[Digikam-devel] extragear/graphics/digikam/libs/dimg/loaders

[Gilles Caulier]

Le Jeudi 29 Décembre 2005 18:29, Tom Albers a écrit :
> Op donderdag 29 december 2005 18:35, schreef Gilles Caulier:
> > Le Jeudi 29 Décembre 2005 18:16, Tom Albers a écrit :
> > > Op donderdag 29 december 2005 18:18, schreef Gilles Caulier:
> > > > Le Jeudi 29 Décembre 2005 17:09, Belinda Martin a écrit :
> > > > > On Thursday, 29. December 2005 14:39, Gilles Caulier wrote:
> > > > > > SVN commit 492272 by cgilles:
> > > > > >
> > > > > > digikam from trunk : using -q dcraw option to decode RAW file
> > > > > > under Image Editor is better than -h : right image size, good
> > > > > > image quality, and suitable image decoding speed. TODO : added
> > > > > > new IE setting tab in setup dialog about advanced RAW decoding
> > > > > > options. CCMAIL:
> > > > > > digikam-devel at kde.org
> > > > > >
> > > > > >
> > > > > >  M  +4 -4      rawloader.cpp
> > > > > >
> > > > > >
> > > > > > ---
> > > > > > trunk/extragear/graphics/digikam/libs/dimg/loaders/rawloader.cpp
> > > > > > #492271:492272 @@ -73,11 +73,11 @@
> > > > > >
> > > > > >      // run dcraw with options:
> > > > > >      // -c : write to stdout
> > > > > > -    // -h : Half-size color image (3x faster than -q)
> > > > > > +    // -q : Use simple bilinear interpolation for quick results
> > > > > >      // -2 : 8bit ppm output
> > > > > >      // -w : Use camera white balance, if possible
> > > > > >      // -a : Use automatic white balance
> > > > > > -    command  = "dcraw -c -h -2 -w -a ";
> > > > > > +    command  = "dcraw -c -q -2 -w -a ";
> > > > > >      command += QFile::encodeName( KProcess::quote( filePath ) );
> > > > > >
> > > > > >  #ifdef ENABLE_DEBUG_MESSAGES
> > > > > > @@ -156,11 +156,11 @@
> > > > > >
> > > > > >      // run dcraw with options:
> > > > > >      // -c : write to stdout
> > > > > > -    // -h : Half-size color image (3x faster than -q)
> > > > > > +    // -q : Use simple bilinear interpolation for quick results
> > > > > >      // -4 : 16bit ppm output
> > > > > >      // -a : Use automatic white balance
> > > > > >      // -w : Use camera white balance, if possible
> > > > > > -    command  = "dcraw -c -h -4 -w -a ";
> > > > > > +    command  = "dcraw -c -q -4 -w -a ";
> > > > >
> > > > > Salut Gilles,
> > > > > I have the dcraw version 7.94, it doesn't accept -q without a
> > > > > numerical parameter. It requires at least '-q 0' to work. Maybe you
> > > > > have an earlier version?
> > > > >
> > > > > Gerhard
> > > >
> > > > Right. I use dcraw v7.49 that don't have any numerical values to use
> > > > with -q option. From my dcraw man page :
> > > >
> > > > -q : Use simple bilinear interpolation for quick results. The default
> > > > is to use a slow, high-quality adaptive algorithm.
> > > >
> > > > Dave Coffin have broken command line compatibility. It will be cool
> > > > if he can use a default value with -q option with future dcraw
> > > > release.
> > >
> > > Since that version is already released, that is not a solution for now,
> > > right?
> >
> > well i have planed to add a new setup tab dedicaced to RAW decoding
> > options. Perhaps we can make a rules to control -q options depending of
> > dcraw version, but i think that this way is a little bit complicated for
> > end users.
> >
> > The better way is to finalize C++ dcraw port in libs/dcraw... but i have
> > no free time to complete it now.
>
> Maybe go back to -h by default then? But I should not interfere, I really
> dont know what im talking about.

Well, no (:=)). "-h" dcraw option is a way to extract Raw image data speedly. 
It's must be used by an image viewer, or to compute Raw thumbnail when there 
is no embeded thumb available.

My first implementation used -h option, and it's an error from me because we 
need the real Raw image size in image editor. If we use -h option, the size 
is reducing to improve speed raw decoding.

-q dcraw option is the right way. Raw image size is preserved. With last dcraw 
implementation, we can adjust decoding quality from 0 to 3 using this option. 
0 (low but good quality) can be used to slow computers, and 3 (very hight 
quality) on speed computer.

If i have no time to finalize c++ dcraw port in the next month, i will use the 
new dcraw -q option synthax and add a new setup for RAW file decoding in 
setup dialog. This is want mean that digikam depand of the last dcraw 
release, not the older ("-q 0" doesn't work with dcraw 7.49 on my computer) 
Note : there are any other options to add in this setup area to optimize RAW 
files decoding.
-- 
Gilles