JP4210254B2 - Printer and printing method - Google Patents

Description

  The present invention relates to a printer and a printing method for reading an image file including a main image taken by a digital camera, a thumbnail image generated from the main image, and shooting information including shooting date and time, and printing the main image. It is about.

Printers that read an image taken by a digital camera and print out the read image are widely used. Some printers automatically synthesize a shooting date and time in an image file with an image and print out an image with the shooting date and time stamped (see, for example, Patent Document 1).
JP 2002-27229 A

  By the way, some digital cameras record a shooting date and time by combining the shooting date and time in advance. When an image photographed by such a digital camera is printed out by the printer described in Patent Document 1, there is a problem that the photographing date / time is described twice.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a printer that can prevent the double description of date and time.

  Since the shooting date / time is not combined with the thumbnail image, it is possible to determine whether the shooting date / time is combined with the main image by comparing the main image with the thumbnail image.

  Based on the above principle, the printer of the present invention reduces the main image to the same size as the thumbnail image and generates a reduced image, and calculates the difference between the pixel data of the reduced image and the thumbnail image. Computation means, and a judgment means for comparing the calculation result of the difference and a preset threshold value to determine whether or not the shooting date and time have been combined with the main image, and combining the shooting date and time with the main image If it is determined that the image has been processed, the print date is output without combining the shooting date with the main image, and if it is determined that the shooting date has not been combined with the main image, the shooting date is It is characterized by combining and outputting a print.

  It is preferable to provide a setting changing means for changing the setting of the threshold.

  The image processing unit performs the reduction using a plurality of algorithms to generate a plurality of reduced images, and the determination unit is the most out of the calculation results of the differences between the plurality of reduced images and the thumbnail images. It is preferable to perform the determination based on a small difference.

  The difference calculation means repeatedly performs the difference calculation by shifting pixel positions of the reduced image and the thumbnail image, and the determination means determines the smallest difference among the calculation results of the difference performed a plurality of times. It is preferable to make the determination based on this.

  The image processing unit rotates the reduced image to generate a plurality of reduced images, and the determination unit determines the smallest difference among the calculation results of the differences between the plurality of reduced images and the thumbnail image. It is preferable to make the determination based on this.

  Preferably, the difference calculation means calculates only a difference between pixel data at four corners of the reduced image and the thumbnail image.

  When it is determined that the shooting date / time has been combined with the main image, a part of the main image having a large difference is extracted from the difference calculation result, and a character is subjected to character recognition processing on the extracted part. It is preferable to provide a recognition means.

  The image processing means detects the complexity of the main image, and when combining the photographing date and time with the main image, the image processing means may perform on the low complexity portion based on the detection result of the complexity. preferable.

  Further, the printing method of the present invention reduces the main image to the same size as the thumbnail image, generates a reduced image, calculates the difference between the reduced image and the pixel data of the thumbnail image, and calculates the difference calculation result. Compared with a preset threshold value, it is determined whether or not the shooting date / time is combined with the main image. If it is determined that the shooting date / time is combined with the main image, the main image is shot. A printout is performed without combining the date and time, and when it is determined that the shooting date and time have not been combined with the main image, the shooting date and time are combined with the main image and the printout is output.

  The reduction is performed using a plurality of algorithms to generate a plurality of reduced images, and the determination is performed based on the smallest difference among the calculation results of the differences between the plurality of reduced images and the thumbnail images. It is preferable.

  Preferably, the difference calculation is repeated by shifting the pixel positions of the reduced image and the thumbnail image, and the determination is performed based on a difference calculation result that has been performed a plurality of times and having the smallest difference.

  Preferably, the reduced image is rotated to generate a plurality of reduced images, and the determination is performed based on the smallest difference among the calculation results of the differences between the plurality of reduced images and the thumbnail images.

  It is preferable to calculate only a difference between pixel data at four corners of the reduced image and the thumbnail image.

  When it is determined that the shooting date and time have been combined with the main image, a portion of the main image having a large difference is extracted from the difference calculation result, and character recognition processing is performed on the extracted portion. Is preferred.

  When detecting the complexity of the main image and compositing the shooting date and time on the main image, it is preferable to perform the processing on the low complexity portion based on the detection result of the complexity.

  The printer according to the present invention compares the main image with the thumbnail image to determine whether or not the shooting date / time is preliminarily combined with the main image. Since the shooting date / time is not combined, it is possible to prevent double date / time writing.

