Imaging device
By incorporating a pixel array, data length changing, and restoration sections, the imaging device addresses the large circuit size issue, achieving miniaturization and HDR support.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- SONY SEMICON SOLUTIONS CORP
- Filing Date
- 2024-11-15
- Publication Date
- 2026-05-27
AI Technical Summary
The circuit size of the image processing unit in imaging devices becomes large due to processing two image signals with different sensitivities, hindering miniaturization.
The imaging device includes a pixel array section, an image sensor, a data length changing section, a processing section, and a restoration section to modify and restore pixel signals, allowing for reduced circuit size and miniaturization.
The solution reduces the circuit size of the signal processing unit, enabling a more compact imaging device while maintaining image quality and supporting High Dynamic Range (HDR) capabilities.
Smart Images
Figure 2026087300000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to an imaging device.
Background Art
[0002] In an imaging device, an imaging device including an imaging element that performs imaging in two imaging modes, a high-sensitivity mode and a low-sensitivity mode, for HDR (High Dynamic Range) and generates two image signals with different sensitivities has been proposed (see, for example, Patent Document 1). In this imaging device, an image processing unit that processes each image signal is arranged. This image processing unit performs demosaicing processing and noise reduction processing.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] However, in the above prior art, since processing is performed on two image signals, there is a problem that the circuit size of the image processing unit becomes large and miniaturization of the imaging device becomes difficult.
[0005] Therefore, the present disclosure proposes an imaging device that can be miniaturized.
Means for Solving the Problems
[0006] The imaging device according to this disclosure includes a pixel array section configured with a plurality of pixels that generate pixel signals corresponding to incident light, an image sensor that converts the generated pixel signals into digital pixel signals and outputs them, a data length changing section that changes the data length of the output pixel signals, a processing section that processes the pixel signals whose data length has been changed, and a restoration section that restores the data length of the processed pixel signals. [Brief explanation of the drawing]
[0007] [Figure 1] This figure shows an example configuration of an imaging device according to the first embodiment of this disclosure. [Figure 2] This figure shows an example of the configuration of an image sensor according to the first embodiment of this disclosure. [Figure 3] This figure shows an example of the configuration of the pixel array portion according to the first embodiment of this disclosure. [Figure 4] This figure shows an example of the configuration of a signal processing unit according to the first embodiment of this disclosure. [Figure 5] This figure shows an example of the configuration of the processing unit according to the first embodiment of this disclosure. [Figure 6] This figure shows an example of data length modification according to the first embodiment of this disclosure. [Figure 7] This figure shows an example of restoration according to the first embodiment of this disclosure. [Figure 8] This figure shows an example of the configuration of a conventional imaging device. [Figure 9] This figure shows an example of the configuration of a signal processing unit according to the second embodiment of this disclosure. [Figure 10] This figure shows an example of data length modification according to the second embodiment of this disclosure. [Figure 11] This figure shows an example of restoration according to the second embodiment of this disclosure. [Figure 12] This figure shows a comparative example with a conventional imaging device. [Modes for carrying out the invention]
[0008] Embodiments of this disclosure will be described in detail below with reference to the drawings. The description will be in the following order. In each of the following embodiments, the same parts will be denoted by the same reference numerals to avoid redundant descriptions. 1. First Embodiment 2. Second Embodiment
[0009] (1. First Embodiment) <Configuration of the imaging device> Figure 1 is a diagram showing an example configuration of an imaging device according to the first embodiment of this disclosure. The figure is a block diagram representing an example configuration of the imaging device 1. The imaging device 1 is a device that captures an image of a subject and generates pixel signals that constitute the image of the subject. The generated pixel signals are output to an external device, etc. The imaging device 1 comprises an image sensor 10 and a signal processing unit 20. The image sensor 10 captures an image of a subject and generates pixel signals. For example, a CMOS (Complementary Metal Oxide Semiconductor) type image sensor can be applied to this image sensor 10. The image sensor 10 also outputs digital pixel signals. The signal processing unit 20 processes the digital pixel signals from the image sensor 10 and outputs the processed pixel signals. As will be described later, the signal processing unit 20 outputs a 12-bit wide pixel signal that supports HDR.
