JP2006262162A - Image forming apparatus, system and method for printing image, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus, a system and a method for printing images, and programs, which can perform black and white outputs in one K color material for image data, such as that that a white board is color photographed, to save CMY color materials, and acquire clear and more appropriate printed images with less bleeding or scattering. <P>SOLUTION: The image forming apparatus has an image data color determination means 42 for determining whether an image file received from an image supply apparatus is photographed in color or black and white, and a printing mode determination means 43 for determining whether image data in the image file, which is determined to have been color photographed by the image data color determination means 42, is printed in color or black and white. In addition, the image forming apparatus also has an image conversion means 45 for converting the image data in the image file photographed in color, which is determined to be printed in black and white by the printing mode determination means 43, into a black and white image. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus, an image printing system, a program, and an image printing method for receiving an image file transferred from an image supply apparatus connected via an interface and printing image data in the image file.

  Conventionally, in order to print image data in an image file taken with a digital still camera, the image data is once loaded onto a personal computer (hereinafter referred to as a PC) and then loaded into an application software for image processing and editing if necessary. After that, printing was performed from a PC using a printer driver. Such conventional digital image printing requires data transfer to a PC and application software, and has never been easy.

  In recent years, a standard for a direct print system has been established in which an image file in a digital still camera can be directly printed out by connecting the digital still camera and the printer device without using a PC. Products that support the standard on both sides are becoming widespread (see, for example, Patent Document 1). According to such a digital still camera and a printer device in accordance with the standard of the direct print system, it is possible to directly transfer an image file from the digital still camera to the printer device without using a PC and perform printing.

  On the other hand, in a digital still camera, title and character information corresponding to a captured image can be recorded in the Exif header when the image is captured. For example, Patent Document 2 describes a digital still camera in which a character string related to an image is input on a digital still camera and stored in an Exif header of the image. The information embedded in the Exif header in this way is used for image management and retrieval on the PC.

JP 2004-064740 A JP 2003-224750 A

  By the way, color images such as landscapes and portraits taken with a digital still camera are generally output in color with a printer, but a monochrome document or a whiteboard at a meeting is taken with a digital still camera. In the case of a color image, it may be preferable to output in monochrome using a printer.

  More specifically, when a color image obtained by photographing a whiteboard or the like in a conference with a digital still camera is output in color by a printer device, gray is produced using a color material (CMYK or the like) of the printer device. Will be expressed. In this case, characters drawn on a whiteboard or the like are printed slightly thicker than in the case of outputting with one color of K color material as in monochrome output.

  The present invention has been made in view of the above. For example, for image data obtained by photographing a whiteboard in color, monochrome output of one K color material is possible, and CMY color materials can be saved. An object of the present invention is to provide an image forming apparatus, an image printing system, a program, and an image printing method that are capable of obtaining a more favorable print result image that can be printed with less blur and scattering.

  In order to solve the above-described problems and achieve the object, an image forming apparatus according to a first aspect of the present invention receives an image file transferred from an image supply apparatus connected via an interface, and receives the image file. In the image forming apparatus for printing the image data in the image data color determination means for determining whether the image file received from the image supply apparatus has been shot in color or monochrome, and the image data color determination means Print mode determining means for determining whether image data in an image file determined to be shot in color is printed in color or monochrome, and shooting in color determined to be printed in monochrome by the print mode determining means Image conversion means for converting the image data in the image file into a monochrome image.

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the image data color determination unit receives the image received from the image supply device based on photographing condition information embedded in the image file. Determine whether the file was shot in color or monochrome.

  According to a third aspect of the present invention, in the image forming apparatus according to the first aspect, the print mode determination unit receives the image file received from the image supply device based on shooting condition information embedded in the image file. It is determined whether the image data in the image is printed in color or monochrome.

  According to a fourth aspect of the present invention, in the image forming apparatus according to the first aspect, the print mode determination unit receives the image in the image file received from the image supply device based on the image data in the image file. Determine whether the data is printed in color or monochrome.

  According to a fifth aspect of the present invention, in the image forming apparatus according to the second or third aspect, the image file has an Exif (Exchangeable Image File Format) file format, and the shooting condition information is included in a header of the image file. Stored.

  According to a sixth aspect of the present invention, there is provided an image printing system having an interface between an image supply device capable of supplying an image file and an image forming device for printing image data in the image file transferred from the image supply device. In the image printing system connected via the image data color determination means for determining whether the image file received from the image supply device has been shot in color or monochrome, and the image data color determination means Print mode determining means for determining whether the image data in the image file determined to be printed in color or monochrome, and an image photographed in the color determined to be printed in monochrome by the print mode determining means Image conversion means for converting the image data in the file into a monochrome image.

