Runeberg

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302 discussions

Re: Runeberg Digest, Vol 22, Issue 2
by Mats Eklof 09 Feb '07

09 Feb '07

dear Sven de Marothy, You are doing great work with your camera I can understand from your report *Digitizing with a camera - some results.* ** I can confirm *all your findings* in your report regarding using digital camera for OCR. Some years ago I used a Canon S40 4Megapixel camera and did som OCR of single book pages with an old version of FineReader. I photographed maybe 50 or 100 big books, mostly handheld (camera and book) with day light from window. But very few of them I OCRed. My experience was that the OCR result was as good as with a scanner, but if I wanted to do OCR also I had to spend more time photographing each book then if I just stored the books as pictures, so therefore I saved time by just going quickly through most of the books. Now I have a Canon A620 7Megapixel and the results are just a little better. I also travel with a super small tripod and a big screw for attachement to tables (I put the book on the floor between the window and table). I do a 60-page book in 5-10 minutes with a double page on each photo and about double time with a single page on each photo. The time also depends on how soft the book binding is and how good my working position is under the window. I think the biggest problems with FineReader is that it does not accept scans that are not flat, and that it is sensitive to shadows. There is also a need for an expanded internal dictionary in Finereader. *An expanded dictionary that Finereader uses in the recognition phase (not later at spelling check). *Do you know if Finereader has this possibility? I also need a Finereader that has built in recognition of diacritacal marks like you know åöä in Swedish. I do Indian language books. mvh Mats Eklöf Huskvarna 2007/2/9, runeberg-request(a)lists.lysator.liu.se < runeberg-request(a)lists.lysator.liu.se>: > > Send Runeberg mailing list submissions to > runeberg(a)lists.lysator.liu.se > > To subscribe or unsubscribe via the World Wide Web, visit > http://lists.lysator.liu.se/mailman/listinfo/runeberg > or, via email, send a message with subject or body 'help' to > runeberg-request(a)lists.lysator.liu.se > > You can reach the person managing the list at > runeberg-owner(a)lists.lysator.liu.se > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Runeberg digest..." > > > Today's Topics: > > 1. Re: Halland (Sven de Marothy) > 2. Digitizing with a camera - some results (Sven de Marothy) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 8 Feb 2007 21:04:21 +0100 > From: "Sven de Marothy" <svendem(a)gmail.com> > Subject: Re: [Runeberg] Halland > To: runeberg(a)lists.lysator.liu.se > Message-ID: > <94420310702081204u3c0bdf88x8ad213fe3a51442d(a)mail.gmail.com> > Content-Type: text/plain; charset="iso-8859-1" > > On 2/8/07, Lars Aronsson <lars(a)aronsson.se> wrote: > > > Vilka författare är från Halland? > > > Carl Bildt? I och för sig gäller det bara Carl Bildt (1949-) och inte > Carl Bildt (1850-1931), som hade kunnat vara aktuell. > > Annars är Olof Dalin självskriven tycker jag. Läge att digitalisera > Then Swänska Argus? > > Och hej förresten, jag är ny på listan. :) > > /Sven >

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Digitizing with a camera - some results
by Sven de Marothy 08 Feb '07

08 Feb '07

HI all, I thought I'd share some thoughts on the issue of using digital cameras, since I'm a long time scanner-user (my first being a hand-scanner - remember them?) and a relatively new digital camera owner. Since trying out book scanning (save some money on photocopies at the library) was one of my main reasons for buying one, runeberg.org/admin/camera.html was an interesting thing to read before I did so. But the document is a little bit old, so here are my experiences with my Samsung NV10 10 megapixel camera: One of my first experiences is that a ten megapixel camera can indeed get quite good resolution (in DPI), comparable to that of a low-end scanner. The NV10 is a compact camera, but at the shortest focus distance (about 6 cm) I get a resolution of about 2000 DPI, although that numbers should be taken with a grain of salt, due to ISO and other interpolation techniques. But even half that is still a pretty good number. For an A4 (or US letter) page, we're talking about 300-400 DPI. Now, my experience (using finereader) is that 10 megapixels is more than you need for good OCR. I also get the impression that the issue of lighting is a bit overemphasized; I've had good results even with ambient lighting, as long as the page/camera/photographer is positioned to avoid shadows. To rank the pitfalls: The definite number one issue is page geometry. The page needs to be as flat as possible. While FineReader didn't seem to have much problems with low contrast, it definitely had problems with any page that wasn't flat. So the best way to photo books seems to be to position them open at a little over 90 degrees, with the page being photographed as flat as possible. (you can speed this up by photographing the odd and even pages in two passes) The second issue is sharpness, which seems quite vital as well. The camera and book need to be steady, and the camera needs to be correctly focused. With some practice, even hand-held results work fine, it's just more difficult. On the positive side, the sharpness can be checked immediately after taking the picture. If the picture is bad, it can still be salvaged in most cases with some post-processing in Photoshop or similar. Third, I would put the aforementioned issue with lighting. And fourth, I'd bring up lens abberation, the slight 'fishbowl' effect you get with the camera. It usually isn't a big enough distortion to have an effect on OCR though, but it becomes very noticable in images, due to the straight lines (of the image border, if nothing else). Images suffer a lot from uneven lighting and lack of color-correctness. So to summarize: I've found using a digital camera to be a very fast, portable and convenient way to digitize text, and that even working with ambient lighting and the camera hand-held ("field conditions") it's quite possible, with some practice, to get results that OCR nearly as well as from a scanner. The big drawback is images; it's not possible, however, to get a decent image under "field conditions", at least not without spending quite a bit of time doing post-processing, which means cancelling out one of the main benefits of using a camera in the first place. So for an illustrated book, I wouldn't recommend using a camera; at least not as a time-saving device. But for plain text the camera can be a better option. (depending on whether you have a sheet-fed scanner, and whether you want to preserve the book or not, etc) When it comes to older Swedish texts in particular, the vast majority of OCR errors would seem to be due to archaic spelling not included in the software's dictionary, and that's the same with either a camera or a scanner. (Speaking of which, perhaps Runeberg.org could cook up some OCR dictionaries for different time periods?) /Sven

