JP2000125084A - Document reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain data of high gradations which precisely represent the contents of a document irrelevantly to the contents of the document. SOLUTION: A three-line color CCD 116 which reads a photographic film outputs read signals of R, G, and B in parallel. The read signal of B which is small in the quantity of light made incident on the line CCD 116 is shifted in level by a level adjustment part 92B, then inputted to amplifiers 97A and 97B respectively and amplified with mutually different gains (gain of 97A < gain of 97B), and converted by A/D converters 98A and 98B into digital data, which are inputted to a selector 99. When the gray level of a film image to be read is less than a given value, the data from the A/D converter 98A corresponding to the read signal amplified with the low gain are selected and when not less than a given value, the data from the A/D converter 98B corresponding to the read signal amplified with the high gain are selected and outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading apparatus, and more particularly to an apparatus for amplifying a reading signal output from a reading sensor according to the amount of incident light from a document and performing A / D conversion to digital reading data. And a document reading device that outputs the document.

[0002]

2. Description of the Related Art Heretofore, a photographic film set on a film carrier has been irradiated with light emitted from a light source, and the light transmitted through the photographic film is made incident on a reading sensor such as a CCD sensor and output from the reading sensor. A film reading device that obtains image data of a film image by performing A / D conversion (analog-to-digital conversion) by amplifying a reading signal (a signal having a level corresponding to the amount of light transmitted through the photographic film); 2. Description of the Related Art There is known an image processing system that performs image processing such as various corrections on image data of a film image and records an image on a recording material based on the image data after the image processing. This image processing system has a feature that the image quality of a recorded image can be freely controlled by image processing on image data, as compared with a conventional photographic processing system that records a film image on photographic paper by surface exposure. .

[0003]

By the way, with respect to film images recorded on photographic film, not all film images are recorded under appropriate photographing conditions, and the transmission density may vary greatly. Many. When reading such a photographic film, when reading a film image having a very high transmission density, the amount of light incident on the reading sensor is insufficient even if the amount of light emitted from the light source is increased, and the reading output from the reading sensor is not sufficient. Since the dynamic range of the signal is reduced and the gradient of the change in the level of the read signal with respect to the density change in the film image is reduced, the image data obtained by performing the A / D conversion on the read signal is This is low-gradation data with low resolution for image density. Therefore, if an image is recorded on a recording material using the above image data, there is a problem that a pseudo contour (a pattern such as a contour line) is generated on the recorded image.

The shortage of the amount of light incident on the reading sensor can be compensated to a certain extent by, for example, increasing the charge accumulation time if the reading sensor is a CCD sensor. This is not preferable because it leads to a decrease in the processing capability of the reading device. In order to solve this, for example, an amplifier at the front stage of the A / D converter is an amplifier whose gain can be adjusted from the outside, and the gain in amplifying the read signal increases as the amount of light incident on the read sensor decreases. It is possible.

However, since the read signal output from the read sensor is a signal of a relatively low level, the gain of the above-mentioned amplifier is stabilized with high accuracy during the amplification operation.
In addition, low noise is required. An amplifier that satisfies this requirement and is capable of externally adjusting the gain is very expensive. If an inexpensive amplifier capable of externally adjusting the gain is used, the accuracy of the image data may be reduced. .

Further, the above problem is not limited to the case where a film image recorded on a photographic film is read, and also the case where a document other than a photographic film is read.
Since the amount of light incident on the reading sensor greatly changes depending on the content of the document to be read, the content of the document to be read is such that the amount of light incident on the reading sensor is significantly reduced (for example, when the transmission density is low). It is difficult to obtain high-gradation data for a very high transmission original.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described circumstances, and has as its object to provide a document reading apparatus capable of acquiring high-gradation data that accurately represents the contents of a document regardless of the contents of the document.

[0008]

According to a first aspect of the present invention, there is provided a document reading apparatus, comprising: a reading sensor for receiving light from a document and outputting a reading signal corresponding to the amount of incident light; A plurality of amplifiers for amplifying read signals output from the read sensor with different gains; and a plurality of amplifiers respectively provided corresponding to the plurality of amplifiers, and converting the read signals amplified by the corresponding amplifiers into digital read data. A plurality of A / D converters to be converted and a selecting means for selecting one of a plurality of types of read data respectively output from the plurality of A / D converters are configured.

According to the first aspect of the invention, light from a document is incident on the reading sensor, and the reading sensor outputs a reading signal according to the amount of incident light. Note that the original according to the present invention may be a transparent original such as a photographic film or a reflective original, and even if the light incident on the reading sensor from the original or the light transmitted through the transparent original is reflected. The light reflected from the document may be used.

The document reading apparatus according to the first aspect of the present invention includes a plurality of amplifiers and A / D converters, and the read signal output from the reading sensor is amplified by the plurality of amplifiers at different gains. The data is converted into digital read data by a plurality of A / D converters.
Then, the selecting means selects one of the plurality of types of read data output from the plurality of A / D converters.

Although the amount of light incident on the reading sensor depends on the contents of the document (density or brightness of each part on the document), according to the above configuration, the amount of light incident on the reading sensor is small and the reading output from the reading sensor is small. When the dynamic range of the signal is small, the selecting means selects an A / D corresponding to an amplifier that amplifies the read signal with a relatively high gain among a plurality of types of read data output from the plurality of A / D converters. By selecting the read data output from the converter, it is possible to obtain high-gradation read data that accurately represents the contents of the document.

Further, the amount of light incident on the reading sensor is large,
If the dynamic range of the read signal output from the read sensor is large, the output signal may be saturated by an amplifier that amplifies the read signal with a relatively high gain. By selecting the read data output from the A / D converter corresponding to the amplifier that amplifies with a relatively low gain, it is possible to obtain high-gradation read data that accurately represents the contents of the document. Therefore, according to the first aspect of the present invention, it is possible to acquire high-gradation data that accurately represents the content of the document regardless of the content of the document.

In the first aspect of the present invention, since a plurality of amplifiers for amplifying the read signal with different gains are provided, it is not necessary to use an expensive amplifier capable of externally adjusting the gain as the amplifier. An inexpensive fixed gain amplifier can be used. As long as the amplifier has a fixed gain, an amplifier having the performance required for amplifying the read signal (the gain is stable with high precision during the amplification operation and the noise is low) can be obtained at low cost. , A / D converter can be obtained at a much lower cost than an amplifier capable of externally adjusting the gain, so even if a plurality of amplifiers and A / D converters are provided, the external gain can be adjusted. As compared with the case where an amplifier is used, the cost can be significantly reduced.

When the original to be read is a photographic film and a plurality of film images recorded on the photographic film are read, the amount of light incident on the reading sensor depends on the density of each film image. There is a possibility that there will be large variations for each image. For this reason, as described in claim 2, based on data of each film image obtained by preliminary reading each of the plurality of film images recorded on the photographic film, It is preferable to provide control means for controlling the selection by the selection means at the time of actual reading for each film image.