[0010] <Image sensor configuration> Figure 2 is a diagram showing an example configuration of an image sensor according to the first embodiment of this disclosure. The figure is a block diagram representing an example configuration of the image sensor 10. The image sensor 10 is a semiconductor element that generates pixel signals of a subject. The image sensor 10 comprises a pixel array section 11, a vertical drive section 12, a column signal processing section 13, and a control section 14.
[0011] The pixel array unit 11 is composed of a plurality of pixels 100 arranged therein. The pixel array unit 11 in the figure shows an example in which a plurality of pixels 100 are arranged in a two-dimensional matrix shape. Here, each pixel 100 includes a photoelectric conversion unit that performs photoelectric conversion of incident light, and generates a pixel signal of a subject based on the irradiated incident light. For example, a photodiode can be used for this photoelectric conversion unit. Signal lines 15 and 16 are wired to each pixel 100. The pixel 100 is controlled by a control signal transmitted through the signal line 15 to generate a pixel signal, and outputs the generated pixel signal via the signal line 16. Note that the signal line 15 is arranged for each row of the two-dimensional matrix shape and is commonly wired to the plurality of pixels 100 arranged in one row. The signal line 16 is arranged for each column of the two-dimensional matrix shape and is commonly wired to the plurality of pixels 100 arranged in one column.
[0012] The vertical drive unit 12 generates the control signals for the above-described pixels 100. The vertical drive unit 12 in the figure generates control signals for each row of the two-dimensional matrix of the pixel array unit 11 and sequentially outputs them via the signal line 15.
[0013] The column signal processing unit 13 processes the pixel signals generated by the pixels 100. The column signal processing unit 13 in the figure simultaneously processes the pixel signals from the plurality of pixels 100 arranged in one row of the pixel array unit 11 transmitted via the signal line 16. As this processing, for example, analog-to-digital conversion that converts the analog pixel signals generated by the pixels 100 into digital pixel signals and correlated double sampling (CDS) that removes the offset error of the pixel signals can be performed. The processed pixel signals are output to a circuit or the like outside the image pickup device 10.
[0014] The control unit 14 controls the vertical drive unit 12 and the column signal processing unit 13. The control unit 14 in the figure generates a control signal for controlling the vertical drive unit 12 and the column signal processing unit 13 based on data such as a clock and an operation mode input from an external circuit or the like. Next, the control unit 14 outputs the control signal via signal lines 17 and 18 to control the vertical drive unit 12 and the column signal processing unit 13 respectively.
[0015] An analog-to-digital converter is arranged in the column signal processing unit 13 in the figure and outputs a digital pixel signal. The data length of this digital pixel signal can be, for example, 12 bits or 14 bits. By setting the data length of the pixel signal to 12 bits or more, the dynamic range can be expanded and the aforementioned HDR can be supported.
[0016] [Configuration of Pixel Array Unit] FIG. 3 is a diagram showing a configuration example of a pixel array unit according to a first embodiment of the present disclosure. This figure is a plan view showing a configuration example of the pixel array unit 11. As described above, the pixel array unit 11 is configured by arranging pixels 100 in a two-dimensional matrix. The rectangles in the figure represent pixels 100. The "R", "G", and "B" attached to the pixels 100 in the figure represent the types of pixel signals generated by the respective pixels 100. The "R", "G", and "B" in the figure represent pixel signals corresponding to red light, green light, and blue light respectively. As shown in the figure, pixels 100 that generate the same type of pixel signal are arranged in two rows and two columns. The pixel array unit 11 in the figure has four pixels 100 arranged in two rows and two columns arranged in a Bayer array.