  According to a seventh aspect of the present invention, in the image printing system according to the sixth aspect, the image data color determination means receives the image received from the image supply device based on photographing condition information embedded in the image file. Determine whether the file was shot in color or monochrome.

  According to an eighth aspect of the present invention, in the image printing system according to the sixth aspect, the print mode determining means receives the image file received from the image supply device based on photographing condition information embedded in the image file. It is determined whether the image data in the image is printed in color or monochrome.

  According to a ninth aspect of the present invention, in the image printing system according to the sixth aspect, the print mode determining means receives the image in the image file received from the image supply device based on the image data in the image file. Determine whether the data is printed in color or monochrome.

  According to a tenth aspect of the present invention, in the image printing system according to the seventh or eighth aspect, the image file has an Exif (Exchangeable Image File Format) file format, and the shooting condition information is included in a header of the image file. Stored.

  An image data color determination function for determining whether the image file received from an image supply apparatus connected via an interface is captured in color or monochrome, and A print mode determination function for determining whether image data in an image file determined to have been shot in color by the image data color determination function is printed in color or monochrome, and printing in monochrome by this print mode determination function Then, the computer is caused to execute an image conversion function for converting the image data in the image file photographed in the determined color into a monochrome image.

  According to a twelfth aspect of the present invention, in the program according to the eleventh aspect, the image data color determination function is configured so that the image file received from the image supply device is based on shooting condition information embedded in the image file. It is determined whether the image was shot in color or monochrome.

  According to a thirteenth aspect of the present invention, in the program according to the eleventh aspect, the print mode determination function includes a function in the image file received from the image supply device based on shooting condition information embedded in the image file. It is determined whether the image data is printed in color or monochrome.

  According to a fourteenth aspect of the present invention, in the program according to the eleventh aspect, the print mode determination function uses the image data in the image file received from the image supply device based on the image data in the image file. Determine whether to print in color or monochrome.

  The image printing method of the invention according to claim 15 is an image data color determination step for determining whether the image file received from the image supply device connected via the interface is captured in color or monochrome. A print mode determining step for determining whether the image data in the image file determined to have been photographed in color by the image data color determining step is to be printed in color or monochrome, and a monochrome in the print mode determining step. And an image conversion step of converting image data in an image file photographed in a color determined to be printed into a monochrome image.

  According to a sixteenth aspect of the present invention, in the image printing method according to the fifteenth aspect, the image data color determining step receives the image received from the image supply device based on photographing condition information embedded in the image file. Determine whether the file was shot in color or monochrome.

  According to a seventeenth aspect of the present invention, in the image printing method according to the fifteenth aspect, the print mode determining step receives the image file received from the image supply device based on photographing condition information embedded in the image file. It is determined whether the image data in the image is printed in color or monochrome.

  According to an eighteenth aspect of the present invention, in the image printing method according to the fifteenth aspect, in the printing mode determination step, the image in the image file received from the image supply device based on the image data in the image file. Determine whether the data is printed in color or monochrome.

  The invention according to claim 19 is the image printing method according to claim 16 or 17, wherein the image file is in an Exif (Exchangeable Image File Format) file format, and the shooting condition information is included in a header of the image file. Stored.

  According to the first aspect of the present invention, even if the image data is captured in color, if it is determined that the image is printed in monochrome, the image data captured in color is converted into a monochrome image. Thus, for example, for image data obtained by photographing a white board in color, monochrome output of one K color material is possible, so that the CMY color material can be saved and neat and less blurred and scattered. There is an effect that a suitable printing result image can be obtained. In addition, depending on the image forming apparatus, an effect of increasing the printing speed can be expected.

  According to the second aspect of the present invention, it is easy to determine whether the image file received from the image supply device is shot in color or monochrome based on the shooting condition information embedded in the image file. With this arrangement, it is possible to obtain a more suitable print result image.

  According to the invention of claim 3, it is determined whether to print the image data in the image file received from the image supply device in color or monochrome based on the shooting condition information embedded in the image file. As a result, it is possible to obtain a more suitable print result image with a simple configuration.

  According to the invention of claim 4, by determining whether the image data in the image file received from the image supply device is printed in color or monochrome based on the image data in the image file, There is an effect that a more preferable print result image can be obtained with a simple configuration.

  According to the invention of claim 5, the convenience can be improved by using the shooting condition information stored in the header of the image file of the commonly used Exif file format. Play.

