JPH0792568A - Method for processing photographic picture information - Google Patents

Abstract

PURPOSE:To accurately and stably give appropriate copying conditions considering the visual characteristic of a human being for an individual original picture by combining plural film characteristic value vectors and obtaining exposure vetcor for forming the copied image of the original picture. CONSTITUTION:The original picture formed on color photographic film is scanned color-separating to obtain image information classified by colors (S3), and an image characteristic value such as a mean value is obtained from the image information (S4). Furthermore, plural reference values for referring to a film characteristic function are obtained from the image characteristic value (S5). Then, the film characteristic value is obtained based on the reference values by referring to the film characteristic function (S7) so as to constitute plural film characteristic value vectors (S8). Next, the exposure vector is obtained from the characteristic vectors (S9). When the copied image of the color original picture is formed based on the obtained exposure vector, the color tone of the obtained copied image is observed as a fixed color tone regardless of the characteristic of the photographic film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing method for producing a color copy image from an original image formed on a color photographic film by using an electrophotographic copying machine, a laser printer, a photographic printing apparatus or the like. Relates to a photographic image information processing method for determining an exposure amount for producing a copy image of the original image based on the characteristics of a color photographic film.

[0002]

2. Description of the Related Art In general photography, the subject's blue (B), green (G), red (R) (hereinafter simply referred to as B,
It is known as an empirical rule that the average reflectances of the three primary colors (described as G and R) are substantially constant. Therefore, in the conventional photo printing apparatus, the total area average transmission density (LAT
D) is measured, and the exposure amount in photographic printing is determined based on the measured average transmission density, whereby the exposure amount given to the B, G, and R photosensitive layers of the photographic paper is controlled to be constant,
A photographic print with good color balance is created (usually called "LATD control").

When a film of a standard subject is taken as an object, such an exposure amount control method is used to maintain a constant value of the exposure amount given to the B, G, and R color photosensitive layers of the photographic paper, thereby maintaining the color balance. A good photographic print can be created.

However, in the case of a subject having an inherent bias in luminance distribution and color distribution (called subject ferria), it is difficult to obtain a proper photographic print by the above-mentioned LATD control method. Among these subject ferria, those caused by the unevenness of the luminance distribution of the subject are called density ferria, and those caused by the uneven color distribution are called color ferria. As a known technique for the purpose of density correction for automatically adjusting the exposure amount with respect to the density ferria, the following technique disclosed in Japanese Patent Publication No. 56-2691 can be cited. That is, the original image on the photographic film is scanned, the characteristic value is obtained for each area of the image from the image density obtained by this scanning, and the classification is performed based on this characteristic value. The function adjusts the exposure amount for the original image.

Further, as a technique aiming at color correction for automatically adjusting the exposure amount for a color ferria,
The lowward collection is known. This gives a relatively low exposure amount to a relatively high negative density component based on a comparison with a standard LATD (usually a standard original LATD).

Generally, in a photo-printing apparatus of the LATD control system, changes in the densities of B, G, and R colors of an original image are caused by the difference between the characteristics of the photographic film and the color distribution of the subject. Can not be identified automatically. For this reason, various exposure conditions such as the reference density for color correction as described above are preset for each type of photographic film, and the set reference exposure conditions are selected according to the type of photographic film to be printed. ing. However, this setting of the standard exposure conditions requires a great deal of labor because trial and error of trial exposure and inspection of the photographic prints obtained by it are repeated, and it is an important factor that influences the quality of all photographic prints. Since it is a process, it requires skill and high skill.

On the other hand, in recent years, high-sensitivity films, films according to applications, or new films with various improvements have been released from various manufacturers, and the number of film types has increased greatly.
There are dozens of different types. Therefore, there is a demand for a method capable of giving appropriate exposure conditions to individual original images from one reference exposure condition regardless of the characteristics of each type of photographic film. In response to such a demand, the following method has been proposed in which the exposure amount is determined based on the measurement value belonging to a predetermined chromaticity region.

In Japanese Patent Application Laid-Open No. 51-94927, the density of three primary colors of a color photographic original is selected from the points of low saturation by comparison with the density of a standard original, and the three primary colors of the selected points are selected. A method of determining the exposure amount based on the density of is shown. However, this method uses one standard original image as the comparison standard for saturation.The selected saturation is not necessarily the same for each photographic film because the characteristics of the photographic film differ depending on the product type and storage condition. The result is that the resulting photographic prints are different depending on the characteristics of the photographic film.

