I have tried with the English traineddata and got similar results. However, I had not tried recognizing the entire 'prepared-image' with psm 6 and I see that gives pretty good results. The thing is, I need to know the location of each character. That is which row and column it is placed on. If Tesseract fails recognizing a single letter when recognizing the entire image, I have no way of knowing which letter is missing and therefore I do not know the location of any of the letters.
Den fredag den 14. november 2014 18.24.15 UTC+1 skrev shree: > > Have you tried with the existing english traineddata? > > I get good recognition with your 'prepared-image'? > > If that is the kind of image you need to OCR, you could do that with psm 6 > and then split each letter separately? > > ShreeDevi > ____________________________________________________________ > भजन - कीर्तन - आरती @ http://bhajans.ramparivar.com > > On Fri, Nov 14, 2014 at 7:12 PM, Simon Støvring <[email protected] > <javascript:>> wrote: > >> Hello, >> >> I am trying to recognize single characters written with the Gotham Bold >> font. I have trained Tesseract by following Michael Jay Lissners guide >> "Adding New Fonts to Tesseract 3 OCR Engine" >> <http://michaeljaylissner.com/posts/2012/02/11/adding-new-fonts-to-tesseract-3-ocr-engine/>. >> >> I trained it using a newspaper article and removed all characters that I am >> not interested in as well as making sure all characters are upper case as I >> am not going to match lower case characters. >> >> I run Tesseract with my custom language and with page segmentation set to >> 10, which treat the image as a single character. >> >> While most of the matches are fine, I am getting a lot of incorrect >> matches. For example, the below image of the letter "B" is matched as an >> "X". I cannot figure out why this is. >> >> >> <https://lh4.googleusercontent.com/-AOLPnD7nXJY/VGYC58I-roI/AAAAAAAAASQ/kTJq9eSNMy4/s1600/0-4.png> >> >> And the "B" below which looks the same as the above but it is in fact not >> the same image, is not matched to anything. Tesseract does not know what is >> on the image. >> >> >> <https://lh4.googleusercontent.com/-b0kMaAzcN-Y/VGYFI6NOzjI/AAAAAAAAASk/c9EfpR8CjWI/s1600/1-7.png.png> >> >> >> The below "C" is not matched to anything. Tesseract cannot figure out >> what is on the image. >> >> >> <https://lh5.googleusercontent.com/-ZKl8jE2Orto/VGYEs2xzGlI/AAAAAAAAASc/2xTXomhIkWI/s1600/0-8.png> >> The same goes for the "U" below. >> >> >> <https://lh5.googleusercontent.com/-fciIyBe9bDw/VGYFRh3YBNI/AAAAAAAAASs/29WZQUHqPmE/s1600/1-8.png> >> And it thinks the "E" below is a "K". >> >> >> <https://lh4.googleusercontent.com/-ZZFkr77drgM/VGYFcDydDXI/AAAAAAAAAS0/RQ1UO8U3rOY/s1600/1-9.png> >> >> The above errors are just examples. There are others but I think those >> four examples illustrate the quirks I'm currently dealing with. >> >> I manually slice the image below into images of single characters like >> the ones above. Maybe a completely different approach is better? >> >> >> <https://lh4.googleusercontent.com/-TfwZnXosqB0/VGYFjLppJ9I/AAAAAAAAAS8/Oun76IHLwks/s1600/prepared_image.png> >> Does anyone know how I can improve the recognition of single characters? >> I'ld like the above examples to match correctly but generally it's just not >> good enough and I'ld like to know if there's any way I can improve it. >> Should I train differently? Should I pass other configurations or should I >> process the images before trying to recognize the characters? >> >> Best regards, >> Simon B. Støvring >> >> -- >> You received this message because you are subscribed to the Google Groups >> "tesseract-ocr" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at http://groups.google.com/group/tesseract-ocr. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/tesseract-ocr/e905020c-f0b2-47b6-b09c-e01efa96dcc1%40googlegroups.com >> >> <https://groups.google.com/d/msgid/tesseract-ocr/e905020c-f0b2-47b6-b09c-e01efa96dcc1%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> For more options, visit https://groups.google.com/d/optout. >> > > -- You received this message because you are subscribed to the Google Groups "tesseract-ocr" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/tesseract-ocr. To view this discussion on the web visit https://groups.google.com/d/msgid/tesseract-ocr/44df342b-9d7f-42bf-9d1f-d2a9028426ac%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
