JP2009177344A - Imaging element driving unit, and imaging element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To image a desired object with a high resolution while maintaining a high frame rate. <P>SOLUTION: The imaging element has an image feature determination part, a register, and a timing control part. The image feature determination part detects a main object in the entire image on the basis of image signals generated by prior imaging. The register sets the region of receiving light of the main object on a light receiving surface as a first region, and the register sets the other area as a second region. The timing control part makes the simultaneous read of 2 pixels be executed in 9-17 columns set in the first region. The timing control part makes the simultaneous read of 4 pixels be executed in 1-8 and 17-24 columns set in the second region. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image sensor driving apparatus that causes an image sensor to capture a high-resolution moving image while ensuring a frame rate.

  A digital camera that has an image sensor with a large number of pixels and can capture still images and moving images is known. When shooting a moving image with such a digital camera, it is known to thin out pixels for outputting signals from the image sensor. Note that pixel thinning refers to reading out signals from some pixels during the reading period of the entire image when outputting image signals from the image sensor.

  Decreasing the frame rate is prevented by thinning out the output pixels. That is, the reading operation on the entire light receiving surface is speeded up while keeping the time required for generating and outputting the pixel signal by a single pixel constant. However, by performing pixel thinning necessary to prevent a decrease in the frame rate, there is a problem that a false pattern or moire occurs because actual information is lost.

  In view of this, it has been proposed to obtain an image signal having the same data size as that obtained when thinning output is performed by outputting signals from all pixels of the image sensor and performing pixel addition in subsequent image processing (see Patent Document 1). ). Although it is possible to prevent the occurrence of moire by adding pixels, it is difficult to increase the output speed of the image sensor because it is necessary to output signals from all pixels of the image sensor.

In addition, it has been proposed to perform thinning output while performing pixel addition in the image sensor (see Patent Document 2). While preventing the frame rate from being lowered by thinning out output, it is possible to reduce false patterns and moire by pixel addition. However, since the number of pixels to be added is determined uniformly according to the number of pixels for moving images on the entire light receiving surface, a high resolution is maintained by effectively utilizing pixel signals obtained according to the characteristics of the image. There was no problem.
JP 2003-333610 A Japanese Patent Laid-Open No. 9-247689

  Accordingly, an object of the present invention is to provide an image sensor driving apparatus that captures a moving image with little image degradation according to an image to be captured while ensuring a frame rate.

  In the image pickup device driving apparatus according to the present invention, pixels are arranged along the first and second directions on the light receiving surface, and each pixel generates a pixel signal according to the amount of received light individually or in the first direction and / or Alternatively, an image sensor driving apparatus for driving an XY address type image sensor capable of simultaneously outputting pixel signals generated by a plurality of pixels along the second direction, wherein each of the plurality of partial regions obtained by dividing the light receiving surface A setting unit configured to set a first region or a second region to be imaged at a lower resolution than the first region, and a partial region set to the first region individually from pixels arranged along the first direction. In the partial region set as the second region by outputting the pixel signal or simultaneously outputting m1 (m1 is a positive integer) pixel signal to the image sensor, n1 pixels are arranged in the first direction. Pixel signal of (n1> m1) It is characterized by a control unit to be executed by the image pickup element simultaneously output.

  Furthermore, it is preferable that the number determined as n1 increases as the number determined as m1 decreases.

  In addition, the setting unit sets the plurality of partial areas as the first area, the second area, or the third area that captures an image with a lower resolution than the second area, and the control section sets the third area as the third area. It is preferable to cause the image sensor to simultaneously output s1 (s1> n1) pixel signals from the pixels arranged in the first direction.

  In addition, the control unit causes the imaging device to execute output of individual pixel signals or simultaneous output of m2 pixel signals from the pixels arranged in the second direction in the partial region set as the first region, In the partial region set as the second region, it is preferable to cause the imaging device to simultaneously output n2 (n2> m2) pixel signals from the pixels arranged in the second direction.

