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List:       kde-commits
Subject:    extragear/graphics/doc/digikam
From:       Laurent Espitallier <laurent.espitallier () laposte ! net>
Date:       2010-02-28 23:05:30
Message-ID: 1267398330.618265.16660.nullmailer () svn ! kde ! org
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SVN commit 1097343 by lespitallier:

PGF format support (minor corrections)

 M  +2 -1      file-formats.docbook  
 M  +1 -1      index.docbook  


--- trunk/extragear/graphics/doc/digikam/file-formats.docbook #1097342:1097343
@@ -63,7 +63,8 @@
             </sect3>
 
             <sect3>            <title>PGF</title>
-	    <para> "Progressive Graphics File" is another not so known but open file image \
format. Wavelet-based, it allows lossless and lossy data compression. PGF compares \
well with JPEG 2000 but it was developed for speed (compression/decompression) rather \
than to be the best at compression ratio. At the same file size a PGF file looks \
significantly better than a JPEG one, while remaining very good at progressive \
display too. Thus, it should be well-suited to the web.  For more information about \
the PGF format see the <ulink url="http://www.libpgf.org/">PGF homepage</ulink>. +	   \
<para> +                "Progressive Graphics File" is another not so known but open \
file image format. Wavelet-based, it allows lossless and lossy data compression. PGF \
compares well with JPEG 2000 but it was developed for speed \
(compression/decompression) rather than to be the best at compression ratio. At the \
same file size a PGF file looks significantly better than a JPEG one, while remaining \
very good at progressive display too. Thus it should be well-suited to the web but at \
the moment few browsers can display it. For more information about the PGF format see \
the <ulink url="http://www.libpgf.org/">libPGF homepage</ulink>.  </para> 
 
             </sect3>
--- trunk/extragear/graphics/doc/digikam/index.docbook #1097342:1097343
@@ -1471,7 +1471,7 @@
 	<para><command>GIF</command> is a proprietary. patented format and slowly \
disappearing from the market. Don't use it.</para>  <para><command>PNG</command> has \
been invented as a Open Source standard to replace GIF, but it does much more. It is \
lossless, supports XMP, EXIF and IPTC metadata, 16 bit color encoding and full \
transparency. PNG can store gamma and chromaticity data for improved color matching \
on heterogeneous platforms. Its drawback are a relatively big footprints (but smaller \
than TIFF) and slow compression. We recommend it.</para>  \
<para><command>TIFF</command> has been widely accepted as an image format. TIFF can \
exist in uncompressed form or in a container using a lossless compression algorithm \
(Deflate). It maintains high image quality but at the expense of much larger file \
sizes. Some cameras let you save your images in this format. The problem is that the \
format has been altered by so many people that there are now 50 or more flavors and \
                not all are recognizable by all applications.</para>
-	<para><command>PGF</command> "Progressive Graphics File" is another not so known \
but open file image format. Wavelet-based, it allows lossless and lossy data \
compression. PGF compares well with JPEG 2000 but it was developed for speed \
(compression/decompression) rather than to be the best at compression ratio. At the \
same file size a PGF file looks significantly better than a JPEG one, while remaining \
very good at progressive display too. Thus, it should be well-suited to the web. For \
more information about the PGF format see the <ulink url="http://www.libpgf.org/">PGF \
homepage</ulink>.</para>  +	<para><command>PGF</command> "Progressive Graphics File" \
is another not so known but open file image format. Wavelet-based, it allows lossless \
and lossy data compression. PGF compares well with JPEG 2000 but it was developed for \
speed (compression/decompression) rather than to be the best at compression ratio. At \
the same file size a PGF file looks significantly better than a JPEG one, while \
remaining very good at progressive display too. Thus it should be well-suited to the \
web but at the moment few browsers can display it. For more information about the PGF \
format see the <ulink url="http://www.libpgf.org/">libPGF homepage</ulink>.</para>  \
<para><command>RAW</command> format. Some, typically more expensive, cameras support \
RAW format shooting. The RAW format is not really an image standard at all, it is a \
container format which is different for every brand and camera model. RAW format \
images contain minimally processed data from the image sensor of a digital camera or \
image scanner. Raw image files are sometimes called digital negatives, as they \
fulfill the same role as film negatives in traditional chemical photography: that is, \
the negative is not directly usable as an image, but has all of the information \
needed to create an image. Storing photographs in a camera's RAW format provides for \
higher dynamic range and allows you to alter settings, such as white balance, after \
the photograph has been taken. Most professional photographers use RAW format, \
because it offers them maximum flexibility. The downside is that RAW image files can \
be very large indeed.</para>  <para>My recommendation is clearly to <command>abstain \
from archiving in RAW format</command> (as opposed to shooting in RAW format, which I \
recommend). It has all bad ingredients: many varieties and proprietary nature. It is \
clear that in a few years time you cannot use your old RAW files anymore. I have \
already seen people changing camera, losing their color profiles and having great \
difficulty to treat their old RAW files correctly. Better change to DNG \
format!</para>  <para><command>DNG</command> Digital Negative file format is a \
royalty free and open RAW image format designed by Adobe Systems. DNG was a response \
to demand for a unifying camera raw file format. It is based on the TIFF/EP format, \
and mandates use of metadata. A handful of camera manufacturers have adopted DNG \
already, let's hope that the main contenders Canon and Nikon will use it one \
day.</para>


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