JP2005073200A - Defective pixel correction apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To appropriately correct defective pixel data in a number of pixel data wherein pixel data characteristics or pixel sensor characteristics may be different. <P>SOLUTION: In a staggered arrangement CCD 27, two lines of a number of pixel sensors are arranged in a staggered manner, electric charges are outputted from the first line of pixel sensors 7A via a first output path, and electric charges are outputted from the second line of pixel sensors via a second output path. A defective pixel correction circuit 3 uses two pieces of pixel data, the two pieces of pixel data being just close to defective pixel data, via the same output path as the defective pixel data to correct the defective pixel data. Otherwise, the defective pixel correction circuit 3 uses two pieces of pixel data, the two pieces of pixel data being just close to defective pixel data, being located in the same line as a pixel sensor that outputs the defective pixel data, and being outputted from both left and right neighboring pixel sensors of said pixel sensor to correct the defective pixel data. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a technique for correcting defective pixels, for example, a technique for correcting defective pixel data output from a linear CCD mounted on an image scanner.

  As a technique of this type, for example, a method of correcting defective pixel data output from a CCD mounted on a television camera or the like based on surrounding pixel data adjacent thereto is known.

JP 2002-271806 A (paragraph 19)

  By the way, the CCD mounted on the image scanner includes a linear CCD that is long in the main scanning direction perpendicular to the sub-scanning direction. The linear CCD outputs pixel data corresponding to the amount of received light for each color. Some pixel sensors are arranged in a staggered pattern in two rows.

  In such a CCD (hereinafter referred to as “staggered CCD”), so-called double-sided reading is generally performed. Specifically, for example, a first transfer channel for transferring a signal charge shifted by a first CCD shift register that shifts a charge of a pixel sensor belonging to the first column, and a pixel sensor belonging to the second column And a second transfer channel for transferring the signal charge shifted by the second CCD shift register for shifting the charge. In this case, the pixel data obtained is different depending on the characteristics of the first and second transfer channels, or the characteristics of each device (for example, an operational amplifier) that converts the signal charge via each transfer channel into a voltage signal. Pixel data characteristics (for example, linearity representing the relationship between each pixel sensor and its output pixel data when the same amount of light is applied to the CCD) are often different. For this reason, pixel data adjacent to each target pixel data in a large number of pixel data output from the staggered CCD may be pixel data based on different pixel data characteristics.

  In addition, even if the same amount of light is irradiated to the pixel sensors in each color column on the staggered CCD, the pixel data output from the pixel sensors belonging to the first column and the second column adjacent to the first column are displayed. The pixel data output from the pixel sensor to which the pixel sensor belongs is a pixel sensor characteristic relating to the output of the pixel sensor for each column (for example, the amount of received light and the output pixel) due to the physical distance between the first column and the second column. The linearity (representing the relationship with the data) may be different. Therefore, in the image data output from the staggered CCD, the pixel sensor characteristics may be different between each pixel data and pixel data adjacent to the periphery thereof.

  In such cases, the conventional defective pixel correction method described above, that is, a method of correcting defective pixels using data of surrounding pixels adjacent to the defective pixels, the image data output from the staggered CCD is included in the image data. Even if defective pixel data is corrected, correction is performed using pixel data based on pixel data characteristics or pixel sensor characteristics that are different from the defective pixel data, so that defective pixel data is not necessarily corrected appropriately. Not exclusively.

  Such a problem is not limited to correcting defective pixel data in a large number of pixel data output from a staggered CCD, but defective pixel data in a large number of pixel data whose pixel data characteristics or pixel sensor characteristics may be different. There may also be other cases of correcting for.

  Accordingly, an object of the present invention is to appropriately correct defective pixel data in a large number of pixel data whose pixel data characteristics or pixel sensor characteristics may be different.

  The defective pixel correction device (hereinafter referred to as “first correction device”) according to the first aspect of the present invention may be included in pixel raster data having a large number of pixel data output from an image sensor that has received light. An apparatus for correcting defective pixel data, wherein the image sensor includes a plurality of pixel sensors that output pixel data corresponding to the amount of received light in a row, and the first pixel sensor among the plurality of pixel sensors. Pixel data is output from the group via a first output path, and pixel data is output from the second pixel sensor group via a second output path. The pixel data adjacent to each target pixel data in the pixel raster data in the column direction is pixel data output via an output path different from the output path through which the target pixel data passes, When defective pixel data is included in the pixel raster data, based on pixel data output from the same pixel sensor group as the pixel sensor group that has output the defective pixel data out of the pixel data constituting the raster data ( In other words, the defective pixel data is corrected based on, for example, pixel data output via the same output path as the defective pixel data.