The preliminary reading of the film image may be performed by the reading sensor according to the present invention,
The reading may be performed by a sensor provided separately from the reading sensor. The amount of light incident on the reading sensor when the main reading is performed on each film image can be roughly estimated from data of each film image obtained by preliminary reading each of the plurality of film images. Therefore, as in claim 2,
Based on the data of each film image obtained by the preliminary reading, by controlling the selection by the selecting means at the time of performing the main reading for each film image, a plurality of film images can be obtained regardless of the variation in the density of each film image. From the film image, high-gradation data that accurately represents the contents of the film image can be obtained.

Each component color light (for example, light in the wavelength range corresponding to R (R light), light in the wavelength range corresponding to G (G light), light in the wavelength range corresponding to B (B light )), A reading sensor (so-called color sensor) that outputs a reading signal for each component color (for example, R, G, B) according to the amount of incident light is used. In many cases, the light amount and the sensitivity of the reading sensor are largely different for each component color.

For a component color in which the amount of light incident on the reading sensor at the time of reading a document is sufficiently large on average in comparison with the sensitivity of the reading sensor, for example, the amount of irradiation of the component color light onto the document is usually filtered by a filter or the like. When reading a document whose contents cause a decrease in the amount of light incident on the reading sensor beforehand, cancel the light reduction using a filter or the like to avoid the shortage of the amount of incident light of the component color light on the reading sensor. can do. However, for a specific component color in which the amount of light incident on the reading sensor when reading the document is smaller than the sensitivity of the reading sensor on average, when reading a document whose content causes a decrease in the amount of light incident on the reading sensor. In addition, it is difficult to avoid the shortage of the incident light amount of the specific component color light to the reading sensor.

In the above case, an amplifier and an A / D converter are provided for each component color, and the amount of incident light of each component color light on the reading sensor and the amount of light incident on the reading sensor are determined. It is preferable that the number of amplifiers and A / D converters is determined for each component color in accordance with the sensitivity of the reading sensor to each component color light. Specifically, for example, for a component color in which the amount of light incident on the reading sensor is smaller than the sensitivity of the reading sensor on average, the corresponding amplifier and A The number of / D converters is increased, and the number of corresponding amplifiers and A / D converters is reduced for component colors in which the amount of light incident on the reading sensor is larger on average than the sensitivity of the reading sensor. Thus, the number of amplifiers and A / D converters can be optimized for each component color, so that the number of amplifiers and A / D converters can be suppressed to a minimum.

Also, as described above, the amount of light incident on the reading sensor and the sensitivity of the reading sensor are greatly different for each component color, and an amplifier and an A / D converter are provided for each component color. As described in claim 4, the gain of the amplifier is preferably determined for each component color according to the amount of incident light of each component color light on the reading sensor and the sensitivity of the reading sensor to each component color light. . This allows
Since the gain of the amplifier can be optimized for each component color, it is possible to obtain high-gradation data that accurately represents the contents of the document for each component color.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. Hereinafter, the digital laboratory system according to the present embodiment will be described first.

(Schematic Configuration of Entire System) FIG. 1 shows a schematic configuration of a digital lab system 10 according to the present embodiment, and FIG. 2 shows an appearance of the digital lab system 10. As shown in FIG. 1, the lab system 10 includes a line CCD scanner 14, an image processing unit 1
6, a laser printer section 18 and a processor section 20. The line CCD scanner 14 and the image processing section 16 are integrated as an input section 26 shown in FIG. Part 20
Are integrated as an output unit 28 shown in FIG.

The line CCD scanner 14 is a film image recorded on a photographic photosensitive material such as a photographic film (for example, a negative film or a reversal film) (an original of the present invention, more specifically, a transparent original: hereinafter simply referred to as a photographic film). (A negative image or a positive image visualized by developing after subject is photographed). For example, a 135-size photographic film, a 110-size photographic film, and a transparent magnetic layer are formed. The film images of photographic film (240-size photographic film: so-called APS film) and photographic films of 120-size and 220-size (Brownie size) can be read. The line CCD scanner 14 reads the film image to be read by the line CCD and outputs image data.

The image processing unit 16 receives image data (scan data) output from the line CCD scanner 14 and obtains image data obtained by photographing with a digital camera and a document other than a film image (for example, a reflection document). ) Is input from outside (e.g., via a storage medium such as a memory card). Input from another information processing device via a communication line, etc.).

The image processing section 16 performs image processing such as various corrections on the input image data, and outputs the image data to the laser printer section 18 as recording image data. Also,
The image processing unit 16 outputs image data on which image processing has been performed to an external device as an image file (for example, outputs the image data to a storage medium such as a memory card, or transmits the image data to another information processing device via a communication line). It is also possible.

The laser printer unit 18 has R, G, and B laser light sources, and irradiates a photographic paper with laser light modulated in accordance with recording image data input from the image processing unit 16 to perform scanning exposure. To record an image on photographic paper. Further, the processor unit 20 performs each process of color development, bleach-fix, washing, and drying on the photographic paper on which the image is recorded by the scanning exposure by the laser printer unit 18. Thus, an image is formed on the printing paper.

(Structure of Line CCD Scanner) Next, the structure of the line CCD scanner 14, which forms a part of the original reading apparatus of the present invention, will be described. FIG. 3 shows a line CC.
The schematic configuration of the optical system of the D scanner 14 is shown. The line CCD scanner 14 is a work table 2 of the input unit 26.
7 is provided below. The light source unit 30 is accommodated in a metal casing 31, and a lamp 32 formed of a halogen lamp is disposed on the right side of the casing 31 (see FIG. 3A).
Note that a metal halide lamp may be used instead of the halogen lamp.

A reflector 33 is provided around the lamp 32, and a part of the light emitted from the lamp 32 is reflected by the reflector 33 and is reflected in a certain direction (FIG. 3).
(Left side in (A)). A fan 34 is provided on the opposite side of the reflector 33 from the light emission side. The fan 34 is operated while the lamp 32 is on, and prevents the inside of the casing 31 from being overheated. On the light exit side of the reflector 33, the light having a wavelength in the ultraviolet region and the infrared region is cut along the optical axis of the light emitted from the reflector 33, thereby preventing a temperature rise of the photographic film 22 and improving reading accuracy. A UV / IR cut filter 35, turrets 36 and 37, an aperture 39, and a light diffusion box 40 are provided in this order.

As shown in FIG. 4A, the turret 3
6 are provided with a plurality of holes 36A.
In the remaining holes 36A excluding the above, light of a specific component color of R, G, and B is dimmed and the specific component color (hereinafter, referred to as
Dimming filters 41 having different dimming rates for light of the first component color) are fitted respectively. The turret 37 has substantially the same configuration as the turret 36,
In the hole of the turret 37, a light control filter for reducing light of a component color different from that of the above-described light control filter 41 (hereinafter, referred to as a second component color) is fitted. Turrets 36, 3
Reference numeral 7 is arranged such that any one of the plurality of holes is located on the optical axis, and the holes located on the optical axis are sequentially switched by being rotated.

