JP2001339581A - Image read method and device, and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image read method and device that can read a transparent original with a wide gray scale range such as a negative film at a high- speed with high accuracy. SOLUTION: A CPU 8 functions as a controller to revise a storage time of a CCD 4 during reading of an image recorded on a transparent original 2 by each line with respect to a read direction, to classify an image signal obtained from each line by the storage time when reading the line and to arrange each of the line data to acquire a plurality of image data and to store the respective image data to storage devices 6, 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image reading method and apparatus, and a storage medium storing a control program for controlling the image reading apparatus.

[0002]

2. Description of the Related Art Conventionally, in an image reading apparatus (scanner) for reading an image recorded on a film serving as a recording medium, in order to read a document at a high SN, a pre-scan is first performed at a low resolution and read. After roughly grasping the density range of the document, the brightness of the light source is adjusted to adjust the amount of light reaching the CCD so that the photoelectric conversion range of the CCD (image pickup device) serving as the reading means can be sufficiently used.
The image signal is adjusted to the dynamic range of the A / D converter by controlling the gain control amplifier with respect to the output signal. Furthermore, when the gain is insufficient with only the gain control amplifier, the adjustment is performed by controlling the shape of the LUT for converting the A / D converted digital signal. This is necessary especially for a document having a wide range such as a negative film.

In order to properly perform the setting for the main scan, first, the luminance level of the light source so that the CCD is not surely saturated during the pre-scan must be set in consideration of the transmission density of the document. No. But actually,
Since there are individual differences in the saturation voltage of the CCD or the optical system elements such as lenses and filters, the luminance of the light source is set to a sufficiently low level so that saturation does not occur with respect to the saturation of the CCD in consideration of such variations. Must be set to

[0004] However, in this case, when the sensitivity of the CCD is low or when the original has a high density such as an over-negative image, the information amount of the image data obtained by the prescan decreases. At this time, information indicating the characteristics of the document required for the main scan is reduced, leading to a decrease in the accuracy of the main scan.

In such a case, if the image signal is adjusted to the dynamic range of the A / D converter by electrically amplifying the signal using a gain control amplifier, noise included in the signal is also amplified. As a result, the SN ratio of the scanned image deteriorates.

Such a problem occurs because the transmission density range of an input document is very wide in the case of a negative film or the like with respect to the dynamic range of photoelectric conversion of a CCD.

In order to avoid the deterioration of the SN ratio due to the increase of the analog gain, a CCD using an optical filter is used.
A method of acquiring image data with a fixed gain by adjusting the amount of light reaching or changing the accumulation time of the CCD and performing scanning a plurality of times has been proposed (for example, Japanese Patent Application Laid-Open No. H11-88898).

[0008]

However, in the case of the conventional method in which an optical filter is provided and the filter is switched according to the amount of light reaching the CCD, the condition for switching the filter depends on information obtained by pre-scanning, and the In the case of a high original, the filter switching for the same original is not stable because the information obtained by the prescan is small, or the information is unstable because the information is electrically amplified and contains a lot of noise. In some cases, the actual scan image data becomes unstable as a result.

Further, in the conventional method in which scanning is performed a plurality of times by changing the accumulation time of the CCD, the overall throughput is reduced, and it is difficult to increase the speed. This is not suitable for a device that processes a large number of orders.

The present invention has been made in view of the above-mentioned problems of the prior art described above, and a first object of the present invention is to provide a transparent original having a wide density range such as a negative film. It is an object of the present invention to provide an image reading method and apparatus capable of high-speed and high-precision reading.

A second object of the present invention is to provide a storage medium storing a control program for controlling the above-described image reading apparatus of the present invention.

[0012]

According to a first aspect of the present invention, there is provided an image reading method for reading an image recorded on a recording medium by changing an accumulation time of the reading means in a reading direction. In contrast, an accumulation time change step that can be changed for each line, and image data acquisition that acquires a plurality of image data by classifying image signals obtained from each line according to the accumulation time of reading the line and collecting each line data And an independent storage step for storing respective image data.

According to a second aspect of the present invention, there is provided an image reading method according to the first aspect, wherein a plurality of accumulation times are sequentially applied to each line in the image reading method. A reading step of reading at the highest resolution, a histogram creating step of creating a histogram from each of a plurality of image data obtained by combining image signals from lines read at the same accumulation time, and a plurality of histograms obtained by the histogram creating step. A determining step of determining which image data has the most information recorded on the recording medium from the histogram; and selecting an image from a plurality of image data based on the determination result of the determining step, and finally outputting And a control step of performing control so as to obtain image data.

