Print Control Strip and Method of Preparing the Same

Abstract

A method of preparing a print control strip including at least two process control elements and being adapted to at least a width of at least one used area of at least one original image, includes determining borders of the at least one used area. A state is assigned to every process control element in dependence on if the process control element is located substantially inside the borders. A process control strip is created by using only process control elements that have been assigned a state as being inside the borders.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a diagrammatic plan view of an original image with two pages and print control strips; and

FIG. 2 is a plan view of an original image with pages and a reduced print control strip.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures of the drawings in detail and first, particularly, to FIG. 1 thereof, there are seen two pages 1, 2 which are included in an original image that is otherwise not further illustrated herein. These pages 1, 2 may include a wide variety of objects such as graphics, images, or text. The pages 1 and 2 are examples of used areas. They are not drawn to scale and are for illustration purposes only.

A print control strip 3 is disposed in a free area of the original image. Such a print control strip is usually located at a front edge or rear edge of the original image in relation to the print substrate to be printed.

The print control strip 3 includes measurement fields 4, 4′, 5, 5′ as process control elements. For reasons of clarity, these measurement fields are enlarged and not drawn to scale. They may be solid tone fields, halftone fields, register fields, or the like.

The pages 1, 2 of the original image are assigned borders 6, 7 and 8, 9. The dashed lines are the continuation of these borders 6, 7, 8, 9 in the area of the print control strip 3.

According to the prior art, the print control strip is chopped during page assembly based on the borders 6, 7 and 8, 9. Such a chopping reduces the print control strip 3 and the process control elements 4′ and 5′ are chopped and remain only in part. In a subsequent measurement to evaluate the print result, these process control element parts 4′ and 5′ may cause errors or at least confusion in a measurement system.

For a better understanding, example 1 illustrates a program routine for preparing a print control strip according to the prior art in the form of a pseudocode.

EXAMPLE 1

For all measurement fields of the strip
go to the position of the current measurement field
draw the measurement field
End of loop

That program routine is stored as a PostScript within an original image in the PostScript format.

It is a program loop that instructs for all process control elements of the print control strip, i.e. for all measurement fields of the strip to go to the position of the current measurement field, to draw the measurement field, and to prepare the next measurement field in a following execution of the loop.

In that manner, all measurement fields are initially drawn without considering a required chopping due to the used area. In the prior art, the RIP frequently knows where the used area is located, i.e. where the borders 6, 7, 8, 9 of the individual used areas are located. All image data that are outside those borders are not prepared. Thus the chopped fields described with reference to FIG. 1 are prepared.

FIG. 2 shows a reduced print control strip 3 that has been cut in accordance with the method of the invention and does not have any chopped off process control elements 4′, 5′. As shown in FIG. 1, more than a negligible part of the process control elements 4′ is located outside the borders 6, 7, 8, and 9. In accordance with the provisions of the present invention, these process control elements 4′ are thus not included when the print control strip 3 is prepared. In contrast, a small part of the process control elements 5′ extends beyond the borders 6 and 9. This small part is within the tolerance, which is 0.5 mm, in the given example. Consequently, the process control elements 5′ are assigned a state that describes that they are located within the borders 6, 7 and 8, 9. Thus these process control elements 5′ are included in the preparation of the print control strip 3. Process control elements 4′ protrude beyond the borders 7 and 8 to such an extent that their parts outside the borders are not within the tolerance. Consequently, they are assigned the state of being outside the borders. Thus they will not be used. The print control strip that is prepared in this way does not have any chopped measurement fields or process control elements 4′, 5′.

A pseudocode of an exemplary simplified program routine for preparing a print control strip in accordance with a method of the invention is given in Example 2:

EXAMPLE 2

For all measurement fields of the strip
a. go to the position of the current measurement field
check if the measurement field or parts of the current measurement
field are in the cut-off area,
if no:
draw the measurement field
if yes:
leave out the measurement field
End of loop

In this context, a loop is likewise to be executed. Initially, the first measurement field, i.e. a first process control element, is targeted. This measurement field is examined to find out whether parts of the process control element or measurement field are inside or outside the borders 6, 7 or 8, 9. Then the measurement field or process control element is assigned a state yes or no. Yes means that the process control element is outside the borders. No means that the process control element is inside the borders. Depending on the associated state, the process control element is drawn if its state is no and it is not drawn if the state is yes. This loop is executed for all process control elements of the print control strip 3.

This program routine may likewise be stored within a PostScript file of the original image. It may also be an embedded program function with in a PDF of an original image. In this case, the RIP opens the embedded program code and executes the process of preparing the print control strip. Suitable tolerances for assigning the states may be stored in a separate area of the program or may be provided directly in the RIP. Based on these tolerances, for the measurement fields 5′ assigned the state “no”, the measurement field is not located outside the borders 6, 7, 8, 9. A print control strip is generated that includes only complete process control elements 5, 5′ located substantially inside the orders 6, 7, 8, 9 of used areas of the original image. Confusion of the electronic measurement system due to chopped measurement fields is avoided.

Claims

1. A method of preparing a print control strip including at least two process control elements and being adapted to at least a width of at least one used area of at least one original image, the method comprising the following steps: determining borders of the at least one used area;assigning a state to each process control element in dependence on if the process control element is located substantially inside the borders; andcreating a process control strip using only process control elements having been assigned a state as being inside the borders.

2. The method according to claim 1, which further comprises defining the used area by the borders of at least one region selected from the group consisting of individual copy, individual page, width of subject, print sheet format, and printing master format.

3. The method according to claim 1, which further comprises assigning the states of the process control elements before the print control strip is prepared, and preparing the print control strip without the process control elements.

4. The method according to claim 3, which further comprises assigning the states to the process control elements by a raster image processor.

5. The method according to claim 1, wherein those process control elements that include areas located outside the borders of the used area up to a length of between 0.3 mm and 0.75 mm are assigned a state as being located inside the borders and are included in the creation of the print control strip.

6. The method according to claim 1, wherein those process control elements that include areas located outside the borders of the used area up to a length of 0.5 mm are assigned a state as being located inside the borders and are included in the creation of the print control strip.

7. The method according to claim 1, which further comprises: providing a program routine including instructions for recognizing the borders of the at least one used area, for assigning a state of being located inside or outside the borders to the process control elements; andtransferring data to a raster image processor for using process control elements having been assigned the state of being located inside the borders for a print control strip.

8. The method according to claim 7, which further comprises storing the print control strip within a program routine in the at least one original image.

9. The method according to claim 7, which further comprises storing both the print control strip and instructions in a program routine in the at least one original image.

10. The method according to claim 7, which further comprises embedding the program routines in an EPS or in the form of XObjects in a PDF including the at least one original image.

11. The method according to claim 7, which further comprises storing the program routines directly in the form of PostScript instructions if the at least one original image is provided as a PS file.

12. A print control strip prepared according to claim 1.