[Scribus] Image frame doesn't make any sense to me

[Craig Ringer]

dax702 wrote:

[re-ordered quote]
>  It would be as simple as "Size frame to
> dimensions of image"  You check the box, and when I click get picture, it
> takes those dimensions and plops the image on the page with a picture frame
> around the image, just like we do it for the web.

OK, so we're talking a minor UI tweak to save a step in the process?
Instead of:

- Draw frame
- Get picture
- Click OK
- Right click & resize frame to image

you want:

- Draw frame
- Get picture
- check "resize frame to image" checkbox
- Click OK

?

If not, then clearly something is not working how it should with your
source images (quite possibly a bug with EPS bounding box handling).


[re-ordered quote]
> Again, the adjust frame to image does not work as you would expect it
> to, it only adjusts the frame to the image size that's on the
> page already, but since you have to first define a frame size, if
> it's not right (in the sense that it's not the exact size as the
> image I'm placing into it), then adjusting the frame to the image
> doesn't work.  This is simply because the image wasn't placed on
> the page correctly to begin with...

Really?

Have a look at:
http://www.postnewspapers.com.au/~craig/scribus_image_sizes.png

I created an image frame, then copied it and placed the copy below the
first one. I imported an image into each. The pixel data in each frame
is the *same* - a 420x300 TIFF. The top one has the resolution hint in
the TIFF set to 72dpi, resulting in an ~150mm wide image. The other has
it set to 600dpi, resulting in a roughly 17mm wide image. You'll note
that Scribus has honoured those physical dimensions hints and placed the
images in the frames accordingly. The top frame is too small, so the
image extends beyond it to the bottom & right and will be cropped.

I then copied both frames and placed the copied to the right of the
originals. On each, I used "resize frame to image". The top one expanded
to fit the image according to the hinting information in the file, and
the bottom one snapped around the smaller image. Remember, these images
have the *same* pixels, they just have different suggestions to display
apps embedded in them. That's what you change when you set an image's
resolution or physical size in a bitmap editor without resampling the image.

All this behaviour is exactly as I'd expect, and exactly as I'd want.

If what you're observing isn't the same, then maybe it's related to your
use of EPS files as inputs. It could be that:

- The app writing the file sets the bounding box incorrectly;
- Scribus reads the bounding box incorrectly; or
- Scribus fails to honour the bounding box for EPS files.

If any of the above are the case then many of your concerns become
easily understandable. For testing purposes only, try rasterising your
image and importing it as a TIFF, just to see what happens. If the
behaviour is different you've quite probably hit a bug and it needs to
be looked into.

[re-ordered quote]
> I too am targeting real physical output, a book that people will buy.  For my
> situation, having the ability to plop these musical notation references on
> the page *exactly as they were created* is a significant drawback.  While
> you can certainly take a picture of grandma's birthday party and stretch it
> some, mess up the aspect ratio a little and it will still look fine,
> something like this music notation is immediately crap if it's not exactly
> as it was created..

Yes, bitmaps of vector artwork do introduce additional problems. Ideally
you just don't use them and work with the vectors instead, but you've
hit technical limitations in Scribus there I understand.

The trouble is that printers don't actually print bitmaps. There's no
exact translation from a bitmap to a part of a printed page. Some clever
halftoning is done by the printer to approximate the detailed
colour/density information provided by the bitmap, but it's still only
approximate. You can't magnify it to see the original pixels.

In general, you'll see fewer artifacts on bitmaps of line art when the
bitmap has been placed so that its resolution (actually ppi not dpi) is
one of a few multiples of the printer's dpi. Exactly how to arrange this
depends on your print technology and specific print device due to
specifics in halftoning behavior - maybe Louis can explain more? . In
any case, it's not as simple as it sounds to just place the image
"exactly as it was created".

Also, note that I never mentioned playing with the aspect ratio. That's
undesirable in most cases (though actually surprisingly OK within small
tolerances) and you'd never want to do it for bitmaps of line art. I'm
not talking about "grandma's birthday party" - I work for a newspaper,
and I'm talking about real work that has to come out looking _good_.

> I understand if one is putting a magazine or book together that has small
> pictures that have to be placed in a column or something like that, then
> yes, the image frame is a good tool for exact positioning and putting a very
> large huge pixel picture into a small box.

Honestly, it's more general than that. I think you've probably hit on
one of the few cases where frame-based image work *isn't* the better
approach.


> If I'm not the last person to use Scribus for assembling this type of book
> with music notation references, I can guarantee you will hear from others
> complaining that they can't accurately insert their bitmap images of music
> on the page.  All I'm suggesting is that the option should exist for cases
> where it makes more sense.

It does - "resize frame to image".

I'm not sure how else your needs could be met.


--
Craig Ringer