GB2275843A

GB2275843A - Apparatus for digital archiving and retrieval of color images

Info

Publication number: GB2275843A
Application number: GB9326494A
Authority: GB
Inventors: Avraham Bachar
Original assignee: Scitex Corp Ltd
Current assignee: Scitex Corp Ltd
Priority date: 1993-03-04
Filing date: 1993-12-29
Publication date: 1994-09-07
Also published as: GB9326494D0

Abstract

Apparatus for digital archiving and retrieval of color images including a workstation, a storage device including at least one storage medium, apparatus responsive to control commands from said workstation for archiving and retrieval of color image digital information in an output independent RGB format, and data processing apparatus responsive to control commands from the workstation for providing a digital output dependent CMYK representation of said digital information. <IMAGE>

Description

FIELD OF THE INVENTION The present invention relates to archiving and retrieval methods generally and more particularly to color image archiving and retrieval in digital form.

BACKGROUND OF THE INVENTION Various types of archiving systems are known in the prepress industry for color image archiving. Usually, these systems include a storage medium such as an optical disk jukebox, a workstation and a computer which serves as a file server.

Examples of such systems include a system sold under the trade mark Scitex Manager, manufactured by Scitex Corporation Ltd., Herzlia, Israel and a system sold under the trade mark DB-580, manufactured by Dainippon Screen Mfg. Corporation Ltd. of Kyoto, Japan. The systems mentioned hereinabove operate without regard to the format of digital representation, e.g. CMYK and RGB, in which a color image is represented.

Desktop publishing software packages, such as those sold under the trade mark Adobe Photoshop, receive data in either RGB or CMYK format and convert data between the two data formats.

The desired output data format and quality of a color scanner is selected with reference to the desired final printed output, e.g. whether the desired color image is intended to be printed in a high quality magazine or in a newspaper. In some cases, the format of the digital representation of a color image is the RGB format since this format is more efficient in terms of disc storage space.

For example, US Patent 4,642,680 to Yamada describes an output dictated system where a scanned image is represented in a RGB format and the data is enlarged or reduced to its final size before image storage and conversion to a desired CMYK format.

SUMMARY OF THE INVENTION The present invention seeks to provide an improved digital image archiving and retrieval system.

The present inventor has appreciated that a major drawback of the above-described systems for data archiving, retrieval and conversion between RGB and CMYK is that the digital representation of a color image is not in an output independent format. The term "output independent format" refers throughout the specification and claims to a format which is an optimized digital representation of an original color image for the storage and retrieval of a digital representation of the color image. In the prior art described hereinabove the selection of a particular RGB representation of a color image is output dependent, i.e it refers to the desired printed output of the color image.

It is a purpose of the present invention to provide apparatus for digital archiving and retrieval of color images in an output independent RGB format, including apparatus for conversion of digital information in output independent RGB format to an output dependent CMYK representation of that digital information.

There is thus provided according to a preferred embodiment, of the present invention a system for digital archiving and retrieval of color images comprising a workstation, a storage medium, and apparatus responsive to control commands from a workstation, for archiving and retrieval of color image digital information in output independent RGB format.

Further, according to a preferred embodiment of the present invention there is provided data processing apparatus responsive to control commands from the workstation for providing an output dependent CMYK representation of the digital information.

The apparatus for archiving and retrieval of color image digital information in output independent RGB format is preferably operative to compress and decompress the digital information in output independent RGB format.

Additionally, the digital information in output independent RGB format may be labeled, identified, and displayed on a workstation.

The data processing apparatus preferably include apparatus for resolution determination, and apparatus for sharpness modification of the digital information in output independent RGB format.

Additionally, the data processing apparatus preferably include apparatus for selecting a desired LUT (look up table) according to a desired CMYK output.

The CMYK output of the digital information in output independent RGB format may be displayed on a display monitor, plotted or stored on a storage medium.

Additionally, the apparatus may include a color image scanner comprising a workstation, color separation sensing apparatus responsive to control commands from the workstation for providing digital information in an output independent RGB format of a color image, and a storage medium for storing the digital information in an output independent RGB format thereon.

The digital information in an output independent RGB format may be optimized by selecting an optimized scanning resolution.

Further, the scanner may include apparatus for tone reproduction of the optimized representation of the digital information in the output independent RGB format.

Additionally, the apparatus preferably include apparatus for receiving the optimized representation of the digital information in the output independent RGB format from the color scanner.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more fully understood and appreciated from the following detailed description, taken in conjunction with the drawing in which: Fig. 1 is a simplified block diagram illustration of an archival and retrieval system operating in accordance with a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS Reference is now made to Fig. 1 which is simplified illustration of apparatus 10 for digital archiving and retrieval of color images in accordance with a preferred embodiment of the present invention. The apparatus 10 preferably comprises a storage device 12 which includes at least one storage medium such as an optical jukebox. Data is stored on the storage medium of storage device 12 in an output independent RGB format.

The storage device 12 is accessible by a file server 14, such as a Micro Whisper, manufactured and sold by Scitex Corporation Ltd. of Herzlia, Israel. Interfacing with the file server is an interactive workstation 16, such as the Scitex Prisma, manufactured and sold by Scitex Corporation Ltd. of Herzlia, Israel.

File server 14 preferably includes an archive managing program such as Scitex Manager, manufactured and sold by Scitex Corporation Ltd. of Herzlia, Israel operating on a CPU.

Workstation 16 operates on the data stored in the storage medium 12 via file server 14.

