JP4121807B2 - Image reading apparatus and image reading method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of an image reading apparatus that photoelectrically reads a document image or the like photographed on an image recording medium such as a film, and more specifically, a noise component such as a silver component remaining on an image recording medium such as a film. The present invention relates to an image reading apparatus and an image reading method that can detect and prevent adverse effects thereof.
[0002]
[Prior art]
At present, printing of an image taken on a photographic film (hereinafter referred to as a film) such as a negative film or a reversal film onto a photosensitive material (photographic paper) is performed by projecting an image of the film onto the photosensitive material and exposing the film. Exposure is mainstream.
In recent years, an image recorded on a film is photoelectrically read, and the read image is converted into a digital signal, and then subjected to various image processing to obtain image data for recording, which is modulated in accordance with the image data. Digital photo printers that expose a photosensitive material with recording light and output it as a print have also been put into practical use.
[0003]
According to such a digital photo printer, since an image photographed on a film is read and image processing is performed as digital image data, not only color and density can be corrected very suitably, but also gradation correction and sharpness processing. Image processing that is basically impossible with a normal direct exposure printer, such as (sharpness correction), can be performed to obtain a high-quality image.
In digital photo printers, not only printing but also outputting image data as an image file to a recording medium such as a CD-R or HD (hard disk) is performed.
[0004]
Incidentally, a silver component (hereinafter referred to as “residual silver”) remaining in an image of a developed (silver salt photograph) film is known as a cause of a decrease in image quality of a printed image in these photographic printers.
[0005]
[Problems to be solved by the invention]
The so-called color film is basically designed such that all the silver component present is removed by the bleaching and fixing processes performed after the color development / development process.
However, if the processing is not performed properly due to deterioration of the processing solution, temperature control, etc., a defect in the bleaching or fixing process occurs, and the silver component cannot be removed, resulting in residual silver. End up.
[0006]
If residual silver is present in the image, various image quality degradations occur, such as the tone of the high density portion (highlight on the print) becoming stiff and the saturation being lowered.
Therefore, in order to create a print on which a high-quality image is reproduced, it is necessary to prevent the adverse effects of residual silver. However, at present, there is no effective method other than appropriately managing the bleaching process and the fixing process in the developing process of the film so that residual silver does not remain in the image.
In addition, image quality deterioration occurs in the same way when impurities remain in the image recording medium as well as the image forming intermediate product of the image recording medium such as residual silver remaining in the film. In addition, there is no effective method other than preventing impurities from remaining in the image.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems of the prior art, and is an image reading apparatus and an image reading method for photoelectrically reading a document image or the like photographed or recorded on an image recording medium such as a (photo) film. In addition to image components caused by at least one of image formation intermediates such as residual silver and impurities remaining in an original image recorded on an image recording medium such as a silver salt photographic light-sensitive material such as a film or photographic paper Unnecessary (signal) components can be detected properly, or further, image quality correction due to unnecessary (signal) components such as residual silver can be corrected by image processing, and as a result, film and printing The development time of silver halide photographic light-sensitive materials such as paper can be shortened, margins can be given to processing conditions in the developing device, and image reading that enables suitable management of the developing device, etc. To provide an apparatus and an image reading method.
[0008]
[Means for Solving the Problems]
  In order to solve the above-described problems, the present invention provides an image reading apparatus that photoelectrically reads an original image including a visible image and an invisible image, the original imageMore than oneVisible and invisible light, And image information for each irradiated lightRead image reading means and read by the image reading meansThe visible light signal and the non-visible light signal of the image information are associated with each image position, the visible light signal having the same visible image density is extracted from the image information, and the non-visible light signal having the same position as the extracted visible light signal is extracted. A visible light signal is extracted, a lowest density non-visible light signal is detected from the extracted non-visible light signals, and the detected lowest density non-visible light signal and a non-visible light signal inherent in the document image The difference in the visible image density from which the visible light signal is extractedThe original imageAs silver component remaining inAn image reading apparatus having a detecting means for detecting is provided.
[0009]
  Further, the image reading means reads the visible image of the document image by reading the visible light of the three primary colors of red, green and blue.
