You can use this tool to get a traineddata file of whichever font you want. After that move the traineddata file in your tessdata folder. To use tesseract with the new font in Python put lang = “Font”as the second parameter in the image_to_string function. It improves accuracy significantly but still makes mistakes of course. … Read more
On mac OS type brew install tesseract-lang Installs all languages, you can check them by, tesseract –list-langs
Initially OCRopus was actually using Tesseract as recognition engine inside, but later they changed it to their own brand-new engine. It is still fresh and not mature. We have been making accuracy comparison about year ago, and OCRopus was definitely losing to Tesseract, I am not even talking about commercial enignes. Since then I stopped … Read more
Most commercial OCR engines will return word and character coordinate positions but you have to work with their SDK’s to extract the information. Even Tesseract OCR will return position information but it has been not easy to get to. Version 3.01 will make easier but a DLL interface is still being worked on. Unfortunately, most … Read more
To detect the rotation angle, use the Hough transformation. For noise reduction, replace any pixel, that does not have a neighbour (north, east, south or west) with the same color (a similar color, using a tolerance threshold), with the average of the neighbours. Search for vertical white gaps for layout detection. Slice along the vertical … Read more
Success. Many thanks to the people at the Pattern Recognition and Image Analysis Research Lab (PRImA) for producing tools to handle this. You can obtain them freely on their website or github. Below I give the full solution for a Mac running 10.10 and using the homebrew package manager. I use wine to run windows … Read more
SESHAT is a open source system written in C++ for recognizing handwritten mathematical expressions. SESHAT was developed as part of a PhD thesis at the PRHLT research center at Universitat Politècnica de València. An online demo:http://cat.prhlt.upv.es/mer/ The source: https://github.com/falvaro/seshat Seshat is an open-source system for recognizing handwritten mathematical expressions. Given a sample represented as a … Read more
Recognizing only numbers is actually answered on the tesseract FAQ page. See that page for more info, but if you have the version 3 package, the config files are already set up. You just specify on the commandline: tesseract image.tif outputbase nobatch digits As for the threshold value, I’m not sure which you mean. If … Read more
Disable DEP for specific applications. How to Disable DEP for Specific Applications Click the Start button on your Windows computer and choose Computer > System Properties > Advanced System Settings. From the System Properties dialog, select Settings. Select the Data Execution Prevention tab. Select Turn on DEP for all programs and services except those I … Read more
Create a config file (e.g “letters”) in tessdata/configs directory – usually /usr/share/tesseract/tessdata/configs or /usr/share/tesseract-ocr/tessdata/configs And add this line to the config file: tessedit_char_whitelist abcdefghijklmnopqrstuvwxyz …or maybe [a-z] works. I don’t know. Then call tesseract similar to this: tesseract input.tif output nobatch letters That will limit tesseract to recognize only the wanted characters.