According to a third aspect of the present invention, there is provided an image reading method according to the first aspect, wherein two kinds of storage times are alternately applied to each line. Reading at the highest resolution, a histogram creating step of creating a histogram from each of two image data obtained by combining the image signals from the lines read at the same accumulation time, and 2 histograms obtained by the histogram creating step. A determination step of determining which image data has more information recorded on a recording medium from the statistical information of the two histograms; and one of the two image data based on the determination result of the determination step And selecting a final output image data and controlling the final output image data.

According to a fourth aspect of the present invention, there is provided an image reading method according to any one of the first to third aspects.
Image data selected from a plurality of image data obtained by using a plurality of accumulation times in order and determined by a histogram created from each image data is spatially thinned out and used to display an index. It is characterized by doing.

According to a fifth aspect of the present invention, there is provided an image reading method as set forth in any one of the first to third aspects.
1 if the optical resolution is lower than the actual reading resolution
Image data obtained alternately for each line is used as output image data as it is, and when the optical resolution is higher than the actual reading resolution, control is performed so as to perform spatial compensation by taking a moving average of two lines. It is characterized by.

According to a sixth aspect of the present invention, there is provided an image reading method according to the first aspect, wherein a plurality of storage times are sequentially applied for each line in the image reading method. A histogram is created from each of a plurality of image data obtained by combining image signals from lines having the same accumulation time with respect to image data obtained in a reading step of reading an image at a low resolution and the first reading in the reading step. A histogram creation step, a determination step of determining which image data has the most information recorded on the recording medium based on the statistical information of the histogram obtained in the histogram creation step, and a determination of the determination step A setting step of resetting predetermined items based on information obtained from a histogram of image data selected based on the result; Characterized by a control step of controlling so as to read a second time at a high resolution with the conditions set by the degree.

According to a seventh aspect of the present invention, there is provided an image reading method according to any one of the first to third and sixth aspects, wherein the recording medium is a film. It is characterized by being.

According to another aspect of the present invention, there is provided an image reading method, comprising the steps of:
6. The image reading method according to claim 6, wherein the reading unit is a CCD (image pickup device).

In order to achieve the first object, the image reading method according to the ninth aspect of the present invention is the image reading method according to the sixth aspect, wherein the predetermined items include an accumulation time, a light source light amount, and an analog light amount. It is characterized by gain.

According to another aspect of the present invention, there is provided an image reading apparatus, wherein the storage time of the reading means is read line by line with respect to the reading direction during reading of an image recorded on a recording medium. Storage time changing means that can be changed to, image data obtaining means for obtaining a plurality of image data by grouping each line data by classifying the image signal obtained from each line by the storage time of reading the line,
Independent memory means for accumulating respective image data is provided.

According to another aspect of the present invention, there is provided an image reading apparatus according to the present invention, wherein a plurality of storage times are sequentially set for each line at the highest resolution. A histogram creating means for creating a histogram from each of a plurality of image data obtained by combining the image signals from lines read at the same accumulation time by applying the image, and a plurality of histograms obtained by the histogram creating means Determining means for determining which image data has the largest amount of information recorded on the recording medium, and selecting an image from a plurality of pieces of image data based on a result of the determination by the determining means. And control means for controlling the data to be data.

In order to achieve the first object, the image reading apparatus according to the twelfth aspect of the present invention is the image reading apparatus according to the tenth aspect, wherein two types of storage time are alternately provided for each line at the highest resolution. A histogram creating means for creating a histogram from each of two image data obtained by combining the image signals from the lines read at the same accumulation time by applying Judging means for judging which image data has more information recorded on the recording medium from the statistical information of the histogram; and determining one of the two image data based on the judgment result of the judging means. And control means for controlling the selected output image data to be final output image data.

In order to achieve the first object, an image reading apparatus according to claim 13 is provided.
In the image reading device according to any one of the above, the control unit may select an image selected from a plurality of pieces of image data obtained by sequentially using a plurality of accumulation times by using a histogram created from each image data. Data is spatially thinned out and controlled so as to be used for index display.

In order to achieve the first object, an image reading apparatus according to claim 14 is provided.
In the image reading device according to any one of the above, when the optical resolution is lower than the actual reading resolution, the control unit may use the image data obtained alternately for each line as output image data as it is, and Is higher than the actual reading resolution, a control is performed so as to perform spatial compensation by taking a moving average of two lines.