[0017] [Configuration of Signal Processing Unit] Figure 4 is a diagram showing an example configuration of a signal processing unit according to the first embodiment of this disclosure. The figure is a block diagram representing an example configuration of the signal processing unit 20. The signal processing unit 20 receives a 12-bit pixel signal from the image sensor 10. The signal processing unit 20 in the figure processes this pixel signal and outputs two 12-bit pixel signals, each having undergone different processing. The groups of rectangles labeled "R" etc. in the figure represent the arrangement of the pixel signals in each section. The pixel signals from the image sensor 10 are sequentially input in an arrangement that follows the order of the pixels 100 in the pixel array section 11 shown in Figure 3. One of the pixel signals output from the signal processing unit 20 is output with four pixel signals in a 2x2 arrangement corresponding to the Bayer array. The other pixel signal output from the signal processing unit 20 is output in the same format as the pixel signal output from the image sensor 10.
[0018] The signal processing unit 20 comprises a processing unit 210, a data length modification unit 220, a processing unit 230, a restoration unit 240, and an interface unit 250. In the figure, the "interface unit" is denoted as "IF".
[0019] The processing unit 210 processes 12-bit pixel signals. The processing unit 210 outputs the processed pixel signals to the data length modification unit 220 and the interface unit 250. The image based on the pixel signals output to the interface unit 250 is an image that has not undergone the processing (remosaic processing) of the processing unit 230 described later, and is referred to as RAW data. This RAW data can be used, for example, for AI learning. Details of the configuration of the processing unit 210 will be described later. Note that the processing unit 210 is an example of the "second processing unit" in this disclosure.
[0020] The data length modification unit 220 modifies the data length of the input pixel signal. The data length modification unit 220 in the diagram modifies a 12-bit wide pixel signal into a 10-bit wide pixel signal. Furthermore, the data length modification unit 220 generates two 10-bit pixel signals and outputs them to the processing unit 230. Details of the data length modification performed by the data length modification unit 220 will be described later.
[0021] The processing unit 230 processes pixel signals whose data length has been changed. This processing unit 230 can, for example, perform remosaic processing. This remosaic processing is the process of converting an image consisting of an array of multiple pixel signals into an array of different pixel signals. Specifically, remosaic processing is the process of converting an image in which four blocks of pixel signals arranged in a 2x2 grid, as shown in the figure, are arranged in an order corresponding to a Bayer array into an image arranged in a Bayer array. The processing unit 230 outputs two processed 10-bit pixel signals to the restoration unit 240. Note that if remosaic processing is performed on a 12-bit pixel signal, the circuit size of the processing unit 230 will increase. The processing unit 230 in the figure can be made into a relatively small circuit by configuring it to process 10-bit pixel signals. The processing unit 230 performs the 10-bit pixel signal remosaic processing twice using time division multiplexing.
[0022] The restoration unit 240 restores the data length of the pixel signal. The restoration unit 240 restores the data length of a 10-bit wide pixel signal to its original 12-bit width. In the figure, the restoration unit 240 restores the 12-bit wide data length by combining two 10-bit wide pixel signals. The restoration unit 240 outputs the pixel signal with the restored data length to the interface unit 250. Details of the data length restoration by the restoration unit 240 will be described later.
[0023] The interface unit 250 communicates with external devices. Furthermore, this interface unit 250 can convert the input pixel signal into a signal conforming to the MIPI (Mobile Industry Processor Interface) (registered trademark) standard and output it to external devices. The interface unit 250 converts and outputs the 12-bit pixel signal output from the restoration unit 240 and the 12-bit pixel signal (RAW data) output from the processing unit 210.
[0024] The processing unit 210, processing unit 230, and restoration unit 240 each use a working memory to hold one row of pixel signals. Processing unit 210 uses 12-bit memory. Processing unit 230 and restoration unit 240 each use two 10-bit memories.
[0025] [Configuration of the processing area] Figure 5 is a diagram showing an example configuration of a processing unit according to the first embodiment of the present disclosure. The same figure is a block diagram showing an example configuration of the processing unit 210. The processing unit 210 comprises a sorting processing unit 211, an adjustment unit 212, and a defect correction unit 213.