  The image sensor is, for example, a linear CCD, and the pixel sensor is a photodiode. In addition, a large number of pixel sensors may be arranged in one or a plurality of columns. Further, the first correction device may be provided with defective pixel grasping means for grasping which defective pixel data is determined by a predetermined method. The defective pixel grasping means reads out defective pixel position information from, for example, a storage device provided in the first correction device, and from the defective pixel position information, which of the many pixel data constituting the pixel raster data is defective Know if it is pixel data.

  In a preferred embodiment of the first correction device, the first correction device is the pixel data output from the same pixel sensor group as the pixel sensor group that output the defective pixel data, and is closest to the defective pixel data. Based on a plurality of pixel data (in other words, for example, pixel data output via the same output path as the output path through which the defective pixel data passes, The defective pixel data is corrected (based on a plurality of pixel data nearest in the column direction).

  The defective pixel correction device (hereinafter referred to as “second correction device”) according to the second aspect of the present invention may be included in pixel raster data having a large number of pixel data output from an image sensor that has received light. An apparatus for correcting defective pixel data, wherein the image sensor includes a plurality of pixel sensors that output pixel data corresponding to the amount of received light in a row, and the first pixel sensor among the plurality of pixel sensors. The group constitutes a first pixel sensor column, the second pixel sensor group constitutes a second pixel sensor column, and is adjacent to each target pixel data in the pixel raster data in the column direction. Pixel data is pixel data output from a pixel sensor group that forms a different column from the pixel sensor group that output the target pixel data, and defective pixel data is included in predetermined pixel raster data. In some cases, the defective pixel data is corrected based on pixel data output from the same pixel sensor group as the pixel sensor group that output the defective pixel data among the pixel data constituting the raster data (another In other words, for example, the defective pixel data is corrected based on pixel data output from another pixel sensor included in the same pixel sensor group as the pixel sensor group including the pixel sensor that output the defective pixel data. To do).

  The image sensor is, for example, a linear CCD, and the pixel sensor is a photodiode. Further, the second correction device may be provided with defective pixel grasping means for grasping which defective pixel data is determined by a predetermined method. For example, the defective pixel grasping means reads out defective pixel position information from a storage device provided in the second correction device, and from the defective pixel position information, which of the many pixel data constituting the pixel raster data is defective. Know if it is pixel data.

  In a preferred embodiment of the second correction device, the second correction device is a pixel data output from the same pixel sensor group as the pixel sensor group that output the defective pixel data, and is closest to the defective pixel data. Based on a plurality of pixel data, the defective pixel data is corrected (for example, based on two pixel data output from pixel sensors existing on both sides in the same column as the pixel sensor that output the defective pixel data, The defective pixel data is corrected).

  In a preferred embodiment of at least one of the first and second correction devices, the multiple pixel sensors are arranged in a staggered manner on the image sensor.

  At least one of the first and second correction devices described above can be mounted on an image input device such as an image scanner, a digital camera, or a copying apparatus.

  Further, at least one of the first and second correction devices described above can be configured by only a hardware device, only software, or a combination of the hardware device and software. Further, when configured by software, for example, the first or second correction device (strictly, a computer program for constructing the correction device) is an image input device such as an image scanner or a digital camera, or the image input device. Installed on a higher-level device (for example, a general-purpose computer such as a personal computer) or the like, whereby the first or second correction device can be constructed on the installed device.

  According to the first correction device according to the first aspect of the present invention, correction of defective pixel data in pixel raster data is performed by pixels output from the same pixel sensor group as the pixel sensor group that output the defective pixel data. This is based on data, that is, pixel data that has passed through the same output path as the output path through which the defective pixel data has passed. Therefore, pixel data characteristics regarding each pixel data obtained through each output path (for example, a relationship between the position of each pixel sensor and its pixel data when the same amount of light is irradiated onto the CCD) Even if the linearity is different, the defective pixel correction data is corrected based on pixel data that has passed through the same output path, that is, pixel data that can have the same pixel data characteristics. Data can be corrected.

