Translate any English text on your display with Screen Translator
Translation services from Google, Bing and others mean it's now very easy to translate plain text, and there are a host of apps and browser extensions available to simplify the process further. Translating text embedded in an image requires a little more work, but Screen Translator is an open source tool which may be able to help.
Installation is trickier than it should be, thanks to a setup program which lists some options in English, others in Cyrillic. It's not the most impressive start, but choose to install everything (which is safe, there's no adware here) and setup proceeds with no other problems.
Once Screen Translator is running, you can initiate a screen capture with a customizable hotkey, or by right-clicking Screen Translator's system tray icon and selecting "Capture". The mouse cursor changes, and you simply click and drag to draw a rectangle around your source text.
Release the mouse cursor and Screen Translator uses the Tesseract OCR engine to extract any text, sending the results to Google for translation. Finally, the source and translated text is displayed in a window, and you can copy it to the clipboard for reuse elsewhere.
One very obvious limitation here is that Screen Translator only supports English as a source language (you can't translate from another language to English). The Settings dialog does provide an option to choose the "Recognition language", though; it only lists English right now, but presumably that means other languages will be supported soon.
Another irritation is that you can only choose source languages by their two character ISO 639-1 codes, which aren't even sorted into alphabetical order. And so instead of the full name of the country, or language, you're trying to figure out what codes like IS, HR and TL represent. (If you're not sure, then as ever, Wikipedia reveals all.)
Screen Translator isn't the most powerful or convenient of translation tools. It could be significantly improved with just a little more work, though. And even now, if you’re happy translating from English only, the core of the program works well, delivering accurate and reliable results.