The two can be complementary. If you read the paper on OpenCV:
https://github.com/tesseract-ocr/docs/blob/master/tesseracticdar2007.pdf
It highlights that "Since HP had independently-developed page layout analysis technology that was used in products, (and therefore not released for open-source) Tesseract never needed its own page layout analysis. Tesseract therefore assumes that its input is a binary image with optional polygonal text regions defined."
This type of task can be performed by OpenCV and the resulting image handed off to Tesseract. You can find a sample of this type of code in the Git repo: https://github.com/Itseez/opencv_contrib/tree/master/modules/text/samples
The samples use Tesseract APIs to do image to text conversion.