  According to the second correction device according to the second aspect of the present invention, correction of defective pixel data in pixel raster data is performed from pixel sensor groups that form the same column as the pixel sensor group that output the defective pixel correction data. This is performed based on the output pixel data. For this reason, even if the pixel sensor characteristics relating to the output of the pixel sensor for each column (for example, linearity representing the relationship between the amount of received light and the output pixel data) may be different, the defective pixel correction data is output as such. Corrected based on pixel data output from another pixel sensor belonging to the same pixel sensor group as the pixel sensor group including the selected pixel sensor, that is, pixel data that can have the same pixel sensor characteristics. Pixel data can be corrected.

  The present invention can be applied to various devices in which a large number of pixel data whose pixel data characteristics or pixel sensor characteristics may be different are output from the image sensor. Hereinafter, the image sensor is a “staggered CCD”. A case where the apparatus is an “image scanner” will be described as an example, and an embodiment of the present invention will be described with reference to the drawings.

  First, the outline of the image scanner according to the first embodiment of the present invention will be described with reference to FIG. 1, and then the defective pixel correction technique which is the gist of the present embodiment will be described with reference to FIG. .

  FIG. 1 is a block diagram showing a configuration of an image scanner according to an embodiment of the present invention.

  The image scanner 1 includes a reading head 5, a CCD substrate 15, a head drive mechanism 38, a pixel data memory (for example, RAM) 42, a defective pixel memory (for example, EEPROM) 44, a light source power source 35, and a control. A unit 45, a defective pixel correction circuit 3, a read image storage memory 46, and a read image output unit 43 are provided.

  The reading head 5 includes a light source 23, a staggered CCD 27 that receives reflected light or transmitted light from the light source 23 and outputs a signal charge corresponding to the received light amount, and a signal charge output from the staggered CCD 27 as a voltage signal. And a signal conversion unit 29 that converts the signal and outputs it to the A / D conversion circuit 31.

  The CCD substrate 15 is a circuit substrate that processes a voltage signal output from the staggered CCD 27 in the reading head 5 via the signal conversion unit 29, and includes a CCD power supply 33 and an A / D conversion circuit 31. . The CCD power supply 33 is turned on or off based on a control signal from the control unit 45. By turning on the CCD power supply 33, power supplied from a power supply circuit (not shown) is supplied to the staggered CCD 27, By turning off, power supply to the staggered CCD 27 is stopped. The A / D conversion circuit 31 receives an analog voltage signal output from the pixel sensor on the staggered CCD 27, converts it into a digital voltage signal, and stores the digital voltage signal, that is, pixel data in the memory 42. It has become.

  The head drive mechanism 38 is, for example, a belt for running the read head 5 along a shaft (not shown), a head drive motor for running the read head 5 by moving the belt, and driving the motor. And a head driving circuit for causing the reading head 5 to travel. A predetermined component (for example, a head drive circuit) of the head drive mechanism 38 receives a control signal from the control unit 45, and runs the read head 5 and controls its position based on the control signal.

  In the pixel data memory 42, read data for one line of a document to be read, that is, pixel raster data for each color (or pixel raster data arranged in the sub-scanning direction) in which a plurality of pixel data are arranged in a line. Original image data (each color plane)) is stored.

  The defective pixel memory 44 stores information (hereinafter referred to as “defective pixel position information”) for specifying the position of data of defective pixels detected by a predetermined defective pixel detection method. Various methods can be adopted as the defective pixel detection method. For example, the control unit 45 reads the pixel raster data from the pixel data memory 42 in which the pixel raster data is stored by reading the test pattern. Pixel data having a value different from a predetermined value or more among a plurality of pixel data included in the pixel raster data (in other words, a value more than a predetermined value due to a linear relationship between the position of each pixel sensor and the pixel data value from the pixel sensor) It is possible to employ a method of detecting pixel data that is out of order as defective pixel data. In this case, for example, the address of the defective pixel data is stored in the defective pixel memory 44 by the control unit 45.

  The light source power source 35 is turned on or turned off based on a control signal from the control unit 45. When the light source power source 35 is turned on, power supplied from a power supply circuit (not shown) is supplied to the light source 23 and turned off. As a result, the power supply to the light source 23 is stopped.

  A control unit (for example, CPU) 45 controls the entire operation of the image scanner 1.

  Specifically, for example, the control unit 45 inputs a clock having a predetermined cycle to a timing generator (not shown) so that a voltage signal is output from the staggered CCD 27 via the signal conversion unit 29 as a timing generator. To.

