This topic is a few months old and while it debates the technical merits of this library it's worth pointing out that this is NOT a "free" library. While the author says it's free and it's under the GNU free software license...
"That's why it's under the GNU license."
... it is not free. He requires a $5 "donation" in order to download it. In reading his site it seriously comes across like one of those late night "paid advertisement" TV shows. So, technically, he's in violation of the GNU license as one cannot charge for source code if it's under the license. I think it's ok to charge for one's work but only if one is upfront about it and claims that's what he's doing. Saying that it's a "donation" and that it's "free" software under the Gnu license and then requiring payment to download is not compatible. It's not free, it's a one-time license fee.
... it is not free. He requires a $5 "donation" in order to download it.
Don't worry about it. There are lots of scams on the web and this is just one of them. The software isn't worth anything at all.
If you want to try out the approach, read the application note and write your own 3-4 lines of code to implement it.
recurry:
So, technically, he's in violation of the GNU license as one cannot charge for source code if it's under the license. I think it's ok to charge for one's work but only if one is upfront about it and claims that's what he's doing. Saying that it's a "donation" and that it's "free" software under the Gnu license and then requiring payment to download is not compatible. It's not free, it's a one-time license fee.
recurry, please read the following article from the GNU oganization. You misunderstand the GNU GPL license completely.
Directly from the GNU Free Software Foundation:
Selling Free Software - GNU Project - Free Software Foundation <--seriously, read the whole article.
"Many people believe that the spirit of the GNU Project is that you should not charge money for distributing copies of software, or that you should charge as little as possible—just enough to cover the cost. This is a misunderstanding.
Actually, we encourage people who redistribute free software to charge as much as they wish or can. If a license does not permit users to make copies and sell them, it is a nonfree license. If this seems surprising to you, please read on."
...
"Since free software is not a matter of price, a low price doesn't make the software free, or even closer to free. So if you are redistributing copies of free software, you might as well charge a substantial fee and make some money. Redistributing free software is a good and legitimate activity; if you do it, you might as well make a profit from it."
I've done prob. a dozen hrs of reading about licenses over the last couple yrs, to make sure I fully understood and was in compliance. If you have any other questions I'll do my best to answer them.
~GS
recurry:
In reading his site it seriously comes across like one of those late night "paid advertisement" TV shows.
Can you please be more specific? Perhaps I have some things to consider changing or working on.