2005.12.06 08:04 "Re: [Tiff] how to split layers in tiff file", by Kai-Uwe Behrmann

Am 05.12.05, 15:07 -0800 schrieb John Engelke:

There is information about a Photoshop-specific Image Source Data tag in the March 22, 2002, posting of Adobe Photoshop TIFF Technical Notes. ( http://partners.adobe.com/public/developer/en/tiff/TIFFphotoshop.pdf ) It states that the tag "37724" contains "the layer and mask information found in a typical layered Photoshop file". So that is where the information on photoshop layers, not channels, is contained.

Does anyone know of a TIFF processing library, command-line tool, API

Try tiffsplit. It comes with libtiff and lays in the tool directory.

or anything else that can deal with this Adobe tag. I know that Photoshop and GIMP deal with it, and I am just hoping for something

Grepping in the Gimp plug-in sources shows no support for this tag. The layer support is done without this infos provided by this specialised tag.

server side, libtiff or otherwise. I am sorry I would develop this myself but there is just no time, that is why I am seeking a mature library that can handle these things. Please help...

Did you search the libtiff email archive? I think this toppic was several times explained.

Look for something like: directory

The following code snippet should count the layers (IFDs) in a tiff file: while (TIFFReadDirectory (tif)) { count++; }

P.S. The handling of Photoshop layers would be a great addition to libtiff... (that is if I'm not mistaken by now that it can't handle this ...)

I did not see photoshop originated tiffs yet. Curious for an example. Can you provide one?

regards
Kai-Uwe Behrmann

                                + development for color management 
                                + imaging / panoramas
                                + email: ku.b@gmx.de
                                + http://www.behrmann.name

On 12/5/05, Brad Brock <brad_brock@yahoo.com> wrote:

In my last post, I mean layers in the context of Photoshop and GIMP. I really need a help in this topic. In fact, not only tiff file but also psd file, I think both of them are very similar. Please, any help would be great. Thank you.

Bob Friesenhahn <bfriesen@simple.dallas.tx.us> wrote: On Mon, 5 Dec 2005, John Engelke wrote:

Please any further information on this topic would be helpful. I have a Photoshop Tiff file with embedded layers that I need to either break out and recombine or simply delete, similar to the poster's issue. My issue is about layers as opposed to channels. I would think that since Photoshop is used in like 90+ percent of publishing operations around the world (defacto standard) that this issue would have been addressed. Any guidance whatsoever is appreciated.

As Joris says, TIFF has "channels" rather than "layers". However, extra channels can be used to implement "layers". For example, an associated alpha channel is called a "layer" by Photoshop.