JPH0951433A - Digital image recording method, its device and digital image processing unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a high quality reproduction image with less dispersion among photo prints by deciding a control variable of an image signal based on an image recording basic amount and each image signal and recording the image. SOLUTION: Image data from an image input section 10 are tentatively written in an image memory 50, and a basic amount arithmetic section 51 reading the data obtains an image recording basic amount for each image density for each original image and gives the amount to a recording image information arithmetic section 52. The arithmetic section 52 calculates recording image information to decide a projected luminous multi-value processing of each picture element while correcting various daily fluctuation of a negative original or a positive original or the like and gives the result to a data conversion section 53. The conversion section 53 obtains an image signal control variable from a conversion able deciding the image signal control variable on the condition of converting the recording image information into prescribed image density and an image recording section 12 records the control variable. Thus, a high quality reproduction image with features of digital image processing and the surface exposure system of a photo print is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for digitally image-processing an image signal obtained from a photographic original or an image signal of an electronic still camera or the like, and an image processing method, and particularly from a photographic film. The present invention relates to a digital image recording method and apparatus for recording an image on various recording papers based on an obtained digital image signal, and an image processing apparatus.

[0002]

2. Description of the Related Art An image signal control amount is obtained based on an image signal obtained by imaging a reflection original such as a print photograph or a photographic film, and an image reproduced on a color photosensitive material or other recording medium based on the image signal control amount. In the conventional digital recording method of recording, the reproduction point is obtained by controlling the highlight point and the shadow point of the original image so as to become the highlight point and the shadow point of the reproduced image. For example, JP-A-56-87044 discloses a highlight point in an original image,
The shadow points are calculated, the reproduction densities for these points are set, and the gradation reproduction characteristics that connect both reproduction densities are calculated. Also, JP-A-59-15939 and JP-A-62-72.
No. 90, JP-A-2-236786 and the like describe that the highlight point and the shadow point of a document are more appropriately obtained. Furthermore, JP-A-6-24252
Japanese Patent No. 1 discloses that the maximum value and the minimum value are used instead of the highlight point and the shadow point. Further, Japanese Patent Laid-Open No. 6-301123 describes that a shadow point is estimated from an unexposed portion of a document.

Further, a test step tablet is prepared by using a known light quantity control signal, the tablet is measured by a photometric device to obtain a density signal, and the density signal and the light quantity control signal are compared to obtain a gradation table. Is disclosed in JP-A-6-311365.

Further, Japanese Patent Laid-Open No. 61-238174 discloses that a cumulative density histogram of an image signal is obtained and compared with a predetermined cumulative density histogram to find a gradation correction signal for obtaining an optimum gradation. Has been described. Also,
As a method for creating a conversion curve based on a cumulative histogram, there is JP-A-6-178113. Further, a device for obtaining a highlight point and a shadow point from a cumulative density histogram (JP-A-1-253366) and a device using the cumulative histogram (JP-A-5-91324)
Are also proposed.

Also, a plurality of standard patterns and standard tone reproduction curves are stored and the standard tone reproduction curve is selected according to the matching of the original pattern and the standard pattern (Japanese Patent Laid-Open No. 58-5744), A method of correcting the reference reproduction curve by an image and using it (Japanese Patent Laid-Open No. 60-2163).
50, JP-A-2-12244, JP-A-6-
178104, etc.) has been proposed.

As described above, in almost all conventional digital image recording methods, the highlight points and shadow points of the original image are controlled to become the highlight points and shadow points of the reproduced image. Therefore, it has a conversion table of the image recording signal (output) for the digital image signal (input) so that the image recording signal for the digital image signal becomes a signal corresponding to white and black, a highlight point of density, and a shadow point. A conversion table is created or a conversion table is created using a cumulative density histogram.

In order to eliminate the inconvenience such as the color fog at the highlight point and the shadow point, the method for determining the highlight point and the shadow point is devised, the tone reproduction curve is corrected by a cumulative density histogram, and Proposals have been made (for example, JP-A-60-216350 and JP-A-62-111569) to improve the reproducibility of the intermediate density range by adding specific points in the density range. Most of these have been used for image recording of printing using a reversal film as an original, and did not reproduce the image recorded on the negative film.
Further, as a target for a negative film, Japanese Patent Application Laid-Open No.
In Japanese Patent Laid-Open No. -311365, a histogram is modified to obtain an image representative value and a conversion table is created from the image representative value and the conversion curve, but there is no specific description about the method of creating the conversion table.