According to a fifteenth aspect of the present invention, in the image reading apparatus according to the tenth aspect, a plurality of storage times are sequentially reduced for each line at a low resolution. A histogram creation unit for reading an image by applying the same and creating a histogram from each of a plurality of image data obtained by combining image signals from the same accumulation time with respect to image data obtained in the first reading by the reading unit; Determining means for determining which image data has the most information recorded on the recording medium based on the statistical information of the histogram obtained by the histogram creating means; and Setting means for resetting predetermined items based on information obtained from a histogram of image data selected by the user; Ri and having a control means for controlling so as to read a second time at a high resolution in the set condition.

In order to achieve the first object, an image reading apparatus according to claim 16 is provided.
The image reading device according to any one of Items 2 and 15, wherein the recording medium is a film.

In order to achieve the first object, an image reading apparatus according to claim 17 is provided.
16. The image reading device according to any one of 2, 14 and 15, wherein the reading unit is a CCD (image pickup device).

In order to achieve the first object, an image reading apparatus according to claim 18 is the image reading apparatus according to claim 15, wherein the predetermined items include an accumulation time,
It is characterized by a light source light quantity and an analog gain.

In order to achieve the second object, a storage medium according to a nineteenth aspect is a storage medium storing a control program for controlling an image reading device, wherein the control program is a recording medium. An accumulation time change module that can change the accumulation time of the reading means for each line in the reading direction while reading an image recorded on a medium, and classifies an image signal obtained from each line according to the accumulation time when the line is read. An image data acquisition module for acquiring a plurality of image data by collecting each line data,
And an independent storage module for storing each image data.

In order to achieve the second object, a storage medium according to claim 20 is the storage medium according to claim 19, wherein the control program is configured to sequentially store a plurality of storage times for each line. A reading module that applies and reads at the highest resolution, a histogram creation module that creates a histogram from each of a plurality of image data obtained by combining image signals from lines read at the same accumulation time, and a histogram creation module that is obtained by the histogram creation module. A judgment module for judging which image data has the most information recorded on the recording medium from the plurality of histograms, and selecting an image from the plurality of image data based on the judgment result of the judgment module. And a control module for controlling the output image data to be .

In order to achieve the second object, a storage medium according to claim 21 is the storage medium according to claim 19, wherein the control program alternates two types of storage time for each line. A reading module for reading at the highest resolution by applying to the above, a histogram creating module for creating a histogram from each of two image data obtained by combining image signals from lines read at the same accumulation time, and a histogram creating module A determination module that determines which image data has more information recorded on the recording medium from the obtained statistical information of the two histograms; and a determination module that determines which of the two image data based on the determination result of the determination module. A control module that selects one image and controls it to be the final output image data Characterized in that it has a.

In order to achieve the second object, the storage medium according to claim 22 is the storage medium according to any one of claims 19 to 21, wherein the control module is configured to store a plurality of storage times. The image data selected from the plurality of image data obtained in order and determined by the histogram created from the respective image data is spatially thinned out and controlled so as to be used for index display. I do.

In order to achieve the second object, the storage medium according to claim 23 is the storage medium according to any one of claims 19 to 21, wherein the control module has an optical resolution When the optical resolution is lower than the actual reading resolution, the image data obtained alternately for each line is used as it is as output image data. When the optical resolution is higher than the actual reading resolution, a moving average of two lines is calculated. It is characterized by performing control so as to perform dynamic compensation.

In order to achieve the second object, a storage medium according to a twenty-fourth aspect is the storage medium according to the nineteenth aspect, wherein the control program sequentially stores a plurality of storage times for each line. A reading module for applying an image at a low resolution by applying, and a histogram from each of a plurality of image data obtained by combining image signals from lines having the same accumulation time with respect to image data obtained in the first reading by the reading module. A determination module for determining which image data has the most information recorded on the recording medium based on the statistical information of the histogram obtained by the histogram generation module; and From the histogram of the image data selected based on the judgment result of the module. Information and setting module to be done to reset the predetermined items based on that, and having a control module for controlling so as to read a second time at a high resolution under the condition set by the setting module.

In order to achieve the second object, the storage medium according to the twenty-fifth aspect is provided with the storage medium according to the nineteenth to twenty-first and twenty-second aspects.
5. The storage medium according to claim 4, wherein the recording medium is a film.

