Question for the book scanners

[Dave Britten]

I've got a few small books that I'm scanning by pressing them flat on my scanner. The results are pretty good, but of course I get two pages in a side-by-side format doing it this way. Are there any free/cheap tools that could largely automate the process of splitting the pages down the middle and turning them into two individual pages in the PDF? Ideally something that just lets me select a range of pages and click the "go for it" button.

I tried DeftPDF last night, and the results looked good, but it nearly doubled the size of the file. Upon closer inspection, all it did was duplicate the selected pages, and then crop them to either the left or right half, without actually trimming any image data (the other half was simply hanging off the left or right side of the visible page).

[Giuseppe Donnini]

I would give Scan Tailor a try. It's not perfect, but it might work well enough for what you need.

[Sylvain Cote]

I use ImageMagick command line tools to create, edit, compose, or convert digital images.
Very powerful and scriptable, I modify (rotate, crop, etc) hundreds of files in a matters of seconds or minutes.

[Bill (Smithville NJ)]

(02-17-2021 01:20 PM)Dave Britten Wrote:  I tried DeftPDF last night, and the results looked good, but it nearly doubled the size of the file. Upon closer inspection, all it did was duplicate the selected pages, and then crop them to either the left or right half, without actually trimming any image data (the other half was simply hanging off the left or right side of the visible page).

Dave,

You can always just print the cropped pdf to a new pdf file. The new pdf file will then not have the cropped pieces.

I do this quite often. I receive a pdf that has a lot of white margin. I crop the white margin out and then re-print to a new pdf. I now have a pdf without the white margins and which will display in a larger size.

73
Bill
WD9EQD
Smithville, NJ

[gege]

I also use ScanTailor to do this. Very easy to use and can rotate an flatten pages.

[Dave Britten]

(02-17-2021 02:01 PM)Giuseppe Donnini Wrote:  I would give Scan Tailor a try. It's not perfect, but it might work well enough for what you need.

Oh nice! Looks like it has a "Split Pages" function. I'll give this a try.

(02-17-2021 02:37 PM)Sylvain Cote Wrote:  I use ImageMagick command line tools to create, edit, compose, or convert digital images.
Very powerful and scriptable, I modify (rotate, crop, etc) hundreds of files in a matters of seconds or minutes.

I will definitely keep that in mind. If I ever get to the point where I'm scanning and manipulating hundreds of files, I will definitely want heavy automation, but for now an interactive tool is better so I can figure out what the heck I'm doing.

(02-17-2021 02:47 PM)Bill (Smithville NJ) Wrote:  You can always just print the cropped pdf to a new pdf file. The new pdf file will then not have the cropped pieces.

I do this quite often. I receive a pdf that has a lot of white margin. I crop the white margin out and then re-print to a new pdf. I now have a pdf without the white margins and which will display in a larger size.

That's a good idea that hadn't crossed my mind. Though I scanned the pages as grayscale, and the covers in color. Not sure if the output would end up with all the pages converted to color (i.e. larger file size).

[Eric Rechlin]

I've been scanning a lot of books for my new site lately, and everything has been possible with free tools.

I use ImageMagick to cut two pages into one. I script it so I don't have to manually do it for each file, but here are sample commands for one file:

convert -crop 1656x2540+5+0 hp42s-prog-de-000.png out/hp42s-prog-de-000a.png;
convert -crop 1656x2540+1656+0 hp42s-prog-de-000.png out/hp42s-prog-de-000b.png

That starts at position 5,0 and grabs 1656x2540 for the left page, and starts at position 1656,0 and grabs 1656x2540 for the right page, and saves them in files with "a" and "b" appended to the original filenames.

I then do a mix of automatic and manual cleanup of the pages, optimize them with optipng and some tools I wrote myself, and then run through tesseract-ocr (a modified build I made to fix bugs) to convert each page to PDF, and then the Popper PDF tools to combine the pages into a single PDF.

[robve]

I used Adobe Scan on my cell phone to scan the 360+ pages PC-2500 manual. I did not want to destroy the manual by placing it on a scanner and having to press it flat!

I found that scanning and adjusting the pages works very well on the phone, but is a bit finicky on a small cell phone screen. A tablet makes that a lot easier. The cloud storage that you get is a big plus IMO but requires signing up (for free).

- Rob

[EdS2]

(02-17-2021 02:57 PM)gege Wrote:  I also use ScanTailor to do this. Very easy to use and can rotate an flatten pages.

Oh, free software too! And looks pretty capable:
Dewarping

I've 'scanned' hundreds of pages using my phone, and a sheet of glass, and some books to prop the work up in an open position, so I take one shot of the left page and then one of the right, moving the phone to get a square-on shot. I can do that quite rapidly, but the result could still benefit from some smart processing.

[toml_12953]

(02-17-2021 01:20 PM)Dave Britten Wrote:  I've got a few small books that I'm scanning by pressing them flat on my scanner. The results are pretty good, but of course I get two pages in a side-by-side format doing it this way. Are there any free/cheap tools that could largely automate the process of splitting the pages down the middle and turning them into two individual pages in the PDF? Ideally something that just lets me select a range of pages and click the "go for it" button.

I tried DeftPDF last night, and the results looked good, but it nearly doubled the size of the file. Upon closer inspection, all it did was duplicate the selected pages, and then crop them to either the left or right half, without actually trimming any image data (the other half was simply hanging off the left or right side of the visible page).

You could try https://www.ilovepdf.com/split_pdf

[Dave Frederickson]

The Portable PLUS Service Manual was scanned with a phone app.
http://www.jeffcalc.hp41.eu/hpplus/files...manual.pdf

I think the results look pretty good, but unfortunately I don't know which app was used.

[striegel]

When dealing with small scanning jobs, I use the Microsoft Office Lens app (free) on my iPhone instead of the flatbed scanner. It's made for finding the edges and straightening up images captured at an angle. It lets you output a set of captures directly into PDF.

The larger and more involved scans are better handled with ABBYY PDF Transformer+, which is not free and appears no longer to be available for purchase. So I guess this desktop will have to stick around forever.

Alan