  The detection means is a weighted visible light signal obtained by weighting the three primary colors of red, green and blue with a predetermined weight.And the invisible light signal are associated with each image position, and the weighted visible light signal having the same concentration of the weighted visible light signal is extracted from the image information.The weighted visible light signal is preferably obtained by performing a weighting operation for decreasing the weight in the order of red, green and blue.
[0010]
  Further, the present invention is the above image reading apparatus, further comprising the detection unit detected by the detection unit.Remaining silverDepending on the ingredients,Correct the influence of the remaining silver componentIt is an object of the present invention to provide an image reading apparatus comprising correction means for generating correction information and using the correction information to correct the visible light signal read by the image reading means.
  Here, the correction of the visible light signal by the correction means is theRemaining silverCorrecting at least one of a change in gradation and color reproducibility due to a component by image signal processing, orRemaining silverIn order to correct the change in graininess caused by the components, it is preferable to change the intensity of graininess suppression in the image signal processing. Also,The correction of the visible light signal by the correcting means corrects at least one of the gradation and the color reproducibility change caused by the remaining silver component by image signal processing, and the granularity caused by the remaining silver component. It is also preferable to change the intensity of graininess suppression in the image signal processing in order to correct the change in nature.
  Further, it is preferable that the correction unit generates the correction information on the basis of the invisible light signal having the lowest density in a set of pixels having the same visible light signal.
[0011]
  In addition, the present invention is an image reading apparatus, and further, the detection unit detects the detection unit.Remaining silverIt is an object of the present invention to provide an image reading apparatus having warning means for outputting a warning to the effect that the amount of a component is higher than a predetermined value.
  In addition, in order to solve the above problems, the present invention provides:An image reading method for photoelectrically reading a film document image created by performing color development / development processing on a film on which a document image is recorded and then performing bleaching processing and fixing processing, wherein the film document image includes a plurality of visible images. A visible light image information reading step for irradiating light and reading image information for each irradiated visible light; and a non-visible light image information reading step for irradiating the film original image with invisible light to read invisible light image information. A visible light signal of the image information read in the visible light image information reading step and a non-visible light signal of the image information read in the non-visible light image information reading step for each image position, and the visible light image information A visible light signal having the same visible image density is extracted from the image information read in the reading step, and a non-visible light signal at the same position as the extracted visible light signal is extracted and extracted. The invisible light signal having the lowest density is detected from the visible light signal, and the difference between the detected invisible light signal having the lowest density and the invisible light signal inherent in the film original image is extracted. A remaining silver detecting step for detecting as a remaining silver component of the film original image at a visible image density.A characteristic image reading method is provided.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
An image reading apparatus and an image reading method according to the present invention will be described below in detail based on preferred embodiments shown in the accompanying drawings.
[0013]
FIG. 1 is a block diagram showing an embodiment of a digital photo print system using the image reading apparatus of the present invention.
A digital photo print system (hereinafter referred to as a print system) 10 shown in FIG. 1 photoelectrically reads an image photographed on a (photo) film F and outputs it as a (photo) print. The scanner 12, the image processing unit 14, the display 18, the operation system 20 (keyboard 20 a and mouse 20 b), and a printer 22 are included.
[0014]
The scanner 12 is a device that photoelectrically reads an image shot on each frame of the film F, and as shown in the conceptual diagram of FIG. 2, the light source 24, the driver 26, the diffusion box 28, the carrier 30, and the imaging lens. It has a unit 32, a reading unit 34, an amplifier (amplifier) 36, and an A / D (analog / digital) converter 38.
[0015]
In the scanner 12 of the illustrated example, the light source 24 uses an LED (Light Emitting Diode), and emits three types of visible light of R (red) light, G (green) light, and B (blue) light. An LED and an LED that emits IR (infrared) light, which is invisible light, are arranged and configured. Such a light source 24 is driven by a driver 26, and each visible light and IR light are emitted sequentially.
The diffusion box 28 makes light incident on the film F uniform in the surface direction of the film F.
[0016]
The carrier 30 intermittently conveys the film F and sequentially conveys / holds each image (each frame) photographed on the film F to a predetermined reading position. A plurality of types of carriers 30 corresponding to the film size and the like are prepared, and are configured to be detachable from the main body of the scanner 12.
