| Code Value | Definition |
|---|---|
| C | Shadow cast |
| H | Hair, hat, veil, burqa, or other head covering (face only) |
| L | Eyelashes or reflections of eyelashes (iris only) |
| O | Any other occlusion, such as eyeglass frames blocking the image |
| R | Reflection of an object |
| S | Specularity, reflection of light |