[0008]

Since the reversal film has a narrow exposure latitude, many originals tend to be white near the base density of the film at the highlight points and black near the maximum density of the film at the shadow points. It is also possible to determine the exposure at the time of shooting so that the print document is intended to have a highlight point and a shadow point. However, the negative film has the following disadvantages, unlike the reversal film, because the exposure latitude is wider than that of the reversal film. The exposure latitude is wide, and particularly in a general negative film photographed by an amateur, the highlight is not necessarily white and the shadow point is not black on the color light-sensitive material using this. For example, a blue sky or a portrait image without a white point fails in color reproduction. Also, in the background of garden trees, shadow points are often dark green instead of black. If the background is a wall or furniture with a strobe light and the background is colored, the shadow points will be colored. As described above, in the image processing for the reversal film as described above, a good reproduced image may not be obtained in some cases. Image recording of a high-brightness sky, a scene near a window, or a scene with specular reflection light makes the main subject black, and even in a stroboscopic shooting scene, the face density to be reproduced changes depending on the difference between the face density of a person and the background density. The image recording method using the highlight point and the shadow point only changes the gradation of the copied image according to the contrast of the original image so that the density reproduction area of the copy material includes the highlight point and the shadow point at the same time. , Some images do not have sufficient quality. Such image correction has a drawback that the highlight portion and the shadow portion which are not necessarily required are reproduced, and an unnatural gradation correction is performed by reproducing the highlight portion and the shadow portion. On the other hand, a reproduction image in which a negative film is irradiated with printing light and an image is printed on the color light-sensitive material with the light passing through the negative film depends on the gradation of the color light-sensitive material, but it is reproduced as it is on the film. Therefore, the image becomes a natural image close to reality.

The print quality of the latest color negative film photographic printing apparatus is high and stable. Most of these images are not of special value for printing with digital image processing to modify the image signal. Imperfect correction of the image signal causes variations in print quality and, conversely, lower quality than surface exposure printing.

The present invention provides a novel digital image recording method which is different from the method of recording an image based on each point of highlight and shadow in an original image having the above-mentioned drawbacks and the cumulative density histogram. With the goal. Also,
Another object of the present invention is to obtain stable reproduction quality comparable to surface exposure while using a digital image signal. Another object is to obtain an excellent reproduction quality of an image suitable for surface exposure from a digital image signal and to switch the reproduction method for an image not suitable for surface exposure to improve the yield of obtaining a good product. It is in. Another object is to obtain stable reproduction quality, which is a feature of surface exposure, while taking advantage of the advantages of digital image processing.

[0011]

In order to achieve the above object, a digital image recording method according to a first aspect of the present invention uses an image recording basic amount commonly used for each image signal according to an image feature amount obtained from the image signal. Then, an image signal control amount for each image signal is determined from the image recording basic amount and each image signal, and an image is recorded.

In the digital image recording method according to the second aspect, the image recording basic amount commonly used for each image signal is obtained from the image characteristic amount obtained from the image signal, and the image recording basic amount and each image signal are calculated. The recorded image information for each pixel for recording an image is obtained, and an LUT or a functional relationship indicating the relationship between the recorded image information and the image signal control amount necessary to obtain the recorded image density for this recorded image information is defined in advance. The image signal control amount is obtained from the recorded image information based on the above relationship, and the image is recorded.

According to a third aspect of the present invention, there is provided an image recording basic method commonly used for each image signal for recording an original image based on an image feature amount obtained from the image signal by a selection signal of the image recording method. The image signal control necessary to obtain the recorded image information for each pixel for recording an image from the image recording basic amount and each image signal, and obtain the recorded image information and the recorded image density for this recorded image information in advance. An image signal control amount is obtained from the recorded image information based on the LUT or a functional relation that indicates a relationship with the amount, and an image signal based on a highlight point and a shadow point according to the scene of the original image. The image recording method using the control amount and the image recording method using the image signal control amount based on the recorded image information are selectively used. The image characteristic amount includes at least an average value of image signals of all image portions or partial image portions, or at least an average value of selected image signals, and the image recording basic amount is a density control value for controlling image density and a color. And a color control value for controlling.

