Hi, I suspect you did a cut and paste or some edits and now you have some non-printable characters in your command line (the question mark boxes). Write it again from scratch.
And you are missing one parameter in the command line, the output file, you can use "-" for standard output. $ tesseract --psm 6 image.png - You are also using version 3.x, you should probably upgrade to 4.x. Lorenzo Il giorno mar 23 apr 2019 alle ore 16:59 alex kelly <[email protected]> ha scritto: > Thanks for getting back to me. When i run it i get an error, any ideas > why and how to resolve it? > > pi@ShopFloorOCRReader:~ $ tesseract --psm 6 > "test_images/cropped_image.jpg" > Tesseract Open Source OCR Engine v3.04.01 with Leptonica > read_params_file: parameter not found: ���� > > > > On Sunday, 14 April 2019 10:59:53 UTC+1, Lorenzo Blz wrote: >> >> Hi Alex, >> you need to pre process the image a little. >> >> First negate it, tesseract expect dark on white background text. >> >> Then use --psm 6 to tell tesseract that this is a single block or text >> and not a complex page to split in paragraphs. Also try psm 7, single line. >> >> tesseract --psm 6 cropped_image.jpg - >> 1.4 95500>0 >> >> Now by stretching the contrast (or and OTSU/adaptive threshold) and >> straightening the image I get (almost) correct results, see the attached >> image. >> >> 1 4 9 55 0 5 >> >> Ideally you want an image as simple as possible, black text on white >> background. You may also try to crop the black border out, if possible. >> >> Have a look here on how to isolate blocks of text: >> >> >> https://www.pyimagesearch.com/2017/07/17/credit-card-ocr-with-opencv-and-python/ >> >> https://www.pyimagesearch.com/2017/02/20/text-skew-correction-opencv-python/ >> >> >> Bye >> >> Lorenzo >> >> >> >> Il giorno sab 13 apr 2019 alle ore 19:36 alex kelly <[email protected]> >> ha scritto: >> >>> Hello, >>> >>> I'm trying to OCR a small grey scale image, its for a energy meter but >>> it says the image is to small - the full response is below: >>> >>> pi@OCRReader:~ $ tesseract test_images/cropped_image.png out >>> Tesseract Open Source OCR Engine v3.04.01 with Leptonica >>> Error in pixGenerateHalftoneMask: pix too small: w = 230, h = 50 >>> Empty page!! >>> Error in pixGenerateHalftoneMask: pix too small: w = 230, h = 50 >>> Empty page!! >>> >>> How can I make tesseract-ocr read the value? >>> >>> I can send this to google computer vission API but i would rather do >>> this on the device (rather than sending it to the cloud) and I was >>> recommended tesseract. If there is a better solution, please let me >>> know. >>> >>> Thanks >>> >>> -- >>> 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/2314d522-ac6d-4abc-8d17-42a198503b7d%40googlegroups.com >>> <https://groups.google.com/d/msgid/tesseract-ocr/2314d522-ac6d-4abc-8d17-42a198503b7d%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/455d9579-a476-4d85-b6d3-ca1c34853c2b%40googlegroups.com > <https://groups.google.com/d/msgid/tesseract-ocr/455d9579-a476-4d85-b6d3-ca1c34853c2b%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/CAMgOLLwAWtWALGA6mndyNjfVRP9L1H34q2Ta8q0SYshEcmLyPQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