  The setting unit estimates a main subject in the entire image previously captured by the image sensor, sets a partial region where the main subject is captured as a first region, and a portion other than the partial region where the main subject is captured It is preferable to set the area as the second area.

  Alternatively, the setting unit estimates a moving body that is moving in the whole of a plurality of images previously captured by the image sensor, sets a partial region in which the moving body is captured as a first region, and the mobile body captures an image. It is preferable to set the partial area other than the partial area as the second area.

  Alternatively, the setting unit estimates a moving body that is moving in the whole of the plurality of images previously captured by the image sensor, calculates a moving direction of the moving body, and determines a partial region and the moving body that captured the moving body. The partial area at the position in the moving direction from the captured partial area is set as the first area, and the partial area other than the partial area at the position in the moving direction from the partial area where the moving body is imaged It is preferable to set the partial region as the second region.

  Each pixel is covered with any one of a plurality of types of color filters, and the control unit preferably causes the pixels covered with the same color filter to simultaneously output pixel signals.

  In the image pickup device of the present invention, pixels are arranged along the first and second directions on the light receiving surface, and each pixel generates pixel signals generated according to the amount of received light individually or in the first direction and / or the second direction. An XY addressing imaging device main body that can simultaneously output pixel signals generated by a plurality of pixels along the direction of the first and second partial regions obtained by dividing the light receiving surface are lower than the first region or the first region. In the setting unit for setting the second area to be imaged at the resolution and the partial area set to the first area, the output of individual pixel signals from the pixels arranged in the first direction or m1 (m1 is positive) In the partial area set as the second area by causing the image sensor to execute simultaneous output of pixel signals of n), simultaneous output of n1 (n1> m1) pixel signals from the pixels arranged in the first direction. That causes the image sensor to execute It is characterized in that it comprises and.

  According to the present invention, it is possible to capture an optical image with a high resolution at a part of the light receiving surface and to keep the frame rate high in order to increase the number of pixels for simultaneous readout in other areas.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram schematically showing an internal configuration of a digital camera having an image sensor driving device to which an embodiment of the present invention is applied. The digital camera 10 includes a lens 11, an image sensor 20, a digital signal processing circuit (DSP) 12, a system controller 13, a timing generator 14, and the like.

  The lens 11 is optically connected to the image sensor 20. An optical image of the subject that passes through the lens 11 enters the light receiving surface of the image sensor 20. The image sensor 20 is, for example, a CMOS image sensor. When the optical image of the subject is received on the light receiving surface, an image signal corresponding to the optical image is generated.

  The image signal generated by the image sensor 20 is converted from an analog signal to a digital signal by the A / D converter 15. The image signal converted into the digital signal is sent to the DSP 12.

  The image signal sent to the DSP 12 is stored in the DRAM 16 which is a working memory for signal processing. The image signal stored in the DRAM 16 is subjected to predetermined signal processing in the DSP 12.

  The image signal that has undergone predetermined signal processing is sent to the monitor 17. On the monitor 17, an image corresponding to the transmitted image signal is displayed. The image signal that has undergone predetermined signal processing can be stored in an external memory 18 connected via a connector (not shown).

  Each part of the digital camera 10 is controlled by the system controller 13. The imaging device 20 and the shutter 19 are driven by the timing generator 14. The image sensor 20 and the shutter 19 are driven to generate an image signal.

  Next, the configuration of the image sensor 20 will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the image sensor.

  The image sensor 20 is a CMOS image sensor, and includes an image sensor body 21, a timing control unit 22, a register (control unit) 23, an image feature determination unit (setting unit) 24, and the like.

  The optical image of the subject is received by the image sensor body 21 and an image signal is generated. Based on the image signal, the image feature determination unit 24 determines a subject estimated as a main imaging target in the entire captured image. The register 23 determines a reading method of the pixel signal constituting the image signal based on the determined subject. The timing control unit 22 drives the image sensor body 21 based on the readout method determined by the register 23 and the clock signal and field signal transmitted from the timing generator 14.