According to a fifth aspect of the present invention, there is provided an image recording basic amount calculating means for obtaining an image recording basic amount commonly used for each image signal based on an image characteristic amount obtained from the image signal, and an image recording basic amount. And an image signal control unit for calculating the recorded image information for each pixel from the image signals, and an LUT showing the relationship between the image signal control amount necessary to obtain the recorded image density for the recorded image information, or a functional relationship. And the image signal control amount conversion means for obtaining the image signal control amount from the recorded image information based on the above relationship.

According to a sixth aspect of the present invention, a digital image processing apparatus calculates an image recording basic amount commonly used for each image signal based on an image characteristic amount obtained from the image signal, and the image recording basic amount and each image signal are calculated. Image recording from the image signal by using the first image signal control amount calculating means for calculating the image signal control amount for image recording from the image recording table and the image recording table connecting the highlight image reference point and the shadow image reference point. Is provided with a second image signal control amount calculation means for calculating the image signal control amount and a selection means for selecting the first or second image signal control amount calculation means.

According to a seventh aspect of the present invention, there is provided a digital image recording apparatus according to the sixth aspect, wherein an image is recorded on the digital image processing apparatus according to the sixth aspect according to the image signal control amount from the image signal control amount calculating means selected by the selecting means. The image recording unit is provided.

[0017]

1 is a functional block diagram of a digital image recording apparatus embodying the present invention. This digital image recording apparatus includes an image input unit 10 and an image signal processing unit 1.
1, an image recording unit 12, a film information input unit 13, and a manual information input unit 14.

As shown in FIG. 2, the image input section 10 reads the image of the negative film 20 and converts it into an image signal. The film feeding section 21 and the negative film 20.
It includes a light source unit 22 for illuminating, a lens 23, a CCD (charge coupled device) line sensor 24, and a signal processing circuit 25. The light source unit 22 is provided with a slit plate 26, and irradiates the negative film 20 with reading light through a slit 26a formed long in a direction orthogonal to the feeding direction of the negative film 20. The image of the negative film 20 irradiated by the light source unit 22 is coupled to the light receiving surface of the photoelectric conversion element of the line sensor 24 via the lens 23 and read by the line sensor 24 line by line. The film feeding unit 21 feeds one line of film in synchronization with the reading of each line. The image input section 10 is an example, and in addition to this, a scanner, a still video camera, a television camera, a video deck, a personal computer, or the like can be used as the image input section.

The read image data is sent to the signal processing circuit 25 of the image input section 10. The signal processing circuit 25, after digitizing the photoelectric conversion signal from the line sensor 24 by the A / D converter, corrects characteristic variations of the respective light receiving elements of the line sensor 24 and performs shading correction.
Signal processing such as density conversion is also performed as necessary.

The image signal processing unit 11 converts the signal from the image input unit 10 into a recording control signal for recording an image. Therefore, the image signal processing unit 11 is connected to the film information input unit 13 and the manual information input unit 14. The film information input unit 13 inputs a film type, frame information, shooting information, print information, and the like. The manual information input unit 14 inputs instructions such as correction of print conditions.
Further, the image signal processing unit 11 reverses the image depending on whether the image is a positive image or a negative image. In addition, well-known sharpness correction, color enhancement correction, character / illustration input insertion, enlargement /
Processing such as reduction and trimming and special gradation correction processing are also performed if necessary.