In the illustrated example, the carrier 30 includes a pair of transport rollers 40a and 40b that transport the film F in the longitudinal direction, and a mask 42 that regulates the reading area of each frame at a predetermined reading position. Have
[0017]
The imaging lens unit 32 focuses the projected light of the film F on a predetermined position of the reading unit 34.
The reading unit 34 photoelectrically reads an image photographed on the film F using an area CCD sensor, and reads the entire surface of one frame regulated by the mask 42 of the carrier 30 (image reading by surface exposure). ).
[0018]
In such a scanner 12, when reading the film F, first, the film F is conveyed by the carrier 30, and a frame to be read (usually the first frame or the last frame) is conveyed to the reading position.
Next, under the action of the driver 26, for example, the R LED of the light source 24 is driven to emit R light. The R light is made uniform in the surface direction of the film F by the diffusion box 28, then enters the reading position, enters and passes through the frame held here, and the image photographed on this frame is captured. The projection light is carried. This projection light is imaged at a predetermined position (light receiving surface of the area CCD sensor) of the reading unit 34 by the imaging lens unit 32, and the R image of this frame is photoelectrically read.
[0019]
Similarly, the G and B LEDs of the light source 24 are sequentially emitted to read the G image and B image of this frame, and finally the IR LED of the light source 24 is emitted to read by IR. (IR image reading) is performed, and reading of this frame is completed. Accordingly, the scanner 12 has four channels of image data (visible light signal) of each of R, G, and B visible images and image data (non-visible light signal) of an IR image (non-visible image). Image data is output.
When the reading of one frame is completed, the carrier 30 conveys the film F and conveys the next frame to be read to the reading position.
[0020]
Output data from the reading unit 34 is amplified by an amplifier 36, converted into digital data by an A / D converter 38, and output to the image processing unit 14 (data correction unit 44).
[0021]
In the present invention, the image reading means is not limited to the illustrated scanner 12. For example, by using a white light source such as a halogen lamp instead of four color LEDs and providing R, G, B, and IR filter insertion means upstream of the diffusion box 28, an image photographed on the film can be similarly obtained. You may read by 4 channels. Alternatively, using a white light source and a 4-line CCD sensor that reads R, G, B, and IR images, so-called slit scanning is used to read an image taken on a film with the same four channels. Also good.
[0022]
In the print system 10, a fine scan for reading an image at a high resolution for printing or the like for each frame and a fine scan reading condition and an image processing condition in the image processing unit 14 are usually determined. Prior to scanning, two image readings are performed, that is, pre-scanning, which is image reading at a low resolution.
In this case, normally, the output signals of the pre-scan and fine scan are basically the same data except that the resolution and the output level are different.
[0023]
As described above, the digital image signal output from the scanner 12 is output to the image processing unit 14. FIG. 3 shows a block diagram of the image processing unit 14.
As shown in FIG. 3, the image processing unit 14 includes a data correction unit 44, a log converter 46, a frame memory 48 (hereinafter referred to as FM 48), a residual silver detection and correction unit 50, an image correction unit 54, and data. A conversion unit (3D-LUT) 58 is included.
[0024]
Although not shown, the image processing unit 14 of the print system 10 processes pre-scan data and displays a simulation image for verification on the display 20, in the downstream of the data flow direction from the Log converter 46 ( In the following, it branches downstream) and has a processing path basically similar to that of the FM 48 to the data converter 58. In this processing path, the residual silver detection and correction unit 50 may or may not be included.
[0025]
The data correction unit 44 is a part that performs predetermined correction such as DC offset correction, dark correction, and shading correction on the data of the R, G, B, and IR images output from the scanner 12.
The Log converter 46 performs Log conversion on the data processed by the data correction unit 44 using, for example, an LUT (Look Up Table) or the like to obtain digital image (density) data.
The image data of R, G, B, and IR images converted by the Log converter 46 is stored in the corresponding FM 48, respectively.
[0026]
The image data stored in the FM 48 is processed by the residual silver detection and correction unit 50.
The residual silver detection and correction unit 50 includes image data (hereinafter, referred to as visible image data) of visible images of the three primary colors R, G, and B, and image data of IR images (non-visible images) ( (Hereinafter referred to as IR data) is used to detect residual silver (residual silver component) in the image photographed on film F, and to remove the detected residual silver as necessary. The visual image data is corrected, and if necessary, if the amount of residual silver is larger than a predetermined amount, a warning to that effect is given.
