On development or HTML conversion of web pages, often I have to copy too many text from designer’s mock-up files. Normally the mock-up files are images for client to realize the elements of web pages and design aspects.
To copy text on images, recently I have found a nice project & browser extension.
Note : If the images are background property of the element, we have to open that image in a tab to get the text. Also if there is fancy fonts, there will be chance for errors in spelling.