In Japanese Unexamined Patent Publication No. 52-156624, a point included in a predetermined color solid is determined as a flesh color based on the densities of the three primary colors of a large number of points in a color original image, and this flesh color has a predetermined color in a color print. The method of performing color correction so as to be reproduced in FIG. However, the characteristics of photographic film generally differ greatly depending on the product type and storage condition, and even if the same skin-colored subject is shot under the same shooting conditions, the density recorded on each photographic film will be different. There is no guarantee that it will be constant. Therefore, this method has a drawback that the result varies depending on the type and storage condition of the photographic film, and when the number of measurement points included in the skin color region is small, it is easily affected by noise included in the image data, It has the drawback of lacking reproducibility. Moreover,
The assumption that a subject includes a person is not always realistic.

In Japanese Patent Laid-Open No. 59-220760, the lowest density point (including mask density) in the original image of a photographic film or its periphery is determined, and the chromaticity of each measurement point is determined based on this density. A method is shown in which the limit value of chromaticity is expanded with an increase in the neutral density of each measurement point, and a measurement point that does not exceed this limit value is selected.

Further, Japanese Patent Laid-Open No. 3-46648 discloses that
Based on the average value of the photometric data belonging to the area selected according to the chromaticity of the standardized data after correcting the photometric data of the three primary colors of many points of the color original image with the low-density area photometric data A method for determining the exposure dose is shown.

These proposals assume that the mask density or the density in the vicinity thereof is the main characteristic difference of the photographic film, and that the characteristics in other density regions are approximate. However, it is widely known that the tone reproduction characteristics of color photographic films differ from product to product, as indicated by the characteristic curve, and the preconditions for the above method are not always appropriate. Therefore, although the selected chromaticity is constant in the vicinity of the mask density, it is different for each photographic film in other density regions, and as a result, the obtained photographic print is different depending on the characteristics of the photographic film. Has not been resolved. In addition, this method also has a new drawback of requiring extremely complicated arithmetic processing.

[0013]

As described above, in the method of determining the exposure amount based on the measured value belonging to the predetermined chromaticity area, the chromaticity determination result is the photographic film type, storage state, etc. Affected by the characteristics of the photographic film due to photographic film.-It is not possible to identify if the subject does not include a person, especially the skin-colored part.-The accuracy and reproducibility are poor because it is easily affected by the noise contained in the measured values. There were problems such as the inability to adapt to human visual characteristics, which tend to focus on the highlight areas of prints.

The present invention has been made in view of the above points, and it is possible to obtain a copy image having a constant color tone regardless of the characteristics of each type of color photographic film and the developing / storing conditions. It is an object of the present invention to provide a color image information processing method capable of stably giving an appropriate copying condition to an original image in consideration of human visual characteristics with high accuracy.

[0015]

In order to achieve the above-mentioned object, a photographic image information processing method of the present invention is a color image scanning of an original image formed on a color photographic film, and an image of the original image is obtained from the obtained image information. A characteristic value is obtained, a preset film characteristic function is referred to by the image characteristic value to calculate a plurality of film characteristic value vectors, and a copy image of the original image is created by combining the plurality of film characteristic value vectors. The exposure amount vector for is calculated.

Further, the film characteristic function is derived from image information of a plurality of original images. Further, the plurality of original images are those in the same film. Also, the plurality of original images are to be spread over a plurality of films. Further, the plurality of films belong to the same group among the groups determined in advance for each product type.

[0017]

[Function] The original image formed on the color photographic film is color-separated and scanned for each color (i: color type, i = 1, 2, ... I)
Image information is obtained, and an image characteristic value such as an average value is obtained from this image information. Further, a plurality of reference values P _m (m: reference value code, m = 1, 2, ... M) for referring to the film characteristic function are obtained from the image characteristic values.