[0027]
  The film F that forms an image by silver salt photography is basically designed so that all the silver component present is removed by the bleaching and fixing processes performed after the color development / development process. However, if a defect in the bleaching process occurs due to various factors such as deterioration of the processing solution, an intermediate image formation such as residual silver in the image (film F)GenerationUnnecessary components such as objects and impurities, that is, noise components remain, and as a result, gradation and color reproducibility deteriorate, for example, gradation in a high density portion becomes hard (high tone), As described above, various inconveniences such as a decrease in saturation or a deterioration in graininess, that is, a rough feeling in an image remain.
  Further, according to the study of the present inventor, in the case of a negative film, depending on the limit of the processing solution, it remains in the high density part (the high brightness part of the shooting scene) rather than the low density to medium density area. Noise components such as silver and impurities often remain.
[0028]
Here, if the digital image data read photoelectrically, noise components such as residual silver and impurities in the image can be detected properly, and image processing will increase the contrast and decrease the saturation of the high-density area due to the residual silver. There is a high possibility that adverse effects such as deterioration of gradation and color reproducibility, etc., and deterioration of graininess can be corrected.
In response to this, the present inventor conducted extensive studies on a method for detecting noise components such as residual silver in an image, and as a result, invisible light such as IR light is present in an image (a dye forming an image). It is not absorbed and is absorbed by noise components such as residual silver. From the correlated pixel distribution between a visible image and a non-visible image read photoelectrically, noise such as residual silver in the image It was found that the components can be detected properly. Hereinafter, although residual silver will be described as a representative example as a noise component, it is needless to say that the present invention is not limited to this.
[0029]
FIG. 4 shows an example of correlation between the density of the visible image (image data) and the density of the IR image (image data) for each pixel of an image.
In FIG. 4, (A) shows the R concentration (D_R) And IR concentration (D_IR), (B) is the G concentration (D_G) And IR concentration (D_IR), (C) is the B concentration (D_B) And IR concentration (D_IR) Are shown respectively.
FIG. 4D also shows the overall density (D) of the visible image as a full-color image, including all visible images of R, G and B._V) And IR concentration (D_IR).
[0030]
The overall density D_VThere is no particular limitation on the calculation method of, and various calculation methods used in image processing can be used.
D_V= ΑD_R+ ΒD_G+ ΓD_B
What is necessary is just to calculate by this weighting calculation.
Here, α, β, and γ are weighting factors, and may be appropriately determined according to the apparatus characteristics, film type, and the like. However, when the film F is a negative film, the R photosensitive layer is usually the most. Below, since the B photosensitive layer is at the top, considering the detergency of the silver component due to the layer structure, α, β and γ are reduced in this order, that is, “α> β> γ”. Is preferred.
[0031]
As shown in FIG. 4, the R concentration (D_R), G concentration (D_G), B concentration (D_B) And overall concentration (D_V) In any visible image density, the IR density (D_IR) The minimum line is going up.
IR light is not absorbed by the image (dye), so if there is no residual silver, the IR concentration, ie D_IRRegardless of the visible image density, it should be a predetermined density corresponding to the intrinsic IR density (IR absorption amount) of the film F, that is, a straight line (dotted line C in the figure). Therefore, it can be considered that the lowest IR density line above the dotted line C is the IR density caused by the residual silver.
In addition, it is considered that the pixels above the lowest line are generated as IR density due to diffusion of IR light due to dust or scratches adhering to the film to reduce the amount of light.
Therefore, the read IR density D_IRAre the intrinsic IR density C that the film basically has and the IR density D caused by residual silver._AgAnd IR density D caused by dust or scratches attached to the film_deCan be expressed by the following formula.
D_IR= D_Ag+ D_de+ C
[0032]
If the residual silver has an influence on the IR density, the visible image density should have the same influence, that is, the IR density (D of the same pixel (image position))._IR) And visible image density (D_R, D_G, D_B, D_V) Should have a correlation. Also, as mentioned above, there is no dust on the film (D_de= 0), D_IR= D_AgSince it is + C, the lowest IR density D in the pixel group having the same visible image density even if there is dust or the like_IRIs considered to be the sum of IR density and intrinsic IR density C due to residual silver at this visible image density.