[0026] The reordering processing unit 211 rearranges the pixel signals. As described above, the image sensor 10 reads out the pixel signals of one row of pixels 100 for each row of the pixel array unit 11, performs analog-to-digital conversion, and outputs them sequentially. However, depending on the image sensor 10, the order in which the pixel signals are read out may differ from the order in which the pixels 100 are arranged in the pixel array unit 11. In such cases, the reordering processing unit 211 rearranges the pixel signals and outputs them in the same order as the arrangement of the pixels 100 in the pixel array unit 11.
[0027] The adjustment unit 212 adjusts the pixel signal. This adjustment includes, for example, black level adjustment and sensitivity adjustment.
[0028] The defect correction unit 213 compensates for the pixel signal that has been lost due to a defect in the pixel 100.
[0029] [Change data length] Figure 6 is a diagram showing an example of data length modification according to the first embodiment of this disclosure. The diagram shows an example of the data length modification process in the data length modification unit 220. The data length modification unit 220 generates an upper-order pixel signal consisting of multiple bits from the most significant bit of a 12-bit wide pixel signal, excluding at least the least significant bit, and moving in a downward direction from the most significant bit. The data length modification unit 220 also generates a lower-order pixel signal consisting of multiple bits from the least significant bit of a 12-bit wide pixel signal, excluding at least the most significant bit, and moving in a downward direction from the least significant bit. In the example shown in the diagram, the data length modification unit 220 extracts the upper 10 bits of the 12-bit wide pixel signal to generate a 10-bit wide pixel signal. This pixel signal becomes a low-sensitivity pixel signal. The data length modification unit 220 also extracts the lower 10 bits of the 12-bit wide pixel signal to generate a 10-bit wide pixel signal. This pixel signal becomes a high-sensitivity pixel signal. In this way, the data length modification unit 220 generates low-sensitivity and high-sensitivity pixel signals with shortened data lengths. In the following explanation, the upper-level pixel signal and the lower-level pixel signal may be referred to as the low-sensitivity pixel signal and the high-sensitivity pixel signal, respectively.
[0030] [Restore] Figure 7 is a diagram showing an example of restoration according to the first embodiment of this disclosure. The diagram illustrates the restoration process in the restoration unit 240. The restoration unit 240 extends the data length by combining the low-sensitivity pixel signal and the high-sensitivity pixel signal. Specifically, the restoration unit 240 extends the data length by mixing the low-sensitivity pixel signal and the high-sensitivity pixel signal, which have been shifted by the number of missing bits. As shown in the diagram, the data length of the low-sensitivity pixel signal is extended by adding two bits of value "0" to the low-sensitivity pixel signal. Next, this pixel signal and the high-sensitivity pixel signal are mixed according to the formula shown in the diagram to generate a 12-bit wide pixel signal. Here, α in the diagram represents the mixing ratio. This mixing method is called α blending.
[0031] The mixing ratio α can be adjusted according to the pixel signal value. The restoration unit 240 can increase the ratio of the upper pixel signal when the pixel signal value is large, and increase the ratio of the lower pixel signal when the pixel signal value is small.
[0032] [Comparison with conventional technology] Figure 8 shows an example of the configuration of a conventional imaging device. This figure is a block diagram representing an example of the configuration of a conventional imaging device 1, which serves as a comparative example. The image sensor 10 in this figure is assumed to be an image sensor that outputs 10-bit low-sensitivity pixel signals and 10-bit high-sensitivity pixel signals. The signal processing unit 20 outputs a 12-bit wide pixel signal, similar to the signal processing unit 20 in Figure 4.
[0033] The signal processing unit 20 comprises a processing unit 210, a processing unit 230, combining units 290a and 290b, and an interface unit 250. The combining unit 290a combines two 10-bit wide pixel signals output from the processing unit 230 to generate a 12-bit wide pixel signal. The combining unit 290b also combines two 10-bit wide pixel signals output from the processing unit 210 to generate a 12-bit wide pixel signal. The combining units 290a and 290b can perform the same processing as the restoration shown in Figure 7. The processing units 210, 230, and combining units 290a and 290b in the same figure use two 10-bit working memories.
