[GRASS-user] High Resolution ppm

[Hamish]

André wrote:
> Thank you for your hints, however I didn't managed to solve the problem.
> I installed NetPBM tools has you suggested, however I still get hundreds
> of .ppm files instead of one big high resolution file like I need.

the programs need to be in the system search %PATH% so that GRASS can
find them.


> I then tried Windows command prompt with these sentences:
> C:\Program Files (x86)\GnuWin32\bin>pnmcat -lr C:\Users\Andre\Pictures\aaa\E-W-45_1_1.ppm
> C:\Program Files (x86)\GnuWin32\bin>pnmcat -tb C:\Users\Andre\Pictures\aaa\E-W-45_1_1.ppm
>
> In both cases all I get has output can be seen in attachment, but no
> assembled image is produced. What am I doing wrong?


unfortunately the help page doesn't note that it sends the image to
stdout. what you're seeing is what you'd see if you tried to open the
image in a text editor.

NAME
       pnmcat - concatenate portable anymaps

SYNOPSIS
       pnmcat [-white|-black] -leftright|-lr [-jtop|-jbottom] pnmfile pnmfile ...
       pnmcat [-white|-black] -topbottom|-tb [-jleft|-jright] pnmfile pnmfile ...



so to use it you have to use ">" redirections. for example:

  pnmcat -lr img11.ppm img12.ppm img13.ppm img14.ppm > row1.ppm
  pnmcat -lr img21.ppm img22.ppm img23.ppm img24.ppm > row2.ppm
  pnmcat -lr img31.ppm img32.ppm img33.ppm img34.ppm > row2.ppm
  pnmcat -tb row1.ppm row2.ppm row3.ppm > final_image.ppm
  pnmtopng final_image.ppm > final_image.png