Lipreading is like reading...

Lipreading is like reading a handwritten text, on a moving, dynamic display that shows only two to three letters at a time.

Handwritten, so very personal. Some people have clear handwriting, other people's handwriting is sloppy. Some write large letters, others tiny. Even within a person, there are differences. If you're in a hurry, your handwriting deteriorates. If you write a text while you focus on the content - on what you want to write - instead of on the act of handwriting: your handwriting deteriorates.

In handwritten text, many letters are ambiguous when seen in isolation. Even whole words can be hard to recognize when taken out of context. Yet when you can see the entire sentence, letters and words are easy to read.

In printed text, letters are standardised - once you've got used to a certain font, each a looks the same, as does each b, c, and the rest of the alphabet. There's a recognizable space to indicate the end of one word, and the beginning of the next, and punctuation marks to indicate breaks and endings. In handwritten text, the letters are variable in form; their shapes are not standard, but influenced by the location in a word (beginning, middle, or ending) and the letters before and after. And words may run into each other.


To read handwritten text, we prefer good lighting, good paper, a good pen, and good contrast between paper and pen.

Last but not least: the content must be interesting, or we don't even bother to try.  As an example, a picture of a handwritten note, that I found on the internet.

All of this applies to a lipreader trying to lipread a speaker: speech is personal, ambiguous, variable, and we lipreaders need all the help we can get - or we give up before we've even started.

What makes lipreading even more difficult than reading handwritten text, is that the display (the speakers head) moves. Very few speakers will look the lipreader in the eye for more than a few sentences. People look away because they are embarrassed by the lipreader's attention, because something catches their eye, because they have to think, or because they're just used to moving their head, body and hands while they speak.

Worst of all, though, is that the lipreader sees only two to three letters at a time. I'll try and make an animation to show what that looks like for reading handwritten text. For now, try and imagine reading the handwritten note above, through a moving window that lets you see just two or three letters at a time. Difficult? Yes!
Now increase the speed to 14 - 25  letters per second. Impossible? Yes!

Yet that's what lipreaders do.

Somehow.