Image duotone (Project)

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early draft

13:53 < SimAV> hello fschmid 
13:54 < SimAV> #3743 is appointed to you? I have stumbled over this bug yesterday and somehow need to have 
               a fix or workaround next week...
13:54 <@mrscribe> Colorize converts Spot colors to CMYK
13:55 < SimAV> "But
13:55 < SimAV> in general creating a doutone image with a spotcolour could be easily added, this
13:55 < SimAV> needs to disable the other colorfilters for this image. "
13:55 < SimAV> yes, that's what i have to do... 
13:57 < SimAV> it hasn't to be perfect yet, I just have to get out PDFs with duotone (black and a HKS color) 
               or grayscale images, no other types of images will be required...
14:00 < SimAV> I had already a look at scimage.cpp but as i don't know scribus internals i have no clue how 
               to let colorize and duotone output non-CMYK/RGB colors
14:01 < SimAV> is there some documentation available on how sccolor is used for a color consisting of a spot 
               color at 50%?
14:01 < SimAV> or just a spot color at 100%?
14:06 < fschmid> hmm, this is difficult as images are always represented as RGB or CMYK or Lab data in the 
                 pdf
14:06 < fschmid> there is no way to "colorize" a bitmap with a spotcolor in pdf
14:07 < fschmid> thats why the bug 3743 is still open
14:14 < SimAV> ok, but scribus is said to support duotone eps...
14:14 < SimAV> so a workaround would be to use a duotone eps if one can produce one?
15:23 < cezaryece> SimAV:  can you get duotone image saved as EPS file? I think it may best way to insert 
                   such image into PDF (by embedding EPS in PDF) and get it will works in print house
15:28 < SimAV> cezaryece, ah, one has to embed the EPS?
15:28 < SimAV> that might be why i can't find HKS in the exported eps/pdfs anymore :D
15:30 < SimAV> cezaryece, well, doesn't seem to work either?
15:30 < SimAV> Or is the EPS being compressed when it is embedded into the PDF?
15:30 < cezaryece> SimAV: how do you check this so fast?
15:31 < SimAV> grepping for HKS in the pdf
15:31 < SimAV> this doesn't work of course if the eps is being compressed 
15:31 < cezaryece> SimAV: if set compression in PDF embedded will be compressed also
15:31 < cezaryece> embedded EPS...
15:32 < SimAV> http://fpaste.org/nf6o/
15:32 <@mrscribe> Title: Viewing Paste #77830 (at fpaste.org)
15:32 < SimAV> that's the beginning of the eps that has been used
15:33 < cezaryece> ok, and now when you embed this EPS in PDF this postscript code should appear in PDF 
                   code, but it may be compressed
15:35 < SimAV> ok, grepping doesn't show the EPS code
15:35 < SimAV> even though i unchecked compress images
15:42 < cezaryece> SimAV: now I am finish working day, tomorrow I can check this issue with duotones from 
                   CorelDRAW
15:42 < SimAV> ok...
15:43 < SimAV> tomorrow i will be on the train all afternoon long
15:43 < SimAV> but i might be back tomorrow in 3-4 hours 
15:43 < a_l_e> SimAV: you may have to specify when your tomorrow starts :-)
15:43 < cezaryece> lol
15:44 < SimAV> a_l_e, atm i have 15.44
15:44 < SimAV> but tomorrow at the same time i won't be here
15:44 < a_l_e> ok, we're all at CET, then :-)
15:44 < SimAV> but tomorrow 3-4 hours "after the same time" ;)
15:44 < SimAV> probably :)
15:44 < cezaryece> ok, we have same time, so morning will be morning for us
15:45 < SimAV> when reading some scribus code i got the impression that it's mainly written by german spoken 
               people ;)
15:46 < a_l_e> scribus has been started by a german speaking person!
15:46 < SimAV> or at least several variables I saw have german names...
15:46 < a_l_e> and most variables had german names... nowadays, there should only be few of them left
15:47 -!- mizmo [~duffy@fedora/mizmo] has joined #scribus
15:51 < cezaryece> SimAV: what vector program you have? Illustrator, CorelDraw?
15:51 < SimAV> only FOSS software
15:52 < cezaryece> and PhotoShop...;)
15:52 < SimAV> but i got a EPS that was created by Photoshop (CS5)
15:52 < SimAV> no, i don't
15:52 < cezaryece> I see
15:53 < SimAV> but someone did me a favor and converted a testimage into a "duotone"
15:53 < SimAV> however, i have to do that for several images...
15:53 < SimAV> my first try was to use gimp, but there the plugins only simulate duotone and produce a RGB 
               image
15:54 < SimAV> then i thought about writing a small programm producing a 2-layer Tiff
15:54 < SimAV> using libtiff
15:54 < SimAV> but then i found out that scribus has an image effect called Duplex/Duotone
15:54 < SimAV> that ought to do just what i want, however it works only in CMYK and RGB and not using spot 
               colors
15:55 -!- pAt_ [~pat@pD9E0A821.dip.t-dialin.net] has quit [Quit: leaving]
15:55 < SimAV> they get converted to CMYK internally and the resulting image is a CMYK one
15:55 < a_l_e> ... which makes it almost useless...
