[Libtesseract] Reduce calls to tesseract_raw.init()
Created by: wwqgtxx
When I use the image_to_string() function frequently, I find the tesseract_raw.init()'s call use the most of CPU times (by pstat). Then I read the code about image_to_string() found it call init() to get libtesseract handle each time when call. This is a advise that could use a threadlocal based cache or a class based cache the libtesseract handle to reuse that and I supposed it can make program run faster. Thanks.