  The image sensor body 21 includes a light receiving unit 25, a row selection circuit 26, a column selection circuit 27, a horizontal readout line 28, a column selection transistor 29, and the like. The light receiving unit 25 and the row selection circuit 26 are directly connected. The horizontal readout line 28 is connected to the light receiving unit 25 via the column selection transistor 29. The column selection circuit 27 and the column selection transistor 29 are connected.

  A plurality of pixels P are arranged on the imaging surface of the light receiving unit 25 in a matrix, that is, along the column direction (first direction) and the row direction (second direction). Each pixel P is covered with one of an R (ed) color filter, a G (reen) color filter, and a B (lue) color filter. The color filter is arranged according to the Bayer method.

  Therefore, two types of color filters, an R color filter and a G color filter, are alternately and repeatedly arranged in the row direction. Alternatively, two types of color filters, the G color filter and the B color filter, are alternately and repeatedly arranged.

  Also, two types of color filters, an R color filter and a G color filter, are alternately and repeatedly arranged in the column direction. Alternatively, the G color filter and the B color filter are alternately and repeatedly arranged.

  The pixel P covered with the R color filter generates a pixel signal corresponding to the amount of received light of the red component. The pixel P covered with the G color filter generates a pixel signal corresponding to the amount of received light of the green component. The pixel P covered with the B color filter generates a pixel signal corresponding to the amount of received light of the blue component. The image signal of the entire subject image is composed of a plurality of pixel signals.

  The generated pixel signal is output individually from each pixel P or simultaneously from a plurality of pixels P. When signals are output simultaneously from a plurality of pixels P, the signal components of the pixels P to be output simultaneously are averaged and output. The pixel P that outputs the pixel signal is selected directly or indirectly by the row selection circuit 26 and the column selection circuit 27.

  A row of pixels P to be read is selected by the row selection circuit 26. A pixel signal output from the selected pixel P is output to the column selection transistor 29. The pixel signal output to the column selection transistor 29 is selected by the column selection circuit 27 and output to the horizontal readout line 28.

  The pixel signal output to the horizontal readout line 28 is sent to the DSP 23 via the output unit 30 and the A / D converter 15. The pixel signal is subjected to predetermined signal processing in the DSP 12 and sent as an image signal to the monitor 17 or the external memory 18.

  The row selection circuit 26 and the column selection circuit 27 are connected to the timing control unit 22. The timing control unit 22 drives the row selection circuit 26 and the column selection circuit 27 to select a pixel P that outputs a pixel signal.

  The pixel signal is read out from the image sensor body 21 by a combination of individual readout of pixel signals in the column direction and row direction, first and second fixed simultaneous readouts, and first and second variable simultaneous readouts. Is done.

  The individual readout methods in the column direction from the pixels P arranged in 4 rows and 24 columns, the first and second fixed simultaneous readouts, and the first and second variable simultaneous readouts will be described below as examples. To do. In the following description, the row numbers of the pixels P are counted from top to bottom. The column number of the pixel P is counted from the left to the right.

  In the individual readout method, the first row selection signal ΦSL1 transmitted from the row selection circuit 26 to the pixel P in the first row is switched to HIGH (see the ΦSL1 column in FIG. 3), and the pixel P in the first row is selected. By selecting the pixels P in the first row, pixel signals can be output from all the pixels P arranged in the first row.

  In a state where the pixels P in the first row are selected, the column selection signals ΦSR1 to ΦSR24 that are separately transmitted from the column selection circuit 27 to all the column selection transistors 29 are sequentially switched to HIGH, and from the first column to the last. The column selection transistors 29 up to the 24th column, which are columns, are sequentially selected by the column selection circuit 27 (see P1 in FIG. 3).

  The selection of the column selection transistor 29 is executed by the conduction / non-conduction of the column selection transistor 29. When the column selection transistor 29 is turned on, the pixel signals of the pixels P from the first column to the 24th column in the first row are sequentially output from the image sensor 20.