As shown in FIG. 3, the image recording unit 12 scans and exposes the yellow, magenta, and cyan photosensitive layers of the silver salt photographic color photosensitive material (color paper) 31 with the light beam 30 to read the negative image. An image of a frame to be printed on the film is recorded on the color photosensitive material 31. Scanning exposure is performed as follows. First, three kinds of light beams 30a, 30b, 30c corresponding to the three photosensitive layers are generated from the beam generators 35a to 35c. This light beam 30a
30 c from the image signal processing unit 11 to the buffer memory 29
Modulation circuit 3 according to the recording control signal sent via
2. Modulation is performed by the modulators 33a, 33b, 33c. Then, these light beams 30a to 30c are combined into one, and the light beam 30 is scanned by the light deflector 37 in the main scanning direction. Further, in synchronization with this, the color photosensitive material 31 is sub-scanned and conveyed by the feed roller pair 34 in the direction (sub-scanning direction) orthogonal to the main scanning direction. The feed roller pair 34 is rotated by a motor 27, and the motor 27 drives the driver 2
It is controlled by the system controller 36 via 8. As a result, the color photosensitive material 31 is two-dimensionally scanned and exposed, and a reproduced image is recorded on the color photosensitive material 31 as a latent image. The exposed color photosensitive material 31 is developed by a well-known paper processor and then cut into individual frames to produce a print photograph. Reference numeral 29 indicates a buffer memory for storing the storage control signal from the image signal processing unit 11, and reference numeral 36 indicates a system controller for controlling each unit. The light deflector 37 includes a collimating optical system 38, a cylinder lens 39, a polygon mirror 40, and a cylinder lens 41. The polygon mirror 40 is rotated by a mirror driving unit 42. Timing control unit 4
3 generates a synchronization signal based on the beam detection signal from the beam sensor 44 and sends it to the modulation circuit 32. The image forming unit 45 is composed of an fθ lens, and narrows the light beam 30 so that the beam diameter will correspond to the pixel to be recorded.

Next, the calculation processing of the digital exposure amount in the image signal processing section 11 will be described. The image signal processing unit 11 performs processing such as sharpness correction, color enhancement correction, character / illustration input insertion, enlargement / reduction, trimming, and the like.
Special gradation correction processing is also performed, but since these are not the gist of the present invention, the functional blocks of these processing units are omitted. As shown in FIG. 1, the image data from the image input unit 10 is written in the image memory 50. The image data written in the image memory 50 is read out and sent to the basic amount calculation unit 51.

The basic amount calculation unit 51 obtains the image recording basic amount Dmi (i is one of R, G and B) based on the image data. The image recording basic amount Dmi is a value obtained from the image density of the original image for each original image, and a simple average value in each area such as the entire screen area, the specific area, and the selected area is selectively used. In addition to this, as the image recording basic amount Dmi, an average value of weighted addition for pixel positions, an average value of selected pixels, an average value of weighted addition, and the like are used. As the image recording basic amount Dmi, one or both of a density control value Dmdi that controls the image density and a color control value Dmci that controls the image color are used.

The density control value (density correction value) Dmdi
Are disclosed in JP-A-51-138435 and JP-A-53-1.
It can be determined using a known method such as those described in JP-A-45621, JP-A-54-28131 and JP-A-59-164547. Further, the color control value (color correction value) Dmci is described in JP-A-55-26569.
JP, JP-A-61-223731, JP-A-2-
It can be determined using a known method such as those described in JP-A-90140, JP-A-3-53235, and JP-A-5-289207. Further, the image recording basic amount Dmi is a weighted average value of the maximum value (or highlight portion density) and the minimum value (or shadow portion density),
An image of the original image such as a weighted average value obtained by multiplying each pixel by weight (for example, a weighted average value obtained by multiplying each class of the density histogram by a weight), a value corresponding to the specific frequency or the selected frequency of the cumulative density histogram The value that characterizes
In particular, a value characterizing the main subject density or a value having a correlation with the main subject density described in JP-A-5-100328 can be used as the image recording basic amount Dmi.

The recorded image information calculation section 52 calculates recorded image information for determining the projected light amount of each pixel. Specifically, the recorded image information E _ij of each pixel is calculated based on the following mathematical formula 1, and this is sent to the data conversion unit 53.

[0026]

## EQU1 ## E _ij = k _i ^S _ij ^{10 Dmi + bi} where S _{ij is the} image signal (photometric value of the original image) i is one of R, G, and B. j: Indicates each pixel number. b _i: the photosensitive material 31, the image input unit 10, an image recording section 12
Factors caused by factors such as, etc., values determined to correct various daily fluctuations 10 ^{Dmi + bi} : One value determined for each original image k _i : A coefficient of 1.0 normally, changed based on image signal S _{ij as} necessary You may. It also has different values depending on whether it is a negative document or a positive document.