Therefore, this lowest IR concentration D_IRFrom FIG. 4, if the intrinsic IR density C originally possessed by the film itself indicated by the dotted line C is subtracted, the IR density D caused by residual silver_AgThe residual silver component in the visible image photographed on the film F can be detected.
Here, a pixel having the same visible image density means each visible image density (D_R, D_G, D_B, D_V) Are pixels having the same value. The overall concentration (D_V), The total density (D_V) As well as a group of pixels having the same density (D, R, G, B)_R, D_G, D_B) May be a group of pixels having the same color density, that is, only pixels having the same color density.
[0033]
Using the detected residual silver component, the visible image data is corrected, or the visible image data in gradation conversion, color (saturation) correction, (granularity suppression) sharpness processing, etc. in the image correction unit 54 described later is used. By changing the processing parameters, the adverse effects caused by the residual silver remaining in the image on the film F are corrected, and the gradation / color reproducibility deterioration and graininess deterioration such as highlight enhancement and saturation reduction. High-quality images can be output.
Moreover, since the deterioration of processing solutions such as bleaching solutions and excessive bleaching processing can be detected from the detected amount of residual silver components, the development device does not have a dedicated maintenance tool such as a concentration meter. Thus, it is possible to properly manage the processing solution and shorten the processing time, that is, the development time, particularly the bleaching time.
[0034]
Hereinafter, the processing in the residual silver detection and correction unit 50 will be specifically described with reference to FIG.
As described above, when the R, G, and B visible image data and the IR data are stored in the FM 48, the residual silver detection and correction unit 50 reads both, and first, all the pixels (x_i, Y_i), As shown in FIG. 4D, RGB (x) which is the entire visible image data including all visible images of R, G, and B_i, Y_i) And IR (x_i, Y_i) To obtain a pixel distribution correlated with
Note that RGB (x_i, Y_i) Is, for example, the above-mentioned formula “D_V= ΑD_R+ ΒD_G+ ΓD_BCan be obtained.
[0035]
Next, the residual silver detection and correction unit 50 uses the same RGB (x_i, Y_i) Is detected in the pixel set having the minimum IR data, and this is detected as MinIR [RGB (x_g, Y_g)]. That is, this MinIR [RGB (x_g, Y_g)] Is the IR concentration D in FIG._IRIs the lowest line.
[0036]
Furthermore, MinIR [RGB (x_g, Y_g)] Is obtained, this MinIR [RGB (x_g, Y_g)], The intrinsic density value C which is basically the intrinsic IR density of the film F (IR density D indicated by the dotted line C in FIGS. 4A to 4D)._IRThe residual silver image Ag_Image(X_g, Y_g) Is calculated.
That is,
Ag_Image(X_g, Y_g) = MinIR [RGB (x_g, Y_g)]-C
Residual silver image Ag_Image(X_g, Y_g) May be stored as a table for each pixel set g, or F [Ag_Image(X_g, Y_g)].
[0037]
Here, residual silver image Ag_Image(X_g, Y_g) Is greater than the predetermined value, the residual silver detection and correction unit 50 outputs a message to that effect to the control unit of the image processing unit 14. Receiving this, the image processing unit 14 warns that there is a large amount of residual silver on the film F by a warning sound or display on the display 18.
[0038]
Residual silver image Ag_Image(X_g, Y_g) Is used as a correction coefficient, and each pixel (x_i, Y_i) R, G, and B visible image data of the residual silver image Ag of the corresponding pixel set_Image(X_g, Y_g) To obtain corrected visible image data R ′, G ′ and B ′. That is,
R '(x_i, Y_i) = R (x_i, Y_i) -Ag_Image(X_g, Y_g)
G ’(x_i, Y_i) = G (x_i, Y_i) -Ag_Image(X_g, Y_g)
B ’(x_i, Y_i) = B (x_i, Y_i) -Ag_Image(X_g, Y_g)
The residual silver detection and correction unit 50 sends the corrected visible image data R ′, G ′, and B ′ calculated in this way to the next image correction unit 54.
