[Kde-imaging] Exif data

[Caulier Gilles]

Le Mercredi 27 Septembre 2006 06:56 PM, Neil Winchurst a écrit :
> Caulier Gilles wrote:
> > Le Mardi 26 Septembre 2006 19:47, Neil Winchurst a écrit :
> >> Caulier Gilles wrote:
> >>> Le Mardi 26 Septembre 2006 19:02, Neil Winchurst a écrit :
> >>>> Hi there,
> >>>>
> >>>> in a recent email this appeared.
> >>>>
> >>>>
> >>>> Second points, is about metadata an pictures format : not all file
> >>>> formats support metadata ! Exif (the most important format used in
> >>>> photography) is supported by TIFF, JPEG, and PNG only, but not by TGA,
> >>>> BMP, JPEG2000, EXR, GIMP, etc.
> >>>>
> >>>> Well when I change my photo files in Digikam from JPG to PNG I lose
> >>>> all the exif data. If I leave the files as JPG then the exif data is
> >>>> kept. So why don't my png files keep the data as mentioned above?
> >>>
> >>> witch digikam release you use ?
> >>>
> >>> Gilles
> >>
> >> Version 0.8.0.
> >
> > digiKam 0.8.x use libkexif/libexif to manage metadata. These library are
> > very limited (to manage only JPEG files) and are now obsolete.
> >
> > In current timplementation of digiKam (0.9.0-beta2), we using Exiv2
> > library instead. This one can drive JPEG, TIFF, PNG and RAW files formats
> > to extract EXIF, Makernotes, GPS, and IPTC metadata.
> >
> > Actually, Exiv2 can only write meatadat in JPEG, but for the next
> > release, PNG, and TIFF (and certainly RAW files) will be availabale in
> > write access.
> >
> > I'm sure about that : i'm also a developper from Exiv2 project. I will
> > implemente the writting access to PNG files.
> >
> > In digiKam 0.9.0, if you convert a JPEG file to a PNG file, you will see
> > the Exif, Makernote, GPS, and IPTC metadata on the right side bar like
> > you can see in these screenshots :
> >
> > http://digikam3rdparty.free.fr/Screenshots/PNGsupportindigiKam1.png
> > http://digikam3rdparty.free.fr/Screenshots/PNGsupportindigiKam2.png
> > http://digikam3rdparty.free.fr/Screenshots/PNGsupportindigiKam3.png
> > http://digikam3rdparty.free.fr/Screenshots/PNGsupportindigiKam4.png
> >
> > Also, in digikam camera interface, there is a new option to convert on
> > the fly all JPEG image to PNG without lost metadata during downloading.
> >
> > In fact, PNG support Exif, IPTC, and XMP to store metadata informations
> > like a byte array in a text chunk. This way is used by
> > ImageMagick/GraphicsMagick and Exiftools programs ! Try these command
> > line for example :
> >
> > #convert foo.jpg foo.png
> > #convert foo.png foo2.jpg
> >
> > If foo.jpg has Exif and iptc metadata, foo2.jpg will has too !
> >
> > Note : in the future, we have planed to add XMP support into Exiv2
> > library. Like this all major metadata used in photography will be
> > supported in digiKam and kipi-plugins.
> >
> > To resume : if you wantto see you Exif data from png file, try digikam
> > 0.9.0-beta2 (http://www.digikam.org/?q=download)
> >
> > Gilles Caulier
>
> Thanks for all that. I will stay with version 0.8.0 until version 9.0
> final is ready. I will not risk the beta versions. Apart from the Exif
> problem my current version is working well. Also I have seen all the
> emails about problems with the beta version!!
>
> Will the stable version 9.0 be ready soon?
>

Planed at december.

Gilles