如何在没有ExifInterface的情况下确定图片的方向？

Question

我将图片加载到bitmap并需要知道拍摄照片的方向（来自相机）才能正确显示。使用以下代码的方法很有效（从API级别5开始），但如果android:minSdkVersion="4"怎么办？还有另一种方式吗？

ExifInterface exif = new ExifInterface(SourceFileName);     //Since API Level 5
String exifOrientation = exif.getAttribute(ExifInterface.TAG_ORIENTATION);

Answer 1

Matrix matrix = new Matrix();

ExifInterface exifReader = new ExifInterface(filePath);

int orientation = exifReader.getAttributeInt(ExifInterface.TAG_ORIENTATION, -1);

if (orientation ==ExifInterface.ORIENTATION_NORMAL) {

// Do nothing. The original image is fine.
} else if (orientation == ExifInterface.ORIENTATION_ROTATE_90) {

       matrix.postRotate(90);

} else if (orientation == ExifInterface.ORIENTATION_ROTATE_180) {

       matrix.postRotate(180);

} else if (orientation == ExifInterface.ORIENTATION_ROTATE_270) {

       matrix.postRotate(270);

}

Answer 2

轻松实现自己的exif reader

然后

Metadata metadata = JpegMetadataReader.readMetadata(new File(imagePath));
Directory jpegDirectory = metadata.getDirectory(JpegDirectory.class);
 int height = jpg.GetImageHeight();
 int width = jpg.GetImageWidth();