@Nullable
  @Override
  public CacheKey getPostprocessorCacheKey() {
    if (mCacheKey == null) {
      if (mEnableAntiAliasing) {
        mCacheKey = new SimpleCacheKey("RoundAsCirclePostprocessor#AntiAliased");
      } else {
        mCacheKey = new SimpleCacheKey("RoundAsCirclePostprocessor");
      }
    }
    return mCacheKey;
  }
Postprocessor that rounds a given image as a circle.
native-filters/src/main/java/com/facebook/imagepipeline/postprocessors/RoundAsCirclePostprocessor.java