About .jpg

[Sandy Fleming]

Hi Daniel, and everybody!

I notice Nana ignored my advice and did save it as .jpg, though  :)

To illustrate the point, if you open Nana's .jpg in a graphics editor and
zoom in closely, you'll see a lot of grey pixels around the black lines.
This is due to having edited and saved it as a .jpg.

It may not look too bad now, but if people edited it a lot, it would get
gradally worse.

So use .gif for SignWriting!  :)

Sandy

> -----Original Message-----
> From: SignWriting List [mailto:SW-L at ADMIN.HUMBERC.ON.CA]On Behalf Of
> Daniel Noelpp
> Sent: 02 October 2003 14:11
> To: SW-L at ADMIN.HUMBERC.ON.CA
> Subject: About .jpg
>
>
> Hello Sandy
>
> About the .jpg format you did an excellent job explaining it,
> but I need to explain why .jpg "ignores" some information.
>
> Sandy wrote:
>
> > If you do use .jpg, you'll find that smudging creeps into the
> image if you
> > edit it, because the .jpg format works by ignoring some of the
> information
> > in the image - it loses a little information every time you
> change it. The
> > ..gif format keeps all information, so your SignWriting will remain
> > crystal clear no matter how many times you edit the image!
>
> When storing a .jpg the colors in the picture are transformed
> in a spectrum. This is a mathematical representation to make
> compression easier. Now the funny part is that not the whole
> spectrum is saved. You even can tell Photoshop or many
> other software how much of the spectrum you want to save
> (as a slider or as a percent value). The better quality you have,
> the larger the file will be.
>
> This is a very clever trick because the smudging is almost
> inperceptible for photographic pictures. DVDs use a very
> similar trick to encode movies.
>
> So I hope you don't object to this small lesson even if the
> subject doesn't relate to SignWriting directly. Sandy is right:
> Don't use .jpg to save SignWriting texts!
>
> Cheers!
> Daniel
>