The data converting unit 53 obtains the image signal controlled variable F _ij using a conversion table for recording the image information E _ij and the image signal controlled variable F _ij, the image signal control amount F _ij in the image recording section 12 send. The conversion table is created by determining the image signal control amount F _ij from one condition or a plurality of conditions in which the predetermined recorded image information E _ij (= RI) has a predetermined recorded image density. For example, a condition is used such that the predetermined recorded image information value E _ij (= RI) becomes the predetermined recorded image density “0.10”. Therefore, the relationship between the image signal control amount F _ij and the recording image density DRI _ij is obtained from the recording image density DRI _ij obtained by generating the output based on the determined image signal control amount F _ij , and the recording is performed by this. The relationship between the image information E _ij and the image signal control amount F _ij is determined. This relationship may be obtained as a functional expression and calculated by using a look-up table memory (LUT). The relationship between the recorded image information and the image signal control amount is influenced by the spectral characteristics of the photometric sensor of the image input section and the image recording section and the characteristics of the photosensitive material. It is preferable to redefine by FIG. 4 shows the recorded image information E _ij and the image signal control amount F thus obtained.
An example of a conversion table with _ij is shown.

FIG. 5 is a functional block diagram showing another embodiment, which is different from the one shown in FIG. 1 in that a second arithmetic unit 60 is provided, and a second arithmetic unit 60 outputs a arithmetic unit switching signal from a selection signal input unit 61. Accordingly, the first calculation unit 62 including the basic amount calculation unit 51 and the recorded image information calculation unit 52 for image recording of the present invention or the second calculation unit 60 is selected. In FIG. 5, the same components as those in FIG. 1 are designated by the same reference numerals. The second calculation unit 60 is for recording an image based on a known maximum reference value and minimum reference value. Then, switching to the second calculation unit 60 is performed by using a tungsten light, a fluorescent lamp, a shooting scene under a different light source different from daylight such as evening and shade, a shooting scene with a low contrast such as a cloudy sky or a landscape with a lot of haze, and an underexposure. With respect to the film original image, etc., the second arithmetic unit 60 is selected, the image signal is corrected based on the maximum reference value and the minimum reference value, and the image is recorded. This selection may be performed by displaying a simulated image on a monitor such as a CRT and visually confirming the scene. Further, as shown in FIG. 6, automatic selection means 70
It is also possible to estimate the image content from the image signal and automatically select which of the calculation units 60 and 62 is used. For example, when the highlight point of the image and the hue of a large number of pixels in the highlight image portion of the image are close to the artificial light source color, the second calculation unit 60 is selected. Then, the image signal control amount F _ij is determined so that the highlight point or the like becomes white. The switching to the second calculation unit 60 is effective when applied to the case where the original image is a positive image. Note that FIG.
5, the same components as those in FIG. 5 are designated by the same reference numerals.

The second arithmetic unit 60 is, for example, disclosed in Japanese Patent Laid-Open No. 6-2.
As described in Japanese Patent No. 42521, a conversion function for determining a maximum reference value and a minimum reference value in an image signal and matching the maximum reference value and the minimum reference value of each color with a predetermined value after conversion. Then, a conversion table of the image signal control amount for the second calculation unit 60 is created. Then, using this conversion table, the data conversion unit 53 obtains the image signal control amount.

The recorded image information E _ij of each pixel calculated by the recorded image information calculator 52 is a function of one value DM _i determined from the image signal S _ij and the image feature amount of each original image, that is, E _ij.
= F (S _ij , DM _i ) or logE _ij = g (S _ij , D
M _i ). For example, instead of using the above formula 1, the following formulas 2 to 5 may be used.

[0031]

[ _Equation 2] E _ij = K _i · S _ij · DM _i , where K _i : photosensitive material 31, image input unit 10, image recording unit 12
Factors caused by, etc., values determined to correct various daily fluctuations DM _i (= 10 ^Dmi ): One value determined for each original image

[0032]

[ _Equation 3] E _ij = _{EX i} · k _i · (T _ij / T _{0 ij} ), where _{EX i is} the exposure amount for obtaining the proper copy image density T _{ij is} the image signal of each color (amount of transmitted light or reflected light of the original image) T _0ij : Image signal of each color when there is no original image When Equation 3 is logarithmically expressed, Equation 4 is obtained.

