First double check if the Pi is not throttling due to overheating or lack of USB power. This may cause the slowdown.
Usually 30/50 px of text height is fine. IF the problem is tesseract, try to use the fast model (or "normal" if using best). I assume you are using the 4.x release. Try tesseract -v to see if you are using all the available CPU optimizations. Try to move the SetSourceResolution outside the loop and see if it changes something (MAYBE it may invalidate some caches or something). The time you are referring to is one single api.GetUTF8Text() call, correct? Lorenzo Il giorno mar 29 gen 2019 alle ore 17:48 Jan Pohanka <[email protected]> ha scritto: > Hello, > > I'm making a simple device used to recognize numbers on pictures taken by > a webcam. All is running on raspberry pi 3. > Everything is like following simple loop (in python for simplicity, but > using C++ api it is the same), images are preprocessed to black and white > > api = PyTessBaseAPI(psm=tesserocr.PSM.SINGLE_WORD) > > for im in images: > api.SetImage(im) > api.SetSourceResolution(70) > ot = api.GetUTF8Text() > > api.End() > > > My problem is that api.GetUTF8Text() call is quite slow and more over it > is getting slower and slower over time. Is there any options how to make > recognition faster? I have tried to resize the image to around 50x10px. The > times starts on around 300ms but then goes up to above 1s which is too slow > for me. I tried both legacy and LSTM algorithms, but they are similar. > > best regards > Jan > > -- > 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 https://groups.google.com/group/tesseract-ocr. > To view this discussion on the web visit > https://groups.google.com/d/msgid/tesseract-ocr/a53b4b25-97e3-47dc-823a-cbb219225eed%40googlegroups.com > <https://groups.google.com/d/msgid/tesseract-ocr/a53b4b25-97e3-47dc-823a-cbb219225eed%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 https://groups.google.com/group/tesseract-ocr. To view this discussion on the web visit https://groups.google.com/d/msgid/tesseract-ocr/CAMgOLLyxu2GY19f6wcB0%3DTVq7O%2Btw-m-KqZ9frjuCuzgFNOTRw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
