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charlesw / tesseract

A .Net wrapper for tesseract-ocr
Apache License 2.0
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Empty result when screen scaling is not at 100% #567

Open dfyx opened 3 years ago

dfyx commented 3 years ago

Edited because of new info that makes it way less mysterious: When screen scaling is set to something other than 100% in Windows 10, Tesseract produces " \n" (a space and a newline) no matter the input. I'm feeding in System.Drawing.Bitmap objects through the Page TesseractEngine.Process(Bitmap image, Rect region, PageSegMode? pageSegMode = null) extension method. Those bitmaps don't come from screen captures but either from files or video sources, so I can't see why they would be affected by the screen scaling. My guess is that something inside Tesseract goes wrong.

Original description:

I'm seeing a really weird behavior. I've written and compiled a program on my main machine (Windows 10 Pro 64 bit, AMD Ryzen 5 3600X, GTX 3070, 32 GB RAM) and get good results there. When I run the same binary with the same inputs on my laptop (Huawei Matebook X Pro 2020 with Windows 10 Pro 64 bit, Core i7-10510U, GeForce MX 250 / Intel UHD Graphics, 16 GB RAM), I get empty results (a space and a newline to specific). There are no exceptions or log output, just the nonsense result.

dfyx commented 3 years ago

Closed because it turned out to be an unrelated issue. The input for the region parameters corrected for screen scaling which led to Tesseract looking at the wrong part of the image