  When the output of the pixel signal from the pixel P in the first row is completed, the selection of the pixel P in the first row is canceled and the pixel P in the second row is selected by the row selection circuit 26 (see FIG. 3ΦSL2). As in the first row, the column selection transistor 29 is selected by the column selection circuit 27, and the pixel signals of the pixels P from the first column to the 24th column in the second row are sequentially output from the imaging device 20 (FIG. 3). (See symbol P2).

  Thereafter, pixel signals are output individually for the pixels P in the third and fourth rows in the same manner as in the first and second rows. As described above, in the individual readout method, pixel signals are individually read out from all the pixels P (see FIG. 4).

  In the first fixed simultaneous readout method, the first row selection signal ΦSL1 is switched to HIGH from the row selection circuit 26 (see the column ΦSL1 in FIG. 5), and the pixels P in the first row are selected. In a state where the pixels P in the first row are selected, three column selection signals every two columns, that is, column selection signals of three columns covered by the same color filter are simultaneously switched to HIGH. The three column selection signals are switched to HIGH in order, and the column selection transistor 29 of each column is selected.

  For example, the first, third, and fifth column selection transistors 29 are first selected (see timing T1 in FIG. 5), and then the second, fourth, and sixth column selection transistors 29,..., 20, 22, and 24 columns. The third column selection transistor 29 is selected in order (see P1 in FIG. 5).

  By selecting and conducting the three column selection transistors 29 simultaneously, the three pixel signals of the selected column are averaged and output. For example, the pixel signals in the first, third, and fifth columns are averaged and output as a pixel signal in the 1 ′ column of the read pixel arrangement in which the pixel arrangement of the image sensor 20 is compressed to 1/3 in the column direction (see FIG. 6 read pixel arrangement column 1 'column).

  Similarly, the pixel signals in the second, fourth, and sixth columns are averaged and output as the pixel signal in the 2 'column of the readout pixel arrangement. Similarly, in the subsequent columns, three pixel signals every two columns are averaged and output.

  When the output of the pixel signal from the pixel P in the first row is completed, the selection of the pixel P in the first row is cancelled. Thereafter, similarly for the pixels P in the second row to the fourth row, three pixel signals every two columns in each row are averaged and read out as in the first row (see FIG. 6).

  In the second fixed simultaneous readout method, the first row selection signal ΦSL1 is switched to HIGH from the row selection circuit 26 (see the column ΦSL1 in FIG. 7), and the pixel P in the first row is selected. In a state where the pixels P in the first row are selected, the column selection signals at both ends among the three column selection signals arranged continuously every two columns are simultaneously switched to HIGH. The column selection signals at both ends are switched to HIGH in order, and the entire 2/3 column selection transistors 29 are selected.

  For example, the column selection transistors 29 in the first and fifth columns are first selected (see timing T1 in FIG. 7), and then the column selection transistors 29 in the second and sixth columns,. They are selected in order (see P1 in FIG. 7).

  By selecting and conducting two column selection transistors 29 simultaneously, the two pixel signals in the selected column are averaged and output. For example, the pixel signals in the first and fifth columns are averaged and output as the pixel signal in the 1 ′ column of the read pixel arrangement in which the pixel arrangement of the image sensor 20 is compressed to 1/3 in the column direction (see FIG. 8). Pixel arrangement column 1 ′ column). Similarly, the pixel signals in the second and sixth columns are averaged and output as pixel signals in the 2 'column of the readout pixel arrangement. Similarly, two pixel signals are averaged and output.

  When the output of the pixel signal from the pixel P in the first row is completed, the selection of the pixel P in the first row is cancelled. Thereafter, similarly for the pixels P in the second to fourth rows, the two pixel signals are averaged and output as in the first row (see FIG. 8).

  Next, the first and second variable simultaneous readout systems will be described. As will be described later, when performing the first and second variable simultaneous reading, an area defined by an arbitrary row and / or column is classified as the first area, and the other areas are classified as the second area. The Note that the first region is a region that receives light with a high resolution, and the second region is a region that receives light with a lower resolution than the first region.