  According to the sixth aspect of the present invention, even when image data shot in color is determined to be printed in monochrome, the image data shot in color is converted into a monochrome image. Thus, for example, for image data obtained by photographing a white board in color, monochrome output of one K color material is possible, so that the CMY color material can be saved and neat and less blurred and scattered. There is an effect that a suitable printing result image can be obtained. In addition, depending on the image forming apparatus, an effect of increasing the printing speed can be expected.

  According to the seventh aspect of the present invention, it is easy to determine whether the image file received from the image supply device has been shot in color or monochrome based on the shooting condition information embedded in the image file. With this arrangement, it is possible to obtain a more suitable print result image.

  According to the eighth aspect of the present invention, it is determined whether the image data in the image file received from the image supply device is to be printed in color or monochrome based on the shooting condition information embedded in the image file. As a result, it is possible to obtain a more suitable print result image with a simple configuration.

  According to the invention of claim 9, by determining whether the image data in the image file received from the image supply device is printed in color or monochrome based on the image data in the image file, There is an effect that a more preferable print result image can be obtained with a simple configuration.

  According to the invention of claim 10, the convenience can be improved by using the shooting condition information stored in the header of the image file of the commonly used Exif file format. Play.

  According to the eleventh aspect of the present invention, even when image data shot in color is determined to be printed in monochrome, the image data shot in color is converted into a monochrome image. Thus, for example, for image data obtained by photographing a white board in color, monochrome output of one K color material is possible, so that the CMY color material can be saved and neat and less blurred and scattered. There is an effect that a suitable printing result image can be obtained. In addition, depending on the image forming apparatus, an effect of increasing the printing speed can be expected.

  According to the twelfth aspect of the present invention, it is easy to determine whether the image file received from the image supply device is shot in color or monochrome based on the shooting condition information embedded in the image file. With this arrangement, it is possible to obtain a more suitable print result image.

  According to the invention of claim 13, it is determined whether to print the image data in the image file received from the image supply device in color or monochrome based on the shooting condition information embedded in the image file. As a result, it is possible to obtain a more suitable print result image with a simple configuration.

  According to the fourteenth aspect of the present invention, by determining whether the image data in the image file received from the image supply device is printed in color or monochrome based on the image data in the image file, There is an effect that a more preferable print result image can be obtained with a simple configuration.

  According to the fifteenth aspect of the present invention, even if image data shot in color is determined to be printed in monochrome, the image data shot in color is converted into a monochrome image. Thus, for example, for image data obtained by photographing a white board in color, monochrome output of one K color material is possible, so that the CMY color material can be saved and neat and less blurred and scattered. There is an effect that a suitable printing result image can be obtained. In addition, depending on the image forming apparatus, an effect of increasing the printing speed can be expected.

  According to the invention of claim 16, it is simplified by determining whether the image file received from the image supply device is shot in color or monochrome based on shooting condition information embedded in the image file. With this arrangement, it is possible to obtain a more suitable print result image.

  According to the seventeenth aspect of the present invention, it is determined whether to print the image data in the image file received from the image supply device in color or monochrome based on the shooting condition information embedded in the image file. As a result, it is possible to obtain a more suitable print result image with a simple configuration.

  According to the invention of claim 18, by determining whether the image data in the image file received from the image supply device is printed in color or monochrome based on the image data in the image file, There is an effect that a more preferable print result image can be obtained with a simple configuration.

  According to the nineteenth aspect of the present invention, it is possible to improve convenience by using the shooting condition information stored in the header of an image file in a commonly used Exif file format. Play.

  Exemplary embodiments of an image printing system according to the present invention will be explained below in detail with reference to the accompanying drawings.

(First embodiment)
[1. Description of image printing system configuration of the embodiment]
FIG. 1 is a schematic configuration diagram showing an image printing system according to a first embodiment of the present invention. As shown in FIG. 1, the image printing system of the present embodiment includes a color laser printer A as an image forming apparatus and a digital still camera as an image supply apparatus via a USB (Universal Serial Bus) cable C as an interface. B is connected.

[1-1. Explanation of Color Laser Printer A]
First, the color laser printer A which is an image forming apparatus will be described. FIG. 2 is a block diagram showing an example of the configuration of the color laser printer A. As shown in FIG. As shown in FIG. 2, the color laser printer A includes a system control unit 1 that performs various control processes such as a control process of each part of the color laser printer A and an image forming process. The system control unit 1 is mainly configured by a CPU (Central Processing Unit) constituting a microcomputer, and the entire color laser printer A according to a control processing program stored in the system memory 2 or the magnetic disk device 10. Responsible for control.

  The system control unit 1 includes a system memory 2, a parameter memory 3, a clock circuit 4, an operation display unit 5, a page memory 6, a printer engine 7, a transport system unit 8, an external device interface circuit 9, and a magnetic disk device 10. Are connected via the internal bus 11, and data exchange between these elements is mainly performed via the internal bus 11.

