With this plugin you can extract the text of image attachments. It will create an annotation document next to the image document. This will contain a link to the image and the extracted text.
If you search for text that is part of the image, it will yield the annotation document.
Note: The process of extracting the text from the image is not done locally, but via an online API. The service stores the image on its servers only as long as necessary for the text extraction. However, if this is a dealbreaker for you, see Alternatives.
See https://forum.obsidian.md/t/basic-ocr-in-obsidian/18087
Advantages:
- runs locally on your machine
Disadvantages:
- runs locally on your machine
- probably slower
- probably worse results