https://github.com/tesseract-ocr/tesseract/blob/master/tessdata/configs/pdf
This is different from your installed version. On Fri, 29 Mar 2019, 22:30 Shree Devi Kumar, <shreesh...@gmail.com> wrote: > The default page segmentation mode is different for command line and api. > Specify it explicitly and test. > > On Fri, 29 Mar 2019, 22:12 Lucas L., <infinitepant...@gmail.com> wrote: > >> OK, I am running up against another issue, and it's getting weirder. >> Since Tesseract does not take PDFs as input, this service does the deed of >> breaking a PDF into pages, and then converting each of those pages to an >> image format (either lzw-compressed TIFF or uncompressed PPM if that >> fails). Somehow, if I run ImageMagick and then Tesseract on these pages >> individually from a command line using the same parameters in the service >> code, it runs fine processing the TIFF. But when the service runs, I get: >> Error in fopenWriteStream: stream not opened >> Error in pixWrite: stream not opened >> >> And the output pdf has all of the pages and they are not mangled... >> however they are shrunk into a tiny corner of the page. I have attached the >> resulting file. I feel that it is obvious from the fact that it works when >> I run it outside the service that it is a code issue... however I really am >> not sure what it could be doing differently from my command line. The pages >> come out looking great when I run tesseract on the individual pages >> manually. The errors do not appear when I run the command lines manually. >> >> The command lines and params I am using: >> >> Convert the input PDF (which is scanned and has no OCR layer) to input >> image: >> convert -depth 16 -density 300 -colorspace RGB -despeckle -flatten -compress >> lzw -background white -alpha off "/path/pg_0010.pdf" "/path/pg_0010.tif" >> Process the input image for OCR and output to PDF: >> tesseract -l eng "/path/pg_0010.tif" "/path/pg_0010" pdf >> >> Configuration parameters from /usr/share/tesseract-ocr/4.00/tessdata/ >> configs >> tessedit_create_pdf 1 >> tessedit_pageseg_mode 3 >> tessedit_write_images true >> >> >> On Thursday, March 28, 2019 at 1:31:36 PM UTC-5, Lucas L. wrote: >>> >>> Environment >>> >>> - Tesseract 4.0.0-beta.3-249-g607e >>> - leptonica-1.76.0 >>> - Linux (hostname removed) 4.18.0-16-generic #17 >>> <https://github.com/tesseract-ocr/tesseract/pull/17>-Ubuntu SMP Fri >>> Feb 8 00:06:57 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux >>> >>> Current Behavior: >>> >>> I work at a SaaS firm which provides cloud storage services specializing >>> in documents. As a part of our service, we try to create PDFs with >>> searchable text layers from scanned documents. When processing PPMs which >>> are created by ImageMagick from the original document, Leptonica mangles >>> the image before it can be OCR'd properly by Tesseract. This results in a >>> PDF unreadable by both human eyes and Tesseract. This only seems to happen >>> for some specific documents. >>> How do I know it's Leptonica, specifically? >>> >>> I have executed Tesseract with the config values tessedit_write_images 1 >>> and tessedit_pageseg_mode 0. From my understanding, the second option >>> does not enable OCR at all while processing with Tesseract (which speeds up >>> my test cases) and the first option outputs a .tif debug image which is >>> apparently what Leptonica feeds to Tesseract after processing. That image >>> is also mangled. >>> Sample data >>> >>> I have extracted a single page from a PDF -- the process works on a >>> page-by-page basis and most of the documents we work with contain highly >>> sensitive information, so I had no other option but to do this. Regardless, >>> it is good sample data. The "pg_0009.ppm" file is the original input fed >>> into Tesseract on the command line which was converted from the original >>> scanned document by ImageMagick. The "tessinput.tif" file is the image >>> produced by the tessedit_write_images 1 option which is supposed to be >>> OCR'd by Tesseract. This particular page caused a seg fault in Tesseract, >>> something that doesn't usually happen, and I suspect it is because the text >>> is overlapped so many times that the OCR engine has too much to handle. >>> >>> Google Drive since it's too large for an attachment: >>> https://drive.google.com/file/d/1UCzXYu7iusep-bOD6EcKyBs2qXCqVdu5/view?usp=sharing >>> Expected Behavior: >>> >>> Leptonica leaves the image mostly intact so that Tesseract can provide a >>> proper text layer for the output PDF. Alternatively, a configuration option >>> is available to bypass Leptonica. >>> >>> Any and all help is appreciated with this issue. Thanks for reading. >>> >> -- >> 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 tesseract-ocr+unsubscr...@googlegroups.com. >> To post to this group, send email to tesseract-ocr@googlegroups.com. >> 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/4ac58e80-fd54-49f4-b479-3a33f5ca5388%40googlegroups.com >> <https://groups.google.com/d/msgid/tesseract-ocr/4ac58e80-fd54-49f4-b479-3a33f5ca5388%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 tesseract-ocr+unsubscr...@googlegroups.com. To post to this group, send email to tesseract-ocr@googlegroups.com. 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/CAG2NduV3kWtc73ejBN4vpOLQsEQ%3DESXdtSzcQq0ywn8nTRT5aQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
