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Problems with re-sizing images. - Printable Version

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Problems with re-sizing images. - menglor - 11-20-2017

Good Day!
 
I am a newbie learner to “” and I am trying to accomplish a series of steps, but things just don’t seem to work out for me.
 
I have 2 problems, well more but I wont go into everything J
 
-         Basically   I am trying to import a picture of varing sizes, and then resize them to fit a specific size.
 
For example,  I am importing an image  that is 5” x 3”,   and wanting to print it on a label, 
So I need to be able to copy it out of GIMP, and past it into a Avery Shipping Label template in Word.
 
I have been a little successful, but I am having issues with the sizes changing.
 
Steps I am completing.
 
1-     Open Image.
2-     Click menu “Image”  and then click Scale image
3-     I assign the Size height as  1.30 inches  (because of the linked reference, width defaults to  2.0 inches ISH  
4-     Resolution seems to imply its  76 x 76
5-     And it seems like it works, though when I COPY and paste into Word and print.  The size is a little off.
 
However, I went on to the next picture, which ultimately was a desktop  image ,  I completed the following
 
1-     Open Image.
2-     Click menu “Image”  and then click Scale image
3-     I assign the Size height as  1.30 inches  (because of the linked reference, width defaults to  2.0 inches ISH  
4-     Resolution seems to imply its  560 x 560  (don’t have the real numbers handy)
5-     Then I copy it , and then Paste into Word.
6-     When I look at the image in my template  the image height should be 1.3, but its about 2.3.  and the width is also messed up.
 
I am confused. If I tell them image to be 1.3  why is it not listening?   I understand there is a setting called Print size somewhere, but I am trying to make the image  Size X, but something else is getting in the way.
 
 
I am hoping someone can give me an answer,  or maybe point me to a Youtube video that goes over it.   I have watched about 6-8 tutorials, but I cant find anything that  goes into that whole aspect of


RE: Problems with re-sizing images. - Ofnuts - 11-20-2017

"Resolution" in DPI is meaningless until you print. Gimp works on pixels and what you copy/paste in Word are pixels, so the size in the final print should be set in Word (which will happily scale images, jut give an image at least as big as necessary for the bigger size with the best int definition you are targeting).


RE: Problems with re-sizing images. - menglor - 11-21-2017

forgive my ignorance, but I didnt understand a single thing your saying.. I am going to put together some pictures. maybe it will make sense?

I am sorry I dont speak the lingo, I have always learned by beating things into my head.  so when I look at what I have done, it makes sense,  but the output doenst.


so, I have opened a Jpg,  resized it down to 2.0 x 1.3 inches. and then the same thing to scale the layer. so my Screen on the PC has what your seeing in  PICK_One.jpg

note the in program ruler is showing a image size about 1.3 inches (plus or minus)

when I right click and COPY it, then PASTE over to Word,  it fills up the template (The Avery label template is 4 x 2 inches labels.)



I am at a loss to understand why.

now the part that Confuses me.

When I look at Pick_three,  its a Different Image.

but the ruler shows the same size.  1.3" x 2"

and when I paste it into Word.  its Much closer to the actual size when I print it.


see pictures  Three and Four


RE: Problems with re-sizing images. - Blighty - 11-21-2017

Gimp (and all bitmap editors) work in pixels, not in units like inches. If you specify a size in inches then Gimp does some behind the scenes work to convert to pixels. You need to understand the relation between image size, print size and dpi.

For example:

Image is 500 x 500 pixels.
Print resolution is 300 dpi
Print size is calculated to be 500/300 inches = 1.66 inches

Print size is 5 x 3 inches.
Prnt resolution is 100 dpi
Image size is calculated to be 5*100 x 3*100 = 500 x 300 pixels

You need 300 dpi for a good quality paper print.
So you can calculate the required image size in pixels.

You don't say what the original image sizes are in pixels. Are they good enough?

Scaling alters the image size in pixels. If you scale down pixels are thrown away so loose quality. If you scale up, pixels are created. Some algorithm will calculate what these created pixels are. So you also loose quality.

You need to scale some images to fit a Word template. Why not just let Word do the scaling. Then you don't need Gimp for this job.


RE: Problems with re-sizing images. - menglor - 11-21-2017

Thanks for the reply.
 
So because I am new at this, I am going to process this and try and play a bit. But I am still a bit on the confused side.
 
I never mentioned the DPI of the original picture, because in my particular case I don’t really know it.
 
Without going into too much detail,   I will say this:
-         I am taking pictures,  printing them to labels and then cutting up the pictures to fit the item I am placing them on.
 
The pictures will very in DPI depending were I collect the picture from,  the end product in this case is a 2.0 x 1.3 surface.
(varying in size from .8 x 4.0)
 
So far, because of the size I am shrinking down too, I haven’t needed to worry about DPI, since its so small, quality has only improved.
 