  For example, the control unit 45 inputs a correction command signal to the defective pixel correction circuit 3 and causes the defective pixel correction circuit 3 to execute a defective pixel correction process.

  The defective pixel correction circuit 3 is a pure hardware circuit such as an ASIC, for example, and starts a defective pixel correction process in response to a correction command signal from the control unit 45. Specifically, for example, the defective pixel correction circuit 3 reads out pixel raster data (or document image data) of each color from the pixel data memory 42, reads out defective pixel position information from the defective pixel memory 44, and detects the defective pixel. Based on the position information, defective pixel data is specified from a plurality of pixel data included in the read pixel raster data. The defective pixel correction circuit 3 is based on pixel data output via the same transfer channel as the defective pixel data (or pixel data output from a pixel sensor belonging to the same column as the defective pixel data). Then, the defective pixel data is corrected, and pixel raster data in which the defective pixel data is corrected (that is, corrected pixel raster data) is stored in the read image storage memory 46.

  The read image storage memory (for example, RAM or EEPROM) 46 stores corrected pixel raster data (or document image data). Thus, the read image storage memory 46 stores the corrected document read image data.

The read image output unit 43 reads corrected document read image data from the read image storage memory 46 and outputs it. Specifically, the read image output unit 43 includes, for example, the following (1) to (5),
(1) a data transmission unit for transmitting read image data by wire or wireless to a host device communicably connected to the image scanner 1;
(2) a data transmission unit that transmits read image data, for example, by e-mail to a remote device communicably connected to the image scanner 1 via a communication network such as the Internet;
(3) a facsimile transmission unit that transmits the read image data to a predetermined destination or a desired destination by facsimile via a public telephone network;
(4) a data storage unit for storing read image data in an external storage device (for example, a portable recording medium such as a memory card or an external hard disk device) detachably attached to the image scanner 1;
(5) A printing unit that prints the read image data on a predetermined print medium (for example, plain paper or glossy paper) by an inkjet method or an electrophotographic method,
At least one of them.

  FIG. 2 is a schematic diagram of the configuration of the staggered CCD 27.

  In the staggered CCD 27, a large number of pixel sensors (for example, photodiodes) are arranged in a staggered pattern in the main scanning direction for each color of RGB on a light receiving surface that receives reflected light or transmitted light from the light source 23. .

  Since the arrangement of the pixel sensors for each of the RGB colors is the same, R (red) will be described as a representative example. Among the multiple pixel sensors for R, the plurality of first pixel sensors 7A, 7A,. Are arranged in the main scanning direction, and the plurality of second pixel sensors 7B, 7B,... Are arranged in the main scanning direction along the second column.

  In the first column, the interval between each first pixel sensor 7A and the adjacent first pixel sensor 7A is a first distance, for example, 1600 dpi. Further, the distance along the sub-scanning direction between the pixel sensor 7A in the first column and the pixel sensor 7B in the second column is a second distance that is longer than the first distance, for example, 800 dpi. Furthermore, the pixel sensor 7B in the second row in the first color (for example, R) and the pixel sensor in the first column in the second color (for example, G) adjacent to the first color along the sub-scanning direction. The interval is a distance several times the second distance, for example, 5 times 160 dpi.

  As for a large number of R pixel sensors, a plurality of first pixel sensors 7A, 7A,... Are connected to the first signal converter 29 through a first output path 71 as shown in FIGS. The charge is transferred to the charge / voltage conversion device 29A, and the second charge / voltage conversion of the signal conversion unit 29 is similarly performed from the plurality of second pixel sensors 7B, 7B,. Charge is transferred to device 29B. Each of the output paths 71 and 73 includes, for example, a transfer channel to the charge / voltage conversion devices 29A and 29B and a shift register that transfers charges from each pixel sensor via the transfer channel. The charge-voltage conversion devices 29A and 29B (for example, operational amplifiers) convert transferred charges into analog voltage signals and transfer them to the A / D conversion circuit 31 (see FIG. 1).

  Under the configuration as described above, signal charges output from a large number of pixel sensors on the staggered CCD 27 are converted into digital voltage signals via a signal conversion unit 29 and an A / D conversion circuit 31 as shown in FIG. That is, pixel data is stored in the pixel data memory 42.

