问题
I am trying to install tesseract on my mac using homeBrew. When I try installing, everything seems to be good but I get the following error/message:
Warning: Could not link leptonica. Unlinking...
Error: The `brew link` step did not complete successfully
The formula built, but is not symlinked into /usr/local
You can try again using `brew link leptonica'
When I try running a tesseract function, I get the following error:
Tesseract Open Source OCR Engine v3.02.02 with Leptonica
Error in pixReadStreamPng: function not present
Error in pixReadStream: png: no pix returned
Error in pixRead: pix not read
Unsupported image type.
I have image magick installed and the command I used to install tesseract was:
brew install tesseract
Can anyone please tell me what I can do to get tesseract working? Thank you!
EDIT When I run brew link leptonica, I get the following error:
Could not symlink file: /usr/local/Cellar/leptonica/1.69/bin/yuvtest
Target /usr/local/bin/yuvtest already exists. You may need to delete it.
回答1:
After installing / removing and re-installing tesseract i found the solution for the same problem you have. On your terminal logs, while installing tesseract, you will see:
Error: The brew link step did not complete successfully
The formula built, but is not symlinked into /usr/local
Could not symlink bin/convertfilestopdf
Target /usr/local/bin/convertfilestopdf
already exists.
You may want to remove it:
rm '/usr/local/bin/convertfilestopdf'
To force the link and overwrite all conflicting files:
brew link --overwrite leptonica
To list all files that would be deleted: brew link --overwrite --dry-run leptonica
What i did was running: brew link --overwrite leptonica
"Linking /usr/local/Cellar/leptonica/1.71_1... 45 symlinks created"
Everything should work perfectly.
Hope this can be a help for you
回答2:
It sounds a bit silly, but have you tried deleting yuvtest? I just tried it myself - the file is automatically generated by brew link leptonica. As for why it isn't working, is it possible you had some version of leptonica/tesseract installed previously? Another reasonable guess at a fix would be
brew uninstall tesseract; brew install tesseract
So far as I know, image magick being installed shouldn't matter for tesseract. They don't have anything in common.
回答3:
Now, as of September 2019, there are no longer any optional install flags available
brew options tesseract
yield nothing. But,
brew info tesseract
yields the following key info:
This formula contains only the "eng", "osd", and "snum" language data files.
If you need all the other supported languages, `brew install tesseract-lang`.
Therefore, to get all of the languages installed, you need to now install a separate library called tesseract-lang.
Updated installation:
brew install tesseract
brew install tesseract-lang
Hope this helps.
old in case this is useful:
Now, as of January 2019, Tesseract installs fine via homebrew, as long as you have xquartz installed first, brew cask install xquartz. Then you can do the following: brew install tesseract --with-all-languages --with-serial-num-pack --with-training-tools
回答4:
Tesseract is now dependent on Leptonica being installed.
The error messages you are seeing relate to these files:
Leptonica is configured to handle image I/O using these external libraries: libjpeg, libtiff, libpng, libz, libgif, libwebp.
These libraries are easy to obtain. For example, using the debian package manager: sudo apt-get install where = {libpng12-dev, libjpeg62-dev, libtiff4-dev}.
Source: Leptonica unofficial documentation
I found that homebrew would install some but not all of the libraries.
来源：https://stackoverflow.com/questions/17140753/tesseract-install-mac-os