  In the following description of the first variable simultaneous readout method, it is assumed that the region formed by the pixels P in the 9th to 16th columns is classified as the first region. In the following description of the second variable simultaneous readout method, it is assumed that the region formed by the pixels P in the 11th to 14th columns is classified as the first region.

  In the first variable simultaneous readout method, the row selection circuit 26 switches the first row selection signal ΦSL1 to HIGH (see the column ΦSL1 in FIG. 9), and the pixel P in the first row is selected. In the state where the pixel P in the first row is selected, for every column belonging to the second region, that is, the first to eighth columns and the 17th to 24th columns, every four column selection signals are switched to HIGH simultaneously. For the columns belonging to the first region, that is, the 9th to 16th columns, two column selection signals every other column are simultaneously switched to HIGH, and the respective column selection transistors 29 are selected.

  For example, in the first to eighth columns as the second region, the column selection transistors 29 in the first, third, fifth, and seventh columns are first selected (see T1 in FIG. 9), and then 2, 4, 6, The column selection transistor 29 in the eighth column is selected.

  In the 9th to 16th columns, which are the first region after the 8th column, the 9th and 11th column selection transistors 29, 10 and the 12th column selection transistors 29, 13 and 15th column. The column selection transistors 29 and the groups of the column selection transistors 29 in the 14th and 16th columns are simultaneously selected in order (see P1 in FIG. 9).

  By simultaneously selecting 2 or 4 column selection transistors 29, 2 or 4 pixel signals of the selected column are averaged and output.

  For example, the pixel signals in the first, third, fifth, and seventh columns are averaged and output as the pixel signal in the 1 'column of the readout pixel arrangement (see readout pixel arrangement column 1' in FIG. 10). Similarly, the pixel signals in the second, fourth, sixth, and eighth columns are averaged and output as the pixel signal in the 2 'column of the readout pixel arrangement (see the readout pixel arrangement column 2' column in FIG. 10). Similarly, in the 17th to 24th columns, the four pixel signals are averaged and output.

  In addition, the pixel signals in the ninth and eleventh columns are averaged and output as pixel signals in the 3 'column of the readout pixel arrangement (see readout pixel arrangement column 3' in FIG. 10). Similarly, the pixel signals in the 10th and 12th columns are averaged and output as pixel signals in the 4 'column of the readout pixel arrangement (see readout pixel arrangement column 4' in FIG. 10). Similarly, in the 13th to 16th columns, the two pixel signals are averaged and output.

  When the output of the pixel signal from the pixel P in the first row is completed, the selection of the pixel P in the first row is cancelled. Thereafter, similarly for the pixels P in the second row to the fourth row, similarly to the first row, four pixels in every second column in the columns belonging to the second region (1-8 columns, 17-24 columns). The signals are averaged, and two pixel signals every two columns in the columns (9 to 16 columns) belonging to the first region are averaged and output (see FIG. 10).

  In the second variable simultaneous readout method, the row selection circuit 26 switches the first row selection signal ΦSL1 to HIGH (see the column ΦSL1 in FIG. 11), and the pixel P in the first row is selected. In a state where the pixels P in the first row are selected, five column selection signals every other column are simultaneously switched to HIGH for the columns belonging to the second region, that is, the columns 1 to 10 and 15 to 24, For the columns belonging to the first region, that is, the 11th to 14th columns, the column selection signal is individually switched to HIGH, and each column selection transistor 29 is selected.

  For example, in the 1st to 10th columns that are the second region, the column selection transistors 29 in the 1, 3, 5, 7, and 9th columns are first selected (see T1 in FIG. 11), and then 2, 4, The sixth, eighth and tenth column selection transistors 29 are selected.

  In the 11th to 14th columns, which are the first area after the 10th column, the column selection transistors 29 in the 10th to 14th columns are individually selected in order (see P1 in FIG. 11).