  The system memory 2 stores a control processing program executed by the system control unit 1 and various data necessary for executing the control processing program, and constitutes a work area of the system control unit 1. 3 is for storing various kinds of information unique to the color laser printer A.

  The clock circuit 4 outputs current time information. The operation display unit 5 is for operating the color laser printer A, and includes various operation keys and various display devices.

  The page memory 6 holds image data to be printed (print drawing image), and the printer engine 7 records and outputs an image of the image data held in the page memory 6 on a recording sheet (not shown). Is for. The paper feeding / conveying system unit 8 separates the recording paper from a paper cassette or the like (not shown) holding the recording paper, feeds the recording paper to the image recording position of the printer engine 7, and finally the paper discharge tray ( (Not shown). Since the color laser printer A of the present embodiment is a laser printer, the printer engine 7 forms an image by an electrophotographic process method and records it on a recording sheet.

  The external device interface circuit 9 is connected to the digital still camera B via the USB cable C to receive image data and the like, and print capability information (output quality, paper size, paper type, Support image format, date output, file name output, layout information for paper size, etc.).

  The magnetic disk device 10 is for storing various print document information and for storing other appropriate information files.

[1-2. Description of digital still camera B]
Next, the digital still camera B which is an image supply device will be described. FIG. 3 is a block diagram schematically showing the hardware configuration of the digital still camera B, and FIG. 4 is a schematic perspective view showing the external configuration thereof.

  As shown in FIG. 3, the digital still camera B, which is an image supply device, schematically includes a signal processing unit 12, a memory control unit 13, a main control unit 14, a frame memory 15, an interface 16, A display unit 17, an external storage unit 18 capable of recording / reading various data with respect to a medium 26 that is a storage medium for storing or distributing information outside or obtaining information from the outside, and a shooting mode setting unit 19 An imaging unit 20, a touch panel 27, an operation unit 28, and a microphone 29. The imaging unit 20 includes a lens 21, a diaphragm 22, a shutter 23, a photoelectric conversion element 24, and a preprocessing unit 25.

  Here, the signal processing unit 12 is connected to the preprocessing unit 25, the memory control unit 13, the main control unit 14, and the interface 16. The memory control unit 13 is connected to the frame memory 15. Further, the main control unit 14 is connected to the memory control unit 13, the shooting mode setting unit 19, and the microphone 29. The microphone 29 is connected to the main controller 14 via an analog-digital converter (A / D converter) 30. The frame memory 15 is connected to the memory control unit 13. The interface 16 is connected to the display unit 17, the external storage unit 18, the touch panel 27, and the operation unit 28. In addition, a USB cable C for communicating with the color laser printer A is also connected to the interface 16.

  On the other hand, in the imaging unit 20, the lens 21, the diaphragm 22, the shutter 23, and the photoelectric conversion element 24 are arranged in this order on the optical axis, and the photoelectric conversion element 24 is connected to the preprocessing unit 25. For example, a CCD (Charge Coupled Device) is used for the photoelectric conversion element 24 of the imaging unit 20. The preprocessing unit 25 includes an analog signal processing unit and an analog-digital converter (A / D converter) including a preamplifier and an automatic gain control circuit (Auto Gain Control-AGC). After the output analog video signal is subjected to preprocessing such as amplification and clamping, the analog video signal is converted into a digital video signal.

  The signal processing unit 12 includes a digital signal processor (DSP processor) and the like, has an image compression function, and performs various functions such as color separation, white balance adjustment, and γ correction on the digital video signal obtained in the imaging unit 20. The image processing is performed.

  The memory control unit 13 performs a process of storing the image signal processed in this way in the frame memory 15 or reading the image signal stored in the frame memory 15.

  The main control unit 14 includes a central processing unit (CPU) that centrally controls each unit of the digital still camera B, a read only memory (ROM) that stores various control programs used by the CPU, and a RAM that serves as a work area. (Random Access Memory). In place of the control program stored in the ROM, the medium 26 storing the control program is mounted on the external storage unit 18 of the digital still camera B as shown in FIG. A control program may be executed. The frame memory 15 stores at least two images, and a semiconductor memory such as a VRAM, SRAM, or DRAM is generally used.

  Here, the image signal read from the frame memory 15 is subjected to signal processing such as image compression in the signal processing unit 12 and then stored as an image file in the external storage unit 18 via the interface 16. The external storage unit 18 reads and writes various signals such as image signals supplied via the interface 16 and is constituted by an IC memory card, a magneto-optical disk, or the like.

