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如何正确设置Android相机方向？

我想根据Android中的设备方向设置相机方向，但似乎没有任何效果。 我尝试旋转Surface以及相机参数，但是纵向模式下的相机预览总是颠倒过来。 我需要顺时针旋转90度才能使其正确。 这是我现在使用的代码，仅适用于横向模式。

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 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 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();

}

};

7个解决方案

70 votes

从其他成员和我的问题：

Camera Rotation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：取决于设备的类型，例如，Cannt修复XPeria X10的问题，但它对X8和Mini都有好处

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]

LTEHUB answered 2019-09-09T10:51:51Z

32 votes

来自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);

}

Jason Robinson answered 2019-09-09T10:52:15Z

25 votes

此解决方案适用于所有Android版本。 您可以在Java中使用反射使其适用于所有Android设备：

基本上你应该创建一个反射包装来调用Android 2.2 setDisplayOrientation，而不是调用特定的方法。

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);

}

}

hnviet answered 2019-09-09T10:53:02Z

6 votes

当我使用ZBar在标签中进行扫描时，我遇到了问题。相机方向问题。 使用下面的代码，我能够解决问题。这不是整个代码段，请仅从此处获取帮助。

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;

}

DeepakPanwar answered 2019-09-09T10:53:28Z

5 votes

我终于使用谷歌的相机应用修复了这个问题。 它通过使用传感器获取手机的方向，然后适当地设置EXIF标签。 从相机发出的JPEG不会自动定向。

此外，相机预览仅在横向模式下正常工作。 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中的值手动完成。

Abhinav answered 2019-09-09T10:54:00Z

4 votes

很久以前这个问题就解决了，但我把所有部分放在一起遇到了一些困难所以这是我的最终解决方案，我希望这会有助于其他人：

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 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());

}

}

Louis GRIGNON answered 2019-09-09T10:54:24Z

3 votes

看看这个解决方案

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);

}

justchill answered 2019-09-09T10:54:48Z