Daniel Reetz, the founder of the DIY Book Scanner community, has recently started making videos of prototyping and shop tips. If you are tinkering with a book scanner (or any other project) in your home shop, these tips will come in handy. https://www.youtube.com/channel/UCn0gq8 ... g_8K1nfInQ

Scan Tailor "Enhanced"

Scan Tailor specific announcements, releases, workflows, tips, etc. NO FEATURE REQUESTS IN THIS FORUM, please.
dtic
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Re: Scan Tailor "Enhanced"

Post by dtic » 05 May 2012, 05:28

The new version works well in Win 7. Thank you!

Regarding my point 2 above: I wasn't clear enough. Here's an example. First go to the select content step in ST and do batch process on all images. Next, I want to manually edit selection for some images. I click a thumbnail in the right hand pane. The previous image in the large middle pane now disappears and the "processing" dot animation is display. On my system that takes several seconds. For each image I click. Every time. I got the impression that the time delay is caused by ST reprocessing the select content command on the image each time I click it. So if I click back and forth between page 1 and 2 several times ST will reprocess select content every time. I wondered if it would be possible to add a way to skip the reprocessing through a special action (alt+click).

pejuko
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Re: Scan Tailor "Enhanced"

Post by pejuko » 05 May 2012, 12:19

ScanTailor does not cache the images displayed in the middle pane it should just remember detected (or set) parameters. If you are switching between two images there is still necessary image processing to generate actual view. I don't plan to implement such cache in near future.

dtic
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Re: Scan Tailor "Enhanced"

Post by dtic » 05 May 2012, 14:36

Yes, it does remember the parameters if I do changes to the selection between each switch. So no problem there. It was only the delay I was wishing to get around. My system is somewhat dated though so that might be the weakest link. Out of curiosity can anyone reading this who runs ST on a computer with a fast current gen CPU (Sandy/Ivy Bridge) tell me roughly how long time the select content processing takes for one page?

Tulon
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Re: Scan Tailor "Enhanced"

Post by Tulon » 06 May 2012, 06:15

Depending on the resolution and compression type of your input images, 2 sec for switching between pages might or might not be OK. Try switching between pages on the "Fix Orientation" stage. If it's not significantly faster, that just means most of those 2 seconds are spent on loading a file from disk and decompressing it.
Choosing a good scanning format can help there. Jpeg is going to be the quickest to load, as the files are small, though it's a lossy format, so I wouldn't recommend it, at least not for flatbed scanners. TIFF with LZW compression seems like the best combination among lossless formats.
Scan Tailor experimental doesn't output 96 DPI images. It's just what your software shows when DPI information is missing. Usually what you get is input DPI times the resolution enhancement factor.

dtic
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Re: Scan Tailor "Enhanced"

Post by dtic » 07 May 2012, 11:13

Image load is around 1.5 seconds per image in the Fix Orientation step for 8 megapixel jpeg photos of book pages on my system. So I guess that explains most of the wait in the Select Content step too. I didn't at first think of that since those images display with almost no delay in IrfanView (image viewer application).

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daniel_reetz
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Re: Scan Tailor "Enhanced"

Post by daniel_reetz » 07 May 2012, 11:15

I think irfanview loads the next few images in the directory while you're looking at the current one, which helps with the perception of instantaneous-ness.

Tulon
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Re: Scan Tailor "Enhanced"

Post by Tulon » 07 May 2012, 11:53

Image load is around 1.5 seconds per image in the Fix Orientation step for 8 megapixel jpeg photos.
I would expect Jpeg to load faster than that, though maybe not by much. What input DPI are you specifying for those?
I think irfanview loads the next few images in the directory while you're looking at the current one, which helps with the perception of instantaneous-ness.
It's not something terribly hard to do, in fact I already do it for thumbnails, but:
1. I would only do such a thing in a 64-bit version, as the 32-bit version is address-space constrained.
2. As usual, I don't have enough free time :(
Scan Tailor experimental doesn't output 96 DPI images. It's just what your software shows when DPI information is missing. Usually what you get is input DPI times the resolution enhancement factor.

dtic
Posts: 458
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Re: Scan Tailor "Enhanced"

Post by dtic » 07 May 2012, 16:58

The images where 340 dpi. My computer is likely the bottleneck as it is about 6 years old.

Tulon
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Re: Scan Tailor "Enhanced"

Post by Tulon » 08 May 2012, 02:35

dtic wrote:The images where 340 dpi.
Sounds about right for a 8 megapixels image.
My computer is likely the bottleneck as it is about 6 years old.
Looks like it.
Scan Tailor experimental doesn't output 96 DPI images. It's just what your software shows when DPI information is missing. Usually what you get is input DPI times the resolution enhancement factor.

eL_PuSHeR
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Joined: 28 Jun 2010, 15:25

Re: Scan Tailor "Enhanced"

Post by eL_PuSHeR » 08 May 2012, 02:54

I have also noticed that navigating through the content section seems slower than regular 0.9.11.1 release. I have to do more tests though.

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