  Conversely, reading of the image signal recorded in the external storage unit 18 is performed by transmitting the image signal to the signal processing unit 12 via the interface 16 and performing image expansion in the signal processing unit 12. On the other hand, the image signal read from the external storage unit 18 and the frame memory 15 is displayed after the signal processing unit 12 performs signal processing such as digital-analog conversion (D / A conversion) and amplification on the image signal. This is performed by transmitting to the display unit 17 via the interface 16. Here, the display unit 17 displays an image in accordance with an image signal supplied via the interface 16 and is configured by, for example, an LCD (Liquid Crystal Display) installed in a casing of the digital still camera B.

  In addition, as shown in FIG. 3, the digital still camera B has an appearance of a power switch 31, a shutter 32, a finder 33, a shooting mode setting key 34 for setting a shooting mode in the shooting mode setting unit 19, and a display. Scroll keys 35 and 36 for scrolling the image displayed on the unit 17 in the vertical direction, a determination key 37, and the like are provided. The shutter 32, the shooting mode setting key 34, the scroll keys 35 and 36, and the enter key 37 constitute the operation unit 28 described above.

  By the way, the image file stored in the external storage unit 18 is an Exif (Exchangeable Image File Format) file format. As shown in FIG. 5, the Exif file format is composed of an image data portion for recording a JPEG image (TIFF format if uncompressed) as captured image data and an Exif header portion. In the Exif header section, the digital still camera B manufacturer name, model name, digital still camera software version, exposure program mode, metering mode, aperture value, aperture value, shutter speed, focal length, focus distance, exposure compensation Shooting condition information c such as value, ISO sensitivity value, date and time, light source discrimination, and strobe use is stored. Such shooting condition information is generated and given by shooting condition information generation processing executed in the signal processing unit 12. In addition, in the Exif header section, in addition to the shooting condition information c, additional information (image information, thumbnail images, etc.) recorded in the TIFF format, WAV files that are audio data recorded at the time of shooting, and the like are recorded. Is possible.

  In addition, in the digital still camera B according to the present embodiment, text information that is a memo such as a title name for a captured image can be recorded as additional information in the Exif header portion of the Exif file. Such text information is displayed by, for example, displaying a predetermined character string on the display unit 17 by the CPU of the main control unit 14 according to the control program, and selecting the text information by operating the operation unit 28 of the user. The software keyboard is displayed on the screen 17, and characters are input by operating the operation unit 28 of the user via the software keyboard.

[2. Description of the operation of the image printing system of the present embodiment]
Next, the operation of the image printing system will be described.

[2-1. Explanation of direct print system]
The color laser printer A and the digital still camera B according to the present embodiment comply with a standard of a well-known direct print system that can directly print out an image file in the digital still camera by connecting the digital still camera and the printer device. Supported. That is, according to the color laser printer A and the digital still camera B of the present embodiment, the digital still camera B and the color laser printer A are connected via the USB cable C, and various print settings are made on the digital still camera B side. A print command and an error message from the color laser printer A can be displayed on the digital still camera B.

  FIG. 6 shows an example of a communication procedure when the digital still camera B instructs the color laser printer A to print an image.

  First, the user connects the digital still camera B and the color laser printer A with the USB cable C, and instructs the digital still camera B to print an image.

  As a result, the digital still camera B transmits a command “print service request” to the color laser printer A, and then transmits a command “capability request” to the color laser printer A.

  When the color laser printer A receives the command “capability request”, the color laser printer A transmits capability information that can be specified at the time of printing in its own terminal in the response “capability notification”.

  Here, the capability information includes output quality (high speed / normal / high image quality, etc.), paper size, acceptable image format, date output, number of aggregations, and the like. The “number of aggregations” indicates the number of frames (number of images) that can be specified when selecting an aggregation layout that is an arrangement layout in which a plurality of images are arranged on one sheet.

  As a result, the digital still camera B allows the user to input printing conditions (output quality, paper size, date output presence / absence, aggregation number, index printing instruction, etc.) in accordance with the capability information notified from the color laser printer A. The user selects the image to be printed.

  When the user operation is completed, the digital still camera B transmits a command “job start instruction” including print job information as shown in FIG. 7 to the color laser printer A. At this time, when “index printing” is instructed by a user operation, “index printing” is arranged as a print command. The print job information includes a paper size designated by the user, the number of images designated by the user for index printing (number of print images (k)), and a user designated for index printing. K print image data IDs for identifying the image are included. If all images are automatically selected during index printing, the number of print images (k) is set to the number of all images stored in the digital still camera B at that time. As the image data ID, all representing all the images are set.

  Next, the color laser printer A sequentially designates one or more print image data IDs included in the received print job information, and transmits one or more responses “file acquisition request” to the digital still camera B.