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Halland
by Lars Aronsson 08 Feb '07

08 Feb '07

Projekt Runeberg, Den här månadens startsida uppmärksammar texter om landskapet Halland, både nytillkomna och sådana vi redan hade, http://runeberg.org/ Men vilka är dina bästa Hallands-texter i Projekt Runeberg? Vilka länkar borde jag lägga till i listan på förstasidan? Vilka författare är från Halland? Vi hoppas givetvis att fler vill hjälpa till att korrekturläsa de inscannade texterna om Halland. Det är lätt att komma igång. Tipsa gärna bekanta med anknytning till Halland. == SUMMARY IN ENGLISH == I'm inviting suggestions for this month's front page, focusing on the Swedish province Halland, http://runeberg.org/ -- Lars Aronsson (lars(a)aronsson.se) Projekt Runeberg - deine digitale Bibliothek - http://runeberg.org/

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Svenska Fornsånger
by Erik Sjölund 17 Jan '07

17 Jan '07

Hej, Verket "Svenska Fornsånger" består totalt av tre delar. Jag har scannat in del ett som publicerades 1834. Jag tror de två andra delarna blev publicerade några år senare. Så här gick jag till väga: Jag använde en scanner av modellen "Epson Perfection 1660 Photo". Med mjukvaran XSane ( på Linux ) så scannade jag in i 600 dpi gråskala och sparade i PNM-format. I XSane ställde jag då in följande: Gamma value: 1.42 Brightness: 12.3 Contrast: 12.3 Så här i efterhand så undrar jag om det är bra att ändra dessa värden. Kanske är det bättre att låta bli och istället låta allt sådant göras med bildbehandling i efterhand? Varje inscannad bild blev 24 MB och den består av 2 boksidor. Sedan roterade jag bilderna med programmet "ImageMagick" version 6.2.8. och sparade ner dom i bildformatet TIFF-G4. Jag provade då att använda några olika procent-värden till flaggan "-threshold". Procent-värdet anger hur ljus en grå punkt måste vara för att bli betraktad som vit när bilden görs om till svart-vitt. ( se det bifogade bash-skriptet "convert_to_monochrome.sh" ) Därefter provade jag att rita ut rektanglar på bilderna för att kunna se var sidorna skulle beskäras. convert -draw "fill transparent stroke black stroke-width 2 rectangle 200,20,2550,4000" och så vidare.... De koordinater jag hittade använde jag sedan till flaggan "-crop", t ex så här, convert -crop 2350X4030+200+10 uppslag.tiff vänster-sida.tiff convert -crop 2350X4030+2750+10 uppslag.tiff höger-sida.tiff Nu släpper jag materialet fritt ( http://creativecommons.org/licenses/publicdomain/ ) och det går att ladda ned här: http://www.abc.se/~m10828/svenska_fornsanger/Articles.lst ( 3 kB ) http://www.abc.se/~m10828/svenska_fornsanger/bw_54.zip ( 21 MB ) http://www.abc.se/~m10828/svenska_fornsanger/bw_57.zip ( 23 MB ) http://www.abc.se/~m10828/svenska_fornsanger/bw_60.zip ( 25 MB ) http://www.abc.se/~m10828/svenska_fornsanger/bw_63.zip ( 27 MB ) ( 54, 57 ,60 och 63 anger olika threshold-värden ) Jag har inte tillgång till något OCR-program så jag hoppas någon annan kan ta över här och lägga upp materialet på www.runeberg.org. hälsningar, Erik Sjölund

