code: public Dimension getMinDimension() {
      long effWithMin = getEffectiveMinWidth();
      long effHeightMin = getEffectiveMinHeight();
      double effRatio = getRatio();
  
      if (effWithMin == 0 && effHeightMin > 0 && effRatio > 0) {
        effWithMin = Math.round(effHeightMin * effRatio);
      }
      if (effWithMin > 0 && effHeightMin == 0 && effRatio > 0) {
        effHeightMin = Math.round(effWithMin / effRatio);
      }
  
      if (effWithMin > 0 || effHeightMin > 0) {
        return new Dimension(effWithMin, effHeightMin);
      }
      else {
        return null;
      }
    }
docs: Get minimum dimensions for media format. If only with or height is defined the missing dimensions
  is calculated from the ratio. If no ratio defined either only width or height dimension is returned.
  If neither width or height are defined null is returned.
  @return Min. dimensions or null