  Thereby, the digital still camera B transmits the image data of the designated print image data ID to the color laser printer A one by one.

  The color laser printer A forms index print data based on the received image data, and performs a printing operation as needed. Here, since the received image data is encoded in any one of the image formats, it is decoded to create, for example, RGB format image data, and the RGB format image data is converted to print data. . At this time, the image to be printed is appropriately scaled according to the relationship between the size of the image data (resolution and the number of pixels) and the size of the paper or print area to be printed.

  When all printing operations are completed, the result is sent to the digital still camera B as a response “processing result notification”.

  When the digital still camera B receives the response “processing result notification” from the color laser printer A, the digital still camera B ends the print job.

[2-2. Explanation of characteristic functions of color laser printer A]
Next, characteristic functions that are exhibited when the system control unit 21 of the color laser printer A operates according to the control processing program will be described.

  FIG. 8 is a functional block diagram relating to characteristic functions that are exhibited when the system control unit 21 provided in the color laser printer A operates according to the control processing program. As shown in FIG. 8, the system control unit 21 operates in accordance with the control processing program, thereby performing communication means 41, image data color determination means 42, print mode determination means 43, color image color conversion means 44, color image gray conversion. Each function of the means 45 and the image rendering means 46 is exhibited.

  The communication unit 41 exhibits a function of controlling communication with the digital still camera B connected via the USB cable C, receives image data from the digital still camera B, and receives digital data from the digital still camera B. And print capability information (output quality, paper size, paper type, supported image format, date output, file name output, layout information for paper size, etc.).

  The image data color determination unit 42 has a function of determining an image mode based on information (imaging condition information: image mode) embedded in an image file received from the digital still camera B by the communication unit 41. The image data color determination means 42 sends the image file to the print mode determination means 43 when the image mode is the color mode, and sends the image file to the image rendering means 46 when the image mode is the monochrome mode.

  The print mode determination unit 43 exhibits a function of determining the print mode based on information (imaging condition information: print mode) embedded in the image file received from the digital still camera B by the communication unit 41. The print mode determination unit 43 sends the image file to the color image color conversion unit 44 when the print mode is the color mode, and sends the image file to the color image gray conversion unit 45 when the print mode is the monochrome mode.

  The color image color conversion means 44 converts from RGB to CMYK using BG / UCR, for example. The color-converted image is sent to the image rendering means 46.

  The color image gray conversion unit 45 converts the luminance from RGB to gray, for example. The color-converted image is sent to the image rendering means 46. That is, the color image gray conversion unit 45 is an image conversion unit that converts image data in an image file photographed in color into a monochrome image.

  The image rendering means 46 renders the monochrome image sent from the image data color determination means 42 or the color image gray conversion means 45 in the page memory 6 using only the K version. The image rendering means 46 renders the color image sent from the color image color converting means 44 in the page memory 6 using the CMYK version. When drawing for one page of paper is completed, the drawing in the page memory 6 is transferred to the printer engine 7 and printed.

  FIG. 9 shows an example in which four images (first color, second monochrome, third monochrome, fourth color) are printed on each sheet of paper. The first sheet is a color image photographed in the color mode, and since the color mode is designated as the print mode, CMYK printing is performed. Since the second image is a monochrome image taken in monochrome mode, it is output in K1 color. The third image is a color image taken in the color mode, but the monochrome mode is designated as the print mode. Therefore, the luminance is converted by the color image gray conversion means 45 to be converted into a monochrome image and output in K1 color. The The fourth sheet is a color image photographed in the color mode, and since the color mode is designated as the print mode, CMYK printing is performed.

  Here, a drawing method using the K1 color will be described with reference to FIG. For easy understanding, it is assumed that all CMYK planes have a background color (halftone). The figure to be drawn is a black ellipse. In BG / UCR, which is a commonly used conversion from RGB to CMYK, 100% of black is K = 100%, C = M = Y = 50%, etc. Often expresses black. This is effective when considering the continuity with other colors when there are chromatic colors, but a large amount of color material is used, resulting in a slightly thick print result. If all the figures to be drawn are known to be achromatic (gray) from the beginning, the drawing method using only K for the color material and not the CMY color material can save CMY color material, A clean print result with little scattering is obtained. In addition, the effect of increasing the printing speed can be expected depending on the printing apparatus. In the ellipse of the drawing figure of FIG. 10, K = 100% and C = M = Y = 0%. The drawing result is K = 100% in the K version ellipse and 0% in the CMY version ellipse. The background remains outside the ellipse.