The stop 39 is composed of a pair of plate members arranged with the optical axis interposed therebetween, and is slidable so that the pair of plate members approaches and separates from each other. As shown in FIG. 4B, the pair of plate members of the aperture 39 continuously changes in cross-sectional area in a direction perpendicular to the sliding direction from one end side in the sliding direction to the other end side. As described above, the notches 39A are formed on one end side, and the cutouts 39A are arranged so that the sides on which the notches 39A are formed face each other.

In the above configuration, the ratio of the amount of light of the first component light to that of the other component color changes depending on which of the plurality of holes of the turret 36 is located on the optical axis. The ratio of the amount of light of the second component color to the amount of light of the other component color changes depending on which of the plurality of holes is located on the optical axis, and the amount of light passing through the diaphragm 39 depends on the position of the diaphragm 39. Changes. Therefore, the amounts of the component color lights emitted through the turrets 36 and 37 and the stop 39 can be uniformly adjusted by the turrets 36 and 37 and the stop 39 without spatially causing color unevenness.

The light diffusion box 40 has a substantially L-shape in which an intermediate portion is bent at a right angle, and inside the bent portion, the light incident on the inside of the light diffusion box 40 is emitted in directions different by 90 °. A total reflection mirror is provided. The light diffusion box 40 has a light exit opening in a direction (width direction of the photographic film 22) orthogonal to the conveyance direction of the photographic film 22 conveyed by a film carrier 38 (details will be described later) set on the work table 27. It has a flat rectangular shape as a longitudinal direction (see FIGS. 3A and 3B), and a dimension along the width direction of the photographic film 22 is tapered from the bent portion toward the light exit port. Has been gradually increased. Light diffusion plates 42A and 42B are attached to the light incident side and the light emission side of the light diffusion box 40, respectively.

Accordingly, the light incident on the light diffusion box 40 is transmitted to the film carrier 38 (that is, the photographic film 2).
The optical path is bent 90 ° toward 2), and slit light having a longitudinal direction in the width direction of the photographic film 22 is formed.
The light is further diffused by the light diffusion plates 42A and 42B and emitted.

On the opposite side of the light source unit 30 with the work table 27 interposed therebetween, a reading unit 43 is disposed in a state housed in a casing 44. A support frame 45 is erected on the work table 27, and the casing 44 is supported by the support frame 45 so as to be slidable in a direction approaching and separating from the work table 27. A mounting table 47 is provided inside the casing 44, and a plurality of support rails 49 hang down from the mounting table 47. A lens unit 50 is supported on the support rail 49 so as to be slidable in a direction approaching and moving away from the work table 27.

The lens unit 50 includes a plurality of lenses, and a lens diaphragm 51 is provided between the plurality of lenses. As shown in FIG. 4C, the lens diaphragm 51 includes a plurality of diaphragm plates 51A formed in a substantially C shape. Each of the aperture plates 51A is evenly arranged around the optical axis, one end of which is supported by a pin, and is rotatable about the pin. The plurality of aperture plates 51A are connected via a link (not shown), and rotate in the same direction when a driving force of a lens aperture drive motor (described later) is transmitted. With the rotation of the diaphragm plate 51A, the area of the portion not shielded by the diaphragm plate 51A around the optical axis (the substantially star-shaped portion in FIG. 4C) changes and passes through the lens diaphragm 51. The amount of light changes.

On the upper surface of the mounting table 47, a line CCD 116 is provided.
Is installed. The line CCD 116 has a large number of photoelectric conversion elements such as CCD cells and photodiodes arranged in a line, and three sensing units provided with an electronic shutter mechanism provided in parallel with each other at intervals. One of R, G, and B color separation filters is attached to the light incident side (a so-called three-line color CCD). In addition, a transfer section composed of a large number of CCD cells is provided in the vicinity of each sensing section corresponding to each sensing section, and charges accumulated in each CCD cell of each sensing section are transferred to the corresponding transfer section. Are transferred in order through. The line CCD 116 corresponds to the reading sensor of the present invention.

On the light incident side of the line CCD 116,
A CCD shutter 52 for dark correction of the line CCD 116 is provided. The CCD shutter 52 has N
D filter is attached (not shown), and line C
A fully closed state in which light entering the CD 116 is blocked, a fully open state in which light enters the line CCD 116, a line CCD
The light is switched to one of the dimming states in which the light incident on the light 116 is dimmed by the ND filter.

FIG. 5 shows a schematic configuration of an electric system of the line CCD scanner 14. Line CCD scanner 1
4 includes a microprocessor 46 for controlling the entire line CCD scanner 14. The microprocessor 46 has a RAM 64 (for example, SRA
M), ROM 66 (for example, RO whose storage contents can be rewritten)
M), and the lamp driver 53 and the motor driver 48 are connected. The lamp driver 53 turns on and off the lamp 32 according to an instruction from the microprocessor 46.

The motor driver 48 includes a turret driving motor 54 for rotating the turrets 36 and 37 independently of each other so that any one of the plurality of holes of the turrets 36 and 37 is positioned on the optical axis. 36, 3
Turret position sensor 55 for detecting the position (rotation angle) 7, aperture drive motor 5 for slidingly moving aperture 39
6. A diaphragm position sensor 57 for detecting the position of the diaphragm 39 and a casing 44 containing the reading unit 43
A reading unit driving motor 58 that slides along the scanning unit, a reading unit position sensor 59 that detects the position of the casing 44 (that is, the reading unit 43), and a lens driving motor 6 that slides the lens unit 50 along the support rail 49.
0, a lens position sensor 61 for detecting the position of the lens unit 50, a lens diaphragm drive motor 62 for rotating the diaphragm plate 51A of the lens diaphragm 51, and a lens diaphragm position for detecting the position of the lens diaphragm 51 (the position of the diaphragm plate 51A). Sensor 6
3. A shutter drive motor 64 for switching the CCD shutter 52 to one of a light-shielding state, a non-light-shielding state, and a dimming state is connected.

The microprocessor 46 has a line CCD.
When the film image is read (photometric) by the turret position sensor 55 and the aperture position sensor 57
Turrets 36 and 37 and aperture 39 detected by
The turret drive motor 54 rotates the turrets 36 and 37 based on the position, and the iris 39 is slid by the iris drive motor 56 to adjust the amount of light applied to the film image for each component color light.

The microprocessor 46 determines a zoom magnification according to the size of the film image, whether or not to perform trimming, and the like, so that the film image is read by the line CCD 116 at the determined zoom magnification.
Casing 4 detected by reading unit position sensor 59
The casing 44 is slid by the reading unit drive motor 58 based on the position of the lens unit 4, and the lens unit 5 is driven by the lens drive motor 60 based on the position of the lens unit 50 detected by the lens position sensor 61.
Slide 0.