  By the selection of the column selection transistor 29, the pixel signals in the first, third, fifth, seventh, and ninth columns are averaged in the 1 ′ column of the readout pixel arrangement, as in the first variable simultaneous readout method. It is output as a pixel signal (see the readout pixel arrangement column 1 ′ column in FIG. 12). Similarly, the pixel signals in the second, fourth, sixth, eighth, and tenth columns are averaged and output as the pixel signal in the 2 'column of the readout pixel arrangement (see the readout pixel arrangement column 2' column in FIG. 12). Similarly, in the 15th to 24th columns, five pixel signals are averaged and output.

  In addition, the pixel signals in the 11th to 14th columns are output individually and sequentially as pixel signals in the 3 'to 6' columns of the readout pixel arrangement (see the readout pixel arrangement columns 3 'to 6' in FIG. 12).

  When the output of the pixel signal from the pixel P in the first row is completed, the selection of the pixel P in the first row is cancelled. Thereafter, similarly for the pixels P in the second row to the fourth row, five pixels in every second column in the columns belonging to the second region (1 to 10 columns, 15 to 24 columns) as in the first row. The signals are averaged, and each pixel signal is individually and conveniently output in columns (11 to 14 columns) belonging to the first region (see FIG. 12).

  The digital camera 10 can capture still images and moving images. Still image shooting and moving image shooting are switched by input to a switch (not shown) provided in the digital camera 10.

  When capturing a still image, the image sensor body 21 is driven so that pixel signals are output in the row direction and the column direction by the individual readout method.

  When capturing a moving image, a pixel signal is output by any one of a combination of the first and second fixed simultaneous readout methods set by the user and the first and second variable simultaneous readout methods. As described above, the image sensor body 21 is driven.

  Note that the first and second fixed simultaneous readout methods are suitable for imaging an object with the same resolution as a whole. Further, the first variable simultaneous readout method is suitable for imaging a main subject with high resolution in the whole. Further, the second variable simultaneous readout method is suitable for imaging a main subject with higher resolution.

  When the first and second variable simultaneous readout methods are executed, the image feature determination unit 24 and the register 23 classify whether the pixel P on the light receiving surface belongs to the first region or the second region. The Note that the image feature determination unit 24 pauses during still image capturing and when the first and second fixed simultaneous readout methods are executed.

  As described above, the image feature determination unit 24 receives a plurality of image signals output from the output unit 30 in time series. The image feature determination unit 24 detects a moving object in the entire image based on the plurality of image signals. Note that the moving subject is detected based on differences and motion vectors obtained from a plurality of image signals. Further, the image feature determination unit 24 calculates the moving direction of the moving subject.

  Based on the detected subject and the moving direction, the register 23 sets a region that receives the moving subject and a region that moves the region that receives the subject along the moving direction as the first region and the other regions. Classify as the second region. The register 23 designates the first region and the second region in the row direction and / or the column direction based on the classification result, drives the timing control unit 22, and executes the variable simultaneous reading method. Let

  For example, when the detected position of the subject is near the center of the light receiving surface and the amount of movement is very small, or when it vibrates with a small amplitude, as shown in FIG. The vicinity of the center in the row direction is classified as a first region in the row direction. Furthermore, the vicinity of the center in the column direction is also classified as the first region in the column direction.

  Therefore, the vicinity of the center (see the shaded area in the mesh) classified in the first region in both the row direction and the column direction is imaged so as to have a high resolution. In addition, a region extending in the vertical direction and the horizontal direction from the vicinity of the center where only one of the row direction and the column direction is classified as the first region (see the single hatched portion) has a medium resolution, and the other regions The image is taken so that the resolution is low.

  Further, when the detected position of the subject is near the center of the light receiving surface and is moving to the left and right, as shown in FIG. 14, the vicinity of the center in the column direction on the light receiving surface is the first region in the column direction. are categorized. Accordingly, the vicinity of the center (see the single oblique line) classified as the first area in the column direction is imaged so that the resolution is medium and the resolution is low in other areas.

  Further, when the detected position of the subject is near the center of the light receiving surface and moves up and down, as shown in FIG. 15, the center of the light receiving surface near the center in the row direction is the first region in the row direction. are categorized. Therefore, the vicinity of the center (see the single hatched portion) classified as the first region in the row direction is imaged so that the resolution is medium and the resolution is low in other regions.