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Bellmans samlade skrifter
by Erik Sjölund 31 Dec '06

31 Dec '06

Hej, Jag såg att någon önskat sig "Bellmans samlade skrifter" på http://runeberg.org/wiki/%D6nskelista Jag köpte för ett tag sedan "Bellmans samlade skrifter" från 1861. Även om jag inte hunnit undersöka saken så verkar det högst troligt att verket inte längre är skyddat av upphovsrätt. Jag kan tänka mig att klippa upp böckerna om det på det sättet går att automatisera inscanningen till Projekt Runeberg. ( alltså ett sådant förfarande: http://runeberg.org/admin/snuff.html ) Men för detta behöver jag hitta en automatscanner. Kanske hittar jag en på egen hand men om du som läser det här har något tips på hur jag ( eller någon annan ) automatiskt kan scanna in böckerna så tar jag tacksamt emot det. ( Jag bor i Stockholm ). hälsningar, Erik Sjölund

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Projekt Runeberg
by Lars Aronsson 22 Dec '06

22 Dec '06

Projekt Runeberg, (summary in English below) De senaste veckorna har vår webbplats varit otillgänglig flera gånger. Vi beklagar detta och ska försöka ta tag i problemen på allvar efter jul och nyår. Vi har nu flera nya verk inscannade och avfotograferade. Vår startsida är uppdaterad för att visa detta, http://runeberg.org/ Jag vill härmed önska er alla en God Jul och ett Gott Nytt År! --- Our website has been unavailable several times in the recent weeks. We're sorry for this and hope to address these problems after the holidays. Some new works have been scanned or photographed and our front page is updated, http://runeberg.org I wish you all a Merry Christmas and a Happy New Year! -- Lars Aronsson (lars(a)aronsson.se) Projekt Runeberg - fri nordisk litteratur - http://runeberg.org/ Project Runeberg - free Nordic literature - http://runeberg.org/

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Problem med Runeberg-sajten??
by Ingemar Olson 18 Dec '06

18 Dec '06

Hej på Redaktionen. På sistone tycker jag att runeberg.org inte fungerar lika bra som det brukade. Allting försvinner i mitten på eftermiddagen (där jag bor, men omkring midnatt i Sverige) och jag vet inte när den kommer tillbaka. Följande dagen - samma sak - jag har kanske tid att korrekturläsa EN sida, och sen försvinner det igen! Jag gissar att ni har problem som ni försöker lösa på natten, men ni har inte underrättat någon - på Runeberg-List åt minstone, som jag antar att de flesta korrekturläsare är med på. Är det möjligt att tala om för oss alla vad för sorts problem ni har, och när ni tror att allt skall bli "som vanligt" igen? Ingemar _________________________________________________________________ Off to school, going on a trip, or moving? Windows Live (MSN) Messenger lets you stay in touch with friends and family wherever you go. Click here to find out how to sign up! http://www.telusmobility.com/msnxbox/

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Upload of a new volume
by Simen Bjelke 31 Oct '06

31 Oct '06

Hi, I have finaly gotten around to scan the rest of Volume 1 of "Urda, et norsk antikvarisk Tidskrift". And now I want to upload it. But on the upload page there are several things that I need help with, the "verkskod" and the "författarkod". How do I know what code to use? Thanks for all your help so far! Simen Bjelke

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Hi - and deskew
by Simen Bjelke 05 Sep '06

05 Sep '06

Hi, I am new to the list, quite new to Runeberg at all actually. I first discovered the site two years ago when my interest in old Norse history grew, and i had bought my own copy of Salmonsens Konversasjonsleksikon (for a mere 1000NOK!), and to find that someone actually was taking the time to scan this masterpiece was quite amazing. Now Runeberg keeps growing and more and more literature is added. Now I have come across some material that I feel should be shared with others, and runeberg is a perfect place to make literature available to everyone. I have a normal A3 scanner so I might not be able to scan the pages perfectly straight, and that brings me to deskew. What deskew tool should one use, and I hope there are some free alternatives out there. Or maybe there is an option like this in photoshop or other wide-market application? If everything goes as planned I hope to be able to upload something in a couple of weeks, getting hold of these books was quite a struggle... I am also so fortunate that they have a license of ABBYY FineReader at my fathers workplace, so I should be able to supply OCR of the pages as well. Anyhow, I appreciate all your hard work. Greetings Simen Bjelke

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Projekt Runeberg not quite dead yet
by Lars Aronsson 07 Aug '06

07 Aug '06

Projekt Runeberg, Vår server tog semester i lördags morse och har idag återgått i tjänst. Hoppas helgen var trevlig. Our server went on holiday Saturday morning, but has now returned to work. Hope you had a nice weekend. -- Lars Aronsson (lars(a)aronsson.se) Project Runeberg - free Nordic literature - http://runeberg.org/

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