Image forming apparatus suitable for recycling sheets of paper with images formed thereon, and method and program product for adding recycling information

1. An image forming apparatus, comprising:

an image data acquiring portion to acquire image data;

a recycling information determining portion to determine recycling information corresponding to said image data, said recycling information including a recycling class of said image data, said recycling information determining portion including a recycling class determining portion to determine the recycling class according to at least a comparison of a color ratio of said image data to a first threshold value and a comparison of a solid ratio of said image data to a second threshold value; and

an image forming portion to form an image of said image data on a sheet of paper together with said recycling information.

2. An image forming apparatus according to claim 1 , further comprising an accepting portion to accept an input of the recycling class,

wherein said recycling information determining portion determines said accepted recycling class as said recycling information, preceding said recycling class determined by said recycling class determining portion.

3. An image forming apparatus according to claim 1 , further comprising:

a position accepting portion to accept a designation of a position where said recycling information is imaged on a sheet of paper; and

an adding portion to add said recycling information to said image data in a manner that said recycling information is imaged at said designated position.

4. An image forming apparatus according to claim 1 , wherein said image data includes at least two pages of data, and

said recycling information determining portion determines a single piece of recycling information from the two pages of data that is to be imaged on both sides of a sheet of paper by said image forming portion in the duplex printing mode where an image is formed on both sides of a sheet of paper.

5. An image forming apparatus according to claim 4 , further comprising an adding portion to add said determined recycling information to the page data of front and back pages, respectively, that is to be imaged on both sides of the sheet of paper by said image forming portion.

6. An image forming apparatus according to claim 4 , further comprising an adding portion to add said calculated recycling information to the page data that is to be imaged on one side of the sheet of paper by said image forming portion.

7. An image forming apparatus according to claim 1 , wherein

said image data includes multiple pages of data, and

said recycling information determining portion includes

a page recycling information determining portion to determine the recycling information for each page data of said multiple pages of data, and

an image data recycling information determining portion to determine a single piece of recycling information for said image data, according to said recycling information determined for each page data of said multiple pages of data by said page recycling information determining portion.

8. An image forming apparatus according to claim 7 , further comprising an adding portion to add said determined recycling information to at least one of said multiple pages of data.

9. An image forming apparatus according to claim 1 , further comprising a back paper recycling information acquiring portion to acquire the recycling information of an image which is previously formed on a sheet of paper on which said image data is to be formed, wherein

said recycling information determining portion includes a back paper recycling information determining portion to determine new recycling information from said acquired recycling information and said determined recycling information.

10. An image forming apparatus according to claim 9 , wherein said back paper recycling information acquiring portion includes a recycling information reading portion to read the recycling information of the image that is previously imaged on the sheet of paper on which said image data is to be formed.

11. An image forming apparatus according to claim 9 , wherein said back paper recycling information acquiring portion includes a recycling information reading portion to read the recycling information that is previously stored corresponding to the sheet of paper on which said image data is to be formed.

12. An image forming apparatus according to claim 1 , further comprising

a bar code converter to convert the recycling information of said image data into bar code, and

an adding portion to add said bar code to said image data.

13. An image forming apparatus according to claim 1 , further comprising a embedding portion to embed said determined recycling information in said image data as a watermark.

14. An image forming apparatus, comprising:

an image data acquiring portion to acquire image data;

an image forming portion to form an image of said image data on a sheet of paper having a memory which is capable of recording the data in a nonvolatile manner;

a recycling information determining portion to determine recycling information corresponding to said image data, said recycling information including a recycling class of said image data, said recycling information determining portion including a recycling class determining portion to determine the recycling class according to at least a comparison of a color ratio of said image data to a first threshold value and a comparison of a solid ratio of said image data to a second threshold value; and

a writing portion to write said determined recycling information to said memory in the sheet of paper on which said image data is to be formed.

15. A method of adding recycling information, comprising the steps of:

acquiring image data;

determining recycling information corresponding to said image data, said recycling information including a recycling class of said image data, said recycling class being determined according to at least a comparison of a color ratio of said image data to a first threshold value and a comparison of a solid ratio of said image data to a second threshold value; and

forming an image of said image data on a sheet of paper together with said recycling information.

16. A non-transitory computer readable recording medium having a computer program stored thereon which, when executed, causes a computer to execute the steps of:

acquiring image data;

determining recycling information corresponding to said image data, said recycling information including a recycling class of said image data, said recycling class being determined according to at least a comparison of a color ratio of said image data to a first threshold value and a comparison of a solid ratio of said image data to a second threshold value; and

forming an image of said image data on a sheet of paper together with said recycling information.

17. An image forming apparatus, comprising:

an image data acquiring portion to acquire image data;

a characteristic data calculating portion to calculate characteristic data indicating a characteristic of said image data, wherein said characteristic data is calculated according to at least a comparison of a color ratio of said image data to a first threshold value and a comparison of a solid ratio of said image data to a second threshold value;

a recycling class determining portion to determine a recycling class according to said calculated characteristic data;

a back paper recycling information acquiring portion to acquire a recycling information of an image which is previously formed on a sheet of paper on which said image data is to be formed;

a recycling information determining portion to determine new recycling information from said determined recycling class and said acquired recycling information; and

an image forming portion to form an image of said image data on a sheet of paper together with said new recycling information.

18. An image forming apparatus according to claim 17 , wherein said back paper recycling information acquiring portion includes a recycling information reading portion to read the recycling information of the image that is previously imaged on the sheet of paper on which said image data is to be formed.

19. An image forming apparatus according to claim 18 , wherein said back paper recycling information acquiring portion includes a recycling information reading portion to read the recycling information that is previously stored corresponding to the sheet of paper on which said image data is to be formed.