JP2002218222A - Device for burying image information in image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device with which image quality is maintained and image information is transmitted together with image data. SOLUTION: By one performance form of this invention, the image information is buried in images in the form of an 'electronic watermark'. By using an optional one of a plurality of electronic watermark techniques, image processing information is buried in the images. When the images are outputted to the other device, the electronic watermark is performed from the image data and decoded by the device and then output is performed so as to maintain the image quality by utilizing it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for embedding image information in an image, the image information being later extracted and decoded from the image and ensuring that the image quality is not degraded by subsequent processing or manipulation of the image. Used to

[0002]

2. Description of the Related Art Members of the color and image processing industry seek to find a suitable technique for communicating image processing information describing the manner in which an image has been preprocessed in order to ensure that subsequent processing of the image does not degrade. I've been working for a long time. For example, if the image is already sharpened, it is useful for the printer driver to know about this preprocessing because further sharpening may cause artifacts in the printed image. Currently, if image pre-processing information is communicated, it is often communicated independently of the image data, either as part of a file format, or perhaps as an intra-application communication. Image processing information is sometimes communicated separately from the image data in the default form of the operating system.

[0003] Using the above techniques, the devices subsequently used to transform or manipulate the image data must be able to recognize and decode the image processing information, regardless of the manner in which it is transmitted. Otherwise, the device cannot use the image processing information when processing the image data. If the image processing information is not available or cannot be recognized and decoded, any further processing that occurs may degrade image quality. If the image processing information can be transmitted as part of the image itself, ie as image data, the problems associated with recognizing and decoding the information are avoided, thus ensuring good image quality.

[0004] Often, no image processing information is communicated to any device that intends to manipulate or convert the image. For example, when the printer driver receives an image print request,
Generally, a printer driver cannot obtain information on image quality, that is, information on whether or not halftoning, scaling, sharpening, gamma correction, and the like have been performed. When this type of image processing information is provided to the printer driver, the rendering intent can be identified and the image can be printed with more pleasing results for the user.

[0005] Digital watermarks are used to protect copyrights.
It was developed by the electrophotographic industry to indicate the source of the image. A unique watermark is embedded in the image data identifying the image source. Advantageously, the use of digital watermarking, or some other technique that can embed image processing information in an image, makes it possible to use the information embedded later, before or during a subsequent image processing operation. . Various digital watermarking techniques are described in U.S. Patent No. 6,078,664, which is hereby incorporated by reference in its entirety.
No. 5,905,800, 5,889,868
No. 5,822,432, 5,745,569
No. 5,687,236, No. 5,613,004
No. 5,539,735 and 5,428,6
No. 06.

[0006]

Accordingly, there is a need for a method and apparatus that allows image information to be transmitted with image data so that image quality is preserved.

[0007]

According to the present invention, the image information is
A method and apparatus for embedding image information in an image so that one or more devices that later process the image can be used. Utilizing this image information for subsequent image processing tasks performed by other devices can ensure satisfactory image quality.

According to a preferred embodiment of the present invention, the image information is embedded in the image in the form of a “digital watermark”. Image processing information can be embedded in an image using any one of a plurality of digital watermarking techniques. When the image is subsequently output to another device, the device can extract the watermark from the image data, decode it, and use it to ensure that the image quality is preserved. The embedded image information may relate to pre-processing tasks performed on the image data, rendering intents, or any other information related to maintaining image quality. For example, the device can use the watermark to determine whether the image has been previously halftoned, scaled, sharpened, gamma corrected, or the like.

Other features and advantages of the invention will be apparent from the description and drawings, and from the claims.

[0010]

DETAILED DESCRIPTION Most common image formats, such as JPEG and FlashPix, have a comment / header field that can hold information identifying the image source. Tools for converting and manipulating images must conform to predefined conventions that ensure that comment information is preserved. However, in a graphics design environment, it is difficult to ensure that comment information is retained, as each designer tends to use his or her favorite tools.

One advantage of using digital watermarking to convey prior image processing information is that the tools used to manipulate or convert the image need not maintain the comment field of the image. As a result, embedding image processing information about image processing that has already been performed using digital watermarks allows the designer to use whatever tools he or she desires for subsequent image processing. Furthermore, the techniques commonly used to perform digital watermarking do not require that the watermarking scheme be resistant to malicious deliberate attacks, but only withstand the normal image manipulations that graphic designers typically perform. . Another advantage is that the watermark can be removed before processing if the watermark can be detected, and later reapplied with additional processing information if the file is saved, printed or shared.

The present invention also applies to embedding information other than preceding processing information, such as rendering intents, in image data, however, with respect to the method and apparatus of the present invention, one or more other apparatuses may be used later. The following mainly describes embedding of available preceding processing information. For example,
The information to be embedded can later be used to ensure that the image quality is not degraded by subsequent image processing. Those skilled in the art will appreciate that the method and apparatus of the present invention allow any information associated with an image to be embedded in the image data, and subsequently extracted and decoded therefrom.