[0039]
In the above example, processing is performed using the overall image density RGB corresponding to a full-color visible image, but in addition to this, a visible image of one color, for example, each color of R, G, and B is used. For each data, the residual silver image Ag is obtained from the correlation between the visible image data of each color and the IR data._ImageIn the same manner, the visible image data may be corrected.
However, the residual silver has an effect on the image data of all colors and the amount of calculation increases, so that one overall visible image including all the data of the three primary colors as in the above example. Data RGB (x_i, Y_i) To detect residual silver.
[0040]
As described above, the R, G, and B visible image data whose residual silver components have been corrected by the residual silver detection and correction unit 50 are then processed by the image correction unit 54.
The image correction unit 54 is a part that performs various types of image processing performed in a digital printing system. Examples of the image correction unit 54 include image scaling processing (electronic scaling processing), sharpness (sharpness enhancement) processing, and density correction processing. Image processing such as color correction (saturation correction) processing, dodging processing (image density dynamic range expansion / contraction processing), gradation conversion, and the like is performed.
[0041]
Here, in this example, the residual silver detection and correction unit 50 corrects the adverse effect due to the residual silver in the image photographed on the film F by correcting the visible image data according to the extracted residual silver component. is doing.
However, the present invention is not limited to this, the residual silver detection and correction unit 50 only detects the residual silver component, and the image correction unit 54 performs gradation conversion or the like according to the detected residual silver component. You may correct the bad influence by residual silver by changing image processing parameters, such as color (saturation) correction and sharpness (grain suppression) processing, and performing image processing.
[0042]
That is, the correction of the visible image data of R, G, and B in the present invention may be performed by the residual silver detection and correction unit 50 or the image correction unit 54.
The correction of the visible image data may be correction of at least one of gradation and color reproducibility caused by noise components such as a residual silver component, particularly deterioration by image processing, or residual In order to correct a change in graininess caused by a noise component such as a silver component, particularly a deterioration, the strength of graininess suppression in image processing may be changed, that is, increased.
[0043]
Here, when correcting the gradation as the correction of the visible image data, it can be performed as follows.
For example, in image reading from a normal film image having no residual silver, as shown in the graph (straight line) a in FIG. 6A, the read signal (image data) and the density of the dye image of each color of the film image Is a linear relationship (linear function). On the other hand, if there is residual silver, as shown in the graph (curve) b in FIG. 6 (B), it is affected by the residual silver in the high density region of the dye image density and deviates from the linear relationship. The read signal value larger than the normal read signal value is read out from the straight line “a” and is hardened. A portion shifted upward from the straight line a in the graph b is an increase d due to the residual silver component. This is as described above.
[0044]
  Therefore, as described above, in order to remove the increase d due to the residual silver, the graph shown in FIG.cA corrected signal (corrected image data) can be obtained by using a curve having a characteristic opposite to that of the graph b as a correction curve (correction table) of the read signal (image data).
  Thus, even when the density of the dye image of each color is read from a film image having residual silver, a corrected signal (image data) that is not affected by the residual silver component and is equal to a normal read signal value can be obtained.
  The gradation correction may be performed by the residual silver detection and correction unit 50 as described above, or may be performed by density correction processing or gradation conversion processing in the image correction unit 54.
[0045]
Further, when correcting color reproducibility as correction of visible image data, saturation reduction due to residual silver is corrected by enhancing the saturation by matrix processing. For example, when the image correction unit 54 performs color correction or saturation correction by matrix processing, the processing parameters are increased in saturation emphasis intensity, and the image data before correction is processed by saturation emphasis matrix processing. It is possible to obtain corrected image data that is not affected by the decrease in saturation due to. The correction of the color reproducibility may be performed not by the image correction unit 54 but by the residual silver detection and correction unit 50.
[0046]
Furthermore, as a correction of the visible image data, it is possible to correct the deterioration of graininess due to the residual silver component. In this case, for example, the granularity suppression strength in the sharpness (sharpness enhancement) processing in the image correction unit 54 is increased (or further, the sharpness strength is decreased), or the granularity suppression strength is increased and the granularity suppression is performed. By performing the processing, it is possible to obtain corrected image data that is not affected by the deterioration of graininess due to residual silver. Of course, the correction of the graininess may be performed not by the image correction unit 54 but by the residual silver detection and correction unit 50.
