On Fri, 2009-12-18 at 18:09 -0500, Jay Smith wrote: > I am afraid I am not 100% following what you are saying. Perhaps I > miscommunicated. Or perhaps I am just not filling in assumed knowledge > well enough. > > I want to use Gimp as an image editor.
Well, you say that you want to process thousands of images. Then GIMP is the wrong tool for the job. > b) I would like to find a method to remove color profile parasites on > thousands of images, via the command line. You have suggested trying > "tifftopnm | pnmtotiff" do to this. I will experiment with that, but I > have a concern as noted below. > > Based on your most recent recommendation, I looked at > http://netpbm.sourceforge.net/doc/tifftopnm.html > and I am not sure how this helps me, unless you are suggesting to > ROUNDTRIP using these two programs. But that is exactly the same thing that happens when you open a TIFF file in GIMP and save it again. The pixel data is loaded into GIMP and your file is not any longer a TIFF file then, it is a collection of pixels, let's call it an image. Then when you save it as TIFF again, this collection of pixels is encoded as a TIFF file. Pretty much exactly what tifftopnm | pnmtotiff is doind. > However, I noted it said [below] that theoretically you can lose > information in certain cases. I have no idea if my images would be > affected by that. > > "The PNM output has the same maxval as the Tiff input, except that if > the Tiff input is colormapped (which implies a maxval of 65535) the PNM > output has a maxval of 255. Though this may result in lost information, > such input images hardly ever actually have more color resolution than a > maxval of 255 provides and people often cannot deal with PNM files that > have maxval > 255. By contrast, a non-colormapped Tiff image that > doesn't need a maxval > 255 doesn't have a maxval > 255, so when > tifftopnm sees a non-colormapped maxval > 255, it takes it seriously and > produces a matching output maxval. Another exception is where the TIFF > maxval is greater than 65535, which is the maximum allowed by the Netpbm > formats. In that case, tifftopnm uses a maxval of 65535, and you lose > some information in the conversion." Since GIMP doesn't support a maxval > 255, you would more likely lose information if you used GIMP for this. Sven _______________________________________________ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