In order to achieve the second object, the storage medium according to the twenty-sixth aspect provides the storage medium according to the nineteenth to twenty-first and twenty-second aspects.
25. The storage medium according to claim 3, wherein the reading unit is a CCD (image pickup device).

In order to achieve the second object, the storage medium according to claim 27 is the storage medium according to claim 24, wherein the predetermined items include an accumulation time, a light source light amount, and an analog gain. There is a feature.

In order to achieve the second object, a storage medium according to claim 28 is the storage medium according to any one of claims 19 to 27, wherein the storage medium is a floppy disk. It is characterized by.

In order to achieve the second object, the storage medium according to claim 29 is the storage medium according to any one of claims 19 to 27, wherein the storage medium is a hard disk. Features.

In order to achieve the second object, the storage medium according to claim 30 is the storage medium according to any one of claims 19 to 27, wherein the storage medium is an optical disk. Features.

In order to achieve the second object, a storage medium according to claim 31 is the storage medium according to any one of claims 19 to 27, wherein the storage medium is a magneto-optical disk. It is characterized by the following.

In order to achieve the second object, a storage medium according to claim 32 is a storage medium according to any one of claims 19 to 27, wherein the storage medium is a C medium.
D-ROM (Compact Disk Read O)
nly Memory).

In order to achieve the second object, the storage medium according to claim 33 is the storage medium according to any one of claims 19 to 27, wherein the storage medium is a C medium.
DR (Compact Disk Recordab)
le).

In order to achieve the second object, a storage medium according to claim 34 is the storage medium according to any one of claims 19 to 27, wherein the storage medium is a magnetic tape. It is characterized by.

In order to achieve the second object, a storage medium according to claim 35 is the storage medium according to any one of claims 19 to 27, wherein the storage medium is a non-volatile memory card. There is a feature. In order to achieve the second object, a storage medium according to claim 36 is the storage medium according to any one of claims 19 to 27, wherein the storage medium is a ROM (Read On).
ly memory) chip.

[0047]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) First, the first embodiment of the present invention will be described.
The embodiment will be described with reference to FIGS.

FIG. 1 is a block diagram showing a configuration of an image reading apparatus (scanner) according to the present embodiment. In FIG. 1, reference numeral 1 denotes a lamp (light source), 2 denotes a transparent original, 3 denotes a lens group, 4 denotes a CCD (imaging device) as reading means, and 5 denotes a signal processing unit which processes an image signal from the CCD 4. 6,
Reference numeral 7 denotes a storage device for storing image data from the signal processing unit 5. A CPU (Central Processing Unit) 8 controls the accumulation time of the CCD 4 and creates a histogram from the acquired image data, and has an accumulation time control unit and a histogram creation unit. Reference numeral 9 denotes a host PC (personal computer).

As a premise, the transparent original 2 is fed by driving means such as a motor, and an image is read at the highest resolution of the apparatus (scanner). The description will be made on the assumption that the resolution of the A / D converter is 10 bits and that the A / D converter exists inside the CPU 8.

The transmitted light from the lamp 1 that has passed through the transparent original 2 is condensed by the lens group 3 and photoelectrically converted by the CCD 4. At this time, the CPU 8 operates the CCD 4 while alternately changing the two predetermined storage times for each line, and photoelectrically converts the transmitted light from the transparent original 2.

Next, FIG. 1 shows the two types of accumulation time.
A description will be given with reference to FIGS.

It is to be noted that one of the two types of accumulation time t1 is used to read a document having a density lower than the proper exposure, that is, a document including a density near the negative base such as an underexposed negative film. Sometimes, the accumulation time is such that the CCD 4 does not saturate in relation to the brightness of the lamp 1 and the transmittance of the lens group 3, and the histogram created from the image data obtained at this time has an average distribution without bias. This is an accumulation time that is generated in a typical manner. The other accumulation time t2 is an accumulation time such that a histogram created from image data obtained when reading an overexposed high-density film is generated without bias in distribution.

Between these accumulation times t1 and t2,
It is assumed that the following relational expression (1) holds.

T2 = 2 × t1 (1) In the signal processor 5, the signal from the CCD 4 is electrically amplified and then A / D converted. The A / D-converted digital signal is divided into odd lines and even lines and formed as image data (see FIG. 2), and the image data obtained from the odd lines is stored in the odd line data storage device 6.
The image data obtained from the even-numbered lines are stored in the even-numbered-line data storage device 7 respectively. That is, two different image data are acquired by one scanning.

