code: public RectF getInterpolatedRect(long elapsedTime) {
          float elapsedTimeFraction = elapsedTime / (float) mDuration;
          float interpolationProgress = Math.min(elapsedTimeFraction, 1);
          float interpolation = mInterpolator.getInterpolation(interpolationProgress);
          float currentWidth = mSrcRect.width() + (interpolation * mWidthDiff);
          float currentHeight = mSrcRect.height() + (interpolation * mHeightDiff);
  
          float currentCenterX = mSrcRect.centerX() + (interpolation * mCenterXDiff);
          float currentCenterY = mSrcRect.centerY() + (interpolation * mCenterYDiff);
  
          float left = currentCenterX - (currentWidth / 2);
          float top = currentCenterY - (currentHeight / 2);
          float right = left + currentWidth;
          float bottom = top + currentHeight;
  
          mCurrentRect.set(left, top, right, bottom);
          return mCurrentRect;
      }
docs: Gets the current rect that represents the part of the image to take the scene
  in the current frame.
  @param elapsedTime the elapsed time since this transition started.