Manga OCR: refer to the readme for installation ("m" key)
EasyOCR: refer to the readme for installation ("e" key)
RapidOCR: refer to the readme for installation ("r" key)
Apple Vision framework: this will work on macOS Ventura or later. In my experience, the best of the local providers for horizontal text ("a" key)
WinRT OCR: this will work on Windows 10 or later if winocr (pip install winocr) is installed. It can also be used by installing winocr on a Windows virtual machine and running the server (winocr_serve), installing requests (pip install requests) and specifying the IP address of the Windows VM/machine in the config file (see below) ("w" key)

Cloud providers

Google Lens: Google Vision in disguise (no need for API keys!), however it needs to download a couple megabytes of data for each request. You need to install pyjson5 and requests (pip install pyjson5 requests) ("l" key)
Google Vision: you need a service account .json file named google_vision.json in user directory/.config/ and installing google-cloud-vision (pip install google-cloud-vision) ("g" key)
Azure Computer Vision: you need to specify an api key and an endpoint in the config file (see below) and to install azure-cognitiveservices-vision-computervision (pip install azure-cognitiveservices-vision-computervision) ("v" key)

Usage

It mostly functions like Manga OCR: https://github.com/kha-white/manga-ocr?tab=readme-ov-file#running-in-the-background However:

it supports reading images and/or writing text to a websocket when the -r=websocket and/or -w=websocket parameters are specified (port 7331 by default, configurable in the config file)
it supports capturing the screen directly with -r screencapture. It will default to the entire first screen every 3 seconds, but a different screen/coordinates/window/delay can be specified in the config file
you can pause/unpause the image processing by pressing "p" or terminate the script with "t" or "q"
you can switch OCR provider with its corresponding keyboard key (refer to the list above). You can also start the script paused with the -p option or with a specific provider with the -e option (refer to owocr -h for the list)
holding ctrl or cmd at any time will pause image processing temporarily
for systems where text can be copied to the clipboard at the same time as images, if *ocr_ignore* is copied with an image, the image will be ignored
optionally, notifications can be enabled in the config file to show the text with a native OS notification
idle resource usage on macOS and Windows when reading from the clipboard has been eliminated using native OS polling
a config file (to be created in user directory/.config/owocr_config.ini, on Windows user directory is the C:\Users\yourusername folder) can be used to configure the script, as an example to limit providers (to reduce clutter/memory usage) as well as specifying provider settings such as api keys etc. A sample config file is provided here

Acknowledgments

This uses code from/references these projects:

Manga OCR
ocrmac for the Apple Vision framework API
NadeOCR for the Google Vision API
ccylin2000_lipboard_monitor for the Windows clipboard polling code

Thanks to viola for working on the Google Lens implementation!