FIG. 2 is a conceptual diagram showing the relationship between the two types of accumulation times t1 and t2 and the histogram. FIG. 2A shows how the CCD 4 is changed while the accumulation times t1 and t2 are alternately changed line by line. FIG. 2B shows the line data acquired at the accumulation time t1, FIG. 2C shows the line data acquired at the accumulation time t2, and FIG.
Indicates a histogram created based on the line data acquired at the accumulation time t1, and FIG.
5 shows a histogram created based on the line data acquired in step (1).

Next, the CPU 8 creates a histogram from each of the two types of image data. For example, in the case of a transmission original in which the transmission density is distributed in the range of 0.6 to 1.6, the dynamic range is 1.0, that is, a change in the transmittance of 10 times, and this is a change of 102 to 1 on the histogram.
023 (see FIG. 3).
(A)). Since it is assumed that the CCD 4 is adjusted so as not to be saturated in the accumulation time t1, this histogram sufficiently represents image information of the document.

On the other hand, if the accumulation times t1 and t2 satisfy the above expression (1) and the gain of the gain control amplifier does not change, the histogram obtained from the image data acquired at the accumulation time t2 is approximately 204. ~ 1
023 (FIG. 3B).

However, at this time, the CCD 4 is in a saturated state, and it cannot be said that the image information recorded on the transparent original 2 is appropriately displayed on the histogram. This is determined from statistical values such as the average value and variance obtained from the histogram. Therefore, in this case, the accumulation time t
The image data acquired in step 1 is selected as the final output image data used for the application, and is transferred to the host PC 9.

In the case of an over-exposed negative film in which the transmission density is distributed from 1.2 to 2.2, the transmittance is similarly changed by a factor of 10 but the accumulation time t
In the image data acquired in step 1, the histogram
Image data is distributed in a range such as 257 (FIG. 4A). However, in the image data acquired at the accumulation time t2, the image data is distributed in a range of 52 to 514 (FIG. 4B), and it can be determined that the image data includes more image information recorded on the document than the former. In this case, the image data acquired at the accumulation time t2 is selected as the final output image data used for the application, and is transferred to the host PC 9.

The host PC 9 can use the image data obtained in this way as an index display by averaging four lines, etc., and at the same time, has already obtained the image data at the highest resolution of the scanner. Image data necessary for operations such as outputting to a printer or recording on another medium is acquired by one scanning.

If the optical resolution of the scanner is lower than the reading resolution, image data of every other line may be used as output image data as it is, and in the opposite case, a spatial compensation means for reading every other line is provided. Provide.
This can be achieved, for example, by a two-line moving average.

In the image reading apparatus according to the present embodiment, the functions of the above-described embodiment are realized by a computer reading and executing a control program stored in a storage medium. However, the present invention is not limited to this, and performs a part or all of actual processing such as an OS (Operating System) running on a computer based on an instruction of the control program, and performs the processing described above. It goes without saying that a case where the function of the present embodiment is realized is also included.

As a storage medium for storing the control program, for example, a floppy (registered trademark) disk,
Hard disk, optical disk, magneto-optical disk, CD-
ROM (Compact Disk Read Onl)
y Memory), CD-R (Compact Di)
sk Recordable), a magnetic tape, a nonvolatile memory card, a ROM chip, or the like.

As described in detail above, in the present embodiment, the CCD 4 is driven while setting a plurality of accumulation times for each line, and separate storage devices 6, 7 for each line acquired at different accumulation times. Is provided, a plurality of image data having different data distributions can be obtained at one time. This is equivalent to reading a document by changing the brightness of the lamp 1 or obtaining an image by switching an optical filter. However, all of these methods require at least two reading operations before and after changing the brightness of the lamp 1 or before and after switching the optical filter. In the present embodiment, however, the reading operation is performed by one reading. Have achieved.

Therefore, according to the present embodiment, the lamp 1
By setting an appropriate storage time in accordance with the luminance of the CCD 4, the sensitivity of the CCD 4, and the density range of the transparent original 2 to be read, information recorded on the original 2 can be obtained as image data by one reading. It is possible.

As a result, a one-pass scan can be performed without deteriorating the throughput due to the conventional image reading in the pre-scan and the main scan, and high-speed reading of a large number of documents can be performed.