Next, the film characteristic value T _im is obtained by referring to the film characteristic function with these reference values, and thereby a plurality of film characteristic value vectors T _m are constructed. T _m = (T _1m , T _2m , ..., _Tim ) Next, the exposure amount vector E is obtained from these film characteristic vectors T _m . E = E ₀ + α ₁ T ₁ + α ₂ T ₂ + ... + α _m T _m When combining the film characteristic value vectors T _m , human visual characteristics are taken into consideration, and for example, high weighting is applied to the highlight side of the image. To give. When a copy image of the color original image is created based on the exposure amount vector E thus obtained, the color tone of the obtained copy image is observed as a constant color tone regardless of the characteristics of the photographic film.

The film characteristic function used when constructing the film characteristic value vector is provided by a manufacturer in a predetermined format, an original image in the same film, an original image over a plurality of films, or predetermined for each product type. It can be obtained by accumulating image information of a plurality of original images by an appropriate method for original images belonging to the same group among the created groups.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the photographic image information processing method of the present invention will be described below with reference to the drawings. Although the present invention can be applied to a color copying machine or the like, the case of being applied to a photo printing apparatus will be described here as an example.

(Regarding the structure of the photographic film) FIG.
1 shows the structure of a 135 photographic film that has been subjected to development processing. In the figure, a photographic film F, which has been subjected to development to form an original image (group) I, is spliced by a splice portion S and is formed into a roll shape by being joined together. The rolled photographic film F has a notch (group) showing the center position of the original image in the notch step before the photographic printing step.
N is located on its side edge. By detecting the notch N, conveyance control such as positioning of the photographic film F in the subsequent steps is performed. As shown in the figure, the photographic film F is provided with an identification code (for example, DX code) D indicating its type. Further, a well-known perforation (group) P is arranged in advance on this side edge portion. The photographic film F in this example is not limited to the 135 photographic film, but other photographic films (for example, 11
Of course, it may be 0 film). Roll-shaped photographic film F processed in this way
Is subjected to printing processing in a photo printing apparatus.

(Structure of Photographic Printing Apparatus) In FIG. 3 showing the structure of the photographic printing apparatus, the photographic film F is set on the spool 1, and the spool 2 is passed through a predetermined conveying path.
To be wound up. A scanning unit 3 is provided in the middle of the path, whereby the original image recorded on the photographic film F is separated into B, G, and R colors and scanned.

The scanning unit 3 is provided with a well-known one-dimensional CCD for performing main scanning in the width direction of the photographic film F for each color, and color separation scanning is performed by these and obtained B, G, and The image signal of each R color is supplied to the image processing unit 5. Further, the notch N, the splice portion S, and the identification code D provided on the photographic film F are detected by a detector (not shown), and the detection signal is supplied to the transport control unit 4. The transport control unit 4 processes the detection signal and sends it as a notch signal, a splice signal, and an identification code signal to the image processing unit 5 and the information processing unit 6 via the system bus 7, and drives a pulse motor to drive the photographic film. Control the transport of F. Further, the carrier pulse at this time is supplied to the image processing section 5 as a synchronizing signal at the time of sampling of the image signal, and the sub-scanning is performed accordingly.

In the image processing section 5, the image signal supplied from the scanning section 3 is amplified, sampled and held, and the A / D
To be converted. Further, the image processing unit 5 includes a CCD of the scanning unit 3.
There is provided a timing control circuit (not shown) which sends out a drive signal for driving, and controls the sampling timing. The A / D-converted image signal is converted into a density value via a LUT (look-up table) composed of a ROM or the like, and is further shaped by appropriate rounding processing in both the main scanning direction and the sub-scanning direction. However, in the end, regardless of the format of the photographic film F, a predetermined number of pixels, here, for example, 16 × 16
Two-dimensional image density information (hereinafter, simply image information) made up of pixels is obtained, and this information is sent to the information processing unit 26.
The B, G, and R color image signals thus obtained in the scanning unit 3 are sent to the image processing unit 5, A / D converted and shaped into image information in a predetermined format, and then the information processing unit 6 Sent to. Therefore, the information processing section 6 can perform common processing regardless of the format of the photographic film F.

