Android - Ładowanie obrazów z Assets

Otóż mam pewien problem. Przerobiłem kod ładujący obrazy z resources na assets ( http://developer.android.com/training/displaying-bitmaps/load-bitmap.html ). *.jpg ładuje poprawnie a *.png nie chce załadować.

private Bitmap decodeSampledFromAssets(String path, int reqWidth, int reqHeight) {

		InputStream ims = null;

		try {

			ims = mContext.getAssets().open(path);

			final BitmapFactory.Options options = new BitmapFactory.Options();

			// 1
			options.inJustDecodeBounds = true;
			BitmapFactory.decodeStream(ims, null, options);
			options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
			options.inJustDecodeBounds = false;

			return BitmapFactory.decodeStream(ims, null, options);
		}
		catch (IOException e) {

			e.printStackTrace();
		}
		finally {

			if (ims != null) {
				try {
					ims.close();
				}
				catch (IOException e) {
					e.printStackTrace();
				}
			}
		}

		return null;
	}

protected 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) {

			final int halfHeight = height / 2;
			final int halfWidth = width / 2;

			// Calculate the largest inSampleSize value that is a power of 2 and keeps both
			// height and width larger than the requested height and width.
			while ((halfHeight / inSampleSize) > reqHeight
					&& (halfWidth / inSampleSize) > reqWidth) {
				inSampleSize *= 2;
			}
		}

		return inSampleSize;
	}

// przykładowe wywołanie

public void test(){
// ładuje
Bitmap bitmap = decodeSampledFromAssets("test1.jpg", 64, 64);
// nie ładuje
Bitmap bitmap = decodeSampledFromAssets("test2.png", 64, 64);
}