Further, according to the present embodiment, when applied to a method of acquiring image data by two readings of pre-scan and main scan, the pre-scanning is performed as in the case of an over-exposed negative film. It is possible to prevent a reduction in the accuracy of the main scan due to an insufficient amount of information of the image.

(Second Embodiment) Next, a second embodiment of the present invention will be described.
An embodiment will be described. In the second embodiment, the first scanning is performed at a relatively low resolution and at a high speed. At this time, two kinds of accumulation times are prepared, and reading is performed alternately for each line. As a result, two image data having different brightness can be obtained as a prescan image. A histogram is created from each of these image data, and the one that statistically represents more information recorded on the document is selected. Based on the histogram, the setting for the main scan performed at the second high resolution is performed. This is, for example, the brightness of lamp 1,
These are the settings of the gain and LUT of the gain control amplifier.

The other configurations, operations, and effects of this embodiment are the same as those of the above-described first embodiment, and a description thereof will be omitted.

The storage device 6 for odd line data and the storage device 7 for even line data described above
In the case of obtaining image data that can be a final output image by one reading as in the embodiment, each of them must have a sufficient capacity.

On the other hand, in a system in which reading is performed twice and a final output image is obtained in the second reading as in the second embodiment, two image data obtained in the first reading are Since the resolution is low, the data amount is small. In this case, the two storage devices 6 and 7 can fulfill their role with a small capacity such as a memory.

The CCD signal processor, the gain control amplifier, and the A / D converter are provided inside the signal processing section 5, and the gain of the gain control amplifier can be controlled by the CPU 8. Also,
In the above-described embodiment, the accuracy of the A / D converter is set to 10 b
Although it has been described as it, it is obvious that by increasing the accuracy to 12 bits and 16 bits, the image quality of the output image can be improved in proportion thereto.

Further, it is assumed that the LUT exists inside the CPU 8 and the shape change control of the LUT is possible by the CPU 8.

[0075]

As described above in detail, according to the image reading method and apparatus of the present invention, an image can be read by performing high-resolution reading only once. In particular, when reading an image recorded on a recording medium (original) having a wide density range, for example, an image recorded on a negative film, the pre-scan is performed as in the related art, and the light amount is controlled in accordance with the density of the negative film. To do a scan,
It is not necessary to perform two reading operations, and it is possible to obtain image data that can be used practically. Therefore, an increase in the amount of noise due to an increase in the amplification factor can be avoided by fixing the amplification means, for example, a gain control amplifier or the like at an appropriate amplification factor and performing optimal design.

The present invention can also be applied to a method of acquiring image data by performing two scans, prescan and main scan. In this case, it is possible to stably obtain a prescan image containing sufficient information of the document regardless of the density of the document as the recording medium, so that various setting accuracy at the time of the main scan is improved, As a result, the main scan image can be stabilized.

Further, according to the storage medium of the present invention, the above-described image reading apparatus of the present invention can be smoothly controlled.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an image reading apparatus according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram illustrating a relationship between an accumulation time and a histogram in the image reading device according to the first embodiment of the present invention.

FIG. 3 shows an image reading apparatus according to a first embodiment of the present invention, in which a properly exposed negative film is stored for accumulation times t1, t.
FIG. 7 is a diagram illustrating an example of a histogram obtained when the image is acquired in FIG.

FIG. 4 shows an image reading apparatus according to a first embodiment of the present invention, in which an overexposed negative film is stored for an accumulation time t.
It is a figure showing an example of a histogram obtained when acquiring at 1, t2.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 lamp (light source) 2 transparent original (recording medium) 3 lens group 4 CCD (imaging element) 5 signal processing unit 6 storage device for odd-line data 7 storage device for even-line data 8 CPU (central processing unit) 9 host PC (personal computer)

Claims (36)

