我通过onActivityResult上的相机从相机传递位图。
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
ContentValues values = new ContentValues();
values.put(MediaStore.Images.Media.TITLE, "picture");
mCapturedImageURI = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
intent.putExtra(MediaStore.EXTRA_OUTPUT, mCapturedImageURI);
startActivityForResult(intent, REQUEST_TAKE_PHOTO);
我可以获得位图：
Bitmap bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), mCapturedImageURI);
但是，我注意到图像在某些设备上旋转。在这里搜索帖子后，典型的解决方案似乎通过以下方式获得轮换：
String path = mCapturedImageURI.getPath();
ExifInterface exif = new ExifInterface(path);
int rotation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);
不幸的是，即使旋转了位图，我的int rotation始终为0。
当我上传设备上的图片但方向仍然是0时，我也尝试了这个功能：
String[] orientationColumn = {MediaStore.Images.Media.ORIENTATION};
Cursor cur = managedQuery(mCapturedImageURI, orientationColumn, null, null, null);
if (cur != null && cur.moveToFirst()) {
orientation = cur.getInt(cur.getColumnIndex(orientationColumn[0]));
}
任何人都可以看到我在这里做错了什么？还是另一种解决方法？
通常，位图与后置摄像头逆时针旋转90度，前摄像头顺时针旋转90度。在Moto G上运行正常。在Galaxy S3和LG G2上旋转。
答案 0 :(得分：6)
尝试使用内容光标中的信息。
float photoRotation = 0;
boolean hasRotation = false;
String[] projection = { Images.ImageColumns.ORIENTATION };
try {
Cursor cursor = getActivity().getContentResolver().query(photoUri, projection, null, null, null);
if (cursor.moveToFirst()) {
photoRotation = cursor.getInt(0);
hasRotation = true;
}
cursor.close();
} catch (Exception e) {}
if (!hasRotation) {
ExifInterface exif = new ExifInterface(photoUri.getPath());
int exifRotation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION,
ExifInterface.ORIENTATION_UNDEFINED);
switch (exifRotation) {
case ExifInterface.ORIENTATION_ROTATE_90: {
photoRotation = 90.0f;
break;
}
case ExifInterface.ORIENTATION_ROTATE_180: {
photoRotation = 180.0f;
break;
}
case ExifInterface.ORIENTATION_ROTATE_270: {
photoRotation = 270.0f;
break;
}
}
}
答案 1 :(得分：4)
试试这种方式，希望这可以帮助您解决问题。
activity_main.xml中：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:gravity="center">
<ImageView
android:id="@+id/imgFromCameraOrGallery"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
android:src="@drawable/ic_launcher"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<Button
android:id="@+id/btnCamera"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content"
android:text="Camera"/>
<Button
android:id="@+id/btnGallery"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_marginLeft="5dp"
android:layout_height="wrap_content"
android:text="Gallery"/>
</LinearLayout>
</LinearLayout>
MainActivity.java：
public class MainActivity extends Activity {
private ImageView imgFromCameraOrGallery;
private Button btnCamera;
private Button btnGallery;
private String imgPath;
final private int PICK_IMAGE = 1;
final private int CAPTURE_IMAGE = 2;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imgFromCameraOrGallery = (ImageView) findViewById(R.id.imgFromCameraOrGallery);
btnCamera = (Button) findViewById(R.id.btnCamera);
btnGallery = (Button) findViewById(R.id.btnGallery);
btnCamera.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
final Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, setImageUri());
startActivityForResult(intent, CAPTURE_IMAGE);
}
});
btnGallery.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, ""), PICK_IMAGE);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == Activity.RESULT_OK) {
if (requestCode == CAPTURE_IMAGE) {
rotateImage(getImagePath());
} else if (requestCode == PICK_IMAGE) {
imgFromCameraOrGallery.setImageBitmap(BitmapFactory.decodeFile(getAbsolutePath(data.getData())));
}
}
}
private void rotateImage(final String path) {
runOnUiThread(new Runnable() {
@Override
public void run() {
