问题
Can anyone suggest me how to convert a scanned image into a searchable image or a scanned pdf to a searchable pdf ?
I have been stuck in this situation since quite a while now.
i have tried pdfocr application in ubuntu but no success.
回答1:
Tesseract version 3.03 supports creation of searchable PDF from image. For PDF, you can use GhostScript to convert it to image before sending it to Tesseract.
https://github.com/tesseract-ocr/tesseract
回答2:
Currently, there is no right way of doing this on Ubuntu. All OCR engines output plain text and there is no way to add that text as a hidden layer on PDF over the image text.
Option 1: Use gscan2pdf which will make you a searchable PDF, but the OCRed text is placed in the top-left corner of the page, is invisible and much too small.
Option 2: Use PDF X-Change Viewer which has an option to OCR and works correctly by adding a text layer over the scanned image which is in concordance with it. You'll have to run it in wine, because it is a Windows application.
来源：https://stackoverflow.com/questions/24848808/scanned-image-pdf-to-searchable-image-pdf