我可以从android中的uri获取图像文件的宽度和高度吗？

Question

i can getting the image width through MediaStore.Images.Media normally

but i need to getting the image width and height from image which selected from dropbox

so currently i have following method to getting image size from dropbox

private void getDropboxIMGSize(Uri uri){
    String size = Long.toString(new File(uri.getPath()).length());
    return size;
}

but what i actually need are getting the file width and height value

anyone know how to achieve that?please help!

Answer 1

private void getDropboxIMGSize(Uri uri){
   BitmapFactory.Options options = new BitmapFactory.Options();
   options.inJustDecodeBounds = true;
   BitmapFactory.decodeFile(new File(uri.getPath()).getAbsolutePath(), options);
   int imageHeight = options.outHeight;
   int imageWidth = options.outWidth;
 
}

no there is no way. You have to create a Bitmap object. if you use the inJustDecodeBounds flag the bitmap would not be loaded in memory. In fact BitmapFactory.decodeFile will return null. In my example uri is the phisical path to the image

Answer 2

Blackbelt's answer is correct if you have a file uri. However, if you are using the new file providers as in the official camera tutorial , it won't work. This works for that case:

BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(
        getContext().getContentResolver().openInputStream(mPhotoUri),
        null,
        options);
int imageHeight = options.outHeight;
int imageWidth = options.outWidth;

Answer 3

Blackbelt's answer will work most of the time using Options , but I would like to propose another solution or fallback solution by using the ExifInterface . If you have the image URI, you can create the ExifInterface using the full path, no need for Bitmap object nor BitmapFactory.Options .

ex.

int width = exif.getAttributeInt( ExifInterface.TAG_IMAGE_WIDTH, defaultValue );
int height = exif.getAttributeInt( ExifInterface.TAG_IMAGE_LENGTH, defaultValue ); 

Answer 4

This set of utilities to work with the Size abstraction in Android.

It contains an class SizeFromImage.java You can use it like this:

ISize size = new SizeFromImage(imgFilePath);
size.width();
size.hight();

Answer 5

解决方案是使用new File(uri.getPath()).getAbsolutePath()而不是uri.toString()

Answer 6

In addition to @Blackbelt answer you should use the following code to retrieve file path from Uri:

public static String getPathFromURI(Context context, Uri contentUri) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT &&
            DocumentsContract.isDocumentUri(context, contentUri)) {
        return getPathForV19AndUp(context, contentUri);
    } else {
        return getPathForPreV19(context, contentUri);
    }
}

private static String getPathForPreV19(Context context, Uri contentUri) {
    String[] projection = { MediaStore.Images.Media.DATA };
    Cursor cursor = context.getContentResolver().query(contentUri, projection, null, null, null);
    if (cursor != null && cursor.moveToFirst()) {
        try {
            int columnIndex = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            return cursor.getString(columnIndex);
        } finally {
            cursor.close();
        }
    }

    return null;
}

@TargetApi(Build.VERSION_CODES.KITKAT)
private static String getPathForV19AndUp(Context context, Uri contentUri) {
    String documentId = DocumentsContract.getDocumentId(contentUri);
    String id = documentId.split(":")[1];

    String[] column = { MediaStore.Images.Media.DATA };
    String sel = MediaStore.Images.Media._ID + "=?";
    Cursor cursor = context.getContentResolver().
            query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                    column, sel, new String[]{ id }, null);

    if (cursor != null) {
        try {
            int columnIndex = cursor.getColumnIndex(column[0]);
            if (cursor.moveToFirst()) {
                return cursor.getString(columnIndex);
            }
        } finally {
            cursor.close();
        }
    }

    return null;
}

Answer 7

The accepted answer returns with me a 0 of width/height, by replacing uri.getPath() with uri.getLastPathSegment(), it returns the correct dimensions

public static int[] getImageDimension(Uri uri){
    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(new File(uri.getLastPathSegment()).getAbsolutePath(), options);
    return new int[]{options.outWidth, options.outHeight};
}

Answer 8

For folks having content uri (starting with content:// ), open an InputStream & decode that stream to avoid getting 0 width and height. I'll use Kotlin

val uri: Uri = ....

val options = BitmapFactory.Options().apply { inJustDecodeBounds = true }
val inputStream = contentResolver.openInputStream(uri)
BitmapFactory.decodeStream(inputStream, null, options)

val width = options.outWidth
val height = options.outHeight

Answer 9

Please use InputStream:

public int[] getImageSize(Uri uri){
    try {
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        InputStream input = this.getContentResolver().openInputStream(uri);
        BitmapFactory.decodeStream(input, null, options);  input.close();
        return new int[]{options.outWidth, options.outHeight};
    }
    catch (Exception e){}
    return new int[]{0,0};
}

It'll return in array form:

int[]{ width , height }

Answer 10

If you guys keep getting (0,0) in the width and height, you probably want to decode a stream, and not a file.

It probably because you're trying to read an image from the assets. Try this:

val b = BitmapFactory.decodeStream(context.assets.open("path/in/assets/img.png"))
val width = b.width
val height = b.height