[0033]

Equation 4] _{logE ij = logEXi + logk i (} T ij / T 0ij) = (ai · Dmi + bi) -k 'i · D ij However, D _ij: (density value of each pixel of the original image) the image signal of each color k' _i : usually a coefficient of 1.0, image signal D if necessary
_It may be changed _{depending on ij} . Further, the value may be different depending on whether it is a negative document or a positive document. It is also possible to control the three-color gradation balance by selecting an appropriate value. a _i : coefficient (usually 1.0) b _i : constant (determined by copying material and copying machine)

To do this, logE _{ij for} each pixel
Then, E _ij is _calculated from the conversion table.
Further, instead of Dmi, as in Equation 5, D _0i (D _0i
May use a reference image for setting image recording conditions. The above coefficients k _i and k ′ _i are effective for improving the compatibility between the copy material and the original image by selecting the coefficient or the coefficient table based on the film information when the gradation compatibility is poor. . The method of determining all the recorded image information E _ij derived from these mathematical expressions is included in the present invention.

[0035]

[Equation 5] logE _ij = Ai · (Dmi−D _0i ) −k ′ _i ·
D _ij + Bi where Ai, Bi: coefficients

As shown in the equations 4 and 5, the above equations invert the image signal when D _ij is negative. Therefore, if the copying material is made for a negative film, the negative image of the negative film does not require special reversal processing, but if the original image is a positive image, it is reversed to obtain a positive reproduction image. Perform processing.

As the image recording basic amount Dm _i of the original image, in addition to the above, the maximum value (or the density of the highlight portion) described above is used.
Weighted average value of and the minimum value (or shadow density),
A value that characterizes the image of the original image, such as a weighted average value obtained by multiplying each pixel by weight (for each class of the density histogram), a specific frequency of the cumulative density histogram, or a value corresponding to the selected frequency, especially the main subject Characterize the concentration,
Alternatively, there is a value having a correlation.

The image recording basic amount Dm _i of the original image may be a reference value, a value peculiar to the image, or a value obtained from the value. The reference value is obtained from a reference image density, a reference value obtained in advance, or a value specific to the film (for example, an average density value of a large number of original images, a base density of a photographic film, or one image data including an original image). Characteristic value) or a function including them. In particular, one original image may be input and the image signal processing may be performed after this input is completed. In this case, the basic image recording amount Dm _i
In obtaining, the characteristic value obtained from one image data and the characteristic value obtained from a large number of image data can be used in addition to the image data of the original image to be copied.

The image recording basic amount Dm _i of the original image is used as a density control value Dmd _i for controlling the density of the image, for example, Japanese Patent Application Laid-Open No. 52-156624, Japanese Patent Application Laid-Open No. 2-287531, and Japanese Patent Application Laid-Open No. 4-346332. As described in the publication, by extracting a main subject (human face) from a film image and using its density, it is possible to obtain a high-quality print unattended.

Further, a film information input section may be provided, and in this case, the film type is identified by reading the DX code recorded on the photographic film.
Then, it is effective to accumulate the image signal (density value) for each film type and use it to obtain the image recording basic amount Dm _i . Further, instead of the image recording basic amount Dm _i , it is possible to prevent color variation between images by using a weighted average value of Dm _i and the accumulated image signal for each film type. Further, the gray three-color balance value or the three-color balance value of the average image can be found from the accumulated image signal for each film type, and can be used for color control or extracting a specific image.

Further, as described in JP-A-2-278249 and JP-A-3-153229,
Camera information at the time of shooting may be input manually, magnetically, or electrically, and the camera information at the time of shooting may be used for image processing. Further, image processing may be performed by using film manufacturing information or trimming information as described in JP-A-3-120527.

