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Color profile problems while converting PDF to JPG
Posted: 2007-03-27T09:11:33-07:00
by pieter
Hi,
We have problems converting PDF to JPG inside PHP. Converting does work, but on a Linux server the output is a bad quality JPG. This is caused by the PDF (CMYK) input and JPEG (RGB) output. This needs to be translated with color profiles (sRGB and SWOP?). This works OK on our Windows server (good quality there), but it does not work on Linux: it produces the same bad quality output.
We use Ghostscript & IM, installed with the --with-lcms option (before that we got LCMS errors). I searched almost whole Google and forums for this issue, but without results. Has anyone expierience with this issue? Please advise...
Many thanks! Pieter
Re: Color profile problems while converting PDF to JPG
Posted: 2007-03-27T10:17:48-07:00
by magick
For quality conversion of a CMYK PDF to RGB JPEG, make sure you have a modern version of ImageMagick. The current release is 6.3.3-4. Next you have two methods for the colorspace conversion. Try this first:
- convert -density 300 -colorspace RGB image.pdf image.jpg
Next, ensure you have LCMS support with ImageMagick. Type
Make sure
-llcms is associated with the LIBS tag. If so, try this command:
- convert -density 300 image.pdf +profile '*' -profile USWebCoatedSWOP.icc -profile sRGB.icm image.jpg
Re: Color profile problems while converting PDF to JPG
Posted: 2007-03-27T10:46:21-07:00
by pieter
Thank you for you quick reply! I checked on your comments. Results are getting better, but still not full quality. Can we do better?
1) We use "ImageMagick 6.0.7 03/27/07 Q16". Is this version recent enough?
2) Yes, LCMS support is available:
Code: Select all
[b]identify -list configure[/b]
Path: /usr/lib/ImageMagick-6.0.7/config/configure.mgk
Name Value
-------------------------------------------------------------------------------
CC gcc
CFLAGS -O2 -g -march=i386 -mcpu=i686 -Wall -pthread
CONFIGURE ./configure --host=i686-redhat-linux-gnu --build=i686-redhat-linux-gnu --target=i386-redhat-linux --program-prefix= --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib --libexecdir=/usr/libexec --localstatedir=/var --sharedstatedir=/usr/com --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --with-perl --with-x --with-threads --with-magick_plus_plus --with-lcms
COPYRIGHT Copyright (C) 1999-2004 ImageMagick Studio LLC
CPPFLAGS -I/usr/include
CVS_BRANCH_TAG HEAD
CXX g++
CXXFLAGS -O2 -g -march=i386 -mcpu=i686 -pthread
DISTCHECK_CONFIG_FLAGS --host=i686-redhat-linux-gnu --build=i686-redhat-linux-gnu --target=i386-redhat-linux --program-prefix= --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib --libexecdir=/usr/libexec --localstatedir=/var --sharedstatedir=/usr/com --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --with-perl --with-x --with-threads --with-magick_plus_plus --with-lcms'CFLAGS=-O2 -g -march=i386 -mcpu=i686'
EXEC-PREFIX /usr
HOST i686-redhat-linux-gnu
LDFLAGS -L/usr/lib -lfreetype -lz
LIB_VERSION 0x607
LIB_VERSION_NUMBER 6,0,7,1
LIBS -lMagick [b]-llcms[/b] -ltiff -lfreetype -ljpeg -lpng -lbz2 -lz -lpthread -lm -lpthread
NAME ImageMagick
PREFIX /usr
QuantumDepth 16
RELEASE_DATE 03/27/07
VERSION 6.0.7
WEBSITE http://www.imagemagick.org
3) I tried this command:
Code: Select all
convert -density 300 /var/www/vhosts/drukkerijvanbarneveld.nl/httpdocs/test.pdf +profile '*' -profile /var/www/vhosts/drukkerijvanbarneveld.nl/httpdocs/Static/Images/UserUpload/USWebCoatedSWOP.icc -profile /var/www/vhosts/drukkerijvanbarneveld.nl/httpdocs/Static/Images/UserUpload/sRGB.icm /var/www/vhosts/drukkerijvanbarneveld.nl/httpdocs/out/image.jpg
Results are better than before, but unfortunately the output uses still bad coloring:
Original:
http://www.drukkerijvanbarneveld.nl/test.pdf
Output:
http://www.drukkerijvanbarneveld.nl/out/image.jpg
Please advise...
Many thanks, Pieter
Re: Color profile problems while converting PDF to JPG
Posted: 2007-03-27T12:19:20-07:00
by magick
You will need to define what "bad coloring" means to you. We checked the color conversion and it appears to be working fine-- that is the CMYK colors are correctly being converted to sRGB.
Re: Color profile problems while converting PDF to JPG
Posted: 2007-03-28T00:12:53-07:00
by pieter
Sorry, the quality loss was caused by the JPG compression. After adding -quality 100 to the convert command the quality improved. Thank you for your help!
Re: Color profile problems while converting PDF to JPG
Posted: 2007-11-23T14:27:15-07:00
by svirid
I had the same problem with our conversion tool.
What I did is, I started to call ghostscript instead of the image magic.
here is what solved my problem
gs -q -sDEVICE=jpeg -dSubsetFonts=true -dEmbedAllFonts=true -dUseCIEColor -sOutputFile=$this->destination -r200 -dBATCH -dNOPAUSE $this->sourceFile
