Thanks. I figured out how to use ImageMagick to change the mottled gray to green.
michael@argon:~/michael/trunk/src/tides$ convert time.png -fuzz 20% -fill "green" -opaque "gray(60%)" time_green.png [image: time_green.png] michael@argon:~/michael/trunk/src/tides$ tesseract time_green.png - Estimating resolution as 147 10/29/2025 9:43:16 PM On Thursday, October 30, 2025 at 11:57:34 AM UTC-7 [email protected] wrote: > I cannot emphasize this single item (in a long list of stuff one can/must > do before feeding any image to an OCR engine) enough: *tesseract has been > trained to 'read' books, i.e black text on white background. Consequently, > any image preprocessing step(s) that get you there, are strongly advised.* > > This, and lots of other "*I don't wanna hear this 🥴*" important details > show up in the documents and emails listed below: > (I know people like twitter-sized or shorter text, but you've got some > reading to do if you want to be successful at OCRing stuff. We all have to, > it's not simple.) > > *- https://tesseract-ocr.github.io/tessdoc/ImproveQuality.html > <https://tesseract-ocr.github.io/tessdoc/ImproveQuality.html> 🎯* > - > https://github.com/tesseract-ocr/tessdoc/blob/main/tess3/FAQ-Old.md#is-there-a-minimum--maximum-text-size-it-wont-read-screen-text > - > https://groups.google.com/g/tesseract-ocr/c/Wdh_JJwnw94/m/24JHDYQbBQAJ?pli=1 > - https://groups.google.com/g/tesseract-ocr/c/B2-EVXPLovQ/m/lP0zQVApAAAJ > > and then a bunch of messages that are related; I'd rather not repeat > myself, so please take your time and read those threads: some of it may > sound crazy at first, but you're doing something that's touching on the > edge of the original design goals and that means you're bound to meet some > "weird behaviour" along the way. Before I let myself out, *the second > most important piece of advice I can give everyone: use HOCR (which is HTML > content plus coordinates) or TSV output instead of anything else; do not, I > repeat: !DO NOT! output txt format, just because every internet wizard out > there does it in their blog: txt (text) format is minimal-information and > you are way better off with a maximal-information output for when you need > to diagnose trouble* -- plus, now you've seen the workflow diagram that's > part of the info above, *turning HOCR/TSV into TXT should be part of your > postprocessing*, AFAIAC. > Other direct or sideways relevant blurbs to be read here (again, consider > reading the entire threads; OCR is one of those activities where 'quickly > scanning my text books to pass my exam' as you previously learned at school > is not going to get you closer to success faster, on the contrary: > > - https://groups.google.com/g/tesseract-ocr/c/jWdpUF7mTxE > - https://groups.google.com/g/tesseract-ocr/c/vrBc1FPeprQ/m/GxTlapF-BwAJ > - https://groups.google.com/g/tesseract-ocr/c/c_S7GG5njkw/m/OPQ6q5zBAQAJ > - https://groups.google.com/g/tesseract-ocr/c/8BerjYWGGQU/m/KwSz7724AQAJ > - https://groups.google.com/g/tesseract-ocr/c/YLOkyuOMsrs/m/wEKTYtfQAAAJ > > HTH > > Met vriendelijke groeten / Best regards, > > Ger Hobbelt > > -------------------------------------------------- > web: http://www.hobbelt.com/ > http://www.hebbut.net/ > mail: [email protected] > mobile: +31-6-11 120 978 > -------------------------------------------------- > > > On Thu, Oct 30, 2025 at 6:26 PM Michael Schuh <[email protected]> wrote: > >> I am trying to extract the date and time from >> >> [image: time.png] >> >> I have successfully use tesseract to extract text from other images. >> tesseract does not find any text in the above image, >> >> michael@argon:~/michael/trunk/src/tides$ tesseract time.png out >> Estimating resolution as 142 >> >> michael@argon:~/michael/trunk/src/tides$ cat out.txt >> >> michael@argon:~/michael/trunk/src/tides$ ls -l out.txt >> -rw-r----- 1 michael michael 0 Oct 30 08:58 out.txt >> >> Any help you can give me would be appreciated. I attached the time.png >> file I used above. >> >> Thanks, >> Michael >> >> -- >> > 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 view this discussion visit >> https://groups.google.com/d/msgid/tesseract-ocr/77ac0d2b-7796-4f17-8bc6-0e70a9653adan%40googlegroups.com >> >> <https://groups.google.com/d/msgid/tesseract-ocr/77ac0d2b-7796-4f17-8bc6-0e70a9653adan%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- 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 view this discussion visit https://groups.google.com/d/msgid/tesseract-ocr/06d9bba6-53e0-4547-93b8-b4b9345a687dn%40googlegroups.com.