  In FIG. 1, a printer 10 to which the present invention is applied includes a main body 12, a monitor 14, a keyboard 16, and a mouse 18 connected to the main body 12, and a digital camera 20 can be connected via a USB cable or the like. It has become. The printer 10 reads the image file 40 (see FIG. 2) from the digital camera 20 and prints out the image in the image file 40 onto the recording paper 21.

  As shown in FIG. 2, the digital camera 20 creates an image file 40 for each shooting, and in this image file 40, a main image 42 obtained by shooting, and tag information (Exif tag) related to the main image 42. 44 is stored. As the tag information 44, a thumbnail image 46 and shooting information are stored. The shooting information includes setting information of the digital camera 20 such as white balance setting, presence / absence of flash emission, and shooting date / time information 48.

  The printer 10 is, for example, an ink jet printer, a thermal printer, a laser printer, or the like. The main body unit 12 is provided with a printing unit 50 that prints a full color image on the recording paper 21. The main body 12 is provided with a CPU 52, and the overall operation of the printer 10 is comprehensively controlled by the CPU 52.

  In addition to the printing unit 50 described above, a RAM 54, a ROM 56, and an input / output I / F 58 are connected to the CPU 52 via a bus 60. The RAM 54 stores the image file 40 transmitted from the digital camera 20. In the ROM 56, in addition to a program for starting and controlling the printer 10, a reduction algorithm, a threshold value, and the like used for determination described later are stored.

  The input / output I / F 58 is connected to the USB connector 59, the monitor 14, the keyboard 16, and the mouse 18. The USB connector 59 mediates reception of image data from the digital camera 20. The monitor 14 displays the main image 42 and the thumbnail image 46 and also displays a print instruction screen for instructing the number of prints of the main image 42 and execution of the print. The keyboard 16 and the mouse 18 are operated when inputting an instruction on the print instruction screen.

  The CPU 52 performs printing on the recording paper 21 by driving and controlling the printing unit 50 in accordance with a print instruction input from the keyboard 16 and the mouse 18. The CPU 52 reads the main image 42 and the shooting date / time information 48 from the image file 40 stored in the RAM 54, and performs a combining process for combining the read shooting date / time information 48 with, for example, the lower right of the main image 42. Then, the synthesized image is printed on a recording sheet. As a result, the shooting date and time is described in the printed image.

  However, as described above, there are digital cameras that pre-combine the captured date and time with the captured image and record the combined image as the main image. When the composition process is performed, the shooting date and time are described twice in the printed image. For this reason, the printer 10 is provided with a determination unit 70 that determines whether or not the shooting date and time are combined in advance with the main image. If it is determined that the shooting date / time is combined with the main image in advance, the main image is printed as it is without performing the shooting date / time combining process described above.

  The determination unit 70 includes an image processing circuit 71, a difference calculation circuit 72, and a determination circuit 73, and compares the main image 42 with a thumbnail image 46 that is not subjected to shooting date / time composition processing, thereby making the determination. Do. Hereinafter, determination will be described based on the conceptual diagram shown in FIG. 3A shows a case where the shooting date / time is not combined with the main image 42, and FIG. 3B shows a case where the shooting date / time is combined with the main image 42. FIG.

  In the determination, first, the image processing circuit 71 generates a comparison image 74 in which the main image 42 is reduced to the same size as the thumbnail image 46. The image processing circuit 71 generates a comparison image 74 by reducing the main image 42 based on the reduction algorithm stored in the ROM 56, and transmits the comparison image 74 to the difference calculation circuit 72.

  The difference calculation circuit 72 takes a pixel-by-pixel difference between the comparison image 74 and the thumbnail image 46 and generates difference data 76 from which noise has been removed. The difference data 76 generated in this way includes the number of pixels in which the difference has occurred between the comparison image 74 and the thumbnail image 46, the position of the pixel in which the difference has occurred, the magnitude of the difference that has occurred, and the like. Is included.

  The determination circuit 73 compares the difference data 76 with the threshold value stored in the ROM 56 to determine whether or not the shooting date / time is combined with the main image 42. As the threshold value, for example, a plurality of threshold values such as a threshold value related to the number of pixels in which a difference has occurred, a threshold value related to the position of the pixel in which the difference has occurred, and a threshold value related to the magnitude of the generated difference are set.

  Then, as shown in FIG. 3A, the determination circuit 73 has a threshold value range in which the number of pixels in which the difference has occurred is smaller than the set threshold value and the position of the pixel in which the difference has occurred is set. If the image is scattered over the entire screen, it is determined that the shooting date / time is not combined with the main image 42. On the other hand, as shown in FIG. 3B, the screen in which the number of pixels in which the difference has occurred is larger than the set threshold value and the position of the pixel in which the difference has occurred is within the set threshold value range. When the image data is concentrated on the four corners, it is determined that the shooting date / time is combined with the main image 42.