In the above-described embodiment, the LUT or the functional relationship indicating the relationship between the recorded image information and the image signal control amount necessary to obtain the recorded image density is defined, and the image signal control amount is obtained from the recorded image information. Although the image recording method has been described above, in addition to this, the image signal control amount (output) with respect to the image signal (input) is determined from the relationship between the recording image information with respect to the image signal and the relationship between the image signal control amount with respect to the recording image information. A conversion table indicating the relationship may be created for each original image, and the image control amount may be directly obtained for each image signal. This case is also included in the present invention. Also,
The present invention includes all modifications and applications based on the above formulas and the method of the present invention.

When an index print is made from a negative film, the present invention is carried out when a positive image is converted and displayed on a CRT image display device, a reproduced image is confirmed, and an index print is made based on a CRT display signal. You may. In this case, the index print can be created without using the positive image signal from the image display device.

In the above embodiment, the description was made based on the data obtained by picking up the negative image recorded on the photographic film, but in addition to this, the image data picked up by the electronic still camera, recording of reversal film, reflection original, CD, etc. You may use the positive image signal read from the medium.

The image recording section may be constituted by an exposure means for controlling a large number of pixels spread on the surface such as a liquid crystal or a CRT, in addition to the one using a light beam. Also,
The copying material is not limited to the color light-sensitive material,
For example, a thermal printing method using a thermosensitive recording material, a sublimation type or a heat melting type ink ribbon, an inkjet printing method, a toner transfer printing method, or the like may be used.

In the above embodiment, the image input unit 10, the image signal processing unit 11, and the image recording unit 12 are integrated into one unit. However, these are the image input unit 10, the image signal processing unit 11, and the image recording unit. It may be separated from the part 12. Also,
In the above-described embodiment, the image recording unit 12 is used to record an image on a recording medium such as a color photosensitive material 31, a heat-sensitive recording material, or plain paper to create a hard copy. However, instead of the image recording unit 12, the image is recorded. The present invention may be applied to the case where the display unit is used to simply reproduce a soft copy for displaying an image on a display such as a CRT or a liquid crystal display panel.

[0047]

As described above, the present invention provides a method for digitally processing image data to correct gradations and gradation balances based on highlight points and shadow points or cumulative histograms. Image editing, insertion of characters and illustrations, sharpness correction, color tone correction, etc. are applied to the exposure control method of the surface exposure method, so that the characteristics of digital image processing and the characteristics of the surface exposure method in photographic printing can be obtained. Therefore, it is possible to obtain stable and high reproduced image quality with less variation between prints as compared with the conventional image recording method by digital processing.

Further, in the conventional method of copying by digital processing, since reproduction of highlights and shadows of the original image was emphasized, there was a problem in reproduction of colors and densities of the main image portion. In the invention, the reproduction condition can be determined based on the information related to the main subject and the extraction result of the main subject (face), and the color and density of the main image portion are excellent in reproduction.

Furthermore, by selectively using a method that emphasizes highlight and shadow image recording and a method that emphasizes reproduction of colors and densities of the main image portion depending on the scene, even in conventional digital exposure. It is possible to obtain a high-accuracy, high-quality reproduced image that could not be achieved even by surface exposure.

Furthermore, in the conventional digital processing method, since the reproduction of highlights and shadows of the original image is emphasized, an image with unnatural gradation reproduction is also generated. However, in the present invention, by selectively using it, It is possible to obtain a high-accuracy, high-quality reproduced image that cannot be achieved by conventional digital exposure or surface exposure.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing the gist of a digital image recording apparatus of the present invention.

FIG. 2 is a schematic diagram of an image input unit.

FIG. 3 is a schematic diagram of an image recording unit.

FIG. 4 is a diagram showing an example of a data conversion table in a data conversion unit.

FIG. 5 is a functional block diagram showing another embodiment.

FIG. 6 is a functional block diagram showing another embodiment.