FIG. 1 is a block diagram illustrating an exemplary embodiment of an apparatus incorporating the method and apparatus of the present invention;
For purposes of illustration, assume a digital camera. The device of the present invention can be any type of device that acquires an image of an object and stores the image in a digital format, such as a scanner or an optical character recognition (OCR) device. The digital camera 1 includes a processor 10 and a system bus 11 for executing the method of the present invention,
Operating system code 3 for camera 1,
And an embedding algorithm code 4 for executing a task of embedding preceding image processing information in an image captured by the camera 1, and a storage device 2 for storing an image processing algorithm 5 and the like. The storage device 2 may also be used to store image data and code associated with other processing algorithms (eg, sharpening) performed by the processor 10.

The camera 1 has a display device 8 and includes an image acquisition component 6 and an image download component 7. The image acquisition component 6 is an input device 9 that causes the processor 10 to execute an image acquisition routine.
An image is captured in response to a user command input via the. The image download component 7 can link to some other device such as the printer shown in FIG. 2 and transfer the image captured by the camera 1 to the device. For purposes of illustration, the device, which is assumed to be a printer 15, extracts pre-processing information from the image downloaded to it and, if necessary or desired, utilizes the pre-processing information to recognize the rendering intent. I do.
Next, the printer 15 uses this information when printing an image to guarantee the image quality.

According to a preferred embodiment of the present invention, the image transferred from the device 1 to the printer 15 is embedded with the preceding image processing information by utilizing one of a plurality of watermarking techniques. Printer 15 also includes a processor and storage such as shown in FIG. Therefore,
When the processor of the printer 15 executes the extraction / decoding algorithm of the present invention, the digital watermark of the transmitted image is extracted and decoded. The image processing information included in the digital watermark can then be used to ensure that the printer 15 does not degrade the quality of the image due to any subsequent processing and / or printing of the image.

The components of the digital camera 1 and the printer 15 and their functions are well known. Accordingly, a detailed discussion of these components and the manner in which the embedding, extracting / decoding algorithms of the present invention can be configured to perform is not provided herein. One skilled in the art will appreciate the manner in which suitable devices, such as those shown in FIGS. 1 and 2, may be configured to perform each task in accordance with the present invention.

FIG. 3 is a flowchart illustrating a method 20 of the present invention for embedding prior image processing information in an image according to a preferred embodiment. Block 21: The image is captured and digitized. Block 23: The digitized image is stored in the storage device. Block 25: Digital image data is read from the storage device. Block 27: Processed according to one or more image processing algorithms. Block 29: The processed image is then stored in storage. Block 31: It is determined whether all image processing has been completed. Block 33: The processed image is read from the storage device, and image processing information related to the executed image processing is embedded in the processed image. The details will be described below. As indicated by block 21, the image is captured and digitized. Next, as indicated by block 23, the digitized image is stored in a storage device. Before storing the digital image data in the storage device, some digital image data processing may be performed (not shown). If the digital image data is to be processed by one or more image processing algorithms, such as, for example, a scaling or sharpening algorithm, the digital image data is read from storage, as shown in block 25, and as shown in block 27. To
Processed accordingly. This is done one or more times, depending on the type and amount of processing performed on the image. The processed image is then stored in the storage device 2, as indicated by block 29.

According to the present invention, processor 10 tracks image processing performed on a digital image. When all image processing is complete, as indicated by the decision made at block 31, as shown at block 33,
The processed image is read from the storage device, and image processing information related to the executed image processing is embedded in the processed image. As described above, it is preferable to use a digital watermark method for embedding processing information in an image. Digital watermarking is well known in the image processing field. In order to embed the image processing information in the image data, various electronic watermarking techniques such as those described in the above patents can be used. Those skilled in the art will appreciate that watermarking techniques suitable for performing this function are available.

The digital watermark utilized may include a bit that identifies each processing technique performed, or only the processing technique associated with the device that will continue to receive the image. FIG. 3 also shows a case where the pre-processing information is transmitted by a digital watermark, but other types of information such as a rendering intent or any other information related to image quality retention are also transmitted by the digital watermark. Note also that this can be done.

FIG. 4 is a flowchart illustrating a method of extracting information embedded in an image according to the extraction / decoding algorithm 40 of the present invention, such as the printer 15 shown in FIG.

Block 41: The image processing device receives the digital image in which the watermark is embedded. Block 43: Store in storage. Block 45: Read the digital image data from the storage device according to the extraction / decoding algorithm. Block 47: The watermark is extracted from the image data and decoded. Block 49: Image processing is performed using the extracted information. The details will be described below. As mentioned above, the device
Preferably, it comprises some type of processor and storage, such as that shown in FIG. Extraction /
The decoding algorithm code is stored and executed by the processor when it is called.