When focusing control (autofocus control) for matching the light receiving surface of the line CCD 116 with the image forming position of the film image by the lens unit 50 is performed, the microprocessor 46 controls only the casing 44 by the reading unit drive motor 58. To slide. This focusing control can be performed, for example, so that the contrast of the film image read by the line CCD 116 is maximized (so-called image contrast method). Alternatively, the photographic film and the lens unit 50 (or the line CCD 116) may be used. May be provided based on a distance detected by the distance sensor instead of film image data.

The line CCD 116 is a three-line color CCD sensor as described above. In FIG. 5, for convenience, the line CCD 116 is connected to an R line sensor 116R for outputting an R read signal corresponding to the amount of incident R light. And G
A G line sensor 116G that outputs a G read signal according to the amount of incident light of light and a B line sensor 116B that outputs a B read signal according to the amount of incident light of B light are shown separately. A timing generator 74 is connected to the line CCD 116.
Are line sensors 116R, 1
It generates various timing signals (clock signals) for controlling accumulation and transfer of charges in the 16G and 116B and for operating an A / D converter and the like described later.

R line sensor 11 of line CCD 116
A signal output terminal 6R (a signal output terminal for outputting a read signal of R) is provided with a level adjuster 9 for shifting the level of the read signal.
It is connected to an A / D converter 94 via a 2R and an amplifier 93. The amplifier 93 sets the average level of the R read signal output from the line CCD 116 (the level of the R read signal is determined according to the amount of R light incident on the line CCD 116 and the sensitivity of the line CCD 116 to the R light). The gain is fixedly determined (for example, gain =
1.0), the read signal of R output from the line CCD 116 is amplified by a predetermined gain by the amplifier 93 after the level is shifted by the level adjuster 92R, and is converted into digital data (read data of R by the A / D converter 94). ).

The output terminal of the A / D converter 94 is connected to an interface (I / F) circuit 90 via a correlated double sampling circuit (CDS) 88R. CDS88R
Then, the feedthrough data representing the level of the feedthrough signal and the pixel data representing the level of the pixel signal are each sampled, and the feedthrough data is subtracted from the pixel data for each pixel. Then, the calculation result (pixel data accurately corresponding to the amount of charge stored in each CCD cell of the R line sensor 116R) is sequentially output to the image processing unit 16 as R scan data via the I / F circuit 90.

The signal output terminal (signal output terminal for outputting a G read signal) of the G line sensor 116G of the line CCD 116 is also connected to the A / D via the level adjusting unit 92G for shifting the level of the read signal and the amplifier 95. It is connected to a converter 96. The amplifier 95 also responds to the average level of the G read signal output from the line CCD 116 (the level of the G read signal is determined according to the amount of G light incident on the line CCD 116 and the sensitivity of the line CCD 116 to the G light). The gain is fixedly set (for example, gain = 1.0), and the G read signal output from the line CCD 116 is also amplified with a predetermined gain by the amplifier 95 after the level is shifted by the level adjuster 92G. The data is converted into digital data (G read data) by an A / D converter 96. The output terminal of the A / D converter 96 is connected to the I / F circuit 90 via the CDS 88G having the same configuration as the CDS 88R, and the G scan data is sequentially output from the CDS 88G to the image processing unit 16.

A signal output terminal of the B line sensor 116B of the line CCD 116 (a signal output terminal for outputting a B read signal) is connected to an input terminal of a level adjusting unit 92B for shifting the level of the read signal. Level adjuster 92
The output terminal of B is connected to the input terminals of the amplifiers 97A and 97B, respectively. An output terminal of the amplifier 97A is an A / D converter 98.
A, and the output terminal of the amplifier 97B is connected to the A / D converter 98B. The amplifiers 97A and 9A
7B corresponds to a plurality of amplifiers of the present invention, and A / D converters 98A and 98B correspond to a plurality of A / D converters of the present invention.

The amplifier 97A is configured to read an average level of the B read signal output from the line CCD 116 when reading a film image whose density is less than a predetermined value (the level of the B read signal is such that the B light is incident on the line CCD 116). The gain is fixedly determined according to the light amount and the sensitivity of the line CCD 116 to the B light), and the amplifier 97B is output from the line CCD 116 when reading a film image whose density is equal to or more than a predetermined value. The gain is fixedly determined according to the average level of the B read signal.

Therefore, the gain of the amplifier 97B is
7A (for example, amplifier 97
A is gain = 1.0, amplifier 97B is gain = 3.0, etc.),
The read signal of B output from the line CCD 116 is also amplified at different gains by the amplifiers 97A and 97B after the level is shifted by the level adjuster 92G, and is converted into digital data (B) by the A / D converters 98A and 98B. Is read data).

The output terminal of the A / D converter 98A is connected to the selector 9
9 is connected to one of the two input terminals, and the output terminal of the A / D converter 98B is connected to the other of the two input terminals of the selector 99. The output terminal of the selector 99 is CDS88.
R, I / F via CDS88B having the same configuration as 88G
The control signal input terminal of the selector 99 is connected to the microprocessor 46. The selector 99 corresponds to the selection means of the present invention. Of the two types of read data respectively input from the A / D converters 98A and 98B via the two input terminals, the selector 99 is usually an A / D converter. The read data input from 98A is output to CDS 88B, and when an instruction to switch the output is issued from microprocessor 46, the read data input from A / D converter 98B is output to CDS 88B. The B scan data is sequentially output from the CDS 88B to the image processing unit 16.

As described above, the R, G, and B read signals are output in parallel from the line CCD 116, and the output R, G, and B read signals are processed in parallel by the above-described signal processing system. / F circuit 90 outputs R, G, and B image data (scan data) in parallel.

Amplified by different gains and A
In order to selectively output a plurality of types of read data subjected to the / D conversion, for example, a signal processing system for a B read signal is provided with a selector on the output side of the amplifiers 97A and 97B, and a selector is selectively provided from the selector. A / D conversion can be performed by a single A / D converter on the analog read signal output to the analog read signal. Since the selector is expensive, it is better to provide two A / D converters (A / D converters 98A and 98B) and to provide a selector 99 for digital data on the output side of the A / D converter as described above. Thus, the apparatus can be configured at low cost.

(Configuration of Image Processing Unit) Next, the image processing unit 16
Will be described with reference to FIG. Image processing unit 1
Reference numeral 6 is provided with a line scanner correction unit 122 corresponding to the line CCD scanner 14. The line scanner correction unit 122 includes a signal processing unit including a dark correction circuit 124, a defective pixel correction unit 128, and a light correction circuit 130 corresponding to the R, G, and B scan data output in parallel from the line CCD scanner 14. Three systems are provided.

The dark correction circuit 124 includes a line CCD 116
The data (data representing the dark output level of each cell of the sensing unit of the line CCD 116) input from the line CCD scanner 14 in a state where the light incident side is shielded by the CCD shutter 52 is stored for each cell. When the line CCD 116 reads the photographic film 22, the correction is performed by reducing the dark output level of the cell corresponding to each pixel from the scan data input from the line CCD scanner 14.