[Explanation of symbols]

 10 image input unit 11 image signal processing unit 12 image recording unit 13 film information input unit 14 manual information input unit 20 negative film 24 line sensor 25 signal processing circuit 30, 30a, 30b, 30c light beam 31 color photosensitive material (color paper) 33a, 33b, 33c modulator 35a, 35b, 35c beam generator 50 image memory 51 basic amount calculation unit 52 recorded image information calculation unit 53 data conversion unit 60 second calculation unit 61 selection signal input unit 62 first calculation unit 70 Automatic selection means

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location 9061-5H G06F 15/70 460E

Claims (7)

[Claims] 1. A digital image recording method for recording a reproduced image composed of a positive image based on an image signal of an original image composed of a negative image or a positive image, which is common to each image signal according to an image feature amount obtained from the image signal. A digital image recording method characterized in that an image recording basic amount used for is determined, an image signal control amount for each image signal is determined from the image recording basic amount and each image signal, and an image is recorded. 2. A digital image recording method for recording a reproduced image composed of a positive image based on an image signal of an original image composed of a negative image or a positive image, which is common to each image signal according to an image feature amount obtained from the image signal. The image recording basic amount used for the recording is calculated, and the recording image information for each pixel for recording an image is calculated from the image recording basic amount and each image signal, and the recording image information and the recording image density for this recording image information are obtained in advance LU showing the relationship with the required image signal control amount
A digital image recording method characterized in that T or a functional relationship is defined, and an image is recorded by obtaining an image signal control amount from the recorded image information based on the relationship. 3. A reproduced image consisting of a positive image is highlighted by an image signal of an original image consisting of a negative image or a positive image,
In a digital image recording method of obtaining an image signal control amount to be recorded based on a shadow point and recording an image using this image signal control amount, an original image is obtained based on an image feature amount obtained from the image signal by a selection signal of the image recording method. The image recording basic amount commonly used for each image signal for recording is obtained, the recording image information for each pixel for recording an image is obtained from the image recording basic amount and each image signal, and the recording image information is stored in advance. LU showing the relationship between the recorded image information and the image signal control amount necessary to obtain the recorded image density
An image using the image signal control amount based on the highlight point and the shadow point according to the scene of the original image, by defining T or a functional relation, and obtaining the image signal control amount from the recorded image information based on the relation. A digital image recording method, characterized in that a recording method and an image recording method using an image signal control amount based on the recorded image information are selected and used. 4. The digital image recording method according to claim 1, wherein the image feature amount is an average value of image signals of all image portions or partial image portions, or an average of selected image signals. A digital image recording method, comprising at least a value, wherein the image recording basic amount comprises a density control value for controlling an image density and a color control value for controlling a color. 5. A digital image processing apparatus for processing a digital image signal to record a reproduced image composed of a positive image based on an image signal of an original image composed of a negative image or a positive image, wherein image characteristics obtained from the image signal Image recording basic amount calculating means for obtaining an image recording basic amount commonly used for each image signal according to the amount, and recording image information calculating means for calculating recording image information for each pixel from the image recording basic amount and each image signal An LU indicating the relationship between the print image information and the image signal control amount necessary to obtain the print image density for the print image information in advance.
An image signal control amount conversion means for determining an image signal control amount from the recorded image information on the basis of T or a functional relation, and the digital image processing device. 6. A digital image processing apparatus for processing a digital image signal to record a reproduced image composed of a positive image based on an image signal of an original image composed of a negative image or a positive image, wherein image characteristics obtained from the image signal A first image signal control amount calculation means for calculating an image recording basic amount commonly used for each image signal according to the amount, and calculating an image signal control amount for image recording from the image recording basic amount and each image signal. A second image signal control amount calculation means for calculating an image signal control amount for image recording from the image signal using an image recording table connecting the highlight image reference point and the shadow image reference point; Alternatively, the digital image processing apparatus is provided with a selection unit that selects the second image signal control amount calculation unit. 7. A digital image recording apparatus for recording a reproduced image composed of a positive image based on an image signal of an original image composed of a negative image or a positive image, in which each image signal is commonly used by an image feature amount obtained from the image signal. First image signal control amount calculation means for calculating an image recording basic amount to be used, and calculating an image signal control amount for image recording from the image recording basic amount and each image signal, a highlight image reference point and a shadow Second image signal control amount calculation means for calculating an image signal control amount for image recording from the image signal using an image recording table connecting image reference points, and first or second image signal control amount calculation A selection means for selecting the means, and an image recording section for recording an image according to the image signal control amount from the image signal control amount calculation means selected by the selection means. Digital image recording device.