The image information is subjected to a series of information processing, which will be described later, in the information processing section 6, and as a result, the exposure amount for each original image is calculated, and the signal of this exposure amount is exposure controlled through the communication line 8. It is transmitted to the section 9. The photographic film F that has passed through the scanning unit 3 is provided between the scanning unit 3 and the exposure unit 22 in order to absorb the difference in the transport speeds of the photographic films F and simultaneously to scan a plurality of original images prior to exposure. The data is sent to the exposure unit 22 through the buffer unit 10. Note that the transport path between the scanning unit 3 and the exposure unit 22 has a length corresponding to a maximum of 24 sheets of 135 photographic film, and as a result, almost all of the images recorded on one 24 sheets of 135 photographic film are recorded. The image information corresponding to the original image I can be obtained prior to exposure.

Each original image formed on the photographic film F is positioned in the exposure section 22, and the light emitted from the light source 20 is illuminated by the diffusion section 21 as uniformized light.
Further, the lens 24 optically forms an image on the photographic printing paper 40 to expose it. Here, the exposure amount is the exposure control unit 9
In, the yellow (Y), magenta (M), and cyan (C) filters 20 arranged above the exposure unit 22
a, 20b, 20c and the driving condition of the shutter 52 arranged below the exposure unit 22 are converted. The filters 20a, 20b, 20c and the shutter 23 are inserted in the exposure optical path according to the driving conditions, and the exposure given to the photosensitive layers of the respective colors of the photographic printing paper 25 is adjusted. After completion of this exposure, the photographic printing paper 25 is transported by a predetermined distance in preparation for the next exposure, and the photographic film F is transported to position the original image I to be printed next in the exposure section 22.

(Regarding Configuration of Information Processing Unit) In the detailed configuration diagram of the information processing unit in FIG. 4, image information D _i (X, Y) of each color of B, G, R sent from the image processing unit 5
(I: B, G, R, and so on) is stored in the memory 102 via the system bus 7. The CPU 104 reads out the image information stored in the memory 102 and calculates the exposure amount for each original image I formed on the photographic film F.

This exposure amount is transmitted to the exposure controller 9 through the communication line 8
Sent through. Further, the transport control circuit 4 of the scanning unit 3
The notch signal, the splice signal, and the identification code signal sent from the system via the system bus 7 are also stored in the memory 102.
And is processed by the CPU 104.

The auxiliary storage unit 106 stores information to be saved, constants necessary for processing, and the like. The auxiliary storage unit 106
Is composed of, for example, a magnetic disk, and the recording information can be taken out to the outside as needed.
This not only allows you to store information for a long time,
The information can be saved even when the power is cut off, the information saved by an external independent device can be processed, and constants and the like can be initialized and changed. Long-term accumulated information, which will be described later, is stored in the auxiliary storage unit 106 and loaded into the memory 102 as needed. Further, 108 is a keyboard for various operations, and 112 is a display, which can be input and output through the interface circuit 110.

(Regarding internal processing in the information processing section)
Hereinafter, the image information processing in the information processing unit 6 will be described in detail. The statistical amount of image information obtained from a plurality of original images recorded on a photographic film is effective as information indicating the characteristics of this film. In this embodiment, the case where the cumulative density function CDF _i (D) is used as such a statistic will be described. The cumulative density function CDF _i (D) is the frequency F of the image information.
From RQ _i (D), it is obtained by the following equation (1).

[0031]

Note that this cumulative density function can be simply added, and if it is added for each film type group over a plurality of original images according to the following equation (2), the accumulated information ACDF _ij
Is obtained. Here, ACDF _ij.-1 (D) indicates the accumulated information in advance, j indicates the film type group, and so on. ACDF _ij (D) = CDF _i (D) + ACDF _ij.-1 (D) (2)

In this way, the cumulative density function is obtained from a plurality of original images recorded on the photographic film, and the cumulative density function ACDF _ij (D) has a close correlation with the tone reproduction characteristic of the photographic film. It has been confirmed by experiments. Therefore, in this embodiment, an example in which this cumulative density function is used as a film characteristic function will be described.

The film characteristic functions include: short-term storage information obtained for each film; long-term storage information obtained for a plurality of films of the same product type or product group; films of the same product type or product group. It is conceivable that the information is based on characteristic information in a predetermined format defined by the manufacturer, but here, the processing when long-term accumulated information is used will be described.

