On Friday 10 July 2009 05:00:58 pm Glenn Linderman wrote: > On approximately 6/29/2009 4:05 PM, came the following characters > from > > the keyboard of Ross Presser: > > In fact, the single image contained on the page is 2236x3025 > > pixels and 8.89"x12.1", giving a resolution of 250 dpi, not 300 > > dpi. > > > > ImageMagick won't know this, of course; I dug it out using > > Acrobat 9.0 Pro's measurement and preflight tools. > > Hmm. So if Acrobat 9.0 Pro can figure out the "native" dpi, why > can't other tools do it? I suppose it is "hard" or > "undocumented"? It seems that mostly it is Ghostscript that is > used to look at .ps and .pdf files... if it could learn how to > report on the dpi, it seems the world would be a better place.... > Guessing random dpi values until it "looks good" (and bigger dpi > values don't look "better") is a poor way of proceeding.... > > I suppose different images contained within a .pdf or .ps file > might have different resolutions. > > I'd like to know if there is a tool that exists that can do > either or both of the following: > > 1) extract embedded image characteristics from .ps and .pdf > files, so that an appropriate dpi setting can be used to convert > the whole file to raster. > > 2) extract the embedded images to .tif or .png format, retaining > the exact pixels, and setting the dpi to achieve the scale at > which it was embedded. > > Do tools like these exist? How much do they cost, or where can > they be obtained?
I sometimes import files into Gimp and do these kind of manipulations. The major manipulation occurs at the front end. If the PDF/PS file is in vector format then you can set a healthy dpi figure up front when you open it. Then the function image>scale image lets you do what you need. I just did that with a pdf created from a Gimp Manual html file. I set it at 600 dpi. Detail of the text is just fine even at magnified views. HTH -- John Culleton Create Book Covers with Scribus/e-book $5.95 http://www.booklocker.com/books/4055.html _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