[Claims] An accumulation time changing step for changing the accumulation time of a reading means for each line in a reading direction during reading of an image recorded on a recording medium, and an image signal obtained from each line is converted to the line. An image characterized by having an image data obtaining step of obtaining a plurality of image data by classifying each line data according to the read storage time and an independent storage step of storing each image data Reading method. 2. A reading step in which a plurality of accumulation times are sequentially applied to each line to read at the highest resolution, and a histogram from each of a plurality of image data obtained by combining image signals from lines read in the same accumulation time. Creating a histogram, determining which image data has the most information recorded on the recording medium from the plurality of histograms obtained in the histogram creating step, and determining in the determining step 2. The image reading method according to claim 1, further comprising a control step of selecting an image from the plurality of image data based on the result and controlling the image data to be final output image data. 3. A reading step in which two kinds of accumulation times are alternately applied for each line to read at the highest resolution, and two image data obtained by combining image signals from lines read in the same accumulation time. A histogram creation step of creating a histogram; a determination step of determining which image data has more information recorded on a recording medium from statistical information of the two histograms obtained in the histogram creation step; 2. The control method according to claim 1, further comprising a control step of selecting one of the two image data based on a result of the determination in the determination step and controlling the selected image to be final output image data. Image reading method. 4. The control step spatially thins out image data selected by a judgment based on a histogram created from each image data among a plurality of image data obtained by sequentially using a plurality of accumulation times. 4. The image reading method according to claim 1, wherein the image reading method is controlled so as to be used for index display. 5. The control step according to claim 1, wherein, when the optical resolution is lower than the actual reading resolution, the image data obtained alternately for each line is used as output image data as it is, and the optical resolution is changed to the actual reading resolution. 4. The image reading method according to claim 1, wherein the control is performed such that spatial compensation is performed by taking a moving average of two lines when the moving average is higher. 6. A reading step of reading an image at a low resolution by sequentially applying a plurality of accumulation times for each line, and an image data obtained in a first reading by the reading step is performed from a line having the same accumulation time. A histogram creation step of creating a histogram from each of a plurality of image data obtained by combining image signals, and an image having the largest amount of information recorded on a recording medium based on the statistical information of the histogram obtained in the histogram creation step A determining step of determining which data is present; a setting step of resetting predetermined items based on information obtained from a histogram of image data selected based on the determination result of the determining step; And controlling the second reading at a high resolution under the conditions set by (1). The image reading method according to claim 1. 7. The image reading method according to claim 1, wherein the recording medium is a film. 8. The image reading method according to claim 1, wherein said reading means is a CCD (image pickup device). 9. The image reading method according to claim 6, wherein the predetermined items are an accumulation time, a light source light amount, and an analog gain. 10. An accumulation time changing means for changing an accumulation time of a reading means for each line in a reading direction during reading of an image recorded on a recording medium, and an image signal obtained from each line is converted to the line. An image, comprising: an image data acquisition unit that acquires a plurality of image data by classifying each line data according to a read accumulation time, and an independent storage unit that accumulates each image data. Reader. 11. An image is read by sequentially applying a plurality of accumulation times at the highest resolution for each line, and a histogram is formed from each of a plurality of image data obtained by combining image signals from lines read at the same accumulation time. Histogram creation means to be created, judgment means for judging which image data has the most information recorded on the recording medium from a plurality of histograms obtained by the histogram creation means, and judgment results of the judgment means 11. The image reading apparatus according to claim 10, further comprising: control means for selecting an image from a plurality of image data based on the image data and controlling the selected image data to be final output image data. 12. An image is read by alternately applying two types of storage times at the highest resolution for each line, and an image signal obtained from the lines read at the same storage time is obtained.
Histogram creation means for creating a histogram from each of the two image data, and determining which image data has more information recorded on the recording medium from the statistical information of the two histograms obtained by the histogram creation means And control means for selecting one of the two image data based on the judgment result of the judgment means and controlling the selected image data as final output image data. The image reading device according to claim 10. 13. The image processing apparatus according to claim 1, wherein the control unit spatially thins out image data selected from a plurality of image data obtained by sequentially using a plurality of accumulation times and determined by a histogram created from each image data. The image reading apparatus according to claim 10, wherein the image reading apparatus is controlled so as to be used for displaying an index. 14. When the optical resolution is lower than the actual reading resolution, the control means uses the image data obtained alternately for each line as output image data as it is, and sets the optical resolution to the actual reading resolution. 13. The image reading apparatus according to claim 10, wherein the control is performed so as to perform spatial compensation by taking a moving average of two lines when the moving average is higher. 