File server 14 preferably includes a function allowing it to compress digital information stored in the storage medium 12 in output independent RGB format. The file server preferably also includes a decompression function operating on the compressed data.

File server 14 preferably also includes a function allowing it to label digital information in output independent RGB format, and also includes a function allowing it to recognize the digital information in output independent RGB format. The file server preferably also includes a function allowing it to display the output independent data on the monitor of workstation 16. All of the above functionalities are provided by the aforesaid Scitex Manager program.

Data processing apparatus 18 responsive to control commands from workstation 16 receives digital information in an output independent RGB format from the file server 14 and provides an output dependent CMYK representation of the output independent RGB data.

Data processing apparatus 18 scans the digital output independent RGB data. According to a set of control commands given by a user via workstation 16, the following operations are preferably performed on the scanned data: resolution determination, adaptive sharpening, color determination and output data format determination according to a desired output dependent CMYK digital representation of the output independent RGB data.

U.S. Patent 5,111,308 to the present applicant which is incorporated herein by reference, describes inter alia a series of electronic cards which are constructed and operative to perform the operations of data processor apparatus 18. Briefly, these are an input card, and an interpolation card which form the resolution determination circuitry.

The output of the resolution determination circuitry in a RGB format is supplied to a lines memory card and a sharpening card which form the adaptive sharpening circuitry.

The output in a RGB format of the sharpening circuitry is supplied to a color determination circuitry including a 3 dimensional look up-table card for converting the data in the RGB format to data in a CMYK format. The output of the 3 dimensional look up-table card is supplied to an output card which determines the final format of the desired output dependent CMYK data.

The above mentioned cards are illustrated in Fig. 5 of U.S. 5,111,308 in the sequence described hereinabove and in great details in net lists appearing as Annexes A4, All, A5, A6, A7 and A8 in U.S. Patent 5,111,308.

Data processing apparatus 18 preferably interfaces with a laser plotter 20, such as a Raystar, manufactured and sold by Scitex Corporation Ltd. of Herzlia, Israel. Laser plotter 20 produces halftone film color separations 22 which are employed in a conventional process color printing press 24.

According to another preferred embodiment of the present invention the data processing apparatus 18 interfaces with a display monitor 26, or with a storage medium 28, or both.

An output independent RGB digital representation of a color image is preferably obtained using a color scanner 30, such as a system manufactured and sold under the trade mark Smart Scanner by Scitex Corporation Ltd., of Herzlia, Israel.

Preferably, an optimized output independent RGB representation of a color image is obtained by selecting an optimal resolution of the color scanner 30 by an operator via a control workstation 32. Further optimization of the digital information in output independent RGB format is obtained by tone reproduction performed using control commands via workstation 32.

The ;gital information in output independent RGB format is stored on a storage medium 34. According to one preferred embodiment of the present invention storage medium 34 can be transferred to the storage device 12.

According to another preferred embodiment of the present invention the storage device 34 is connected with file server 14.

It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the invention is defined only by the claims which follow:

Claims

CLAIMS 1. A system for digital archiving and retrieval of color images comprising: a workstation; a storage device including at least one storage medium; apparatus responsive to control commands from said workstation for archiving and retrieval of color image digital information in an output independent RGB format; and data processing apparatus responsive to control commands from the workstation for providing a digital output dependent CMYK representation of said digital information.
2. A system according to claim 1 wherein said apparatus for archiving and retrieval of color image digital information in an output independent RGB format is operative to compress said digital information.
3. A system according to claim 1 wherein said apparatus for archiving and retrieval of color image digital information in an output independent RGB format is operative to decompress said digital information.
4. A system according to claim 1 wherein said apparatus for archiving and retrieval of color image digital information in an output independent RGB format is operative to label said digital information.
5. A system according to claim 1 wherein said apparatus for archiving and retrieval of color image digital information in an output independent RGB format is operative to identify said digital information.
6. A system according to claim 1 wherein said apparatus for archiving and retrieval of color image digital information in an output independent RGB format is operative to display a color image representation of said digital information on said workstation.
7. A system according to claim 1 wherein said data processing apparatus comprises apparatus for determining the resolution of said digital information in an output independent RGB format.
8. A system according to claim 1 wherein said data processing apparatus comprises apparatus for modifying the sharpness of said digital information in output independent RGB format.
9. A system according to claim 1 wherein said data processing apparatus comprises apparatus for selecting a desired LUT (look up table) according to a desired output dependent CMYR representation of said digital information.
10. A system according to claim 1 including apparatus for displaying said output dependent CMYK representation of said digital information on a display monitor.
11. A system according to claim 1 including apparatus for plotting said output dependent CMYK representation of said digital information.
12. A system according to claim 1 including apparatus for storing said output dependent CMYK representation of said digital information on a storage medium.
13. A system according to claim 1 including a color image scanner comprising: a workstation; color separation sensing apparatus responsive to control commands from said workstation for providing digital information in an output independent RGB format of a color image; and a storage medium for storing said digital information in an output independent RGB format thereon.
14. A system according to claim 13 including apparatus for selecting an optimized scanning resolution to obtain an optimized representation of said digital information in an output independent RGB format.
15. A system according to claim 14 apparatus for tone reproduction of said optimized representation of said digital information in an output independent RGB format.
16. A system according to claim 15 including apparatus for storing said optimized representation of said digital information in an output independent RGB format on said storage medium.
17. A system according to claim 1 including apparatus for receiving said optimized representation of said digital information in output independent RGB format from said color image scanner.
18. A system for digital archiving and retrieval of color images substantially as hereinbefore described with reference to the accompanying drawing.