Make document photo printer friendly

Question

Students often use their cell phone camera to make copies of each others' notes and then they come to me to print them. Printing such images as is would be a waste of toner. Removing the perspective and adjusting colors to have real white background is time consuming. They usually cannot do it and I usually don't want to do it for them. They also don't like when I tell them that the price is multiplied by three if I print the photos as they are. (The service is non-profit.)

Is there any desktop application (Win7) or GIMP plugin or online service that can do this specific task automatically?

Usual image properties: The A4 document is on the floor, or on a table. Pure white paper (or patterned paper) has writing on it with pen. Sometimes it is a photo of a printed PDF (Yeah!). Sometimes they use red and blue and black pen on the same page. The lighting is usually not horrible (but sometimes they make it in a pub using flash).

(Don't mind the poor resolution of the sample image, they are usually better.)

Sample of a document made with cell phone camera:

Sample output after processing (approximate limit of my manual powers):

Answer 1

I used Microsoft's free Office Lens on your example image and it converted it to the image below in under 1 second. This is a standalone application intended for use with cameras and scanners although it will also import existing images.

It seems this is only available for Windows 10 (and Android and iPhone) so I don't know if it meets your requirement. It does not require the rest of Office to be installed although it integrates with other Office software such as OneNote if you have it.

Perhaps you could encourage your Students to do the job themselves on their phones using Office Lens or competing apps such as CamScanner?