在我的应用程序中,我必须从相机捕获图像或从库导入,在活动的imageview中显示它。一切都很好,我从两者中获取图像,并且能够毫无例外地将其设置在imageview上。但有时图像没有得到适当的缩放和垂直拉伸或方向改变。请帮帮我。
以下是我的代码,用于解码官方Android文档中引用的图像:
public static Bitmap decodeSampledBitmapFromResource(File photoFile, int reqWidth, int reqHeight) {
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
try {
BitmapFactory.decodeStream(new FileInputStream(photoFile), null,
options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth,
reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeStream(new FileInputStream(photoFile),
null, options);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return null;
}
}
public static int calculateInSampleSize(BitmapFactory.Options options,
int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
// Calculate ratios of height and width to requested height and
// width
final int heightRatio = Math.round((float) height
/ (float) reqHeight);
final int widthRatio = Math.round((float) width / (float) reqWidth);
// Choose the smallest ratio as inSampleSize value, this will
// guarantee
// a final image with both dimensions larger than or equal to the
// requested height and width.
inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
}
return inSampleSize;
}
最佳答案
这些图像有不同的方向,因此在放置imageview时它会根据方向旋转。您可以从图像的属性检查照片的方向。
要以正确的方式设置图像,可以使用以下代码…
int rot=getCameraPhotoOrientation(this,Uri,picturePath);
if(rot!=0)
bitmap=new RotateOrientation().RotateOrientationCall(bitmap,rot);
GetCameraphotoOrientation方法:
public static int getCameraPhotoOrientation(Context context, Uri imageUri, String imagePath){
int rotate = 0;
try {
context.getContentResolver().notifyChange(imageUri, null);
File imageFile = new File(imagePath);
ExifInterface exif = new ExifInterface(
imageFile.getAbsolutePath());
int orientation = exif.getAttributeInt(
ExifInterface.TAG_ORIENTATION,
ExifInterface.ORIENTATION_NORMAL);
switch (orientation) {
case ExifInterface.ORIENTATION_ROTATE_270:
rotate = 270;
break;
case ExifInterface.ORIENTATION_ROTATE_180:
rotate = 180;
break;
case ExifInterface.ORIENTATION_ROTATE_90:
rotate = 90;
break;
}
Log.d(TAG, "Exit orientation: " + orientation);
} catch (Exception e) {
e.printStackTrace();
}
return rotate;
}
将RotateOrientation类添加到根据方向旋转类。
public class RotateOrientation {
Bitmap RotateOrientationCall(Bitmap src,float degree)
{
Matrix matrix=new Matrix();
matrix.postRotate(degree);
Bitmap bmOut = Bitmap.createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), matrix, true);
return bmOut;
}
}