[0047]
The processed visible image data that has been subjected to various types of image processing by the image correction unit 54 is output to the data conversion unit 58.
The data converter 58 converts the visible image data using, for example, a three-dimensional (3D) -LUT, and outputs the converted image data to the printer 22 as output image data corresponding to the print output in the printer 22.
In the print system 10, the visible image data processed by the image correction unit 54 is converted into an image file of various image formats, for example, JPEG format, and the image file is a CD-R, MD (mini disc), or the like. May be output to a recording medium, and both a print and an image file may be output.
[0048]
The printer 22 is a known color printer, for example, by scanning and exposing a photographic paper two-dimensionally with a laser beam modulated according to supplied R, G and B output image data, and recording a latent image. The exposed photosensitive material is subjected to a wet development process of development / fixing / washing to visualize the latent image, and then dried and output as a print.
[0049]
In the above example, both the correction of the visible image and the warning that there is a large amount of residual silver are performed according to the detected residual silver. However, the present invention is not limited to this, and the correction of the visible image is performed. And only one of the warning generation may be performed, or the detected residual silver amount may be output (only this output or in combination with other processing).
[0050]
  Further, in the above example, image reading was performed on a film, and noise components such as residual silver were detected or image quality deterioration due to noise components was further corrected. However, the present invention is not limited to this. The present invention can also be suitably used for image reading for image recording media such as photographic paper.
  Further, in the above example, image reading is performed on the image recording medium to detect noise components such as residual silver, or further to correct image quality degradation caused by noise components. However, the present invention is not limited to this. Detection and correction of image defects caused by dust scratchesgoOf course it is also good. In the case of detection of dust scratches, read IR density D_IRTo IR concentration D due to residual silver_AgBy subtracting, the IR density D caused by dust flaws_deIR concentration D_deFor example, the IR density D is larger than a predetermined threshold value._deWhat is necessary is just to determine a pixel having a dust scratch.
[0051]
Specifically, in the above-described example, the pixel (x_i, Y_i) Read IR image data IR (x_i, Y_i) Residual silver image Ag_Image(X_g, Y_g) Is subtracted from the corrected IR image data IR ′ (x_i, Y_i) And the corrected IR image data IR ′ (x_i, Y_i) To determine dust scratches.
IR ’(x_i, Y_i) = IR (x_i, Y_i) -Ag_Image(X_g, Y_g)
[0052]
Here, when a pixel having a dust scratch is detected, the visible image is corrected using the address information of the pixel, that is, the visible image data of R, G, and B is corrected, and there is no dust scratch. An image. Note that there is no particular limitation on a method for correcting a visible image having dust flaws, and various known methods such as correction by interpolation and correction using pixel continuity can be used.
[0053]
The image reading apparatus and the image reading method of the present invention have been described above in detail. However, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be made without departing from the scope of the present invention. Of course it is good.
[0054]
【The invention's effect】
  As described above in detail, according to the present invention, in an image reading that photoelectrically reads an image or the like taken or recorded on an image recording medium such as a film or a photographic paper, the silver component and the like remaining in the image Image formation intermediateGenerationUnnecessary components such as objects and impurities can be properly detected.
  Therefore, according to the present invention, by correcting the image data in accordance with the detected unnecessary component such as residual silver, the high density portion of the image due to the unnecessary component such as residual silver is increased in contrast and the saturation is decreased. It is possible to output high-quality images with no deterioration in gradation and color reproducibility, or with no deterioration in graininess, and grasp the state of the processing solution according to the detected residual silver etc. Thus, maintenance of the developing device can be performed properly.
  Furthermore, according to the present invention, the processing time of the silver salt photographic light-sensitive material such as film or photographic paper in the developing device, that is, the developing time, particularly the bleaching time can be shortened, and the processing condition in the developing device is given a margin. be able to.
[Brief description of the drawings]
FIG. 1 is a block diagram of an example of a digital print system that uses an image reading apparatus of the present invention.
FIG. 2 is a conceptual diagram of a scanner of the digital photo print system shown in FIG.
FIG. 3 is a block diagram of an image processing unit of the digital photo print system shown in FIG.
