JPH10276340A - Image input system, image input method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the image input system and the image input method in which an image with high quality is obtained, and to provide the storage medium storing a program to realize this method. SOLUTION: The operator receives a kind of a photo film 3 that is an original from an entry device 18. A matrix of a color correction section 12 is set depending on the setting of a filter changeover device 5 and a dimmer device 2 depending on the kind of the received photo film 3 and the transmittivity of the photo film 3 or the like. Thus, the image with high image quality is obtained by correcting color by taking the setting of optical means 1, 4 into account in addition to the kind of the photo film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image input device for converting an image on a document such as a film into an image signal that can be handled on a computer.

[0002]

2. Description of the Related Art Conventionally, there is an image input device for converting an image on a photographic film into an image signal. The light emitted from the light source projects an image on a film as an original onto a CCD through an optical lens and an optical filter. In the CCD, the projected image of the photographic film is converted into three RGB image signals by photoelectric conversion. Thereafter, the image signal is subjected to gradation correction by an LUT (conversion table) and color correction by primary conversion using a 3 × 3 matrix. LUT is a numerical value conversion method based on a correspondence table of output values to input values. The 3 × 3 matrix is switched according to the type of film.

For example, when reading a negative film,
An image signal can be obtained by removing the orange base, which is a feature of the negative film, with an optical filter for a negative film and inverting the gradation with an LUT.

[0004]

In the case of film input,
Image characteristics vary depending on the type of film and the setting conditions of the optical system. Particularly in the case of a negative film, the tendency of the negative base color characteristics differs depending on the type of the film. The color characteristics of the input image also vary depending on the brightness of the light source, which is the setting of the optical system, and the presence or absence of a filter.

In the conventional method, color correction is performed in consideration of the type of film, but color correction is not performed in consideration of the setting conditions of the optical system. Therefore, sufficient color correction could not be performed, and a high-quality image could not be obtained.

The present invention has been made under such circumstances, and an image input system capable of obtaining high-quality images,
It is an object of the present invention to provide an image input method and a storage medium.

[0007]

In order to achieve the above object, according to the present invention, an image input system includes the following (1) to (5).
As in (7), the image input method is configured as in (8), and the storage medium is configured as in (9).

(1) An image input system for capturing an image of a document by an optical means, converting the image into an electric signal, and correcting the color by a color correcting means, wherein the document type obtaining means for obtaining the type of the document, An image input system comprising: a control unit configured to control settings of the color correction unit according to a type of a document acquired by a type acquisition unit and settings of the optical unit.

(2) The image input system according to (1), wherein the setting of the optical means is a setting for enabling or disabling the optical filter.

(3) The image input system according to (1), wherein the setting of the optical means is a setting of a light amount level of the light source lamp.

(4) The image input system according to the above (1), wherein the setting of the optical means is setting of validity / invalidity of the optical filter and setting of the light amount level of the light source lamp.

(5) The image input system according to (1), wherein the setting of the color correction means is a setting of a matrix for color correction.

(6) The image input system according to any one of (1) to (5), wherein the document type obtaining means is a manual input device.

(7) The image input system according to any one of (1) to (5), wherein the document type obtaining means is a document type reading device.

(8) An image input method in an image input system in which an image of a document is captured by an optical means, converted into an electric signal, and color-corrected by a color correction means, wherein a step of acquiring the type of the document is provided. Controlling the setting of the color correcting means according to the type of the document acquired in step and the setting of the optical means.

(9) A storage medium storing a program for realizing the image input method according to (8).

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to embodiments of a film scanner system. The present invention is not limited to reading an image from a transparent document as in the embodiment, but can be similarly implemented in a form of reading an image from a reflective document. Further, the present invention is not limited to the image input system, and may be implemented in the form of an image input method and in the form of a storage medium storing a program for realizing the image input method.

[0018]

【Example】

(Embodiment 1) FIG. 1 is a block diagram showing a configuration of a "film scanner system" which is Embodiment 1. In FIG. 1, reference numeral 1 denotes a light source, and reference numeral 2 denotes a light amount (light intensity) of the light source 1.
It is a light control device that changes. Reference numeral 3 denotes a photographic film as an original, which moves in a direction perpendicular to the optical axis for scanning (scanning) by a mechanism (not shown).

Reference numeral 4 denotes a filter unit in which an ND filter for adjusting the amount of light reaching the CCD and a negative base removing filter inserted when scanning a negative film are incorporated. In the following, the negative base removing filter is replaced with filters I and N.
Let D filter be Filter II. 5 is a filter switching device. Reference numeral 6 denotes a lens group for condensing the transmitted light from the document 3, and reference numeral 7 denotes a CCD (line sensor) for converting the transmitted light from the lens group 6 to an electric signal.