First, as shown in blocks 41 and 43, the device receives the watermarked digital image and stores it in storage. Next, block 45
As shown in (1), the extraction / decoding algorithm causes the image data to be read from the storage device. Next, as shown in block 47, the digital watermark is extracted from the image data and decoded so that the image processing device can understand and use it. As described above, the decoded information may include, for example, pre-processing information, rendering intent, or any other relevant information. Once the watermark is decrypted, the decrypted information is used by the image processing device in the above manner to ensure that image quality is preserved.

The embodiments of the present invention have been described in detail above. Hereinafter, examples of each embodiment of the present invention will be described.

(Embodiment 1) An apparatus (1) for embedding digital information in digital image data, comprising a processor (10), wherein the processor (10) embeds the digital information in digital image data by an embedding algorithm ( An apparatus (1), wherein the digital information can be subsequently used by a device (15) that can perform 4) and subsequently process the digital image data.

(Embodiment 2) The apparatus according to embodiment 1, wherein the digital information corresponds to a rendering intent.

(Embodiment 3) An apparatus according to embodiment 1, wherein the digital information describes a manner in which the digital image data was processed before being output to the device (15).

(Embodiment 4) The apparatus according to embodiment 1, wherein the digital information is embedded in the digital image data in the form of a digital watermark.

(Embodiment 5) The digital watermarking should be performed on the digital image data as required by the device (15) from which the digital image data is output from the device (1), or 5. The apparatus of embodiment 4, including a rendering intent to signal an image processing task that should not be performed.

(Embodiment 6) The digital watermark includes information describing the manner in which the digital image data was processed before being output from the device (1) to the device (15). The described device.

(Embodiment 7) A device (1) for embedding digital information including the following (a) and (b) in digital image data, (a) a storage device (2), and (b) a processor (10) The processor (10) can execute an embedding algorithm (4) for embedding the digital information in the digital image data, and the processor (10) can execute the embedding algorithm from the storage device (2). A device (15) for reading data, embedding the digital information in the digital image data, and subsequently processing the digital image data, can later use the digital information.

(Embodiment 8) Before executing the embedding algorithm (4), the processor (10) reads out the digital image data from the storage device (2), and executes at least one Performing two image processing tasks, storing the processed digital image data in the storage device (2), and tracking the image processing tasks performed on the digital image data;
When the processor (10) embeds the digital information in the digital image data, the digital information:
At least one made by the processor (10)
8. The apparatus of embodiment 7, comprising information related to one of said image processing tasks.

(Embodiment 9) A method (20) for transmitting digital information that can be used to maintain the quality of an image generated from the digital image data, comprising the following steps (a), (a): And (33) embedding the digital information in the digital image data, wherein a device that has received the digital image data in which the digital information is embedded later extracts and decodes the embedded digital information. The device (15) can use the extracted and decoded digital information.

(Embodiment 10) The method according to Embodiment 9, further comprising the following (b) and (c): (b) before the embedding step (33), the digital image data is subjected to one or more A step (27) of processing according to an image processing algorithm; and (c) a step (2) of the processing.
7) and before the embedding step (33),
Maintaining a record of any image processing algorithms (5) performed on the digital image data, wherein the embedded digital information is associated with at least one of the performed image processing algorithms (5). Include information to do.

It should be noted that the present invention has been described in terms of a preferred embodiment of the present invention. Those skilled in the art will appreciate that modifications can be made to the embodiments of the invention described herein and that all such modifications are within the scope of the invention. For example, while the present application specifically refers to patents that disclose various digital watermarking techniques suitable for use with the present invention, those skilled in the art will recognize other digital watermarking techniques or techniques disclosed in the above patents. It will be understood that variations may be suitable for use with the present invention. All such techniques are within the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a block diagram of a digital camera suitable for implementing the method and apparatus of the present invention for embedding image information in digital images captured by the camera.

2 is a pictorial diagram of a printer that can receive digital images captured by the camera shown in FIG. 1, extract and decode information, and make the information available for further processing of the digital image. .

FIG. 3 is a flowchart illustrating a method of the present invention according to a preferred embodiment for embedding preceding image information in an image.

FIG. 4 illustrates a method of the present invention according to a preferred embodiment used by an apparatus as shown in FIG. 2 to extract and encode image information and use the image information to ensure satisfactory image quality. It is a flowchart shown.

[Explanation of symbols]

 Reference Signs List 1 device for embedding digital information in digital data 2 storage device 3 operating system code 4 embedding algorithm 5 image processing algorithm 6 image acquisition component 7 image download component 8 display device 9 input device 10 processor 15 digital image data processing device

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Robert E. Sobol Illdale Drive, Fort Collins, Colorado, USA 2313 F-term (reference) 5B057 CE08 CE09 CG07 CH01 CH11 5C076 AA14 BA06

Claims (1)

[Claims] An apparatus for embedding digital information in digital image data, the apparatus comprising a processor, the processor being capable of executing an embedding algorithm for embedding the digital information in digital image data, followed by the digital image. Apparatus characterized in that the data processing equipment can later use said digital information.