  As described above, the control unit 45 outputs signal charges from a large number of pixel sensors on the staggered CCD 27 via a timing generator (not shown). Depending on the reading resolution designated by the user, (The resolution is specified via a control panel (not shown) mounted on the image scanner 1 or a host device connected to the image scanner 1).

  For example, when the first resolution (3200 dpi as an example) is specified and the document reading image data of that resolution is generated, the control unit 45 outputs signal charges from all the pixel sensors on the staggered CCD 27. As a result, one pixel raster data stored in the pixel data memory 42 includes the first pixel data 100A obtained via the first output path 71 and the second output path as shown in FIG. The second pixel data 100B obtained via 73 is raster data 100 alternately arranged.

  In this case, for example, when the defective pixel data is one second pixel data via the second output path 73, the defective pixel correction circuit 3 performs the correction process of the defective pixel data as follows. Do.

  That is, as shown in FIG. 5, the defective pixel correction circuit 3 moves the defective pixel data (second pixel data) specified from the defective pixel position information in the defective pixel memory 44 to the left and right of the defective pixel data (that is, Correction is performed on the basis of two pieces of pixel data at positions separated from each other by two adjacent pixel data in the pixel raster data 200. In other words, the defective pixel correction circuit 3 uses the two pieces of pixel data that are closest to the defective pixel data and that passes through the second output path 73 in the same manner as the defective pixel data. Then, the defective pixel data is corrected. Specifically, for example, the defective pixel correction circuit 3 obtains an average value of two values A and B respectively represented by the two pixel data, and substitutes the average value as the original value of the defective pixel data ( The correction method is not limited to this, and other methods may be adopted.

  Further, for example, when the second resolution (for example, 1600 dpi) smaller than the first resolution is designated and the document reading image data of that resolution is generated, the control unit 45 generates the first resolution on the staggered array CCD 27. Signal charges are output only from the pixel sensors in the column (or the second column). As a result, one pixel raster data stored in the pixel data memory 42 includes raster data 200 including only the first pixel data 100A obtained via the first output path 71, as shown in FIG. Become.

  When there is defective pixel data in the pixel raster data 200, the defective pixel correction circuit 3 sets the pixel data adjacent to the left and right of the defective pixel data as in the first resolution, as shown in FIG. Correction is performed based on two pixel data at separate positions (specifically, an average value of two values a and b represented by the two pixel data is obtained, and the average value is calculated based on the original value of the defective pixel data. As an alternative value).

  The above is the description of the first embodiment.

  In the first embodiment, when the pixel data constituting the pixel raster data 200 are all pixel data passing through the same output path, the defective pixel correction circuit 3 is adjacent to the defective pixel data on the left and right. The defective pixel data may be corrected using the pixel data to be corrected.

  In the first embodiment, the CCD has a staggered arrangement in which a large number of pixel sensors are arranged in two rows for each color. When there are two or more readout paths of the pixel sensor (for example, in the case of so-called double-side readout), the defective pixel correction technique according to the present embodiment can be applied.

  According to the first embodiment, correction of defective pixel data in pixel raster data is performed based on pixel data that has passed through the same output path as the defective pixel correction data (in other words, for example, each color If there are M output paths for each of a large number of pixel sensors, and pixel raster data has a configuration in which pixel data passing through each output path are arranged alternately, defective pixel data Is corrected using two pieces of pixel data separated by M−1 on the left and right sides of For this reason, even if the characteristics of the transfer channel on the output path of the charge output from each pixel sensor or the characteristics of the charge-voltage conversion device, etc., the pixel data characteristics relating to the obtained pixel data (for example, the same amount of light is applied to the CCD). Even if the linearity representing the relationship between the position of each pixel sensor and its pixel data in the case of irradiation is different), the defective pixel correction data is the pixel data via the same output path, that is, the same Since correction is performed based on pixel data that can have pixel data characteristics, the data is appropriately corrected.

  Next, a second embodiment will be described. At this time, the description overlapping with the first embodiment is omitted or simplified, and the difference from the first embodiment will be mainly described.

  In the second embodiment, when the first resolution (for example, 3200 dpi) is specified and the document reading image data of the resolution is generated, the control unit 45 receives signals from all the pixel sensors on the staggered CCD 27. Electric charge is output. As a result, one pixel raster data stored in the pixel data memory 42 belongs to the first pixel data 300A obtained from a plurality of pixel sensors belonging to the first column and the second column, as shown in FIG. The second pixel data 300B obtained from a plurality of pixel sensors is raster data 300 that is alternately arranged.