FIG. 1 is a flow chart showing an example of the flow of processing according to the present invention. In step S1, the type (group) of the target film is determined from the identification code signal sent from the transport control unit 4. FIG. 5 shows an example of the correspondence relationship between the identification code and the product group.
As shown in the table, a product type group is individually assigned to each identification code, but this product type group may be common to the identification codes. by this,
It is possible to limit the type group to a fixed number and adjust the storage amount of long-term accumulated information according to the data storage area.

If the identification code is unreadable or the product group corresponding to the read identification code cannot be determined, a predetermined product group is automatically set. The default shown in FIG. 5 corresponds to such a case. As shown in this table, a method of assigning an exceptional product group (corresponding to 0 of default (1) in FIG. 5) to the default, and a standard product group (1 of default (2) in FIG. 5) There is a method of assigning). As a result, it is possible to automatically cope with an exceptional situation in which the identification code cannot be read or the product type group corresponding to the read identification code cannot be determined. However, it goes without saying that in such a case, an alarm or the like may be issued to artificially specify the identification code or the product type group.

When the product type group is determined, step S
In 2, the long-term storage information ACDF corresponding to this product type group is loaded from the auxiliary storage unit 106 into the memory 102. Note that the representative value for each product type group is stored in advance in the auxiliary storage unit 106 as the initial value of the long-term storage information ACDF, and the long-term storage information in which a sufficient number of films have been stored even in the initial stage of the processing related to the product type group. It is considered that the effect is almost the same as that of using.

Further, in step S3, the scanning unit 3
In the memory 102, the image information that has been color-separated and scanned, is shaped by the image processing unit 5, and is sent to the information processing unit 6 is stored. Based on this image information, the average value AVE _G of the image information of green (G) is calculated as the image characteristic value in step S4. Needless to say, the color is not limited to green and may be another color. Further, instead of the average value, a statistical value of image information such as a median value may be used as the image characteristic value.

In step S5, a reference value P _m (m: reference value code, m =
1, 2, ... M) are calculated by calculation based on the image characteristic values. The image characteristic value is a reference reference value P _N (N: reference reference code, 1
<N <M). Reference value P _m is green (G)
It is assumed that the image information is obtained according to the following equation (3), but the color and the calculation method are not limited to this. P _m = AVE _G + (m−N) Δ (Δ> 0) P _N = AVE _G (3)

Thus, by obtaining the reference value based on the image characteristic value, it becomes possible to refer to the film characteristic function according to the characteristic of the original image such as the photographic exposure and the tone reproduction of the photographic film in the reproduction range used. The exposure amount can be determined in consideration of the characteristics. A constant may be used as the value of Δ, but for example, the standard deviation S of green (G) image information is
TD _G may be adopted. Further, a value obtained by equally dividing the section of the average value, the minimum value, and the maximum value of the image information may be adopted. Alternatively, the image information may be divided into areas such as a highlight area and a shadow area, and the characteristic value of each area may be used as a reference value.
In this way, by closely associating the reference value with the image information, it becomes possible to refer to the film characteristic function according to the image characteristics such as the range of reproduction range to be used, contrast, and density distribution. The exposure amount can be determined by associating the visual characteristics of the.

Next, the film characteristic function (long-term accumulated information) is referred to by these reference values, and the film characteristic value is obtained as follows. First, in step S6, the cumulative density function values Q _m and Q _N corresponding to the reference value P _m and the standard reference value P _N are obtained according to the following equation (4). Q _m = ACDF _G (P _m ) Q _N = ACDF _G (P _N ) (4) A schematic diagram of the method of referring to this cumulative density function (film characteristic function) is shown in FIG. 6.

Further, in step S7, the cumulative density function values Q _m and Q _N are referred to in the equation (5) in the opposite direction, and the film characteristic values T _im and T _iN are obtained for all the reference values and colors, and the equation (5 6) film characteristic value vectors T _m and T _N
Make up. T _im = ACDF _i ^-1 (Q _m ) T _iN = ACDF _i ^-1 (Q _N ) ... (5) T _m = (T _Bm , T _Gm , T _Rm ) _TN = (T _BN , T _GN) , T _RN ) (6)

FIG. 7 shows the cumulative density function (film characteristic function).
3 schematically shows a method of obtaining a film characteristic value vector from As is clear from the equation (1) and FIG. 7,
Since the cumulative density function is continuous at any point and is a monotonically increasing function, the inverse function as described above has an advantage that it can be obtained extremely easily and no exception processing is required. By thus referencing the film characteristic function with a plurality of reference values, it is possible to obtain a plurality of sets of film characteristic value vectors reflecting the tone reproduction characteristics of the photographic film.