  According to the imaging device driving apparatus having the above-described configuration, it is possible to increase the resolution only in a necessary region and average and output a plurality of pixel signals in other regions. Therefore, it is possible to capture a clear moving image of the main subject while maintaining a high frame rate.

  In the present embodiment, in the first variable simultaneous readout method, two pixel signals are simultaneously read out from the first area, and four pixel signals are simultaneously read out from the second area. In the variable simultaneous readout method, each pixel signal is individually read from the first area and five pixel signals are simultaneously read from the second area. Any number may be determined as long as the number n1 of pixel signals to be simultaneously read out for the second region is larger than the number m1 of pixel signals to be output.

  In the present embodiment, the area defined by any row and / or column in the first and second variable simultaneous readout systems is classified as either the first or second area. Further, it may be classified into a third region that receives light at a lower resolution than the second region. Furthermore, it may be classified into fourth,..., Zth regions that receive light at a lower resolution than the third region. In the case of classifying into the third area, the second signal area can be obtained by increasing the number of pixel signals s1 to be read simultaneously to the third area from the number n1 of pixel signals to be simultaneously read to the second area. It is possible to capture an image received in the third region with a resolution lower than that of the first region.

  In this embodiment, the moving object is detected in the entire image based on differences and motion vectors obtained from a plurality of image signals. However, the image is picked up with high resolution by another method. The main subject to be detected may be detected.

  For example, a main subject may be detected based on frequency component analysis or density histogram analysis in a single image signal. The detected moving direction of the subject can be detected by performing a conventionally known tracking process on subsequent image signals.

  In the present embodiment, the moving direction of the subject is detected, and even the region shifted from the position of the subject in the moving direction is classified as the first region, but the moving direction may not be detected. The image sensor 20 may be driven so that the position of the subject is simply detected and only the periphery of the subject is set to the first region, that is, the first region in the row direction and the column direction.

  In the present embodiment, the timing control unit 22, the register 23, and the image feature determination unit 24 are provided in the image sensor 20, but may be provided outside the image sensor 20.

  In this embodiment, the color filter is arranged according to the Bayer method, but may be arranged according to another method. In this embodiment, the primary color filter is used, but filters of other colors may be used. For example, a complementary color filter may be used. However, when an arrangement according to another method or a filter of another color is used, it is necessary to simultaneously read out pixels covered by the same color filter. Note that the present embodiment can also be applied to a monochrome image sensor that is not covered with a color filter.

  In this embodiment, the image pickup device is a CMOS image pickup device. However, the same effect as in this embodiment can be obtained by using any image pickup device of the XY address type.

1 is a block diagram schematically showing an internal configuration of a digital camera having an image sensor driving device to which an embodiment of the present invention is applied. It is a block diagram which shows the structure of an image pick-up element. It is a timing chart which shows the drive method of the image sensor by an individual readout method. FIG. 6 is a correspondence diagram between pixel signals generated by each pixel and pixel signals output from the image sensor in the individual readout method. It is a timing chart which shows the drive method of the image sensor by the 1st fixed simultaneous reading system. It is a correspondence diagram of the pixel signal which each pixel generates, and the pixel signal output from the image sensor at the time of the 1st fixed simultaneous reading system. It is a timing chart which shows the drive method of the image sensor by the 2nd fixed simultaneous reading system. FIG. 6 is a correspondence diagram between a pixel signal generated by each pixel and a pixel signal output from an image sensor in the second fixed simultaneous readout method. It is a timing chart which shows the drive method of the image sensor by the 1st variable simultaneous reading system. It is a correspondence diagram of the pixel signal which each pixel generates, and the pixel signal output from the image sensor at the time of the 1st variable simultaneous reading system. 6 is a timing chart showing a method of driving an image sensor by a second variable simultaneous readout method. FIG. 6 is a correspondence diagram between a pixel signal generated by each pixel and a pixel signal output from an image sensor in the second variable simultaneous readout method. It is a state diagram which shows the state in which the 1st area | region is designated in both the row direction and the column direction. It is a state diagram which shows the state in which the 1st area | region is designated in the column direction. It is a state diagram which shows the state in which the 1st area | region is designated in the row direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Digital camera 14 Timing generator 20 Image pick-up element 21 Image pick-up element main body 22 Timing control part 23 Register 24 Image feature determination part 26 Row selection circuit 27 Column selection circuit ΦSL1, ΦSL2, 1st row selection signal ΦSR1-ΦSR24 Column selection signal

