I have photographed text and writing with usual camera. Picture contains black printing lines and blue pen writing.
Picture contains the following artifacts:
1) paper is not white
2) non-uniform shading over paper
3) irregular paper pattern
Are there conventional ways to enhance such an images automatically? I wish paper to become uniformly white, without pattern, printing will be close to perfect black and writing close to perfect blue.
If you can keep consistent lighting in the photographs, for example, by having the same light point at the table and place the camera somewhere so you know you can always shoot the image in the same conditions, you could record Curves or Levels Action to do this (I would suggest Curves, since you want to have pretty exact results.) Then you could just open up all the images, use Batch.. and apply the recorded Action to the images.
If you're not familiar with Curves, I suggest you take a look at this tutorial, it covers the effect pretty well.
http://psd.fanextra.com/tutorials/professional-retouching-tutorial-using-curves-in-photoshop-part-3/
Heres a video about recording Actions:
http://video.about.com/graphicssoft/Quick-Tip--How-to-Record-and-Save-Actions-in-Photoshop-CS6.htm
Heres nice little tutorial on how to use Batch:
http://www.dummies.com/how-to/content/how-to-batch-process-actions-in-photoshop-cs6.html
So, you just combine these three with the premise that your photos actually have similiar color values to begin with (even if they vary a little, your results might be acceptable) and you're done.