In step S8, the film characteristic value vector T _m thus obtained is normalized by the film characteristic value vector corresponding to the standard reference value according to the equation (7), and further the density adjustment value according to the equation (8). Reconstruct K _m and color adjustment vector C _m . By doing so, it becomes possible to adjust the color and the density independently without affecting each other. Note that in equation (8),
U is a unit constant vector of (1, 1, 1). _{T 'm = T m -T N} ··· (7) K m = (T' Bm + T 'Gm + T' Rm) / 3 C m = T 'm -K m U ··· (8) In this way Since the adjustment factor of the exposure amount due to the characteristics of the film is obtained based on the film characteristic function, the exposure amount can be determined with high accuracy.

Next, in step S8, the color adjustment vector C _m and the density adjustment value K obtained from the film characteristic vector T _m.
The exposure amount vector E is obtained by combining _{m according} to the equation (9). In the description below, the symbols are defined as follows. E: exposure vectors (E _B,
E _G , E _R ) E ₀ : reference exposure amount vector (E _0B ,
E _0G, E _0R) A: average density value vector of the original (A _B,
A _G , A _R ) A ₀ : Average density value vector of the reference original image (A _0B ,
A _0G , A _0R ) U: Unit constant vector (1, 1,
1) α _m , β _m : Weighting coefficient γ: Constant

The fourth to sixth terms on the right side of the equation (9) realize the conventional exposure control based on the average transmission density over the entire area, whereby a photographic film having a specific tone reproduction characteristic is obtained. If the used tone reproduction range is within a certain range, a copy image having a substantially constant density and color tone which is not affected by the density change of the original image can be obtained.

On the other hand, since the first to third terms on the right side of the equation (9) are obtained from the film characteristic vector referred to by the image characteristic value, the tone reproduction characteristic of the photographic film is determined by the product type and the developing condition. The exposure amount is adjusted according to the tone reproduction characteristics of each photographic film even when the tone reproduction range used varies greatly depending on the shooting exposure. Can be significantly suppressed.

In the first term on the right side of the equation (9), the color adjustment vector C _m obtained from the film characteristic vector is linearly combined. Here, the weighting coefficient α _m by which each vector is multiplied is set to a larger value on the highlight side. This is in consideration of the human visual characteristic that the difference in color tone is more sensitively recognized in the highlight portion of the observed image. By determining the exposure amount in this way, the color tone of the highlight portion in the copied image can be made constant regardless of the tone reproduction characteristics of the photographic film. As a result, the color tone of the copied image obtained from the original image of the same subject is observed to be constant regardless of the tone reproduction characteristics of the photographic film. In the conventional method of determining the exposure amount based on the average transmission density over the entire area or the image density in a specific chromaticity region, there is a problem that the color tone of the obtained copy image is observed as largely different depending on the characteristics of the photographic film and the exposure of the photograph. However, the method according to the present invention solves this problem.

In the second to third terms on the right side of the equation (9), the density adjustment values K _m obtained from the film characteristic vector are linearly combined and normalized by a constant. As a result, adjustment relating to the reproduction of neutral density is performed according to the tone reproduction characteristics of the photographic film. As a result, in a general original image in which the main subject is in the highlight part, for example, in a photographic film with high contrast, the density of the main subject is reproduced lightly, and in the case of soft tone, the density of the main subject is reproduced densely. The problem of is solved.

Since the film characteristic function is formed on the basis of the statistical amount of a large amount of image information, it is not affected by the noise included in the image information, and a plurality of reference values are used. Since the exposure amount is obtained by combining the film characteristic value vectors of, the exposure amount can be determined with high stability by this method. If the exposure of the original color photographic image is controlled on the basis of the exposure amount vector E obtained as described above, a high-quality copy image suitable for the characteristics of the photographic film and the human visual characteristics can be accurately and stably produced. can do.