Also, the photoelectric conversion characteristics of the line CCD 116 vary from cell to cell. Defective pixel correction unit 12
In the bright correction circuit 130 at the subsequent stage of 8, the line CCD 116 reads the adjustment film image with the line CCD 116 while the film image for adjustment having a constant density is set on the entire screen of the line CCD scanner 14.
A gain is determined for each cell based on the image data of the adjustment film image input from the scanner 14 (the density variation of each pixel represented by this image data is caused by the variation of the photoelectric conversion characteristics of each cell). Previously, line CCD
The scan data of the film image to be read input from the scanner 14 is corrected for each pixel according to the gain determined for each cell.

On the other hand, if the density of a specific pixel is significantly different from the density of other pixels in the image data of the film image for adjustment, the cell of the line CCD 116 corresponding to the specific pixel has some abnormality. The specific pixel can be determined as a defective pixel. Defective pixel correction unit 12
8 stores the address of the defective pixel based on the image data of the film image for adjustment,
Among the scan data of the film image to be read inputted from 4, the data of the defective pixel is newly generated by interpolating from the data of the surrounding pixels. Since the number of CCD cells in the line CCD is smaller than that in the area CCD, the defective pixel correction unit 128 has a simple configuration.

Since three lines (CCD cell rows) are arranged in the line CCD 116 at predetermined intervals along the direction in which the photographic film 22 is transported, the line CCD scanner 14 outputs R, G, B. There is a time difference in the timing at which the output of the scan data of each component color is started. The line scanner correction unit 122 delays the scan data output timing with a different delay time for each component color so that R, G, and B data of the same pixel is simultaneously output on the film image.

The output terminal of the line scanner correction unit 122 is connected to the input terminal of the selector 132.
Is output to the selector 132.
The input terminal of the selector 132 is connected to the input / output controller 1.
It is also connected to a data output terminal of the selector 34, and externally input file image data is input to the selector 132 from the input / output controller 134. Selector 132
Are connected to the input / output controller 134 and the data input terminals of the image processors 136A and 136B, respectively. The selector 132 can selectively output the input image data to each of the input / output controller 134 and the image processors 136A and 136B.

The image processor 136A includes a memory controller 138, an image processor 140, and three frame memories 142A, 142B, 142C. Frame memories 142A, 142B, 142C
Has a capacity capable of storing image data of a film image for one frame, and the image data input from the selector 132 is stored in any of the three frame memories 142. The memory controller 138 The data of each pixel of the input image data is stored in the frame memory 14.
2 so that they are stored in a certain order in the storage area,
The address at which the image data is stored in the frame memory 142 is controlled.

The image processor 140 takes in the image data stored in the frame memory 142, performs gradation conversion, color conversion, hypertone processing for compressing the gradation of an ultra-low frequency luminance component of the image, and sharpness while suppressing graininess. Various image processing such as hyper sharpness processing for emphasizing is performed. Note that the processing conditions of the above image processing are automatically calculated by an auto setup engine 144 (described later), and the image processing is performed according to the calculated processing conditions. The image processor 140 is connected to the input / output controller 134, and the image data subjected to the image processing is temporarily stored in the frame memory 142 and then output to the input / output controller 134 at a predetermined timing. Note that the image processor unit 136B has the same configuration as the above-described image processor unit 136A, and a description thereof will be omitted.

In the present embodiment, each line image is read twice by the line CCD scanner 14 at different resolutions. In the first reading at a relatively low resolution (hereinafter, referred to as pre-scan), even when the density of the film image is extremely low (for example, a negative image of an underexposure in a negative film), a line CCD is used.
The film image (photographic film 22) is obtained under the reading conditions (light amounts of the light irradiating the photographic film 22 for each of the R, G, and B wavelength ranges, and the charge storage time of the CCD) determined so as not to cause the saturation of the stored charge at 116. ) Is performed. Data (pre-scan data) obtained by this pre-scan is sent from the selector 132 to the input / output controller 134.
, And further output to an auto setup engine 144 connected to the input / output controller 134.

The auto setup engine 144 has a C
PU 146, RAM 148 (for example, DRAM), ROM
150 (for example, a rewritable ROM) and an input / output port 152, which are connected to each other via a bus 154.

The auto setup engine 144 determines a film image based on the pre-scan data input from the input / output controller 134, and extracts data (pre-scan image data) of an area corresponding to the film image. Then, the type (size, density, etc.) of the film image is determined from the pre-scan image data, the frame position and the type are output to the line CCD scanner 14, and based on the pre-scan image data of the film images for a plurality of frames. Image processing conditions for image data (fine scan image data) obtained by the second relatively high-resolution reading by the line CCD scanner 14 (hereinafter referred to as fine scan) are calculated, and the calculated processing conditions are stored in an image processor. Output to the image processor 140 of the unit 136.

In the calculation of the processing conditions of the image processing, it is determined whether or not there are a plurality of film images obtained by shooting similar scenes based on the exposure amount at the time of shooting, the type of light source for shooting, and other characteristic amounts. If there are a plurality of photographed film images, it is determined that the processing conditions of the image processing for the fine scan image data of these film images are the same or similar.

The optimum processing conditions for image processing also vary depending on whether the image data after image processing is used for recording an image on photographic paper in the laser printer unit 18 or output to the outside. Since the image processing unit 16 is provided with two image processor units 136A and 136B, for example, when the image data is used for recording an image on photographic paper and is output to the outside, the auto setup engine 144 is used. Calculates the optimal processing conditions for each application, and calculates the image processor units 136A and 136A.
Output to B. Thereby, the image processor unit 13
6A and 136B, the same fine scan image data is subjected to image processing under different processing conditions.

Further, the auto setup engine 144
Calculates an image recording parameter that defines a gray balance and the like when recording an image on photographic paper by the laser printer unit 18 based on the pre-scan image data of the film image input from the input / output controller 134, The image data is output simultaneously when the image data for recording (described later) is output to the printer unit 18. Further, the auto setup engine 144 calculates the processing conditions of the image processing for the file image data input from the outside in the same manner as described above.

The input / output controller 134 is an I / F circuit 1
It is connected to the laser printer section 18 via 56.
When the image data after image processing is used for recording an image on photographic paper, the image data processed by the image processor 136 is transferred from the input / output controller 134 via the I / F circuit 156 to the recording image. The data is output to the laser printer unit 18 as data. The auto setup engine 144 is connected to a personal computer 158. When the image data after the image processing is output to the outside as an image file, the image data processed by the image processor unit 136 is sent from the input / output controller 134 to the auto setup engine 144.
Is output to the personal computer 158 via the.

The personal computer 158 has a CPU
160, memory 162, display 164 and keyboard 166 (see also FIG. 2), hard disk 168, C
It includes a D-ROM driver 170, a transport control unit 172, an expansion slot 174, and an image compression / decompression unit 176.
These are connected to each other via a bus 178. The transport controller 172 is connected to the film carrier 38 and controls the transport of the photographic film 22 by the film carrier 38. In addition, the film carrier 38
When an APS film is set in the APS film, information (for example, print size, etc.) read from the magnetic layer of the APS film by the film carrier 38 is input.