Also, because images might not fit the ratio’s I am going to put the label on, in a few cases, I have needed to stretch the canvas size, and add a colored background to so it doesn’t look stupid.  So pasting them into word isn’t really an option
 
So I guess what’s annoying me most about Gimp,  and I do understand what you’re saying about DPI
 
if I set the image canvas size to be  300 x 300 it’s the image is 300 x 300.  So in the SAME UI, I just change the dropdown to be inches instead of Pixels,  1.3 inches isn’t really 1.3 inches.
 
 
Maybe I am over thinking things and using the tool incorrectly.
So let me approach this question differently.
 
I am working with  Fixed Canvas size of   2.42 x 1.30 inches that when printed has to fit on that size of paper.
Knowing that I have  10 pictures of varying sizes and resolutions
 
How do I manipulate an image so that I don’t spend hours tweaking it?  
Copy each picture from Gimp, into my Avery label template
And print, so that the image size on the label measures 2.42 x 1.30 inches (even though the label measures  2 x 4 inches)
 
 
I accept the fact, that I am a total newb at this, and might have unreal expectations.  But then this is why I am asking you guys, because your clearly masters  at using these tools.
 
I really appreciate the time you guys spend on my problems, but even just to the community.


RE: Problems with re-sizing images. - Blighty - 11-21-2017

Try this:

Setup a *new* image as in the image below.

Set the Image Size to 4 x 2 inches
Set resolution to 300 dpi
Gimp will calculate the image size in pixels for you (1200 x 600 pixels)
(Remember Gimp works in pixels)
Call this layer Background.

(You can alter the Image Size in inches and/or the resolution. Gimp will recalculate the size in pixels.)

You will not use this Background layer directly. It is there to give an indication of size for your images.

Now Use (File > Open As Layers) to open one of your images. It will open as a new layer above the Background Layer.

Use the Scale Tool  or  (Layer > Scale Layer) to scale your image to the size of the Background layer.

When complete SAVE as a .xcf file (this preserves the layers) and EXPORT as .png. Use the .png file in Word.


RE: Problems with re-sizing images. - rich2005 - 11-21-2017

You must remember that Gimp works in pixels, not inches, metres, rods or microns.

See if you can follow the logic in the following. Too many screen shots for all in line and since I use linux it has to be LibreOffice (LO) rather than Word.

This is an avery template open in LO. The image is imported but as you see it is too large: https://i.imgur.com/lNJRFJk.jpg

I can resize that in LO, like this https://i.imgur.com/rpVcmpT.jpg


Somewhere there will be information on the size. If not measure it when printed https://i.imgur.com/soTROoi.jpg
That tells me I want something 0.85" https://i.imgur.com/soTROoi.jpg

Now into Gimp:
You say you do not know the pixel size. It will show at the top of the window (1)
Go into Image -> Print size and you get more details The Print size in various units (2)
The resolution of the image in pixels per inch (ppi) (3)

[Image: rIOgF3o.jpg]

You can change these values, I set the width and height to the size required for the label 0.85" (1)
Note how the resolution in ppi has changed but the size of the image in pixels remains the same. (2)

[Image: okaRmEU.jpg]

Now re-export that as a png or jpeg for the label.

Now when that new image with the print size is imported into the label it (should be) the correct size. https://i.imgur.com/R8bHb2e.jpg


RE: Problems with re-sizing images. - menglor - 11-21-2017

thanks guys

I will give both a try tonight and report on my findings.

I appreciate the help.  I understand what your saying that it works in pixels, but unfortunately. I am printing small items, and if its off by 3-4 pixels, its very noticeable.

Even more frustrating, it gets expensive as it uses up a sheet of labels that are not the right size. so they become scrap. and if I over size, I end up loosing parts of the picture.

To further add to my comments above.

When I say I do not know the pixel size,  I am saying each image is different, so I can find out the pixel size, but long term its going to change constantly. so ahead of time, I wont know the pixel size for any perticular image.

and for what I am doing, the size of what gets printed , is more important then the pixel count.

I need the print out to be 1.30 inches,  not 1.27 or 1.40.   I dont mind if its 1.27 because I can stretch it and paint in detail, but I would only learn the size after its printed and that is proving to be expensive over the long term.


RE: Problems with re-sizing images. - Blighty - 11-21-2017

(11-21-2017, 02:32 PM)menglor Wrote: I need the print out to be 1.30 inches,  not 1.27 or 1.40.

Another thing:
Printing to an exact is dependent on more than just Gimp. You also need to look at things like page setup in Word, settings in your printer driver (eg ignore margins), etc. There can be unwanted scaling in these.

Best to do your final scaling in Word.


RE: Problems with re-sizing images. - menglor - 11-22-2017

ok, so I just tried this again, and I really understand what your saying about the pixels vs inches, but its an issue

its not just about resizing the image. it has to arrive in word print ready.

So I did this as a Test, I said, I want a NEW image, 1" by 1" and 300 dpi (using Blightly's example)

I copied the image , and just pasted it into MS PAINT.

Now if I look at the image in GIMP, the ruler clearly shows 1 x 1. as you would expect. (at this point, I believe I am still dealing with a Raw image. not influenced by the printer.

however the ruler in MS Paint are claiming its 3 x 3. and really when I printed it from PAINT, it measured 3 x 3.

so, I dont know what to say.