mailing-list for TeXmacs Users

["Sam Liddicott" <address@hidden>]

All lies! qt_image_to_eps is not a qt function but a texmacs function - 
and further, it is responsible for the "colorimage" format I was so 
praising of on my 10.04 system.

However disabling use of qt_image_to_eps did stop the problems, so I 
only have a short code path to investigate to find the true cause.

Sam

On 12/05/11 16:38, Sam Liddicott wrote:
> The problem seems to be that since I re-build TeXmacs under Ubuntu 
> 11.04, qt_image_to_eps is being used to generate the eps in 
> image_to_eps() file image_files.cpp
>
> I disabled that particular function and now the "convert" program from 
> imagemagick is being used, so it is interesting to note that USE_GS is 
> not defined.
>
> Convert is better than QT and produces 158MB of .ps compared to gs's 
> 200MB and QT's 280MB
>
> This 158MB .ps shrinks down to 2.6MB
>
> So the culprit is qt_image_to_eps() on Ubuntu 11.04 doing something 
> too clever that results in enormous files which often render badly.
>
> I'm also willing to swear in a very general sort of way that I don't 
> think that -dPDFSETTINGS=/printer or -dPDFSETTINGS=/screen made any 
> difference to final pdf from the .ps generated with qt_image_to_eps() 
> - but when I take away qt_image_to_eps() the -dPDFSETTINGS makes a 
> difference to the size of the pdf and quality of embedded images.
>
> I propose quite strongly that qt_image_to_eps() not be used.
>
> Sam
>
>
> On 12/05/11 16:00, Sam Liddicott wrote:
> > With the help of this script running in my .TeXmacs/system/tmp folder:
> > while : ; do ln *eps x/ ; ls -l x ; sleep 0.1 ; done
> >
> > I've got a load of the .eps files.
> >
> > I note that the eps files fed to gs on Ubuntu 11.04 are usually 
> > larger than those fed to gs on 10.04, and have a different form.
> >
> > Those on 11.04 have the bitmap defined the with loads of lines like 
> > this:
> > 138 140 r5
> > 7420 5980 10 10 rf
> > 142 148 r5
> > 7430 5980 10 10 rf
> > 142 140 r5
> > 7440 5980 10 10 rf
> > 142 148 r5
> >
> > Those on 10.04 have the bitmap defined like this:
> > colorimage
> > [B?XWa2ZEF`...
> > ....
> >
> > which appears to be perhaps a based64 style encoding of the bitmap.
> >
> > That would account for the difference in size of eps, and why the .ps 
> > is 50% bigger, but does not directly explain how this should cause a 
> > 20x bigger PDF.
> > I don't know... maybe pstopdf recognized the "colorimage" form and 
> > optimised and jpeg'd it?
> >
> > Now I need to work out how/why texmacs gets the images emitted in 
> > different forms... anyone who knows should speak up now.
> >
> > Sam
> >
> > On 12/05/11 15:04, Sam Liddicott wrote:
> > > I copied the 279MB .ps file to an ubuntu 10.04 machine and ran 
> > > pstopdf and it produced a 42MB pdf as before so I don't think 
> > > pstopdf is to blame.
> > >
> > > I then copied over my .tm files (and my .TeXmacs dir) and exported 
> > > the ..ps and it came only to 99MB instead of 279MB - that's a big 
> > > difference.
> > > So TeXmacs on my Ubuntu 11.04 produces enormous .ps files
> > >
> > > I copied the 99MB .ps back to my 11.04 machine and ran ps2pdf and it 
> > > produces a 2.6MB .pdf file instead of a 42MB file.
> > >
> > > So I need to find out what texmacs does to export the .ps file to 
> > > see what it is behaving differently on ubuntu 11.04
> > > Anyone knows? Please tell!
> > >
> > > I'm using my own git based build of texmacs.
> > > On 10.04 I'm using TexMacs with top change vdhoeven Fri March 18th 
> > > "Fix"
> > > On 11.04 I'm using top change vdhoeven Apri 27
> > >
> > > I'll now rule that out as a difference, I'm building the version I 
> > > was using on 11.04. (My 11.04 was an upgrade from 10.10, not a 
> > > re-install so I don't think it's a case of different code paths 
> > > because of missing libs).
> > >
> > > I've reverted my TeXmacs and it makes no difference.
> > >
> > > I'm looking at the way TeXmacs invokes gs when exporting the .ps 
> > > file, it calls like this:
> > >
> > > gs -dQUIET -dNOPAUSE -dBATCH -dSAFER -sDEVICE=epswrite -dEPSCrop