4A, 4B, 4C, and 4D are graphs for explaining detection of residual silver in the present invention, respectively.
FIG. 5 is a flowchart for explaining residual silver detection and correction processing according to the present invention.
FIGS. 6A, 6B and 6C are graphs for explaining correction of gradation deterioration caused by residual silver in the present invention.
[Explanation of symbols]
10 (Digital Photo) Print System
12 Scanner
14 Image processing unit
18 display
20 Operation system
22 Printer
24 Light source
26 Driver
28 Diffusion box
30 career
32 Imaging lens unit
34 Reading unit
36 amplifiers
38 A / D converter
40 Conveying roller pair
42 Mask
44 Data correction unit
46 Log Converter
48 FM (frame memory)
50 Residual silver detection and correction unit
54 Image correction unit
58 Data converter

Claims (9)

An image reading device that photoelectrically reads a document image including a visible image and a non-visible image,
Image reading means for irradiating the document image with a plurality of visible light and invisible light , respectively, and reading image information for each of the irradiated light ;
The visible light signal and the invisible light signal of the image information read by the image reading unit are associated with each image position, and a visible light signal having the same visible image density is extracted from the image information and extracted. Extract the invisible light signal at the same position as the visible light signal, detect the invisible light signal with the lowest density from the extracted invisible light signal, and the original image with the lowest density invisible light signal detected An image reading apparatus comprising: detecting means for detecting a difference from the invisible light signal included in the image as a silver component remaining in the original image at a visible image density obtained by extracting the visible light signal . The image reading means reads the visible image of the document image by reading the visible light of the three primary colors of red, green and blue.
The detection means associates a weighted visible light signal and a non-visible light signal obtained by performing a weighting operation with predetermined weighting on the three primary colors of red, green, and blue for each image position, and The image reading apparatus according to claim 1 , wherein weighted visible light signals having the same density of the weighted visible light signal are extracted from the image information . The image reading apparatus according to claim 2 , wherein the weighted visible light signal is obtained by performing a weighting operation for decreasing weighting in the order of the red, green, and blue. The image reading apparatus according to any one of claims 1 to 3 ,
Further, according to the remaining silver component detected by the detection means, correction information for correcting the influence of the remaining silver component is generated, and the correction information is used to read the image read by the image reading means. An image reading apparatus comprising correction means for correcting a visible light signal. The image reading apparatus according to claim 4 , wherein the correction of the visible light signal by the correction unit is to correct at least one of a change in gradation and color reproducibility due to the remaining silver component by image signal processing. . The correction of the visible light signal by the correction means, in order to modify the granularity of the change due to the silver component to the remaining, it is to vary the intensity of graininess suppression in the image signal processing according to claim 4 Image reading device.   The correction of the visible light signal by the correcting means corrects at least one of the gradation and the color reproducibility change caused by the remaining silver component by image signal processing, and the granularity caused by the remaining silver component. The image reading apparatus according to claim 4, wherein the intensity of graininess suppression in the image signal processing is changed in order to correct the change in property. An image reading apparatus according to any one of claims 1 to 7
The image reading apparatus further comprises warning means for outputting a warning to that effect when the amount of the remaining silver component detected by the detecting means is higher than a predetermined value. An image reading method for photoelectrically reading a film document image created by performing color development / development processing on a film on which a document image is recorded, and then performing bleaching processing and fixing processing,
A visible light image information reading step of irradiating the film document image with a plurality of visible lights and reading image information for each irradiated visible light;
Irradiating the invisible light to the film original image, the invisible light image information reading step of reading image information of the non-visible light,
A visible light signal of the image information read in the visible light image information reading step and a non-visible light signal of the image information read in the non-visible light image information reading step are associated for each image position, and the visible light image information reading step Extract the visible light signal with the same visible image density from the image information read in step 1, extract the non-visible light signal at the same position as the extracted visible light signal, and extract the lowest density from the extracted non-visible light signal The invisible light signal is detected, and the difference between the detected invisible light signal having the lowest density and the invisible light signal inherent in the film original image is the film original at the visible image density obtained by extracting the visible light signal. An image reading method comprising: a remaining silver detecting step for detecting as a remaining silver component of an image.

Images