  FIG. 11 shows an example in which four images are printed on one sheet. Image 1 and image 4 are color images and are printed in CMYK as before because color is designated in the print mode. Since image 2 is a monochrome image taken in monochrome mode, it is printed in K1 color. Since the image 3 is a color image taken in the color mode, but the monochrome mode is designated as the print mode, the luminance is converted by the color image gray conversion unit 45 to be converted into a monochrome image and printed in K1 color. .

  As described above, according to the present embodiment, even if the image data is captured in color, if it is determined to print in monochrome, the image data captured in color is converted into a monochrome image. Thus, for example, for image data obtained by photographing a white board in color, monochrome output of one K color material is possible, so that the CMY color material can be saved and neat and less blurred and scattered. There is an effect that a suitable printing result image can be obtained. In addition, depending on the image forming apparatus, an effect of increasing the printing speed can be expected.

  Further, by determining whether to print the image data in the image file received from the image supply device based on the shooting condition information embedded in the image file in color or monochrome, a simple configuration is more suitable. A print result image can be obtained.

  The control processing program executed in the system control unit 1 of the color laser printer A that is the image forming apparatus of the present embodiment is provided by being stored in advance in the system memory 2, the magnetic disk device 10, or the like. However, it is not limited to this. For example, the control processing program may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. The control processing program may be provided or distributed via a network such as the Internet. Further, the control processing program is provided as a file in an installable or executable format and recorded on a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, or a DVD. It may be configured.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIG. The same parts as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is also omitted. In the first embodiment, the print mode determination unit 43 determines the print mode of the image file received from the digital still camera B by the communication unit 41, and switches the color processing of the image. The present embodiment is different in that the print mode of the image file is determined according to the image data in the image file received from the digital still camera B.

  FIG. 12 is a functional block diagram relating to characteristic functions that are exhibited when the system control unit 21 provided in the color laser printer A operates according to a control processing program. As shown in FIG. 12, the system control unit 21 operates in accordance with the control processing program, thereby performing communication means 41, image data color determination means 42, print mode determination means 53, color image color conversion means 44, color image gray conversion. Each function of the means 45 and the image rendering means 46 is exhibited.

The print mode determination unit 53 according to the present embodiment has a function of determining image data in an image file received from the digital still camera B by the communication unit 41 and switching the color processing of the image. Here, a monochrome image determination method in the print mode determination unit 53 will be described. As a method for determining a monochrome image, all pixels of the target image are examined, and if all pixels are R = G = B, it is determined that the image is a monochrome image. In addition, R≈G≈B, which is a color that includes minute chromatic colors that cannot be determined by human eyes, is also determined as a gray pixel. For example, if the color difference between two arbitrary colors in RGB and the threshold value T are given,
| RG | ≦ Trg, | GB | ≦ Tgb, | BR | ≦ Tbr
Are determined to be chromatic colors. Of course, Trg = Tgb = Tbr may be set for simplicity. The same applies when RGB is normalized to an integer value of 0-255.

  As described above, according to the present embodiment, even if the image data is captured in color, if it is determined to print in monochrome, the image data captured in color is converted into a monochrome image. Thus, for example, for image data obtained by photographing a white board in color, monochrome output of one K color material is possible, so that the CMY color material can be saved and neat and less blurred and scattered. There is an effect that a suitable printing result image can be obtained. In addition, depending on the image forming apparatus, an effect of increasing the printing speed can be expected.

  Further, by determining whether the image data in the image file received from the image supply device is to be printed in color or monochrome based on the image data in the image file, a more suitable print result image with a simple configuration Can be obtained.

  In each embodiment, the color laser printer A is applied as the image forming apparatus. However, the present invention is not limited to this, and an ink jet printer may be applied to the image forming apparatus. When the ink jet printer is applied to the image forming apparatus as described above, it is natural that the printer engine 7 of the image forming apparatus prints out data on a recording medium using a known ink jet printing technique. Is.

  In each embodiment, the digital still camera B is applied as the image supply device. However, the present invention is not limited to this, and a storage that can hold a large amount of image data may be used.

1 is a schematic configuration diagram illustrating an image printing system according to a first embodiment of the present invention. It is a block diagram which shows an example of a structure of a color laser printer. It is a block diagram which shows roughly the hardware constitutions of a digital still camera. It is a schematic perspective view which shows the external appearance structure of a digital still camera. It is explanatory drawing which shows an Exif file format. It is a sequence diagram which shows an example of the communication procedure at the time of a digital still camera commanding image printing with respect to a color laser printer. FIG. 6 is a schematic diagram illustrating print job information. It is a functional block diagram concerning the characteristic function exhibited when the system control part with which a color laser printer is equipped operates according to a control processing program. FIG. 6 is a plan view illustrating an example in which four images are printed on each sheet of paper. It is explanatory drawing which shows the drawing method in K1 color. FIG. 6 is a plan view illustrating an example of printing four images on one sheet. It is a functional block diagram concerning the characteristic function exhibited when the system control part with which the color laser printer concerning a 2nd embodiment of the present invention is operated according to a control processing program.