Reference numeral 8 denotes an analog circuit for adjusting an electric signal obtained by the CCD 7, reference numeral 9 denotes an A / D converter,
Reference numeral 0 denotes a digital signal conversion table for converting a digital signal, reference numeral 11 denotes an LUT setting device for setting a table value, reference numeral 12 denotes a color correction unit for performing color adjustment using a color conversion matrix, and reference numeral 13 denotes a matrix value. A matrix setting device 14 is an image compression device that compresses the main scan image.

Reference numeral 15 denotes a storage device for storing a pre-scanned image, 16 denotes a storage device for storing a main-scanned image, 17 denotes a CPU for controlling each section, and 18 denotes a user's scanner. Reference numeral 19 denotes an input device for inputting instructions and setting of scanning conditions such as the type of film to be scanned, such as a display of a scanned image, a display of scanning condition settings instructed by a user, and a display of an input result of the user. Device.

Next, the flow of the scanning process will be described with reference to FIGS. FIG. 2 is a flowchart of the scanning process.

In step 201, the user operates the display device 1
Referring to the film type selection menu displayed in 9, the input device 18 is used to input the type of film to be scanned. In response, the host instructs the scanner to set prescan conditions. In step 205, the scanner sets the dimming device 2, the filter switching device 5, the gain in the analog system 8, the LUT setting device 11, and the matrix setting device 13 in accordance with the prescan condition setting from the host. In step 206, prescan is performed by the light source 1, the filter unit 4, the analog system 8, the digital signal conversion table 10, and the color correction unit 12 for which prescan conditions have been set.

The prescan processing is performed as follows. The light from the light source 1 is converted into an analog signal through the document 3, the filter unit 4, and the analog system 8, and the analog signal is A / A
The digital signal is converted into a digital signal by the D conversion device 9, the table is converted by the digital signal conversion table 10, and the color is corrected by the color correction unit 12, so that a prescan image is obtained. The pre-scan image has a lower resolution than the main scan. In step 202, the pre-scan image obtained from the scanner is stored in the pre-scan image storage device 15 of the host.

In step 203, the image characteristics are determined from the pre-scanned image, and the setting of the main scanning condition is instructed. Image characteristics are determined from features such as a film average density and density distribution by creating a histogram from the prescanned image. In step 207, the scanner sets the dimming device 2, the filter switching device 5, the gain in the analog system 8, the LUT setting device 11, and the matrix setting device 13 in accordance with the main scan condition setting from the host. In step 208, the main scan is performed by the light source 1, the filter unit 4, the analog system 8, the digital signal conversion table 10, and the color correction unit 12 for which the main scan conditions are set.

The main scan is performed in the same procedure as the pre-scan. The light from the light source 1 is converted into an analog signal through a document 3, a filter unit 4, and an analog system 8, and the analog signal is converted into a digital signal in an A / D converter 9, and is converted into a table by a digital signal conversion table 10, and a color correction unit. The main scan image is obtained by color adjustment in step S12. Thereafter, the main scan image is transferred to the image compression device 1.
It is compressed at 4 and sent to the host. At step 204,
The main scan image obtained from the scan is stored in the main scan image storage device 16 of the host and displayed on the display device 19.

Next, the flow of the scan condition setting is shown in FIG.
This will be described with reference to the flowchart of FIG. In step 301, the type of film to be scanned is input. In step 302, the flow is switched to step 303 if the film is a negative film, or to step 304 if the film is a positive film. In step 303, the negative filter I is enabled. The filter I is a negative base removing filter for removing the orange base of the negative film. In step 304, the negative filter I is invalidated.

In step 305, the processing flow is switched according to the density of the negative orange base. The film types are registered in advance as being divided into three base densities, "dark", "medium" and "light". For the type of film that has not been registered, the process proceeds to “intermediate” density.

In step 306, scan conditions are set for the negative film base density "dark". As shown in Table 1 below, light source settings, filter I and II settings, G
ain setting and LUT selection. The light source setting adjusts the brightness of the light source so as not to saturate the CCD 7 in accordance with the transmittance of the film original, and is set as a percentage with respect to the reference brightness. Filter II is set when adjusting the light source is not enough. Gain is an amplification amount for amplifying a signal from the CCD 7. In the case of the negative, the amplification amount needs to be adjusted because the density range of the image on the film is narrow. The LUT corrects the gradation of the image. In the case of a negative, negative / positive inversion is also performed by the LUT. (A) of FIG.
(B) and (c) show examples of the LUT.

[0030]

[Table 1]

In step 307, scan conditions are set for the negative film base density "intermediate". As shown in Table 1 above, light source settings, filter I and II settings, G
ain setting and LUT selection. In step 308, scanning conditions are set for the negative film base density "light". As shown in Table 1, light source setting, filter I and II setting, gain setting, and LUT selection are performed. In step 309, scanning conditions are set for the positive film. As shown in Table 1, light source setting, filter I and II setting, gain setting, and LUT selection are performed.

