How to Implement Ocr on a Website Using PHP

How can I implement OCR on a website using PHP?

Since you're on a Linux box, I would highly recommend Google's open source project ocropus.

It's not PHP, but I think it will be your best option. Of course you can call it from within PHP via exec. Its mature and has a lot of options. From the project site:

The OCRopus engine is based on two research projects: a high-performance handwriting recognizer developed in the mid-90's and deployed by the US Census bureau, and novel high-performance layout analysis methods.

There is also another open source project, tesseract. I've used this in the past as well and have been pleased with the results. Includes training, limiting your alphabet, etc.

Does anyone know a working OCR (PHP)?

I don't believe anybody implemented any OCR solution in PHP.
OCR ( Optical Character Recognition ) is a very complex piece of Software and not anything PHP would be suited for to implement.

But for sure you can call an external OCR program from PHP.
So you should look for an OCR solution which can be used from command line.

Converting an image to text via Javascript or PHP?

Yes, this is called Optical Character Recognition (OCR) and there are lots of libraries available for most languages.

Does anyone know a working OCR (PHP)?
How can I implement OCR on a website using PHP?

Read text from an image with PHP

The process you are looking for is called Optical Character Recognition.

http://en.wikipedia.org/wiki/Optical_character_recognition

There is a package available, called phpOCR, that does exactly what you need.

http://sourceforge.net/projects/phpocr/

Is there any technique to convert a image in to real text which is copyable

The technique is called optical character recognition (OCR). I don't like to simply suggest a search, but that's probably your best bet here.