Explanation of symbols

42 Image data color determination means 43, 53 Print mode determination means 45 Image conversion means A Image forming apparatus B Image supply apparatus C Interface

Claims (19)

In an image forming apparatus that receives an image file transferred from an image supply apparatus connected via an interface and prints image data in the image file.
Image data color determination means for determining whether the image file received from the image supply device is captured in color or monochrome;
Print mode determining means for determining whether image data in an image file determined to be photographed in color by the image data color determining means is printed in color or monochrome; and
Image conversion means for converting image data in an image file photographed in color determined to be printed in monochrome by the print mode determination means into a monochrome image;
An image forming apparatus comprising: The image data color determining means determines whether the image file received from the image supply device is shot in color or monochrome based on shooting condition information embedded in the image file;
The image forming apparatus according to claim 1. The print mode determination means determines whether to print the image data in the image file received from the image supply device in color or monochrome based on the shooting condition information embedded in the image file;
The image forming apparatus according to claim 1. The print mode determination means determines whether to print the image data in the image file received from the image supply device in color or monochrome based on the image data in the image file;
The image forming apparatus according to claim 1. The image file is an Exif (Exchangeable Image File Format) file format,
The shooting condition information is stored in a header of the image file.
The image forming apparatus according to claim 2, wherein the image forming apparatus is an image forming apparatus. In an image printing system in which an image supply apparatus capable of supplying an image file and an image forming apparatus that prints image data in the image file transferred from the image supply apparatus are connected via an interface.
Image data color determination means for determining whether the image file received from the image supply device is captured in color or monochrome;
Print mode determining means for determining whether image data in an image file determined to be photographed in color by the image data color determining means is printed in color or monochrome; and
Image conversion means for converting image data in an image file photographed in color determined to be printed in monochrome by the print mode determination means into a monochrome image;
An image printing system comprising: The image data color determining means determines whether the image file received from the image supply device is shot in color or monochrome based on shooting condition information embedded in the image file;
The image printing system according to claim 6. The print mode determination means determines whether to print the image data in the image file received from the image supply device in color or monochrome based on the shooting condition information embedded in the image file;
The image printing system according to claim 6. The print mode determination means determines whether to print the image data in the image file received from the image supply device in color or monochrome based on the image data in the image file;
The image printing system according to claim 6. The image file is an Exif (Exchangeable Image File Format) file format,
The shooting condition information is stored in a header of the image file.
The image printing system according to claim 7 or 8, wherein An image data color determination function for determining whether the image file received from the image supply device connected via the interface is captured in color or monochrome;
A print mode determination function for determining whether the image data in the image file determined to have been shot in color by the image data color determination function is to be printed in color or monochrome;
An image conversion function for converting image data in an image file shot in color determined to be printed in monochrome by the print mode determination function into a monochrome image;
A program that causes a computer to execute. The image data color determination function determines whether the image file received from the image supply device is shot in color or monochrome based on shooting condition information embedded in the image file.
12. The program according to claim 11, wherein: The print mode determination function determines whether to print image data in the image file received from the image supply device in color or monochrome based on shooting condition information embedded in the image file.
12. The program according to claim 11, wherein: The print mode determination function determines whether the image data in the image file received from the image supply device is printed in color or monochrome based on the image data in the image file;
12. The program according to claim 11, wherein: An image data color determination step for determining whether the image file received from the image supply device connected via the interface is captured in color or monochrome;
A print mode determination step for determining whether the image data in the image file determined to have been photographed in color by the image data color determination step is to be printed in color or monochrome;
An image conversion step of converting image data in an image file photographed in a color determined to be printed in monochrome by the print mode determination step into a monochrome image;
An image printing method comprising: The image data color determination step determines whether the image file received from the image supply device is shot in color or monochrome based on shooting condition information embedded in the image file.
The image printing method according to claim 15. The print mode determination step determines whether to print the image data in the image file received from the image supply device in color or monochrome based on the shooting condition information embedded in the image file.
The image printing method according to claim 15. The print mode determination step determines whether to print the image data in the image file received from the image supply device based on the image data in the image file in color or monochrome.
The image printing method according to claim 15. The image file is an Exif (Exchangeable Image File Format) file format,
The shooting condition information is stored in a header of the image file.
18. The image printing method according to claim 16 or 17, wherein:

Images