[0034] The conventional signal processing unit 20 processes the two 10-bit pixel signals as they are, resulting in a larger memory size in each section. Furthermore, a combining unit 290b is required to generate 12-bit wide pixel signals that become RAW data. Therefore, the conventional signal processing unit 20 has a larger circuit size than the signal processing unit 20 shown in Figure 4. However, in the conventional signal processing unit 20, if the 12-bit pixel signals from the image sensor 10 are input to the processing unit 230 for processing, the memory size is smaller compared to the processing unit 230 shown in Figure 4. However, the remosaic processing circuit of the processing unit 230 increases in size proportionally to the data length, leading to increased power consumption.
[0035] The configuration of the imaging device 1 in the embodiment of this disclosure is not limited to this example. For example, an image sensor 10 that generates pixel signals with a bit width greater than 12, for example, 14 bits wide, can also be used. In this case, the signal processing unit 20 processes the 14-bit wide pixel signal. Specifically, the processing unit 210 of the signal processing unit 20 processes the 14-bit wide pixel signal. The data length changing unit 220 changes the data length of the 14-bit wide pixel signal to two 10-bit wide pixel signals. The restoration unit 240 restores the 14-bit wide pixel signal from the two 10-bit wide pixel signals.
[0036] As described above, the imaging device 1 of the first embodiment of this disclosure uses an image sensor 10 that generates a pixel signal with a data length corresponding to HDR, and includes a signal processing unit 20 that processes the pixel signal. The signal processing unit 20 performs processing that uses the input pixel signal as is, as with the processing unit 210, and also inputs a pixel signal with a modified data length to the processing unit 230, whose processing circuit size increases according to the data length of the pixel signal, and performs processing. This makes it possible to reduce the circuit size of the signal processing unit 20 and make the imaging device 1 more compact.
[0037] (2. Second Embodiment) In the first embodiment described above, the signal processing unit 20 of the imaging device 1 generated the upper pixel signal and the lower pixel signal using a data length changing unit 220. In contrast, the signal processing unit 20 of the imaging device 1 of the second embodiment of this disclosure differs from the first embodiment described above in that it generates either the upper pixel signal or the lower pixel signal.
[0038] <Configuration of the imaging device> Figure 9 is a diagram showing an example configuration of a signal processing unit according to a second embodiment of the present disclosure. This figure is a block diagram showing an example configuration of the signal processing unit 20, similar to Figure 4. In this figure, the working memory is omitted. The signal processing unit 20 in this figure differs from the signal processing unit 20 in Figure 4 in that it includes a data length changing unit 260 instead of a data length changing unit 220, and a restoration unit 280 is placed instead of a restoration unit 240. The processing unit 210 in this figure includes an adjustment unit 212 and a defect correction unit 213, as described in Figure 5, and processes the pixel signal whose data length has been changed by the data length changing unit 260. On the other hand, the sorting processing unit 211, which was included in the processing unit 210 in Figure 5, is placed before the data length changing unit 260.
[0039] The 12-bit wide pixel signals from the image sensor 10 are input to the reordering processing unit 211. The reordering processing unit 211 inputs the reordered pixel signals to the data length changing unit 260.
[0040] The data length modification unit 260 generates and outputs either a 10-bit wide upper pixel signal or a 10-bit wide lower pixel signal, obtained by modifying the data length from a 12-bit wide pixel signal. At this time, the data length modification unit 260 further outputs identification information to distinguish between the upper and lower pixel signals. "Flg" in the figure represents this identification information. Details of the data length modification in the data length modification unit 260 will be described later.
[0041] Processing unit 210 and processing unit 230 each perform processing on the 10-bit wide pixel signal.