  Hereinafter, the operation of the present invention having the above configuration will be described with reference to the flowchart shown in FIG. First, the printer 10 and the digital camera 20 are connected via a USB cable or the like, and the image file 40 recorded on the digital camera 20 is taken into the RAM 54 of the printer 10. After the image file 40 is captured, the main image 42 stored in the image file 40 can be printed on a recording sheet by operating the keyboard 16 or the mouse 18 to input a print instruction.

  At the time of printing, the printer 10 determines whether or not the shooting date and time are combined with the main image 42 in advance. As shown in FIG. 5, the printer 10 generates a comparison image 74 in which the main image 42 is reduced to the same size as the thumbnail image 46. Next, the difference data 76 from which noise is removed by taking the difference between the comparison image 74 and the thumbnail image 46 is generated. Then, by comparing the difference data 76 with a threshold value stored in the ROM 56, it is determined whether or not the shooting date / time is combined with the main image 42 in advance.

  As a result of the determination, if it is determined that the shooting date / time has not been combined with the main image 42 in advance, the printer 10 reads the shooting date / time information 48 from the image file 40 and combines the shooting date / time information 48 with the main image 42. This combined image is printed on a recording sheet. On the other hand, if it is determined that the shooting date and time have been combined with the main image 42 in advance, the printer 10 prints the main image 42 as it is without performing the combining process.

  As described above, when the shooting date / time is not combined with the main image 42 in advance, the printer 10 performs the shooting date / time combining process on the main image 42, so that the image with the shooting date / time can be printed. . On the other hand, when the shooting date and time are preliminarily combined with the main image 42, the main image 42 is output as it is without being combined. For this reason, the shooting date and time are not described twice in the printed image.

  In the above-described embodiment, an example in which a threshold value used as a reference for determination is set in advance has been described. However, a user of a printer may set the threshold value. In this case, a threshold value setting unit is provided that reads a threshold value from the ROM and changes the read threshold value in accordance with an input operation from a keyboard or a mouse. Then, the printer may make a determination based on the changed threshold value. This is convenient because the determination accuracy can be freely adjusted.

  In the above embodiment, an example using one type of reduction algorithm has been described, but the present invention is not limited to this. For example, if the reduction algorithm used when the printer generates the comparison image is different from the reduction algorithm used when the digital camera generates the thumbnail image, regardless of whether the shooting date and time are combined or not There is a problem that the difference between the thumbnail image and the comparison image becomes large, and it is not possible to make a highly accurate determination. In order to prevent such a problem, a plurality of types of reduction algorithms may be used.

  In this case, the ROM 56 stores a plurality of types of reduction algorithms. 6 and 7, in the determination, the image processing circuit 71 reduces the main image 42 using a plurality of types of reduction algorithms to generate a plurality of comparison images 94a to 94d. The difference calculation circuit 72 takes the difference between each of the plurality of comparison images 94a to 94d and the thumbnail image 46 to generate difference data 96a to 96d. Of these difference data 96a to 96d, the determination circuit 73 generates difference data generated from the comparative image with the smallest difference and the thumbnail image, that is, difference data with the smallest sum of differences for each pixel included in the difference data. The determination is made by comparing (minimum difference data) with a threshold value.

  In this way, it is possible to prevent a decrease in determination accuracy due to a difference between the reduction algorithm used when the printer side generates the comparison image and the reduction algorithm used when the digital camera side generates the thumbnail image. In FIG. 6 and subsequent drawings, members similar to those in the above-described embodiment are described with the same reference numerals.

  In addition, for example, if the reference position such as the center of the image is different between the thumbnail image and the comparison image, the difference between the thumbnail image and the comparison image becomes large, and a highly accurate determination is made. There is a problem that it cannot be done. In order to prevent such a problem, a plurality of difference data may be generated while shifting the position of the comparison image.

  In this case, as shown in FIGS. 8 and 9, the difference calculation circuit 72 takes a difference from the thumbnail image 46 for each of the reduced images 124 a to 124 d in which the reference position of the comparison image 74 is shifted to obtain a plurality of difference data. 126a to 126d are generated. 6 and 7, the determination circuit 73 performs determination by comparing the minimum difference data among the difference data 126a to 126d with a threshold value. In this example, it is possible to prevent a decrease in determination accuracy due to a positional shift between the thumbnail image and the comparison image.