A driver (not shown) for reading / writing data from / to a storage medium such as a memory card.
A communication control device for communicating with another information processing device is connected to the personal computer 158 via the expansion slot 174. When image data for output to the outside is input from the input / output controller 134, the image data is output to the outside (the driver, the communication control device, or the like) as an image file via the expansion slot 174. When file image data is input from outside via the expansion slot 174, the input file image data
4 to the input / output controller 134. In this case, the input / output controller 134 outputs the input file image data to the selector 132.

The image processing section 16 outputs prescanned image data and the like to the personal computer 158,
The film image read by the line CCD scanner 14 is displayed on the display 164, or the image obtained by recording on the photographic paper is estimated and displayed on the display 164, and the operator can correct the image via the keyboard 166. When instructed, this can be reflected in the processing conditions of image processing.

(Operation) Next, as an operation of the present embodiment, a reading condition calculation process (FIG. 7) executed by the auto setup engine 144 of the image processing unit 16 when a film image recorded on the photographic film 22 is read. ) And the film image reading process (FIG. 8) executed by the microprocessor 46 of the line CCD scanner 14.

In the reading condition calculation processing, in step 200, predetermined reading conditions (the turrets 36 and 37, the position of the aperture 39, the line sensors 116R, 116G and 116B of each color) when pre-scanning the film image are performed.
, Etc.) to the line CCD scanner 14 and instruct the line CCD scanner 14 to perform a pre-scan on the film image recorded on the photographic film 22. Note that as the reading conditions in the pre-scan, standard reading conditions capable of reading most film images (film images having a density within a predetermined range) with high accuracy are used.

In step 202, it is determined whether or not pre-scan data has been input from the line CCD scanner 14. If the determination is negative, the process proceeds to step 204, where it is determined whether prescan data for one photographic film has been input. If this determination is also negative, the process returns to step 202, and the determination of steps 202 and 204 is repeated.

On the other hand, in the film image reading process, it is determined in step 250 whether or not the execution of the pre-scan has been instructed, and the process waits until the determination is affirmed. When the execution of the prescan is instructed, the determination in step 250 is affirmed, and the process proceeds to step 252 to instruct the film carrier 38 to convey the photographic film 22 in a predetermined direction (forward direction). As a result, the film carrier 38 starts transporting the photographic film 22 at a constant transport speed suitable for prescan.

In step 254, the turrets 36, 3 are read so as to perform reading under the pre-scanning reading conditions notified from the auto setup engine 144.
7. Move the aperture 39 to the line sensor 116 for each color.
After setting the charge accumulation times of R, 116G, and 116B, a pre-scan for preliminarily reading the entire surface of the photographic film 22 by the line CCD 116 of the line CCD scanner 14 is performed. At the time of this prescan, the selector 99 is not instructed to switch the output.

As a result, the R read signal sequentially output from the R line sensor 116R of the line CCD 116 is:
The level is shifted by the level adjuster 92R, amplified by a predetermined gain by the amplifier 93, converted into read data by the A / D converter 94, and sequentially input to the image processor 16 as prescan data of R via the CDS 88R. Is done. The level of the G read signal sequentially output from the G line sensor 116G is shifted by a level adjuster 92G, amplified by a predetermined gain by an amplifier 95, and converted into read data by an A / D converter 96. , CDS88G, and is sequentially input to the image processing unit 16 as G prescan data.

The read signals of B sequentially output from the B line sensor 116B are amplified by amplifiers 97A and 97B with different gains after their levels are shifted by the level adjuster 92B, and the A / D converters are used. The read data is converted by the respective A / D converters 98A and 98B. At this time, the read data (amplifier) output from the A / D converter 98A among the two types of read data output from the A / D converters 98A and 98B. The data obtained by performing A / D conversion on the read signal amplified with a low gain by 97A) is selected by the selector 99, and the selected read data is passed through the CDS 88B as prescan data of B, and is processed by the image processing unit. 16 are sequentially input.

In the next step 256, it is determined whether or not the entire surface of one photographic film has been read. If the determination is negative, the process returns to step 254, and step 2
54, 256 are repeated. If the determination in step 256 is affirmative, the pre-scan ends and the process proceeds to step 258.

The R, G, and B scan data input from the line CCD scanner 14 to the image processing unit 16 is stored in the RAM 148 of the auto setup engine 144 via the line scanner correction unit 122. In the reading condition calculation processing (FIG. 7), the scan data is stored in the RAM 148.
Is stored in a predetermined amount (e.g., for one frame of film image), the determination in step 202 is affirmed, and step 20 is performed.
6, the position (frame position) of the area where the film image is recorded on the photographic film 22 is determined from the input pre-scan data, and the image data (pre-scan image data) corresponding to the film image recording area is determined. ) Cut out.

In step 208, the reading conditions for performing the fine scan on the same film image are calculated based on the pre-scan image data cut out in step 206, and stored in the RAM 148 in association with the frame numbers. Further, in step 210, the exposure amount, photographing light source type and other characteristic amounts at the time of photographing the film image are obtained based on the pre-scan image data cut out in step 206, and the same film image is obtained based on the obtained characteristic amounts. The image processing conditions for fine scan image data obtained by performing a fine scan on the image data are calculated. Then, the calculated processing condition is stored in the RAM 148 in association with the frame number.

In the next step 212, step 206
It is determined whether or not the density of the film image corresponding to the pre-scan image data is equal to or higher than a predetermined value, based on the pre-scan image data cut out in step. This determination may be made by comparing the average densities of R, G, and B of the film image with a threshold, or by comparing the average density of B of the film image with the threshold. If the determination is negative, the process returns to step 202 without performing any processing. On the other hand, if the determination in step 212 is affirmative, the density of the film image is very high (for example, over-negative or super-over-negative in a negative image). The possibility of light quantity shortage is very high.

That is, in the present embodiment, a halogen lamp is used as the lamp 32, but the halogen lamp generally emits less B light than the R light and the G light. Also, among various photographic films to be read by the line CCD scanner 14, the line CCD scanner 14
135-size negative film with the largest throughput in
It is known that the film base has spectral characteristics in which the amount of transmitted light in the B wavelength range is small (the transmission density of B is high). Therefore, especially when reading a 135-size negative film, the incident light amount of the B light to the line CCD 116 is steadily obviously smaller than the incident light amounts of the R light and the G light. Furthermore, the line CCD 11 according to the present embodiment
No. 6 has a sensitivity characteristic in which the sensitivity to B light is clearly smaller than the sensitivity to R light and the sensitivity to G light.

Therefore, when reading a film image having a very high density, there is a very high possibility that the amount of incident light of B light on the line CCD 116 becomes insufficient compared with the sensitivity of the line CCD 116 to B light. In particular, since image data obtained by fine scan described later is used for recording an image on a recording material, it is necessary to accurately read a film image. For this reason, if the determination in step 212 is affirmative, the process proceeds to step 214, and the frame number of the film image corresponding to the pre-scan image data cut out in step 206 is
Is stored in the RAM 148 as the frame number of the film image for which the gain is switched with respect to the read signal, and the process returns to step 202.