Claims (9)

Pixels are arranged along the first and second directions on the light receiving surface, and pixel signals generated by the respective pixels according to the amount of received light are individually or along the first direction and / or the second direction. An image sensor driving apparatus for driving an XY address type image sensor capable of simultaneously outputting the pixel signals generated by a plurality of the pixels,
A setting unit that sets each of the plurality of partial areas obtained by dividing the light receiving surface to a first area or a second area that images at a lower resolution than the first area;
In the partial region set as the first region, output of individual pixel signals from the pixels arranged along the first direction or simultaneous output of m1 (m1 is a positive integer) pixel signals is performed. In the partial area set as the second area, n1 (n1> m1) pixel signals are simultaneously output from the pixels arranged in the first direction to the image sensor. An image sensor driving device comprising: a control unit that controls the image sensor.   The imaging element driving device according to claim 1, wherein the number determined as the n1 increases as the number determined as the m1 decreases. The setting unit sets the plurality of partial areas as the first area, the second area, or a third area that captures images with a lower resolution than the second area,
The control unit causes the image sensor to simultaneously output s1 (s1> n1) pixel signals from the pixels arranged along the first direction in the partial region set as the third region. The image sensor driving apparatus according to claim 1 or 2, wherein The controller is
In the partial region set as the first region, the imaging device executes the output of individual pixel signals from the pixels arranged in the second direction or the simultaneous output of m2 pixel signals,
In the partial region set as the second region, the image sensor is configured to simultaneously output n2 (n2> m2) pixel signals from the pixels arranged in the second direction. The image sensor driving apparatus according to any one of claims 1 to 3.   The setting unit estimates a main subject in an entire image previously captured by the image sensor, sets the partial region in which the main subject is imaged as the first region, and images the main subject. The image sensor driving apparatus according to claim 1, wherein the partial area other than the partial area is set as the second area.   The setting unit estimates a moving body that is moving in the whole of a plurality of images previously captured by the imaging device, sets the partial region that images the moving body as the first region, 5. The image sensor driving apparatus according to claim 1, wherein the partial area other than the partial area captured by the moving body is set as the second area. 6. The setting unit
Estimating a moving body that is moving in the whole of a plurality of images previously captured by the image sensor,
Calculating the moving direction of the moving body;
The partial area that images the moving body and the partial area that is located in the moving direction from the partial area that images the moving body are set as the first area,
The partial area other than the partial area in the moving direction from the partial area where the moving body is imaged and the partial area where the moving body is imaged is set as the second area. The imaging element driving device according to any one of claims 1 to 4.   Each of the pixels is covered with any one of a plurality of types of color filters, and the control unit causes the pixels covered with the same color filter to simultaneously output the pixel signals. The imaging element driving device according to claim 1. Pixels are arranged along the first and second directions on the light receiving surface, and pixel signals generated by the respective pixels according to the amount of received light are individually or along the first direction and / or the second direction. An XY addressing imaging device main body capable of simultaneously outputting the pixel signals generated by the plurality of pixels;
A setting unit that sets each of the plurality of partial areas obtained by dividing the light receiving surface to a first area or a second area that images at a lower resolution than the first area;
In the partial region set as the first region, output of individual pixel signals from the pixels arranged along the first direction or simultaneous output of m1 (m1 is a positive integer) pixel signals is performed. In the partial area set as the second area, n1 (n1> m1) pixel signals are simultaneously output from the pixels arranged in the first direction to the image sensor. An image pickup device comprising: a control unit that controls the image pickup device.

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