tps://github.com/tesseract-ocr/tesseract/wiki/ImproveQuality#rescaling Here is written the following.
Rescaling Tesseract works best on images which have a DPI of at least 300 dpi, so it may be beneficial to resize images. For more information see the FAQ <https://github.com/tesseract-ocr/tesseract/wiki/FAQ#is-there-a-minimum-text-size-it-wont-read-screen-text> . The problem is that image does not have DPI unless it has no size. The size here does not mean resolution, for example 600x400 pixels. The size means how many inches it has vertically and horizontally, and that how we calculate the DPI (dot per inch). It means if I zoom in or zoom out exactly the same image its DPI will decrease and increase correspondingly. So here is the question, how tesseract opens the image, how tesseract measure the size of iameg and what kind of size that image has at the time when tesseract starts reading and calculate the DPI. It is meaningless to say that image has fixed DPI, it has DPI depending to its size. -- *********************************************************** This message may contain confidential and/or privileged information. If you are not the addressee or authorized to receive this for the addressee, you must not use, copy, disclose or take any action based on this message or any information herein. If you have received this message in error, please advise the sender immediately by reply e-mail and delete this message. Thank you for your cooperation. *********************************************************** -- 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/d66494db-f1a4-4ae2-9fb2-2afddaab1385%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
