[sane-devel] Re: Problems about Lineart mode

[m. allan noah]

On 1/26/07, Rodolfo Medina <rodolfo.medina at gmail.com> wrote:
> Rodolfo Medina <rodolfo.medina at gmail.com> writes:
>
> > I scan a document with:
> >
> >  $ scanimage --mode Lineart --resolution 150 -x 215 -y 297 > document
> >
> > , so obtaining a fine image about 250Kb big. But, the problem is that MS
> > Windows can't apparently see the file, and I need to send it to other people
> > non Linux users. On the other hand, if I omit the `--mode Lineart' option the
> > file comes up too big: 6Mb or so.
> >
> > Can anyone suggest a way to aquire a document so that the resultant file is:
> > 1) readable by MS Windows;
> > 2) as small as some 200Kb?
>
>
> "m. allan noah" <kitno455 at gmail.com> writes:
>
> > by default, scanimage outputs in the format 'PNM', so if they have a
> > viewer for that type on windows, they can view it. if they dont, you
> > can easily convert it to many other formats using a wide variety of
> > utilities on your linux box. which one you choose depends on what the
> > windows users will do with the file. my suggestion:
> >
> > scanimage --mode Lineart --resolution 150 -x 215 -y 297 | pnmtopng >
> > document.png
> >
> > you will have to have the utility pnmtopng installed, it is part of
> > the netpbm utils package.
> > the files will be readable in IE.
> >
> > another option instead is to use the tiff output format of scanimage
> > (--format tiff)
>
>
> Thanks indeed, your suggestion seems to work perfectly.
> But, when I try to use `pnmtopng' alone, with:
>
>  # pnmtopng document.pnm
>
> , the program fails: I get some messed output and nothing else.
> Why?

pnmtopng, like most unix programs, has built-in novice detection :)

seriously, it prints its output to stdout, just like scanimage does.
stdout is attached to your terminal. so you have to redirect it. try
this:

pnmtopng document.pnm > document.png

allan

-- 
"The truth is an offense, but not a sin"