Prescanning is performed on the entire surface of one photographic film 22, and prescanned image data is cut out for all film images recorded on the photographic film 22, and reading conditions for fine scan are set. Calculation,
When the calculation of the processing conditions of the image processing for the fine scan image data and the storage of the frame number of the film image whose density is equal to or more than the predetermined value are performed, the determination in step 204 is affirmed, and the process proceeds to step 216 to calculate first RAM148
The line CCD scanner 14 notifies the line CCD scanner 14 of the reading conditions at the time of fine scanning for each film image and the previously determined frame position of each film image.

In step 218, it is determined whether or not the frame number of the film image whose gain is to be switched is stored in the RAM 148. If the determination is negative, the process proceeds to step 222 without performing any processing. If the determination in step 218 is affirmative, step 220 is performed.
To notify the line CCD scanner 14 of the frame number of the film image for gain switching stored in the RAM 148. Then, in the next step 222, the execution of fine scan is instructed to the line CCD scanner 14.

In the next step 224, the processing conditions of the image processing for the fine scan image data of each film image previously calculated and stored in the RAM 148 are notified to the image processor 140 of the image processor 136, and the reading condition calculation is performed. The process ends.

In the film image reading process (FIG. 8), when the pre-scan is completed, the flow shifts to step 258 to determine whether or not the execution of the fine scan has been instructed, and waits until the determination is affirmed. When the execution of the fine scan is instructed as described above, the determination in step 258 is affirmed, and the process proceeds to step 260. In step 260 and thereafter, the fine scan of each film image recorded on the photographic film 22 is performed. That is, in step 260, the transport of the photographic film 22 in the direction (return direction) opposite to the predetermined direction is instructed to the film carrier 38. As a result, the film carrier 38 starts transporting the photographic film 22 at a constant transport speed suitable for fine scanning.

In the next step 262, the line CCD 116 is set on the basis of the notified frame position of each film image.
It is determined whether or not the film image has arrived at the film image reading position according to. If the determination is negative, step 2
The process proceeds to 64, and it is determined whether all the film images recorded on one photographic film 22 have been read. If this determination is also negative, the process returns to step 262, and steps 260 and 262 are repeated. Step 26
If the determination of 2 is affirmative, the process proceeds to step 266, and it is determined whether or not the film image that has reached the reading position is the gain switching target film image based on the notified frame number of the gain switching target film image.

If the determination in step 266 is negative, the process proceeds to step 270 without performing any processing.
After the turrets 36 and 37 and the aperture 39 are moved and the charge accumulation time of the line sensors 116R, 116G and 116B of each color is set so that reading is performed under the reading conditions at the time of fine scanning notified from the auto setup engine 144, Then, a fine scan is performed in which the film image reaching the reading position is read by the line CCD 116 at a relatively high resolution.

Thus, the read signal of R is supplied to the level adjuster 92R, the amplifier 93, the A / D converter 94, and the CDS 88.
The read signal of G is input to the image processing unit 16 as fine scan data of R via R,
The data is input to the image processing unit 16 as G fine scan data via the G, the amplifier 95, the A / D converter 96, and the CDS 88G.

On the other hand, if the determination in step 266 is denied as described above, since the density of the film image that has reached the reading position is less than the predetermined value, the amount of B light incident on the line CCD 116 is relatively large. It is estimated that the dynamic range of the B read signal output from the line CCD 116 is also relatively large. Therefore, the output signal may be saturated in the amplifier 97B that amplifies the read signal with a relatively high gain.

On the other hand, the read signal of B is amplified by amplifiers 97A and 97B with different gains through a level adjusting section 92B and converted into read data by A / D converters 98A and 98B. If the determination in step 266 is negative, the read data output from the A / D converter 98A (the data obtained by performing A / D conversion on the read signal amplified with a low gain by the amplifier 97A). ) Is selected by the selector 99, and the selected read data is input to the image processing unit 16 as fine scan data of B via the CDS 88B. This makes it possible to obtain high gradation B fine scan data that accurately represents the B density of the film image.

If the film image that has reached the reading position is a film image whose gain is to be switched, the determination in step 266 is affirmed and the process proceeds to step 268 to instruct the selector 99 to switch the output. Thereafter, the process proceeds to step 270 described above. Steps 266 and 268 described above, together with steps 212 and 214 of the reading condition calculation processing (FIG. 7), correspond to the control means described in claim 2.

If the determination in step 266 is affirmative,
Since the density of the film image that has reached the reading position is equal to or higher than the predetermined value, it is estimated that the amount of incident B light on the line CCD 116 is small and the dynamic range of the B read signal output from the line CCD 116 is also small. Therefore, the signal A / A is amplified by the amplifier 97A with a relatively low gain.
The level of the read signal input to the D converter 98A is insufficient for the signal level for performing A / D conversion properly,
The read data output from the D converter 98A is low-gradation data having a low resolution with respect to the B density of the film image.

On the other hand, if the determination in step 266 is affirmative, the selector 99 reads the read data output from the A / D converter 98B (at a high gain by the amplifier 97B) in accordance with an instruction from the microprocessor 46. (A / D conversion is performed on the amplified read signal), and the selected read data is stored in the CDS88.
Through B, it is output to the image processing unit 16 as fine scan data of B. Accordingly, even when the density of the film image to be read is equal to or higher than the predetermined value, fine gradation B fine scan data that accurately represents the B density of the film image can be obtained.

When the density of the film image is equal to or higher than a predetermined value, the ratio of transmission of the R light and the G light applied to the film image through the film image decreases, but the lamp 32 (halogen lamp) emits the R light and the G light. The amount of emitted light is large, 135
Film base of negative film of size is also R light and G
In the present embodiment, since the line CCD 116 has a sensitivity characteristic of high sensitivity to R light and high sensitivity to G light because of its spectral characteristics with a small amount of transmitted light (high transmission density of R and G). For film images whose density is less than the predetermined value (film images that are not subject to gain switching),
The reading condition is determined so that the R light and the G light emitted from the lamp 32 are dimmed by the dimming filter or the diaphragm 39.

For this reason, in this embodiment, a light control filter or an aperture 3 is used for a film image having a density equal to or higher than a predetermined value.
The reading conditions are set so that the dimming of the R light and the G light by the light emitting device 9 is canceled. Accordingly, it is possible to avoid shortage of the incident light amounts of the R light and the G light on the line CCD 116, and it is necessary to provide a plurality of amplifiers and A / D converters corresponding to the R read signal and the G read signal. Disappears. Therefore, the number of amplifiers and A / D converters can be reduced to a minimum.

