public String getCompressedAverageBitsPerPixelDescription()
{
Rational value = _directory.getRational(ExifSubIFDDirectory.TAG_COMPRESSED_AVERAGE_BITS_PER_PIXEL);
if (value==null)
return null;
String ratio = value.toSimpleString(_allowDecimalRepresentationOfRationals);
if (value.isInteger() && value.intValue() == 1) {
return ratio + " bit/pixel";
} else {
return ratio + " bits/pixel";
}