> does gimp compress photo's with one click?
Well... Err... Right-Click, File, Save-As. :^) So three clicks.
(Or bind 'Save As' to a key combo, like Sh+Ct+S)
> if not can anyone show me best way to compress my photos using gimp as its
> already installed into my machine
> i am using redhat 8
It really depends on what kind of files you're talking about.
I'll assume you're talking JPEG, and if so, then yes; it's got a little
"Quality" gauge you can alter when saving a JPEG file.
You may also want to look into either ImageMagick or NetPBM
(err, rather "cjpeg"/"djpeg"), as they should let you "load and re-save"
a JPEG file with higher compression (aka lower quality).
For example, using the cjpeg and djpeg tools:
djpeg IN.jpg | cjpeg -quality 50 > OUT.jpg
You could write a batch file that does this quality-reduction to your
entire collection of photos.
Note: Since JPEG is a lossy format, loading the JPEG up and then resaving it
will introduce extra "noise." (If you were to load and resave one over and
over again, it'd degenerate, like an Nth generation videotape copy!)
If you have originals of your photos in either some non-lossy format
(PNG, TIFF, TGA, etc.) or a larger resolution (e.g., 1600x1200 JPEG off
of your digital camera, but you're saving 400x300 images for the web),
you'd probably want to redo the conversion and/or size reduction, and
set the compression level when creating the final JPEG.
For example, with NetPBM tools:
tifftopnm IN.tiff | pnmscale .25 | cjpeg -quality 50 > OUT.jpg
... to convert an original, huge TIFF, reduce it down to 1/16th size,
and save it out as a 50% quality JPEG.
This is much better than:
tifftopnm IN.tiff | pnmscale .25 | cjpeg > FIRST.jpg
... then later on:
djpeg FIRST.jpg | cjpeg -quality 50 > SECOND.jpg
Because even though you didn't alter the quality settings when creating
FIRST.jpg, there are already artifacts there that will only be made worse
when re-JPEG'ing it into SECOND.jpg. It's just how the JPEG format works! :^)
Wow, have I rambled on enough?
(running on 0 sleep ;^) )