  In this case, for example, when the defective pixel data is a certain second pixel data output from a certain pixel sensor belonging to the second column, the defective pixel correction circuit 3 performs the following process. Correction processing of defective pixel data is performed.

  That is, as shown in FIG. 7, the defective pixel correction circuit 3 makes the defective pixel data (second pixel data) specified from the defective pixel position information in the defective pixel memory 44 adjacent to the left and right of the defective pixel data. Correction is performed on the basis of two pieces of pixel data at a position separated by one pixel data. In other words, the defective pixel correction circuit 3 is the two pixel data closest to the defective pixel data, and is in the same column as the pixel sensor that output the defective pixel data, and the right and left of the pixel sensor. The defective pixel data is corrected using the two pixel data output from the adjacent pixel sensors. Specifically, for example, the defective pixel correction circuit 3 obtains an average value of two values C and D represented by the two pixel data, and substitutes the average value as the original value of the defective pixel data.

  In addition, when a second resolution (for example, 1600 dpi) smaller than the first resolution is designated and the document reading image data having the resolution is generated, the control unit 45 generates the first column (on the staggered array CCD 27). Alternatively, signal charges are output only from the pixel sensors in the second column). Therefore, as a result, one pixel raster data stored in the pixel data memory 42 is data including only a plurality of first pixel data respectively output from a plurality of pixel sensors belonging to the first column. In this case, when there is defective pixel data in the pixel raster data, the defective pixel correction circuit 3 positions the pixel data adjacent to the left and right of the defective pixel data one by one, as in the first resolution. Is corrected based on the two pieces of pixel data.

  The above is the description of the second embodiment.

  In the second embodiment, when the plurality of pixel data constituting the pixel raster data are pixel data respectively output from the plurality of pixel sensors belonging to the same column, the defective pixel correction circuit 3 The defective pixel data may be corrected using pixel data adjacent to the defective pixel data on the left and right.

  In the second embodiment, the CCD has a large number of pixel sensors arranged in two columns for each color. However, the defective pixel according to the present embodiment may also be arranged over three or more columns. Correction techniques can be applied. That is, for example, when pixel sensors are arranged in three columns for each color, when defective pixel data is output from one pixel sensor belonging to the third column, the defective pixel correction circuit 3 is the two pixel data closest to the defective pixel data, and the two pixels output from the pixel sensors on the left and right sides of the pixel sensor in the same column as the pixel sensor that output the defective pixel data The defective pixel data can be corrected using the data.

  According to the second embodiment, correction of defective pixel data in pixel raster data is performed based on pixel data output from pixel sensors belonging to the same column as the pixel sensor that output the defective pixel correction data. (In other words, for example, when a large number of pixel sensors for each color are arranged in N columns, and the pixel raster data has a configuration in which pixel data for each column is alternately arranged, The defective pixel data is corrected by using two pixel data separated by N−1 on the left and right sides). For this reason, pixel sensor characteristics relating to the output of the pixel sensor for each column (for example, linearity representing the relationship between the amount of received light and the output pixel data, for example, depending on the physical distance between the first column and the second column of the pixel sensor) ) May be different, the defective pixel correction data may be pixel data output from pixel sensors belonging to the same column as the pixel sensor that outputs the defective pixel correction data, that is, pixel data that may have the same pixel sensor characteristics. Therefore, the data is appropriately corrected.

  The preferred embodiments of the present invention have been described above, but these are examples for explaining the present invention, and the scope of the present invention is not limited to these embodiments. The present invention can be implemented in various other forms. For example, when the signal charges are output only from the pixel sensors belonging to one of the first column and the second column, the control unit 45 determines which column pixel sensor is used, for example, for each column. The presence or absence of defective pixel data and the number of defective pixel data may be detected in the pixel raster data, and the column with the smaller number of defective pixel data may be selected and used. Further, as shown in FIG. 2, the first output path 71 and the second output path 73 are provided between the first column and the second column of the pixel sensors (in other words, inside each column). Alternatively, it may be provided outside each row.

