private static boolean isExtendedWebpSupported() {
    // Lossless and extended formats are supported on Android 4.2.1+
    // Unfortunately SDK_INT is not enough to distinguish 4.2 and 4.2.1
    // (both are API level 17 (JELLY_BEAN_MR1))
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN_MR1) {
      return false;
    }

    if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN_MR1) {
      // Let's test if extended webp is supported
      // To this end we will try to decode bounds of vp8x webp with alpha channel
      byte[] decodedBytes = Base64.decode(VP8X_WEBP_BASE64, Base64.DEFAULT);
      BitmapFactory.Options opts = new BitmapFactory.Options();
      opts.inJustDecodeBounds = true;
      BitmapFactory.decodeByteArray(decodedBytes, 0, decodedBytes.length, opts);

      // If Android managed to find appropriate decoder then opts.outHeight and opts.outWidth
      // should be set. We can not assume that outMimeType is set.
      // Android guys forgot to update logic for mime types when they introduced support for webp.
      // For example, on 4.2.2 this field is not set for webp images.
      if (opts.outHeight != 1 || opts.outWidth != 1) {
        return false;
      }
    }

    return true;
  }
Checks whether underlying platform supports extended WebPs
fbcore/src/main/java/com/facebook/common/webp/WebpSupportStatus.java