code: private void CheckCIELab(IfdTags metadata, int n) {
      // BitsPerSample
      if (!metadata.containsTagId(TiffTags.getTagId("BitsPerSample"))) {
        validation.addErrorLoc("Missing BitsPerSample", "IFD" + n);
      } else {
        for (abstractTiffType vi : metadata.get(TiffTags.getTagId("BitsPerSample")).getValue()) {
          if (vi.toInt() != 8) {
            validation.addError("Invalid BitsPerSample", "IFD" + n, vi.toInt());
            break;
          }
        }
      }
    }
docs: Check CIELab.
  
  @param metadata the metadata
  @param n the IFD number