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How to output exact image dimensions

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scantastik
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Joined: 23 Oct 2018, 08:01
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How to output exact image dimensions

Post by scantastik » 23 Oct 2018, 14:29

Using Scan Tailor Advanced, 1.0.16 Windows 64bit

Objective;
Original scans all: 2550 pixels wide x 3300 high , 300 dpi (US Letter 8.5 x 11 inch)
I wish to deskew only, and output exactly 2250 wide x 3300 high

I have tried many different settings combinations for margins and can't seem to achieve
an exact same dimension as I input.

Is this possible ?

If so, how.

Thank you.

zbgns
Posts: 33
Joined: 22 Dec 2016, 06:07
E-book readers owned: Tolino, Kindle
Number of books owned: 600
Country: Poland

Re: How to output exact image dimensions

Post by zbgns » 23 Oct 2018, 17:57

I guess, you may be interested in this how-to:
viewtopic.php?f=19&t=3495.

Another solution is to resize output images. E.g. XnView offer batch resizing of images.

I would probably use ImageMagick for that:

Code: Select all

mogrify -path resized/ -density 300 -units PixelsPerInch -resize 2550x3300! -compress lzw *.tif
(to avoid the original images are overwritten there must be indicated existing new directory where the 'path' parameter leads to).
Last edited by zbgns on 23 Oct 2018, 21:23, edited 1 time in total.

scantastik
Posts: 5
Joined: 23 Oct 2018, 08:01
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Country: USA

Re: How to output exact image dimensions

Post by scantastik » 23 Oct 2018, 20:05

Thank you, but your link is for gm (ghost script), not scantailor.

I am using the Scantailor Advanced GUI.
All source images are exactly US Letter, 300dpi, 2550x3300 (8.5 x 11 inches)

Which settings will produce a 2250x3300 300dpi output original size after an automatic deskew ?

Thank you.

Regards

zbgns
Posts: 33
Joined: 22 Dec 2016, 06:07
E-book readers owned: Tolino, Kindle
Number of books owned: 600
Country: Poland

Re: How to output exact image dimensions

Post by zbgns » 23 Oct 2018, 21:23

Well, the advice is about, how to output images that as exactly of dimensions you want to obtain after processing in Scan Tailor. Ghost Script is to create a template with proper dimensions.

You need to add one extra page fitting to the size. As your input pages have desired sizes, the workflow would be as follows:
1. load images
2. insert one image once again at the beginning or at the end; it must be exactly 2550x3300
3. deskew all images except this extra one
4. select contents of all images, however in case of the extra one there must be selected full page including margins
5. at the "margins" stage determine margins, however no one page may exceed 2550x3300 including margins (they may be smaller); the extra page must have margins set to 0.
6. At the "output" stage you probably need to set 300 DPI, "color/grayscale", no "equalize lumination", "filling color: Background".

After this all output pages should be exactly 2550x3300, 300 dpi, deskewed. You may delete the extra one page, as it was only the template and is not useful anymore.

The alternative method is to output pages not caring that much about dimensions and resize them in any external program that can do batch processing (and can insert DPI in metadata).

scantastik
Posts: 5
Joined: 23 Oct 2018, 08:01
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Country: USA

Re: How to output exact image dimensions

Post by scantastik » 23 Oct 2018, 22:03

Wow,

Thank you so much for taking the time to help me.
I'll follow your instructions.

By the way, if I choose method 2, can I determine what the pixel offset is
for planing alignment, or am I left with a simple crop to 2550 x 3300 ?

Thanks again.

Best regards.

zbgns
Posts: 33
Joined: 22 Dec 2016, 06:07
E-book readers owned: Tolino, Kindle
Number of books owned: 600
Country: Poland

Re: How to output exact image dimensions

Post by zbgns » 24 Oct 2018, 04:11

I meant rather simple stretching of images to the size you want. 'Squeezing" if there are too big or "distending" if there are too small. As there should be only slight difference in case of your output files, "resize" operation should give sufficient result: no visible geometry distortions or degradation of quality.

Cropping should be even better in your case. You set margins bigger than necessary and crop afterwards the extra parts.

scantastik
Posts: 5
Joined: 23 Oct 2018, 08:01
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Country: USA

Re: How to output exact image dimensions

Post by scantastik » 24 Oct 2018, 05:13

Hi again.

Step 4: Select Content;
I can't find enough documentation on this...
Which Settings should be set for my situation ? ;
a) Page Box = Disable/Auto/Manual' ???
b) Content Box = Disalbe/Auto/Manual ???

Step 5: Margins
For other pages, other than the 1st...
Which settings are appropriate to my situation ?
a) Auto Margins On/Off
b) Alignment Match size with other pages On/Off
c) Mode: Auto/Manual/Original
d) Do I include the extra page ?

Thanks again.

Regards

zbgns
Posts: 33
Joined: 22 Dec 2016, 06:07
E-book readers owned: Tolino, Kindle
Number of books owned: 600
Country: Poland

Re: How to output exact image dimensions

Post by zbgns » 24 Oct 2018, 07:57

Stage 4

Page Box disabled
Content Box auto. After this you need to check whether Scan Tailor chose properly contents on all pages. If any adjustments are necessary, do them manually. In the right hand bottom corner you have a box in which you may change order of pages. Change from 'natural order' to 'order by height'. Then go to the last page, check whether there are any wrongly recognized areas and correct this if necessary. Then navigate to the first page and do the same. After everything looks OK, change to 'order by width' and perform the same steps.

Stage 5

Auto Margins off
Match size with other pages On
Mode: Auto. After the processing is done you may do manual adjustments if necessary. You may change order of pages as described above to save a lot of time (no all pages must be checked, only the biggest and the smallest ones).
The extra page (the 'template') must be inserted at the earlier stage. It is too late to insert it at the 'Margins' stage.

scantastik
Posts: 5
Joined: 23 Oct 2018, 08:01
Number of books owned: 0
Country: USA

Re: How to output exact image dimensions

Post by scantastik » 25 Oct 2018, 08:56

Thanks for all your help zbgns.

Best regards.

[Solved]

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