Bitmap b = decodeFileFromPath(path);
try {
ExifInterface ei = new ExifInterface(path);
int orientation = ei.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);
Matrix matrix = new Matrix();
switch (orientation) {
case ExifInterface.ORIENTATION_ROTATE_90:
matrix.postRotate(90);
b = Bitmap.createBitmap(b, 0, 0, b.getWidth(), b.getHeight(), matrix, true);
break;
case ExifInterface.ORIENTATION_ROTATE_180:
matrix.postRotate(180);
b = Bitmap.createBitmap(b, 0, 0, b.getWidth(), b.getHeight(), matrix, true);
break;
case ExifInterface.ORIENTATION_ROTATE_270:
matrix.postRotate(270);
b = Bitmap.createBitmap(b, 0, 0, b.getWidth(), b.getHeight(), matrix, true);
break;
default:
b = Bitmap.createBitmap(b, 0, 0, b.getWidth(), b.getHeight(), matrix, true);
break;
}
} catch (Throwable e) {
e.printStackTrace();
}
FileOutputStream out1 = null;
File file;
try {
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
file = new File(Environment.getExternalStorageDirectory() + "/DCIM/", "image" + new Date().getTime() + ".jpg");
}
else {
file = new File(getFilesDir() , "image" + new Date().getTime() + ".jpg");
}
out1 = new FileOutputStream(file);
b.compress(Bitmap.CompressFormat.JPEG, 90, out1);
imgFromCameraOrGallery.setImageBitmap(BitmapFactory.decodeFile(file.getAbsolutePath()));
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
out1.close();
} catch (Throwable ignore) {
}
}
}
});
}
private Bitmap decodeFileFromPath(String path){
Uri uri = getImageUri(path);
InputStream in = null;
try {
in = getContentResolver().openInputStream(uri);
//Decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(in, null, o);
in.close();
int scale = 1;
int inSampleSize = 1024;
if (o.outHeight > inSampleSize || o.outWidth > inSampleSize) {
scale = (int) Math.pow(2, (int) Math.round(Math.log(inSampleSize / (double) Math.max(o.outHeight, o.outWidth)) / Math.log(0.5)));
}
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
in = getContentResolver().openInputStream(uri);
Bitmap b = BitmapFactory.decodeStream(in, null, o2);
in.close();
return b;
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
public String getAbsolutePath(Uri uri) {
if(Build.VERSION.SDK_INT >= 19){
String id = uri.getLastPathSegment().split(":")[1];
final String[] imageColumns = {MediaStore.Images.Media.DATA };
final String imageOrderBy = null;
Uri tempUri = getUri();
Cursor imageCursor = getContentResolver().query(tempUri, imageColumns,
MediaStore.Images.Media._ID + "="+id, null, imageOrderBy);
if (imageCursor.moveToFirst()) {
return imageCursor.getString(imageCursor.getColumnIndex(MediaStore.Images.Media.DATA));
}else{
return null;
}
}else{
String[] projection = { MediaStore.MediaColumns.DATA };
Cursor cursor = getContentResolver().query(uri, projection, null, null, null);
if (cursor != null) {
int column_index = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
} else
return null;
}
}
private Uri getUri() {
String state = Environment.getExternalStorageState();
if(!state.equalsIgnoreCase(Environment.MEDIA_MOUNTED))
return MediaStore.Images.Media.INTERNAL_CONTENT_URI;
return MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
}
private Uri getImageUri(String path) {
return Uri.fromFile(new File(path));
}
public Uri setImageUri() {
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
File file = new File(Environment.getExternalStorageDirectory() + "/DCIM/", "image" + new Date().getTime() + ".jpg");
Uri imgUri = Uri.fromFile(file);
this.imgPath = file.getAbsolutePath();
return imgUri;
}
else {
File file = new File(getFilesDir() , "image" + new Date().getTime() + ".jpg");
Uri imgUri = Uri.fromFile(file);
this.imgPath = file.getAbsolutePath();
return imgUri;
}
}
public String getImagePath() {
return imgPath;
}
}