In step S9, the exposure amount vector E thus obtained is transmitted to the exposure control unit 9 and converted into shutter and filter driving conditions by a predetermined method, and the shutter and filter are controlled by this result. Then, each original picture is printed on photographic paper.

In step S10, it is determined whether or not the processing for all the original images to be exposed on the film is completed, and if not completed, the exposure amount for each image on the film is sequentially determined. There is. Step S1
In step 1, it is judged whether or not the exposure processing of all the films to be processed is completed, and the above film processing is repeated for the next film.

In the above, this embodiment has explained the case where the long-term accumulated information is used as the film characteristic function. In this way, by using the long-term accumulated information, it is possible to determine the exposure amount corresponding to the film characteristics that differ depending on the type of film and the developing conditions. It is also possible to use film-specific information provided by the manufacturer as a film characteristic function instead of long-term accumulated information. In this case, it is possible to determine the exposure amount corresponding to the film characteristics that differ depending on the type of film.

On the other hand, it is also possible to use short-term accumulated information of image information obtained by scanning a plurality of original images on the same film in advance, instead of long-term accumulated information. In this case, it is possible to determine the exposure amount corresponding to each film characteristic which differs depending on the storage conditions. Further, the long-term accumulated information and the short-term accumulated information may be combined to form new accumulated information. In this case, it is possible to determine the exposure amount comprehensively corresponding to the film characteristics that differ depending on the product type and the developing conditions, and the film characteristics that differ from film to film depending on the storage conditions.

[0055]

As described above, according to the photographic image information processing method of the present invention, the adjustment factor of the exposure amount due to the characteristics of the film is determined based on the film characteristic function and in consideration of human visual characteristics. Therefore, even when the tone reproduction characteristics of the photographic film differ depending on the type and development conditions, it is possible to determine the exposure amount with high accuracy, and it is possible to obtain a copy image with a constant color tone.

Further, since the film characteristic function is obtained by referring to the image characteristic value of each original image, even if the tone reproduction range used for each original image is largely different due to the photographing exposure or the like, a constant color tone is obtained. A duplicate image can be obtained.

In addition, since the film characteristic function and the image characteristic value are given by the statistical amount of the image information, they are not affected by the noise contained in the image information, and a plurality of film characteristic value vectors are combined for exposure. Since the amount is required, the exposure amount can be determined with high stability.

As a result, it is possible to stably give proper copying conditions to each individual original image with high accuracy in consideration of human visual characteristics, and it is possible to provide various kinds of photographic film, developing / storing conditions, and photographing exposure. The present invention has an excellent effect that a copied image having a constant color tone can be obtained regardless of the color tone.

[Brief description of drawings]

FIG. 1 is a flowchart showing a method of the present invention.

FIG. 2 is an explanatory view showing the structure of a photographic film.

FIG. 3 is a configuration diagram of a photographic printing apparatus suitable for using the method of the present invention.

FIG. 4 is a block diagram showing a configuration of an information processing unit of the photo printing apparatus.

FIG. 5 is a diagram showing a correspondence relationship between identification codes and product groups.

FIG. 6 is a principle explanatory diagram showing a method of referring to a film characteristic function.

FIG. 7 is a principle explanatory view showing a method for obtaining a film characteristic value vector.

[Explanation of symbols]

 3 Scanning Section 5 Image Processing Section 6 Information Processing Section 9 Exposure Control Section 22 Exposure Section 104 CPU 102 Memory 110 Interface Circuit F Photographic Film I Original Image

Claims (5)

[Claims] 1. An original image formed on a color photographic film is color-separated and scanned, an image characteristic value of the original image is obtained from the obtained image information, and a plurality of preset film characteristic functions are referred to by the image characteristic value. Of the film characteristic value vector, and the exposure amount vector for creating the copied image of the original image is obtained by combining the plurality of film characteristic value vectors. 2. The photographic image information processing method according to claim 1, wherein the film characteristic function is derived from image information of a plurality of original images. 3. The photographic image information processing method according to claim 2, wherein the plurality of original images are in the same film. 4. The photographic image information processing method according to claim 2, wherein the plurality of original images are spread over a plurality of films. 5. The photographic image information processing method according to claim 4, wherein the plurality of films belong to the same group among groups predetermined for each product type.