In step 310, a color correction parameter corresponding to the type of film and the scanner condition setting is searched. Step 3 if there is a corresponding color correction parameter
If the corresponding color correction parameter does not exist in step 11, the process proceeds to step 312. In step 311, a corresponding color correction parameter is set. In step 312, a default color correction parameter is set.

Scan conditions are set by the above flow.

Next, the color correction parameters will be described.
When correcting the input signal (RGB) to (R'G'B '), color correction is performed by the following linear conversion equation.

R ′ = a11R + a12G + a13B G ′ = a21R + a22G + a23B (1) B ′ = a31R + a32G + a33B The 3 × 3 matrix which is this parameter set is , And the state of the scan condition is n (n = 1, 2, 3,...)
..) And the 3 × 3 matrix αn (n = 1, 2, 3,...) Corresponding to the film types A, B, C, and D, the light amount of the light source that is the scanning condition, and the type of filter. 2. These 3 × 3 matrices αn are set with values optimized under the respective scanning conditions, prepared in advance in the host computer, and used by the CPU 17 in steps 201 and 203 by the CPU 17.
Is selected and transferred to the matrix setting device 13 on the scanner side.

[0036]

[Table 2]

For example, with a certain positive film, the light amount is 90,
Parameter set when Filter II is enabled The parameter set when the light intensity is 80 and Filter II is effective for a certain negative film is It is. If the negative orange base is a dark film,
Set the numerical value to suppress the B component.

By providing a 3 × 3 matrix for color correction on the host computer side, it is possible to add a 3 × 3 matrix by adding a corresponding film type and to change the value of the 3 × 3 matrix without changing the scanner body. Changes can be made easily.

(Embodiment 2) FIG. 5 is a diagram showing a configuration of a "film scanner system" which is Embodiment 2. As shown in the figure, the present embodiment has a configuration in which a film information reader 20 is added to the film scanner system of the first embodiment. The scanning process of the present embodiment will be described with reference to the flowchart of FIG.

In the flowchart of the scanning process shown in FIG. 2, in step 201, the film information recorded in the form of a code (bar code or magnetic code) at a predetermined position of the film shown in FIG.
Read at 0 and enter the type of film to scan. In response, the host instructs the scanner to set prescan conditions. The film information may be mechanical means such as providing a cut on the film.

By changing the configuration in this manner, the same effect as in the first embodiment can be obtained. In addition, since the film type information is generated from the original film, it is not necessary for the user to specify the film type information.
Film scanning work can be simplified.

In the first and second embodiments, the 3 × 3 matrix αn for color correction is prepared in the matrix setting device 13 on the scanner side, and is selected according to the type of film from the host and the setting of scanning conditions. A configuration may be used.

[0043]

As described above, according to the present invention,
By acquiring the type of original and controlling the setting of the color corrector based on the type of the original and the setting of the optical unit, sufficient color correction can be performed in consideration of the type of the original and the setting of the optical unit. Image is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a first embodiment.

FIG. 2 is a flowchart showing a scanning process.

FIG. 3 is a flowchart showing a scan condition setting process.

FIG. 4 is a diagram showing an example of an LUT.

FIG. 5 is a block diagram illustrating a configuration of a second embodiment.

FIG. 6 shows a film on which film information is recorded.

[Explanation of symbols]

 Reference Signs List 1 light source 3 document 4 filter unit 12 color correction unit 17 CPU

Claims (9)

[Claims] 1. An image of a document is captured by optical means,
An image input system that converts the signal into an electric signal and performs color correction by a color correction unit. The document type acquisition unit acquires the type of the document, and sets the type of the document acquired by the document type acquisition unit and the optical unit. And a control means for controlling the setting of the color correction means in accordance with the image input system. 2. The image input system according to claim 1, wherein the setting of the optical means is a setting for enabling or disabling the optical filter. 3. The image input system according to claim 1, wherein the setting of the optical means is a setting of a light amount level of a light source lamp. 4. The image input system according to claim 1, wherein the setting of the optical means includes setting of validity / invalidity of an optical filter and setting of a light amount level of a light source lamp. 5. The image input system according to claim 1, wherein the setting of the color correction means is a setting of a matrix for color correction. 6. The image input system according to claim 1, wherein the document type obtaining unit is a manual input device. 7. The image input system according to claim 1, wherein the document type obtaining means is a document type reading device. 8. An image of a document is captured by optical means,
An image input method in an image input system for converting an electric signal into an electric signal and performing color correction by a color correction unit, wherein the step of obtaining the type of the original is performed according to the type of the original obtained in this step and the setting of the optical unit. Controlling the setting of the color correcting means by using the image input method. 9. A storage medium storing a program for realizing the image input method according to claim 8.