15. An image is read by applying a plurality of storage times at low resolution in order for each line, and an image signal from a line having the same storage time is obtained for image data obtained in the first reading by the reading means. Histogram creating means for creating a histogram from each of a plurality of image data obtained in combination, and image data having the largest amount of information recorded on a recording medium based on the statistical information of the histogram obtained by the histogram creating means. Determining means for determining whether or not the information is obtained, setting means for resetting predetermined items based on information obtained from a histogram of image data selected based on the determination result of the determining means, And control means for controlling the second reading to be performed at a high resolution under the set conditions. 0. The image reading device according to 0. 16. The image reading apparatus according to claim 10, wherein the recording medium is a film. 17. The apparatus according to claim 17, wherein the reading unit is a CCD (image pickup device).
10. The method according to claim 10, wherein:
5. The image reading device according to any one of 5. 18. The apparatus according to claim 1, wherein the predetermined items are an accumulation time, a light source light amount, and an analog gain.
6. The image reading device according to 5. 19. A storage medium storing a control program for controlling an image reading apparatus, wherein the control program causes an accumulation time of a reading unit to be changed in a reading direction during reading of an image recorded on the recording medium. Storage time change module that can be changed for each line, and an image data acquisition module that obtains a plurality of image data by grouping each line data by classifying the image signals obtained from each line by the storage time of reading the line And an independent storage module for storing respective image data. 20. The control program, comprising: a reading module for sequentially applying a plurality of storage times for each line and reading at a highest resolution; and a plurality of images obtained by combining image signals from lines read at the same storage time. A histogram creation module that creates a histogram from each of the data, and a determination module that determines which image data has the most information recorded on the recording medium from the plurality of histograms obtained by the histogram creation module, 20. The storage medium according to claim 19, further comprising: a control module configured to select an image from a plurality of pieces of image data based on a determination result of the determination module and control the selected image data to be final output image data. 21. The control program according to claim 1, wherein the two kinds of accumulation times are alternately applied to each line to read the image at the highest resolution, and the read module acquires two image signals from the lines read at the same accumulation time. A histogram creation module for creating a histogram from each of the image data, and image data having more information recorded on a recording medium is determined from statistical information of the two histograms obtained by the histogram creation module. And a control module for selecting one of the two image data based on a result of the determination by the determination module and controlling the selected image to be final output image data. Item 20. The storage medium according to Item 19. 22. The control module spatially thins out image data selected from a plurality of image data obtained by using a plurality of accumulation times in order, based on a determination made by a histogram created from each image data. 22. The storage medium according to claim 19, wherein the storage medium is controlled so as to be used for index display. 23. When the optical resolution is lower than the actual reading resolution, the control module uses the image data obtained alternately for each line as output image data as it is, and sets the optical resolution to the actual reading resolution. 20. A control system for performing spatial compensation by taking a moving average of two lines when higher than the above.
2. The storage medium according to claim 1. 24. The control program, comprising: a reading module for reading an image at a low resolution by sequentially applying a plurality of storage times for each line; and a storage time for image data obtained in the first reading by the reading module. A histogram creation module for creating a histogram from each of a plurality of image data obtained by combining image signals from the same line; and information recorded on a recording medium based on statistical information of the histogram obtained by the histogram creation module. And a setting module for resetting predetermined items based on information obtained from a histogram of image data selected based on the determination result of the determination module. And the second time under the conditions set by the setting module 20. The storage medium according to claim 19, further comprising: a control module configured to perform reading at a high resolution. 25. The storage medium according to claim 19, wherein said recording medium is a film. 26. The reading means, comprising: a CCD (image pickup device)
20. The method according to claim 19, wherein:
4. The storage medium according to any one of 4. 27. The apparatus according to claim 24, wherein the predetermined items are an accumulation time, a light source light amount, and an analog gain.
A storage medium according to claim 1. 28. The storage medium according to claim 19, wherein said storage medium is a floppy disk. 29. The storage medium according to claim 19, wherein said storage medium is a hard disk. 30. The storage medium according to claim 19, wherein said storage medium is an optical disk. 31. The storage medium according to claim 19, wherein said storage medium is a magneto-optical disk. 32. The storage medium is a CD-ROM (Co-ROM).
mpact Disk Read Only Memo
28. The storage medium according to claim 19, wherein the storage medium is ry). 33. The storage medium has a CD-R (Comp
The storage medium according to any one of claims 19 to 27, wherein the storage medium is an act disk recordable. 34. The storage medium according to claim 19, wherein said storage medium is a magnetic tape. 35. The storage medium according to claim 19, wherein said storage medium is a nonvolatile memory card. 36. The storage medium, wherein the storage medium is a ROM (Read
The storage medium according to any one of claims 19 to 27, wherein the storage medium is an only memory (IC) chip.