When fine scanning is performed on a single film image in step 270, in the next step 272, the selector 99 selects the read data output from the A / D converter 98B (normal state). Thus, the selector 99 is instructed to switch the output, and the process returns to step 262. The output switching instruction of the selector 99 in this step 272 is issued when the selector 99
The determination is performed only when the read data output from the D converter 98B is selected (when the determination in step 266 is affirmative and the processing in step 268 is performed), and the selector 99 returns to the normal state. If the answer is YES (if the determination in step 266 is negative), the process returns to step 262 without performing any processing.

Until the fine scan for all the film images recorded on the photographic film 22 is completed (until the determination in step 264 is affirmed), each time the film image reaches the reading position. In step 262, the determination in step 262 is affirmed, and fine scan is performed on the film image that has reached the reading position in steps 266 to 272. Then, the fine scan image data of each film image input from the line CCD scanner 14 to the image processing unit 16 is output to the image processor unit 136.
In, image processing is performed in accordance with the processing conditions calculated for each film image by the auto setup engine 144, and output.

In the above description, a film image whose density is determined to be a predetermined value or more from the prescan image data is
Although the gain for the read signal of B at the time of the fine scan is simply increased, the present invention is not limited to this.
Since it is estimated that the precision of the pre-scan image data of the film image is also low, for a film image whose density is determined to be equal to or higher than the predetermined value, (the density is equal to or higher than the second threshold higher than the threshold in the determination. Only the determined film image may be targeted), or the pre-scanning may be performed again by changing the reading conditions.

In the above, two amplifiers 97A and 97B are provided as amplifiers for amplifying the read signal of B,
An A / D converter is provided for each amplifier. However, the present invention is not limited to this.
A plurality of amplifiers are provided, and A
A / D converter may be provided. In this case, the amplifier to be used may be switched according to the deviation amount of the density of the film image to be read from the standard density. Further, the amplifier and the A and the A correspond to read signals of component colors other than B.
It goes without saying that a plurality of / D converters may be provided.

In the above description, the three-line color CCD 116 has been described as an example of the reading sensor according to the present invention. However, the present invention is not limited to the line sensor, and an area sensor may be used. Further, the present invention is not limited to a color sensor, and the invention of claim 1 can be applied to a monochrome reading sensor. Further, another image sensor such as a MOS image sensor may be used as the reading sensor.

Further, the case where the photographic film 22 is read as an original according to the present invention has been described above as an example. However, the present invention is not limited to this, and the original may be a recording material such as photographic paper, plain paper, or thermal paper. It is also possible to apply the present invention to a scanner (for example, a scanner of a copier) that applies a reflective original and reads the recording material (the image recorded on the recording material).

[0103]

As described above, according to the first aspect of the present invention, a plurality of amplifiers amplify a read signal output from a read sensor in accordance with the amount of incident light from a document with different gains. Each of the read signals amplified by the amplifiers is converted into digital read data by a plurality of A / D converters, and one of a plurality of types of read data output from the plurality of A / D converters is converted into one. Since the selection is made, there is an excellent effect that high-gradation data that accurately represents the content of the document can be obtained regardless of the content of the document.

According to a second aspect of the present invention, in the first aspect of the invention, based on each film image data obtained by preliminary reading each of a plurality of film images recorded on a photographic film, Since the selection by the selecting means when performing the main reading for each film image is controlled for each film image, in addition to the above-described effects, a plurality of film images can be obtained regardless of the density variation of each film image. Therefore, it is possible to obtain high-gradation data that accurately represents the contents of the film image.

According to a third aspect of the present invention, in the first aspect of the present invention, an amplifier and an A / D converter are provided for each component color, and the amount of incident light of each component color light on the reading sensor and the reading sensor Depending on the sensitivity to each component color light,
Since the number of amplifiers and A / D converters is determined for each component color, the number of amplifiers and A / D converters can be reduced to a necessary minimum in addition to the above effects. .

According to a fourth aspect of the present invention, in the first aspect of the present invention, an amplifier and an A / D converter are provided for each component color, and the amount of incident light of each component color light on the reading sensor and the reading sensor Depending on the sensitivity to each component color light,
Since the gain of the amplifier is determined for each component color,
In addition to the above effects, there is the effect that high-gradation data that accurately represents the contents of the document can be obtained for each component color.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of a digital laboratory system according to an embodiment.

FIG. 2 is an external view of a digital laboratory system.

FIGS. 3A and 3B are schematic diagrams illustrating an example of a schematic configuration of an optical system of a line CCD scanner.

4A is a plan view showing an example of a turret; FIG. 4B is a plan view showing an example of a diaphragm; FIG.

FIG. 5 is a block diagram showing a schematic configuration of an electric system of the line CCD scanner.

FIG. 6 is a block diagram illustrating a schematic configuration of an image processing unit.

FIG. 7 is a flowchart illustrating a content of a reading condition calculation process executed by an auto setup engine of the image processing unit.

FIG. 8 is a flowchart showing the contents of a film image reading process executed by the microprocessor of the line CCD scanner.

[Explanation of symbols]

 14 Line CCD scanner 46 Microprocessor 97A, 97B Amplifier 98A, 98B A / D converter 99 Selector 116 Line CCD 144 Auto setup engine

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H04N 1/46 A F term (Reference) 5B047 AA05 AA27 AB04 BA02 BB02 BC07 BC18 CA06 CB15 DA01 DA06 DB01 DB04 5C062 AA01 AB03 AB17 AB22 AB32. HA08 HB01 HB02 HB12 JA02 JA04 JA16 JA23 JA28 KA02 KA09 KA17 KA18 KA20 LA10 LA23 LB01 MA02 MA17 NA03 NA04 NA29 PA03

Claims (4)

[Claims] 1. A reading sensor that receives light from a document and outputs a reading signal according to the amount of incident light; a plurality of amplifiers that amplify the reading signal output from the reading sensor with gains different from each other; A plurality of A / D converters respectively provided corresponding to the amplifiers and converting read signals amplified by the corresponding amplifiers into digital read data, respectively, and output from the plurality of A / D converters, respectively. A document reading device, comprising: selecting means for selecting one of a plurality of types of read data. 2. The method according to claim 1, wherein the original is a photographic film, and a plurality of film images recorded on the photographic film are preliminarily read based on each film image data. 2. The original reading apparatus according to claim 1, further comprising control means for controlling selection by said selection means when performing actual reading for each film image. 3. The reading sensor outputs a reading signal for each component color according to the amount of incident light of each component color light from the document. The amplifier and the A / D converter correspond to each component color. The number of amplifiers and A / D converters is determined for each component color in accordance with the amount of incident light of each component color light on the reading sensor and the sensitivity of the reading sensor to each component color light. 2. The document reading apparatus according to claim 1, wherein: 4. The reading sensor outputs a reading signal for each component color according to the amount of incident light of each component color light from a document, and the amplifier and the A / D converter correspond to each component color. The gain of the amplifier is determined for each component color in accordance with the amount of incident light of each component color light on the reading sensor and the sensitivity of the reading sensor to each component color light. Original reading device.