[0042] The restoration unit 280 restores the data length of either the upper-order pixel signal or the lower-order pixel signal of the 10-bit width, and outputs a 12-bit width pixel signal. Details of the restoration process in the restoration unit 280 will be described later.
[0043] The interface unit 250 converts the pixel signals from the restoration unit 280 into signals conforming to the MIPI (registered trademark) standard and outputs them to external devices, etc.
[0044] [Change data length] Figure 10 is a diagram showing an example of data length modification according to the second embodiment of this disclosure. The diagram illustrates the data length modification process in the data length modification unit 260. Similar to the process in Figure 6, the data length modification unit 260 generates a higher-order pixel signal and a lower-order pixel signal from a 12-bit wide pixel signal. Next, the data length modification unit 260 selects and outputs either the higher-order pixel signal (low-sensitivity pixel signal) or the lower-order pixel signal (high-sensitivity pixel signal). The data length modification unit 260 can make this selection, for example, based on the pixel signal value. Specifically, the data length modification unit 260 selects the higher-order pixel signal when the pixel signal value is relatively large, and selects the lower-order pixel signal when the pixel signal value is relatively small. This is because information near the most significant bit is not necessary for pixel signals in low-light environments, and the contribution of information near the least significant bit is not large for pixel signals of high-luminance subjects.
[0045] The data length modification unit 260 adds identification information corresponding to the selected pixel signal to the pixel signal and outputs it. In the figure, one bit of identification information "Flg" is added. In the example of identification information in the figure, a value of "0" represents the upper pixel signal (low sensitivity pixel signal), and a value of "1" represents the lower pixel signal (high sensitivity pixel signal).
[0046] [Restore] Figure 11 is a diagram showing an example of restoration according to the second embodiment of this disclosure. The diagram illustrates the restoration process in the restoration unit 280. The restoration unit 280 determines whether it is a higher-order pixel signal (low-sensitivity pixel signal) or a lower-order pixel signal (high-sensitivity pixel signal) based on identification information. The restoration unit 280 then performs restoration by adding missing bits of data to the higher-order and lower-order pixel signals to extend the data length.
[0047] The restoration unit 280 adds the missing 2 bits of data to the least significant bit of the upper-order pixel signal. The added data is randomly selected from values "0" and "1". The restoration unit 280 also adds the missing 2 bits of data to the most significant bit of the lower-order pixel signal. The added data is value "0". In this way, the restoration unit 280 restores the data length for either the upper-order or lower-order pixel signal.
[0048] [Comparison with conventional technology] Figure 12 shows a comparison with a conventional imaging device. The upper part of the figure is a timing diagram representing the processing in the signal processing unit 20 described in Figure 8. The processing in the signal processing unit 20 is performed at timings based on the synchronization signal. In the conventional signal processing unit 20, the processing of 10-bit wide pixel signals (low sensitivity) and 12-bit pixel signals and the processing of 10-bit pixel signals (high sensitivity) are performed in a time-division manner.
[0049] The lower part of the figure is a timing diagram showing the processing in the signal processing unit 20 of Figure 9. In the signal processing unit 20 of Figure 9, only 10-bit wide pixel signals and identification information are processed. The memory size required for processing can be reduced by half. Furthermore, since processing of 12-bit pixel signals is unnecessary, the circuit size of the processing circuit in the signal processing unit 20 of Figure 9 can be reduced. In addition, since time-division multiplexing is unnecessary, the signal processing unit 20 of Figure 9 can reduce power consumption and improve the frame frequency.
[0050] The configuration of the imaging device 1 other than that described above is the same as that of the imaging device 1 in the first embodiment of this disclosure, so a description will be omitted.
[0051] Thus, in the imaging device 1 of the second embodiment of this disclosure, the data length changing unit 260 of the signal processing unit 20 selects either the upper pixel signal or the lower pixel signal and outputs it to the subsequent processing units (processing unit 210 and processing unit 230). This makes it possible to further reduce the circuit size of the signal processing unit 20 and to miniaturize the imaging device 1.