  Furthermore, if the image orientation is different between the thumbnail image and the comparison image, the difference between the thumbnail image and the comparison image becomes large, and there is a problem that a highly accurate determination cannot be performed. . In order to prevent such a problem, a plurality of difference data may be generated while rotating the comparison image.

  In this case, as illustrated in FIGS. 10 and 11, the image processing circuit 71 generates the comparison image 74 and then generates reduced images 154 a to 154 d in which the direction of the comparison image 74 is rotated. The difference calculation circuit 72 generates difference data 156a to 156d from each of the plurality of reduced images 154a to 154d and the thumbnail image 46. The determination circuit 73 performs determination by comparing the minimum difference data among the difference data 156a to 156d with a threshold value. In this example, it is possible to prevent a decrease in determination accuracy due to a difference in orientation between the thumbnail image and the comparison image.

  In the above-described embodiment, an example has been described in which it is determined whether or not the shooting date / time is combined with the main image by comparing the entire thumbnail image with the comparison image. However, the present invention is not limited to this. In many cases, the position where the shooting date and time are combined is the four corners of the image. Therefore, for example, only partial areas of the four corners of the thumbnail image and the four corners of the comparison image may be determined.

  In this case, as shown in FIGS. 12 and 13, the difference calculation circuit 72 extracts the four corner portions of the comparison image 74 generated by the image processing circuit 71 and the four corner portions of the thumbnail image 46, respectively. Differences are taken for each area, and difference data for four areas is generated. Then, the determination circuit 73 performs determination based on the difference data. Thus, the determination time can be shortened by limiting the area to be determined.

  In the above-described embodiment, the example in which it is determined whether or not the shooting date / time is combined based only on the comparison result between the difference data and the threshold value has been described, but the present invention is not limited to this. For example, a part of the main image that can be considered that the shooting date and time are combined, that is, a part of the main image having a large difference between the comparison image and the thumbnail image may be recognized, and the recognition result may be involved in the determination.

  In this case, a character recognition unit 210 is provided in the printer 10 as shown in FIG. The character recognizing unit 210 recognizes character information included in the image by analyzing the image and checking whether the character information matches preset character information. As shown in FIG. 15, the printer 10 first makes a determination by the same method as in the above embodiment. If it is determined that the shooting date and time are combined, the character recognition unit 210 extracts a main image portion having a large difference between the comparison image 74 and the thumbnail image 46, and is included in this portion. Recognize character information. As a result of character recognition, when a character string indicating the shooting date / time is detected, it is determined that the shooting date / time has been synthesized. Then, the main image 42 is printed as it is without performing the photographing date / time composition processing. If the character string indicating the shooting date / time is not detected as a result of character recognition, it is determined again that the shooting date / time has not been combined, and the shooting date / time combining process is performed. By doing so, the accuracy of determination can be further increased.

  In the above embodiment, when it is determined that the shooting date / time is not combined with the main image, the shooting date / time is combined with the lower right of the main image. Can be set to Also, for example, if the main subject overlaps the position where the shooting date and time are combined, the printed image will be difficult to see. For this reason, according to the image to print, the synthetic | combination position of imaging | photography date may be determined for every printing.

  In this case, as shown in FIG. 16, in the image composition processing, the image processing circuit 71 analyzes the main image 42 and examines the contrast component to detect the complexity of the main image 42 in the screen. For example, the contrast of an image is low in a monotonous image such as a flat wall, and is high in a complex image such as a leaf of a tree. The image processing circuit 71 detects that an image with a higher contrast is more complicated. Then, the printer 10 synthesizes the shooting date and time in an area with a low complexity of the main image 42. For example, for the main image 42 shown in FIG. 17A, as shown in FIG. 17B, the shooting date and time are combined in the upper right of the screen with low contrast.

  In this example, the composite position of the shooting date / time is determined based on the contrast component of the main image. However, the composite position of the shooting date / time may be determined based on the contrast component of the comparison image generated at the time of determination. Good. In addition to the contrast component of the image, it is possible to check the position of the main subject, the background, and the position of the building by performing image analysis. Alternatively, the synthesis position may be determined.

2 is a configuration diagram of a printer. FIG. It is explanatory drawing showing the mode in an image file. It is explanatory drawing which represents a mode that difference data are produced | generated. It is a flowchart showing a printing procedure. It is a flowchart showing a determination procedure. It is explanatory drawing which represents a mode that difference data are produced | generated. It is a flowchart showing a determination procedure. It is explanatory drawing which represents a mode that difference data are produced | generated. It is a flowchart showing a determination procedure. It is explanatory drawing which represents a mode that difference data are produced | generated. It is a flowchart showing a determination procedure. It is explanatory drawing which represents a mode that difference data are produced | generated. It is a flowchart showing a determination procedure. 2 is a configuration diagram of a printer. FIG. It is a flowchart showing a printing procedure. It is a flowchart showing a synthetic | combination procedure. It is explanatory drawing which represents a mode that a photography date is synthesize | combined notionally.