> > >
> > > I guess for each of the image files I use. This must be producing 
> > > different files on Ubuntu 11.04
> > >
> > > Sam
> > >
> > >
> > >
> > > On 12/05/11 13:35, Sam Liddicott wrote:
> > > > Hmmmm... I tried viewing my PDF on windows in foxit pdf view and 
> > > > it's great!
> > > >
> > > > Evince under ubuntu is rubbish and shows all the half-tone style 
> > > > dithering and the rest.
> > > >
> > > > However I can't put all the blame there, I have a PDF of a document 
> > > > this one was derived from, using many of the same images and it 
> > > > still displays fine, and from the artifacts when zooming closely, 
> > > > must be using JPEG (and it's a much smaller file).
> > > >
> > > > So I'm guessing that the PS/PDF internal image format I'm now 
> > > > getting from TeXmacs is different such that
> > > > 1. images are larger
> > > > 2. when converted to pdf, display badly in evince pdf viewer (but 
> > > > as PS display fine).
> > > >
> > > > I don't have any record of how big the .ps files used to be.
> > > >
> > > > I'll try and find an ubuntu 10.10 machine I can run pstopdf on and 
> > > > see if that produces PDF of a normal size.
> > > >
> > > > Sam
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > On 12/05/11 11:53, Sam Liddicott wrote:
> > > > > On 11/05/11 19:39, Sam Liddicott wrote:
> > > > > > I have a 48 page TeXmacs document, and many of which have images 
> > > > > > which are screen-shots and so not very high resolution - I think 
> > > > > > all are less than 800 pixels wide.
> > > > > >
> > > > > > The png image source directory and .tm file come to under 9MB, 
> > > > > > and the document uses only about half of those images.
> > > > > >
> > > > > > The exported post-script is 280MB and the PDF is 40MB - which are 
> > > > > > horrific sizes.
> > > > > >
> > > > > > (I'm using latest git repository from 
> > > > > > git://gitorious.org/texmacs/texmacs.git)
> > > > > >
> > > > > > I tried compiling with --enable-pdf-renderer but then pdf export 
> > > > > > fails with:
> > > > > >
> > > > > >
> > > > > > ** WARNING ** Failed to load AGL file "pdfglyphlist.txt"...
> > > > > > ** WARNING ** Failed to load AGL file "glyphlist.txt"...
> > > > > > /home/sam/.TeXmacs/system/tmp/tmp_2009563087.pdf
> > > > > > /home/sam/.TeXmacs/system/tmp/tmp_514256944.pdf
> > > > > > ** ERROR ** TFM: Invalid TFM ID: -1
> > > > > >
> > > > > > Does anyone have any tips on reducing the PDF size? I tried 
> > > > > > changing from 600dpi to 300dpi but it only saved 2MB on the PDF
> > > > > >
> > > > > > I'm quite certain from the PDF view (where the screen shots are a 
> > > > > > bit washed out and have a funny interference pattern) that the 
> > > > > > images are being scaled up and even screened in some way, which 
> > > > > > is why the post script is so big.
> > > > >
> > > > > Changing the dpi for the printer settings affected the relative 
> > > > > size of the images in the document :-( so I had to change back.
> > > > >
> > > > > Further examination lays the blame with pstopdf, although I guess 
> > > > > a png decoder could have been embedded in the post-script which 
> > > > > would have kept the .ps file small - and myabe the PDF small too, 
> > > > > although I still have to investigate what the PDF is doing.
> > > > >
> > > > > This link talks about png decoders in post-script.
> > > > > http://www.tek-tips.com/viewthread.cfm?qid=1050035&page=7
> > > > >
> > > > > Here is a slice of one of my  images:
> > > > >   http://mail.liddicott.com/blotchy-2-orig.png
> > > > >
> > > > > It looks just as fine in the post-script view.
> > > > >
> > > > > And here is a screenshot from my PDF viewer at 400%
> > > > >   http://mail.liddicott.com/blotchy-2.png
> > > > >
> > > > > The areas of solid 24 bit colour have been dot-ified, some kind of 
> > > > > hatching or other dithering it seems.
> > > > >
> > > > > The change I observe may be different defaults for pstopdf as I 
> > > > > have just upgraded my ubuntu release.
> > > > >
> > > > > Sam


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