[0052] <Effects> The imaging device comprises a pixel array section composed of multiple pixels arranged to generate pixel signals corresponding to incident light, an image sensor that converts the generated pixel signals into digital pixel signals and outputs them, a data length modification section that changes the data length of the output pixel signals, a processing section that processes the pixel signals whose data length has been modified, and a restoration section that restores the data length of the processed pixel signals. This results in the pixel signals whose data length has been modified being processed by the processing section. The circuit size of the processing section can be reduced.
[0053] Furthermore, the processing unit performs a process to convert an image consisting of multiple arrays of pixel signals into a different array of pixel signals. For processes where the circuit size increases according to the data length, pixel signals with changed data lengths can be applied.
[0054] Furthermore, the system may have a second processing unit that performs a different process on the output pixel signal than the processing unit described above, and the data length changing unit may change the data length of the pixel signal processed by the second processing unit. This allows the pixel signal before the data length change to be applied to the second processing unit.
[0055] Furthermore, the data length changing unit changes the data length of the pixel signal by generating an upper-order pixel signal consisting of multiple bits from the most significant bit of the pixel signal, excluding the least significant bit, and a lower-order pixel signal consisting of multiple bits from the least significant bit of the pixel signal, excluding the most significant bit, and the processing unit performs the above processing on the upper-order pixel signal and the lower-order pixel signal. This makes it possible to maintain the amount of information in the pixel signal before the data length change.
[0056] Alternatively, the restoration unit may restore the data by extending the data length while combining the upper-side pixel signal and the lower-side pixel signal. This makes it possible to maintain the amount of information in the pixel signal before the data length change.
[0057] Furthermore, the restoration unit may combine the upper and lower pixel signals by mixing the upper and lower pixel signals, which have been shifted by the missing number of bits. This makes it possible to restore the original data length of the pixel signal.
[0058] Furthermore, the data length modification unit modifies the data length of the pixel signal by generating either an upper-order pixel signal consisting of multiple bits excluding the least significant bit that are consecutive from the most significant bit of the pixel signal downwards, or a lower-order pixel signal consisting of multiple bits excluding the most significant bit that are consecutive from the least significant bit of the pixel signal downwards. The processing unit then performs the above processing on either the upper-order pixel signal or the lower-order pixel signal. This reduces the circuit size of the subsequent processing unit.
[0059] Furthermore, the data length modification unit may generate identification information for identifying the upper-level pixel signal and the lower-level pixel signal. This allows for proper restoration of the data length of the pixel signal.
[0060] Furthermore, the restoration unit may restore the data length for either the upper pixel signal or the lower pixel signal. This allows the processing to be limited to only the necessary steps.
[0061] Furthermore, the restoration unit may restore the data by adding missing bits of data to the upper and lower pixel signals to extend the data length. This allows the original data length of the pixel signal to be restored.
[0062] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.
