[Digikam-devel] digikam PNG workflow...

[Caulier Gilles]

Le Lundi 23 Janvier 2006 20:46, Marcel Wiesweg a écrit :
> Am Montag 23 Januar 2006 12:31 schrieb Gilles Caulier:
> > Hi all,
> >
> > Please take a look in my new blog entry and let's me hear you
> > viewpoints...
> >
> > In Camera interface : add a new option to convert on the fly JPEG and RAW
> > files to PNG . Exif from RAW file can be get from THM (JPEG thumbnail)
> > file provides by camera. Put automaticly all JPEG metadata to dedicaced
> > PNG metadata tags.
>
> Would the lossless PNG be equivalent to the RAW file, or does a RAW file
> contain more data? If it does, people might want to keep a "digital
> negative" additionally to the "working copy" in form of the PNG.

Well RAW file formats are the big bazard. there is nothing homogenous and 
anyone includes metadata, anyone no. For more information about RAW files 
problems, take a look in openraw web site :

http://www.openraw.org/

In all cases, PNG is better than RAW, because :

- It's a GPL-iszed standard... better than DNG that there is no lib to manage 
it. It's an non-standard file format provide by a commercial compagny : Adobe 
(tm)
- It's can be displayed without problem by all web/file managers.
- It's can be decoded more speedly than RAW files (:=))).
- It's a RW file format, not RAW files.
- It's can be compressed like TIFF with a better ratio, and _LOSSLESS_ !
- It's can be read on all computers. There are no PNG patents...

Using libPNG is easy and ready to use now. I have just need to add any lines 
of code in png image loader to backup/extract JPEG metadata (:=)))

Gilles