Acceptance Criteria:
- The new Wikimedia OCR should accept Tesseract options through the API like: multiple languages, PSM, Engine.
Description
Description
Related Objects
Related Objects
- Mentioned In
- T282141: Wikimedia OCR: Validate Tesseract options
T282060: Support PSM page segmentation option in the UI
T281964: Wikimedia OCR: Validation errors throw 500 exception
T281539: Wikisource OCR: can we provide a link to the form page within proofread page? - Mentioned Here
- T280214: Wikisource OCR: Accept Google options on the API
Event Timeline
Comment Actions
The multiple languages part of this will be dealt with in T280214 (because the lang list is common to both engines). We might want to still do some per-engine verification of the language codes though.
Comment Actions
PR merged: https://github.com/wikimedia/wikimedia-ocr/pull/22
Note that depending on what options you choose, you might get errors about an invalid DPI (dots per inch). In production/staging this will display as a 500 error page. We're not really sure what conditions require you to set the DPI, and in my testing even when I did I would still sometimes get the same error, so we're omitting a DPI option for the time being. See discussion at https://github.com/wikimedia/wikimedia-ocr/pull/22#discussion_r625531031
Comment Actions
I've tested some combinations of the Tesseract options via the UI. I see variations in the returned OCR text, so I guess that means the options are being passed to Tesseract.
For example, compare:
- https://ocr-test.wmcloud.org/?image=https%3A%2F%2Ffanyv88.com%3A443%2Fhttps%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F1%2F1e%2FThe_Book_of_Scottish_Song.djvu%2Fpage20-1024px-The_Book_of_Scottish_Song.djvu.jpg&engine=tesseract&psm=3&oem=3
- https://ocr-test.wmcloud.org/?image=https%3A%2F%2Ffanyv88.com%3A443%2Fhttps%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F1%2F1e%2FThe_Book_of_Scottish_Song.djvu%2Fpage20-1024px-The_Book_of_Scottish_Song.djvu.jpg&engine=tesseract&psm=12&oem=3
Test environment: https://ocr-test.wmcloud.org Version 0.2.0
Comment Actions
Testing on the above and switching the tesseract PSM options yileded 500 errors
https://ocr-test.wmcloud.org/?image=https%3A%2F%2Ffanyv88.com%3A443%2Fhttps%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F1%2F1e%2FThe_Book_of_Scottish_Song.djvu%2Fpage20-1024px-The_Book_of_Scottish_Song.djvu.jpg&engine=tesseract&psm=3&oem=3
https://ocr-test.wmcloud.org/?image=https%3A%2F%2Ffanyv88.com%3A443%2Fhttps%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F1%2F1e%2FThe_Book_of_Scottish_Song.djvu%2Fpage20-1024px-The_Book_of_Scottish_Song.djvu.jpg&engine=tesseract&psm=12&oem=3