[0063] Furthermore, this technology can also be configured as follows. (1) An image sensor comprising a pixel array section composed of multiple pixels arranged to generate pixel signals corresponding to incident light, and which converts the generated pixel signals into digital pixel signals and outputs them, A data length changing unit that changes the data length of the output pixel signal, A processing unit that processes the pixel signal whose data length has been changed, A restoration unit that restores the data length of the processed pixel signal. An imaging device having (2) The imaging apparatus according to (1), wherein the processing unit performs a process of converting an image consisting of a plurality of the arrays of pixel signals into a different array of pixel signals. (3) The system further includes a second processing unit that performs a different processing on the output pixel signal than the processing unit, The data length changing unit changes the data length of the pixel signal processed by the second processing unit. The imaging device described in (1) or (2) above. (4) The data length changing unit changes the data length of the pixel signal by generating an upper-order pixel signal consisting of multiple bits from the most significant bit of the pixel signal in the downward direction, excluding at least the least significant bit, and a lower-order pixel signal consisting of multiple bits from the least significant bit of the pixel signal in the upward direction, excluding at least the most significant bit. The processing unit performs the processing on the upper pixel signal and the lower pixel signal. An imaging device as described in any of (1) to (3) above. (5) The imaging apparatus according to (4) above, wherein the restoration unit restores the data by expanding the data length while combining the upper pixel signal and the lower pixel signal. (6) The imaging apparatus according to (5), wherein the restoration unit combines the upper pixel signal and the lower pixel signal by mixing the upper pixel signal and the lower pixel signal which have been shifted by the number of missing bits. (7) The data length changing unit changes the data length of the pixel signal by generating either an upper-order pixel signal consisting of multiple bits from the most significant bit of the pixel signal in a downward direction, excluding at least the least significant bit, or a lower-order pixel signal consisting of multiple bits from the least significant bit of the pixel signal in a downward direction, excluding at least the most significant bit. The processing unit performs the processing on either the upper pixel signal or the lower pixel signal. The imaging device described in (1) above. (8) The imaging apparatus according to (7), wherein the data length changing unit further generates identification information for identifying the upper pixel signal and the lower pixel signal. (9) The imaging apparatus according to (7) or (8), wherein the restoration unit restores the data length for either the upper pixel signal or the lower pixel signal. (10) The imaging apparatus according to (9), wherein the restoration unit restores the data by adding missing bit data to the upper pixel signal and the lower pixel signal to extend the data length. [Explanation of Symbols]
[0064] 1. Imaging device 10 Image sensor 20 Signal Processing Unit 100 pixels 210, 230 Processing Unit 220, 260 Data length change section 240, 280 Restoration section
Claims
1. An image sensor comprising a pixel array section composed of multiple pixels arranged to generate pixel signals corresponding to incident light, and which converts the generated pixel signals into digital pixel signals and outputs them, A data length changing unit that changes the data length of the output pixel signal, A processing unit that processes the pixel signal whose data length has been changed, A restoration unit that restores the data length of the processed pixel signal. An imaging device having
2. The imaging apparatus according to claim 1, wherein the processing unit performs a process to convert an image consisting of a plurality of the arrays of pixel signals into a different array of pixel signals.
3. The system further includes a second processing unit that performs a different process on the output pixel signal than the processing unit, The data length changing unit changes the data length of the pixel signal processed by the second processing unit. The imaging apparatus according to claim 1.
4. The data length changing unit changes the data length of the pixel signal by generating an upper-order pixel signal consisting of multiple bits from the most significant bit of the pixel signal in the downward direction, excluding at least the least significant bit, and a lower-order pixel signal consisting of multiple bits from the least significant bit of the pixel signal in the upward direction, excluding at least the most significant bit. The processing unit performs the processing on the upper pixel signal and the lower pixel signal. The imaging apparatus according to claim 1.
5. The imaging apparatus according to claim 4, wherein the restoration unit restores the data by expanding the data length while combining the upper pixel signal and the lower pixel signal.
6. The imaging apparatus according to claim 5, wherein the restoration unit synthesizes the upper pixel signal and the lower pixel signal by mixing the upper pixel signal and the lower pixel signal which have been shifted by the number of missing bits.
7. The data length changing unit changes the data length of the pixel signal by generating either an upper-order pixel signal consisting of multiple bits from the most significant bit of the pixel signal in a downward direction, excluding at least the least significant bit, or a lower-order pixel signal consisting of multiple bits from the least significant bit of the pixel signal in a downward direction, excluding at least the most significant bit. The processing unit performs the processing on either the upper pixel signal or the lower pixel signal. The imaging apparatus according to claim 1.
8. The imaging apparatus according to claim 7, wherein the data length changing unit further generates identification information for identifying the upper pixel signal and the lower pixel signal.
9. The imaging apparatus according to claim 7, wherein the restoration unit restores the data length for either the upper pixel signal or the lower pixel signal.
10. The imaging apparatus according to claim 9, wherein the restoration unit restores the data by adding missing bit data to the upper pixel signal and the lower pixel signal to extend the data length.