSize(previewSize.width, previewSize.height); parameters.setRotation(rotate); camera.setParameters(parameters); camera.setPreviewDisplay(mHolder); camera.startPreview(); Log.d(TAG, "preview started"); started = true; } catch (IOException e) { Log.d(TAG, "Error setting camera preview: " + e.getMessage()); } } 

Answer 7

看看这个解决scheme

  public static void setCameraDisplayOrientation(Activity activity, int cameraId, android.hardware.Camera camera) { android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo(); android.hardware.Camera.getCameraInfo(cameraId, info); int rotation = activity.getWindowManager().getDefaultDisplay() .getRotation(); int degrees = 0; switch (rotation) { case Surface.ROTATION_0: degrees = 0; break; case Surface.ROTATION_90: degrees = 90; break; case Surface.ROTATION_180: degrees = 180; break; case Surface.ROTATION_270: degrees = 270; break; } int result; if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) { result = (info.orientation + degrees) % 360; result = (360 - result) % 360; // compensate the mirror } else { // back-facing result = (info.orientation - degrees + 360) % 360; } camera.setDisplayOrientation(result); }