CompuServe Thread

#PageStream & Bitmaps

11 messages in this thread
#30390From: Software EtcJul 28, 1991 11:15 PM
I'm kinda confued as to hw PageStream 2.1 handles bitmap imports. I made a bit map logo using DpaintIII, when I import it into Pagestream 2.1 It fills nearly the whole screen. I use the edit coordinats requester to get it somewhere around the size I want (using the %height & width). Now when it prints out though it is rather blocky and pixelly. Is this an inherent problem with bitmaps or is there some way I can get smoother scalings and resizings OR get it to use the same size it was when I created it in DPAINTIII (if I print it from DPaintIII it looks acceptable) I'm kinda wondering this because the squirrel picture from the PageStream tutorial looks great when I printed out the tutorial picture. Any hints or information would be appreciated.
#30414From: Michael GerardJul 29, 1991 9:39 AM
Eric: You should pick up two other packages for working with your graphics. AdPro (or even TAD, for that matter) has an excellent scaling tool in addition to all of its other goodies (like color to greyscale, dithering patterns and on and on) ProDraw has a utility called TRACE which will turn your bitmaps into structured clips that can then be imported into ProDraw and saved as EPS images… bye bye jaggies. Anytime you change the size of a bitmap from within PageStream, you're going to get unpredictable results… moire patterns & jaggies, etc. Scale the image outside of PageStream to the size you need and then for dot matrix output, appply a halftone screen (if it's a bitmap greyscale) of something like 63 LPI. It takes some experimenting but you can get outstanding results. BTW, softLogic is due out, RSN, with a structured drawing program that is supposed to also have a TRACE type utility in it.
#30967From: Jim HalleyAug 4, 1991 12:25 AM
When is this program from SoftLogik due out? Jim H. – via Whap!
#31123From: Michael GerardAug 6, 1991 8:19 AM
You'd have to call SoftLogic for the release date on their structured drawing program, but all the notices I have seen have indicated "Real-Soon-Now" <g> – Whapping from the North Coast Michael
#31470From: Jim HalleyAug 10, 1991 10:05 PM
I guess I can probably wait for it, but I feel certain that I will probably get it. JH – via Whap!
#30439From: Michael GerardJul 29, 1991 4:22 PM
Eric: You should pick up two other packages for working with your graphics. AdPro (or even TAD, for that matter) has an excellent scaling tool in addition to all of its other goodies (like color to greyscale, dithering patterns and on and on) ProDraw has a utility called TRACE which will turn your bitmaps into structured clips that can then be imported into ProDraw and saved as EPS images… bye bye jaggies. Anytime you change the size of a bitmap from within PageStream, you're going to get unpredictable results… moire patterns & jaggies, etc. Scale the image outside of PageStream to the size you need and then for dot matrix output, appply a halftone screen (if it's a bitmap greyscale) of something like 63 LPI. It takes some experimenting but you can get outstanding results. BTW, softLogic is due out, RSN, with a structured drawing program that is supposed to also have a TRACE type utility in it. Hope this helps.. – Whapping from the North Coast Michael
#30454From: BILL LEACHJul 29, 1991 7:19 PM
I import iff files all the time and don't have a problem. The paint program that I use is Express Paint though and I suspect that the fact that Express Paint uses a 900K virtual page is the difference. A full screen image from DPaint would probably only amount to roughly a 9 square inch surface on a laser printer output. If you expand that to be a full page size in PGS then I would think it would be very blocky. If DPaintIII will work with "superbitmaps" you might still have a chance. You need something close to 2400 by 3200 pixels for a full page image. An Amiga message processed by Whap!, bill
#30458From: Paul GerhardtJul 29, 1991 7:44 PM
Craig, I am not SL tech support. But I may be able to help. Preparing a bitmapped graphic for printing within PgS or any other DTP program requires a little extra planning to obtain the best results. There are really two different cases that require two different strategies. First B&W line art. The ideal for line art is to have one pixel in your graphic for every pixel your printer will place on the paper. Now, for a 300dpi printer that's alot of pixels! A high rez (640 x 400) interlace image created in Dpaint will print out at a little over 2" wide by 1 1/3" high at 300dpi. The key here is to create really BIG graphics. When I scan at 300dpi I routinely produce images that are thousands of pixels wide by thousands of pixels high. Whether is is scanned or created by hand, work so that you have 300 pixels (for a 300dpi printer) on the screen for every inch that is to be printed. The second case is color or greyscale images. The default screen (<- printing term, not monitor screen) for 300 dpi printers used by PgS uses a block of 4 printer pixels by 4 printer pixels to represent one image pixel. This gives 17 levels of grey. Here the ideal would be 75 pixels (300/4) on the screen for every inch to be printed – which happens to be close to the dpi of a high rez interlace screen! Now, how to get your image into PgS? PageStream has the little known feature of letting you specify the size you wish the imported image to be in dpi (image dot per inch). When you import a graphic a requestor pops up. One of the text fields is labeled "As:" and has either window or object in it. Place the curser at the beginning of the field and type "dpi=300,300" (no quotes) to import your 300 dpi line art, or "dpi=75,75" for grey scale images. The words "object" or "window" will be push aside, but that's OK. When the graphics curser appears click down (not click and drag) and your image will imported at the specified resolution. Of course you can experiment with any resolution you [ MORE ]
#30459From: Paul GerhardtJul 29, 1991 7:45 PM
[ continuation ] would like. In practice I usually only use the dpi=300,300 for importing line art. I usually just click and drag ( holding down the shift key to maintain the aspect ratio) greyscale images to get them to the size I want. -Paul-
#30805From: Soft-Logik Tech SupportAug 2, 1991 2:19 AM
Paul: thanks for replying. You just saved me a lot of typing! The import dpi=xxx,yyy currently only works with a picture window. You can't import it as an object (or the dpi=xxx,yyy will get ignored.) This is a known bug. Why do we have to do this anyway? Because, when the IFF format was set out, nobody thought to add a resolution chunk. IMG has this and that makes it very handy. You don't have to remember that the picture is 72dpi or 300 dpi. It imports correctly the first time. The dpi=xxx,yyy lets you simulate this. If you don't specify this, when a non-resolution set bitmap is pasted into PageStream, it will map one dot to one pixel. That's why it's huge. Just shrink it down or shrink it while pasting it. BTW, it is possible to add a resolution chunk to an IFF file, but of course, nobody else will know it's there because it has to be a standard that everyone follows. SL Tech
#30829From: Paul GerhardtAug 2, 1991 9:51 AM
You are welcome. It is just the teacher in me. If I see someone with a lack of understanding, and I feel I can enlighten them, then off I go! The dpi=xxx,yyy bug you mentioned surprised me. If fact as I am writing this I loaded PgS 2.1 and gave it a try. I was able to change the import resolution of an object and it worked! I have had to change where I entered the "dpi=xxx.yyy" text string. In 2.0 I entered it in the "TYPE" string gadget. Now I find the "AS" gadget more reliable. I often use the "dpi=xxx,yyy" feature for scaling. If I scan at 200dpi and import at 300dpi that's a 33% reduction. If I scan at 400dpi and import at 300dpi then that's a 33% enlargement. Various combinations will let you change the size of an image while maintaining that one pixel per printer dot ideal. Very handy! BTW in your previous message you mentioned PgS 2.2. Now I don't want to bug you but. . . How's it going? Are we getting close? 🙂 -Paul-