15:55 < SimAV> absolutely
15:55 < SimAV> then someone told me yesterday, that scribus should have good support of duotone eps/psd
15:56 < SimAV> but until now all tries getting out a PDF that contains only black and my spot color failed
15:56 -!- Huhtiranta [~simo@dsl-lprbrasgw1-fe80dc00-50.dhcp.inet.fi] has joined #scribus
15:56 < SimAV> even when putting just one imageframe on a page
15:56 < SimAV> and importing the EPS that obviously consists just of black and spotcolor (checked with vim)
15:58 < a_l_e> somebody also told you that it may or may not work... you have to try :-)
15:58 -!- wolfspraul [~wolfsprau@mimi.q-ag.de] has quit [Quit: leaving]
15:58 < SimAV> now someone told me that PDF doesn't support spot colors in bitmaps which is the cause for 
               colorize not to work
15:58 < a_l_e> well, for the eps, you may have to check the experimental "eps embedding"... did you do it?
15:58 < SimAV> which i can believe, as photoshop refuses to export the duotone to tiff or similar
15:59 < SimAV> a_l_e, yes, i did, but still don't see the HKS in the PDF source code
16:00 < SimAV> and in the print preview the image is converted to CMYK
16:00 < a_l_e> the print preview goes through ghostscript... that does not count...
16:00 < a_l_e> pdf is native in scribus...
16:01 < a_l_e> you may try with another simpler eps and see how that one gets embedded...
16:02 < cezaryece> for HKS text is in PDF created from Scribus with EPS embedded with duotone image
16:02 -!- cezaryece [~quassel@83.2.27.2] has quit [Remote host closed the connection]
16:02 < SimAV> http://fpaste.org/Qg1m/
16:02 <@mrscribe> Title: Viewing Paste #77841 (at fpaste.org)
16:03 < SimAV> that's what i find in the PDF that contains just an image frame and the duotone EPS from PS
16:04 < SimAV>  /DeviceCMYK sounds very bad, i guess it should be /DeviceN in order to have a real duotone
16:04 < a_l_e> i would first try with a "normal" small eps with just a vector line in it and see if you get 
               the code from the eps in the pdf...
16:04 < a_l_e> and if it's there, i would check a very simple bitmap eps (no duotone or such)...
16:04 < a_l_e> no time to do it myself now, though...
16:05 -!- ludo21 [~lchevalie@lns-bzn-48f-62-147-222-239.adsl.proxad.net] has joined #scribus
16:05 < SimAV> ok... I'll try :)
16:06 < SimAV> ok, producing a EPS containing just a black and a HKS 15 rectangle works in so far as it 
               outputs something containing HKS 15 as %%DocumentCustomColors:
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16:08 -!- ludo2 [~lchevalie@lns-bzn-48f-62-147-222-239.adsl.proxad.net] has quit [Ping timeout: 276 seconds]
16:10 < SimAV> ok, when using a 2 rectangle EPS (black + HKS) 
16:10 < SimAV> (created by scribus)
16:11 < SimAV> then importing it in scribus again inside an image frame
16:11 < SimAV> saving the imageframe as EPS conserves the spot color
16:12 < SimAV> when saving the page containing the EPS as PDF without compression the EPS gets split up
16:13 < SimAV> but the PDF contains a line saying [ /Separation /HKS#2043#20K /DeviceCMYK 14 0 R] which 
               should be evidence enough to assume that everything worked as expected
16:13 < SimAV> well, this time i used HKS 43 instead of HKS 15, so that's no problem
16:16 < SimAV> but when using the EPS created by photoshop i can't find "HKS" anymore in the resulting PDF
16:27 < a_l_e> and you told scribus not to compress the bitmaps...
16:28 < SimAV> yes
16:28 < SimAV> ok, very interesting: when using "epstool --bitmap --device tiffsep foo.eps bar" the scribus 
               2-rectangle EPS gets correctly seperated, however the Photoshop EPS doesnt?!
16:35 < a_l_e> but the rectangles are vectors, aren't they?
16:38 < SimAV> yes
16:39  * SimAV wonders whether writing a program that writes millions of EPS rectangles to simulate pixels 
          would be worth being written :D
16:39 < SimAV> I guess the resulting PDF will be rather huge and extremely slow to open/print ;)
16:40 < SimAV> s/writing//g
16:41 < SimAV> well, i doubt that InDesign would do that
16:43 < SimAV> PDF must somehow support duotone images, but how?
16:50 < SimAV> hm, ghostscript seems to support psd as output format with spot colors
16:51 < SimAV> so the question is, whether scribus supports duotone psds... :D
16:51 < SimAV> (and then produces PDFs containing the spot colors and not their cymk representations)
16:58 < a_l_e> SimAV: once you have all the information, the best thing is probably to post a summary to the 
               scribus-dev mailing list...
16:59 < SimAV> :D
16:59 < SimAV> well, it would be good to know whether scribus supports duotone PSDs ;)
17:00 < SimAV> .oO(posting that information to the scribus-dev mailinglist sounds like carrying coals to 
               Newcastle)
17:01 < a_l_e> the question is whether the people who can answer the question are reading your words now...
17:02 < SimAV> yes...
17:02 < a_l_e> probably yes... but, to be sure, you'd better do a post to the ml
17:02 < a_l_e> it's also a chance to summarize all the information which has been written in the last hour...