1 is a block diagram showing a configuration of an image scanner according to a first embodiment of the present invention. FIG. 3 is a schematic diagram of a configuration of a staggered CCD 27; The figure which shows the structure of the signal conversion part 29. FIG. The figure which shows pixel raster data when 1st resolution is designated. The figure for demonstrating the correction method of the defective pixel data in pixel raster data when 1st resolution is designated. The figure for demonstrating the correction method of the defective pixel data in pixel raster data when 2nd resolution is designated. The figure for demonstrating the correction method of the defective pixel data in pixel raster data in case the 1st resolution is designated in the 2nd Example.

Explanation of symbols

3 Defective pixel correction circuit 27 Staggered CCD
29 Signal converter 44 Defective pixel memory 45 Controller

Claims (8)

An apparatus for correcting defective pixel data that may be included in pixel raster data having a large number of pixel data output from an image sensor that has received light,
The image sensor includes a plurality of pixel sensors that output pixel data corresponding to the amount of received light in a row, and the first pixel sensor group among the plurality of pixel sensors passes through a first output path. Pixel data is output, and pixel data is output from the second pixel sensor group via the second output path,
The pixel data adjacent to each target pixel data in the pixel raster data in the column direction is pixel data output via an output path different from an output path through which the target pixel data passes,
When defective pixel data is included in predetermined pixel raster data, based on pixel data output from the same pixel sensor group as the pixel sensor group that has output the defective pixel data out of the pixel data constituting the raster data A defective pixel correction apparatus, wherein the defective pixel data is corrected. 2. The defective pixel data is corrected based on a plurality of pixel data closest to the defective pixel data among pixel data output from the same pixel sensor group as the pixel sensor group that output the defective pixel data. The defective pixel correction apparatus described. An apparatus for correcting defective pixel data that may be included in pixel raster data having a large number of pixel data output from an image sensor that has received light,
The image sensor includes a plurality of pixel sensors that output pixel data corresponding to the amount of received light in a column, and a first pixel sensor group among the plurality of pixel sensors constitutes a first pixel sensor column. The second pixel sensor group constitutes the second pixel sensor row,
The pixel data adjacent to each target pixel data in the pixel raster data in the column direction is pixel data output from a pixel sensor group constituting a column different from the pixel sensor group outputting the target pixel data,
When defective pixel data is included in predetermined pixel raster data, based on pixel data output from the same pixel sensor group as the pixel sensor group that has output the defective pixel data out of the pixel data constituting the raster data A defective pixel correction apparatus, wherein the defective pixel data is corrected. 4. The defective pixel data is corrected based on a plurality of pixel data closest to the defective pixel data among pixel data output from the same pixel sensor group as the pixel sensor group that output the defective pixel data. The defective pixel correction apparatus described.
The defective pixel correction apparatus according to claim 1. The plurality of pixel sensors are arranged in a staggered pattern on the image sensor.
The defective pixel correction apparatus according to claim 1 or 3. An image sensor having a number of pixel sensors that receive light and output a number of pixel data corresponding to the amount of light received;
An image input device comprising the defective pixel correction device according to claim 1. A computer program for correcting defective pixel data that may be included in pixel raster data having a large number of pixel data output from an image sensor that has received light,
The image sensor includes a plurality of pixel sensors that output pixel data corresponding to the amount of received light in a row, and the first pixel sensor group among the plurality of pixel sensors passes through a first output path. Pixel data is output, and pixel data is output from the second pixel sensor group via the second output path,
The pixel data adjacent to each target pixel data in the pixel raster data in the column direction is pixel data output via an output path different from an output path through which the target pixel data passes,
When defective pixel data is included in predetermined pixel raster data, based on pixel data output from the same pixel sensor group as the pixel sensor group that has output the defective pixel data out of the pixel data constituting the raster data A computer-readable computer program for causing a computer to execute the step of correcting the defective pixel data. A computer program for correcting defective pixel data that may be included in pixel raster data having a large number of pixel data output from an image sensor that has received light,
The image sensor includes a plurality of pixel sensors that output pixel data corresponding to the amount of received light in a column, and a first pixel sensor group among the plurality of pixel sensors constitutes a first pixel sensor column. The second pixel sensor group constitutes the second pixel sensor row,
The pixel data adjacent to each target pixel data in the pixel raster data in the column direction is pixel data output from a pixel sensor group constituting a column different from the pixel sensor group outputting the target pixel data,
When defective pixel data is included in predetermined pixel raster data, based on pixel data output from the same pixel sensor group as the pixel sensor group that has output the defective pixel data out of the pixel data constituting the raster data A computer-readable computer program for causing a computer to execute the step of correcting the defective pixel data.

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