Explanation of symbols

10 Printer 20 Digital Camera 40 Image File 42 Main Image 44 Tag Information 46 Thumbnail Image 48 Shooting Date / Time Information 52 CPU
70 determination unit 71 image processing circuit 72 difference calculation circuit 73 determination circuit 74, 94a to 94d comparative image 76, 96a to 96d, 126a to 126d, 156a to 156d difference data 124a to 124d, 154a to 154d reduced image 210 character recognition unit

Claims (15)

In a printer that reads a main image shot by a digital camera, a thumbnail image generated from the main image, and shooting information including shooting date and time and prints out the main image,
Image processing means for reducing the main image to a size equal to the thumbnail image and generating a reduced image;
A computing means for computing a difference between pixel data of the reduced image and the thumbnail image;
A determination unit that compares the calculation result of the difference with a preset threshold value and determines whether or not the shooting date / time is combined with the main image;
If it is determined that the shooting date / time is combined with the main image, the shooting date / time is printed on the main image without being combined,
When it is determined that the shooting date / time has not been combined with the main image, the shooting date / time is combined with the main image to output a print.   2. The printer according to claim 1, further comprising setting changing means for changing the setting of the threshold value. The image processing means performs the reduction using a plurality of algorithms to generate a plurality of reduced images,
The printer according to claim 1, wherein the determination unit performs the determination based on a calculation result of the difference between the plurality of reduced images and the thumbnail image having the smallest difference. The difference calculation means repeatedly performs the difference calculation by shifting pixel positions of the reduced image and the thumbnail image,
The printer according to any one of claims 1 to 3, wherein the determination unit performs the determination based on a difference calculation result performed a plurality of times based on a difference having a smallest difference. The image processing means rotates the reduced image to generate a plurality of reduced images;
5. The determination unit according to claim 1, wherein the determination unit performs the determination based on an operation result of the difference between the plurality of reduced images and the thumbnail image having the smallest difference. Printer.   The printer according to claim 1, wherein the difference calculation unit calculates only a difference between pixel data at four corners of the reduced image and the thumbnail image.   When it is determined that the shooting date / time has been combined with the main image, a part of the main image having a large difference is extracted from the difference calculation result, and a character is subjected to character recognition processing on the extracted part. The printer according to claim 1, further comprising a recognition unit. The image processing means detects the complexity of the main image;
The printer according to any one of claims 1 to 7, wherein when the photographing date and time are combined with the main image, the processing is performed on the low complexity portion based on the detection result of the complexity. In a printing method for reading a main image shot by a digital camera, a thumbnail image generated from the main image, and an image file including shooting information including shooting date and time, and printing the main image,
Reducing the main image to a size equal to the thumbnail image to generate a reduced image;
Calculate the difference between the reduced image and the thumbnail image pixel data,
Compare the calculation result of the difference with a preset threshold value to determine whether or not the shooting date and time have been combined with the main image,
If it is determined that the shooting date / time is combined with the main image, the shooting date / time is printed on the main image without being combined,
When it is determined that the shooting date and time have not been combined with the main image, the shooting date and time are combined with the main image and printed. Performing the reduction using a plurality of algorithms to generate a plurality of reduced images;
The printing method according to claim 9, wherein the determination is performed based on an operation result of the difference between the plurality of reduced images and the thumbnail image having the smallest difference. Shifting the pixel positions of the reduced image and the thumbnail image and repeatedly calculating the difference,
The printing method according to claim 9 or 10, wherein the determination is performed based on a result of a difference performed a plurality of times based on a difference having a smallest difference. Rotating the reduced image to generate a plurality of reduced images;
The printing method according to claim 9, wherein the determination is performed based on an operation result of the difference between the plurality of reduced images and the thumbnail image having the smallest difference.   13. The printing method according to claim 9, wherein only a difference between pixel data at four corners of the reduced image and the thumbnail image is calculated.   When it is determined that the shooting date and time have been combined with the main image, a portion of the main image having a large difference is extracted from the difference calculation result, and character recognition processing is performed on the extracted portion. The printing method according to any one of claims 9 to 13. Detecting the complexity of the main image;
The printing method according to claim 9, wherein when the photographing date and time are combined with the main image, the processing is performed on the low complexity portion based on the detection result of the complexity. .

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