CN106303311B - Output method of pixel sensitivity value - Google Patents

Abstract

The invention provides an output method of a pixel photosensitive value. The pixel photosensitive value output method of the invention adds short exposure with the exposure time shorter than the normal exposure time in addition to the normal exposure, effectively eliminates the fixed mode noise introduced by the pixel unit reading circuit and the time sequence by differential output of the normal exposure and the short exposure of each row of pixel units, and further improves the image quality.

Description

Output method of pixel sensitivity value

technical field

The present invention relates to the field of image sensors, and in particular, to a method for outputting pixel photosensitive values.

Background technique

At present, image sensors mainly include CCD image sensors (Charged Coupled Device) and CMOS image sensors (CMOS Imaging Sensor, CIS). Compared with CDD image sensors, CMOS image sensors have the advantages of low power consumption, low noise, wide dynamic range, small size, and low cost. Therefore, CMOS image sensors have gradually become a research and development hotspot in this technical field.

The analog-to-digital converter (Analog-to-Digital Convert, ADC) is an important part of the CMOS image sensor, which is used to convert the analog signal generated by each pixel unit into a digital signal, and is the interface between the analog circuit and the digital circuit.

Existing CMOS image sensors mainly use three kinds of ADCs, namely: chip-level ADC, column-parallel ADC and pixel-level ADC. Chip-level ADC means that the entire chip has only one ADC, and the analog output generated by each pixel must be sequentially converted by this ADC for analog-to-digital conversion. Therefore, this ADC occupies a small area, but at the same time, the conversion speed is slow, and it is only suitable for pixels. Applications where the array is small and does not require high CIS speed. Pixel-level ADC means that each pixel or every few pixels share an ADC. This kind of ADC has high signal-to-noise ratio, low power consumption, and low speed requirements of the ADC, but has low pixel fill factor and complex layout design, which cannot be industrialized at present. The column-parallel ADC is a compromise between the chip-level ADC and the pixel-level ADC. It uses one ADC for each column of pixels. The ADC in each column is only responsible for processing the data of this column, and the ADCs in each column work at the same time. This semi-parallel processing also Taking advantage of chip-level ADC and pixel-level ADC can greatly improve the conversion efficiency, and has a wide application prospect in the development of CIS in the future.

The wide application of high-pixel image sensors puts forward higher requirements for image quality, and Fixed Pattern Noise (FPN) is the main factor affecting image quality. In order to eliminate the FPN introduced by the readout circuit of the pixel photosensitive unit, for the image sensor that uses the column-parallel ADC as the readout circuit, the Correlated Double Sampling (CDS) technology is widely used, including analog correlated double sampling and digital correlated double sampling. sampling.

Among them, the analog correlated double sampling is to sample the reset voltage and the photosensitive voltage of the pixel unit respectively through two capacitors, and realize the digitization of the difference between the pixel photosensitive voltage and the reset voltage through the analog circuit ADC. However, in order to achieve high enough accuracy, a large sampling capacitor value is usually required, so the design cost is high.

The Chinese patent application with the publication number CN 103686004A discloses a pixel photosensitive value output method using digital correlated double sampling. The reset voltage and the photosensitive voltage are compared, and the difference calculation between the pixel photosensitive voltage and the reset voltage is realized in the digital system, so as to obtain the pixel photosensitive value. However, although this method can eliminate the FPN introduced by the readout circuit, it still cannot effectively eliminate the FPN introduced by the timing.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide an output method of pixel photosensitive value, which can eliminate the fixed pattern noise introduced by the pixel unit readout circuit and timing, and further improve the image quality.

In order to solve the above problems, the present invention provides a method for outputting the photosensitive value of a pixel, which includes the following steps:

A. After the first reset, each column of pixel units in the pixel array is exposed for the first time, and the first exposure time is the normal exposure time, and the first photosensitive voltage of each column of pixel units is output;

The ramp signal is generated by the ramp generating circuit, the ramp signal and the first photosensitive voltage are compared by the comparator, and the first photosensitive count value of each column of pixel units is obtained by the counter;

b. After the second reset, each column of pixel units in the pixel array is exposed for the second time, and the second exposure time is less than the normal exposure time, and the second photosensitive voltage of each column of pixel units is output;

The ramp signal is generated by the ramp generating circuit, the ramp signal and the second photosensitive voltage are compared by the comparator, and the second photosensitive count value of each column of pixel units is obtained by the counter;

c. The difference between the first light-sensing count value and the second light-sensing count value of each column of pixel units is calculated to obtain the pixel light-sensing value of each column of pixel units.

Preferably, the output method of the pixel photosensitive value includes the following steps:

A1. After the first reset, each column of pixel units in the pixel array is exposed for the first time, and the first exposure time is the normal exposure time, and the first photosensitive voltage of each column of pixel units is output;

The ramp generating circuit generates the first ramp signal, and the counter starts to count from zero;

The comparator compares the first ramp signal voltage with the first photosensitive voltage of each column of pixel units, and when the first ramp signal voltage exceeds the first photosensitive voltage of each column of pixel units, the counter obtains the first photosensitive voltage of each column of pixel units Photosensitive count value VSN;

B1. After the second reset, each column of pixel units in the pixel array is exposed for the second time, and the second exposure time is less than the normal exposure time, and the second photosensitive voltage of each column of pixel units is output;

The ramp generating circuit generates a second ramp signal, and the counter restarts to count from zero;

The comparator compares the second ramp signal voltage with the second photosensitive voltage of each column of pixel units, and when the second ramp signal voltage exceeds the second photosensitive voltage of each column of pixel units, the counter obtains the second photosensitive voltage of each column of pixel units Photosensitive count value VSZ;

C1. The difference between the first light-sensing count value VSN and the second light-sensing count value VSZ of each column of pixel units is calculated to obtain the pixel light-sensing value VSN-VSZ of each column of pixel units.

Preferably, the output method of the pixel photosensitive value includes the following steps:

A2. For the first reset, the first reset voltage of each column of pixel units is generated;

The ramp generating circuit generates the first ramp signal, and the counter starts to count from zero;

The comparator compares the first ramp signal voltage with the first reset voltage of each column of pixel units, and when the first ramp signal voltage exceeds the first reset voltage of each column of pixel units, the counter obtains the first reset voltage of each column of pixel units reset count value VRN;

Each column of pixel units is exposed for the first time, and the first exposure time is a normal exposure time, and the first photosensitive voltage of each column of pixel units is output;

The ramp generating circuit generates a second ramp signal, and the counter restarts to count from zero;

The comparator compares the second ramp signal voltage with the first photosensitive voltage of each column of pixel units, and when the second ramp signal voltage exceeds the first photosensitive voltage of each column of pixel units, the counter obtains the first photosensitive voltage of each column of pixel units Photosensitive count value VSN;

B2. The second reset generates a second reset voltage of each column of pixel units;

The ramp generating circuit generates a third ramp signal, and the counter restarts to count from zero;

The comparator compares the third ramp signal voltage with the second reset voltage of each column of pixel units, and when the third ramp signal voltage exceeds the second reset voltage of each column of pixel units, the counter obtains the second reset voltage of each column of pixel units reset count value VRZ;

Each column of pixel units is exposed for the second time, and the second exposure time is shorter than the normal exposure time, and the second photosensitive voltage of each column of pixel units is output;

The ramp generating circuit generates the fourth ramp signal, and the counter restarts to count from zero;

The comparator compares the fourth ramp signal voltage with the second photosensitive voltage of each column of pixel units, and when the fourth ramp signal voltage exceeds the second photosensitive voltage of each column of pixel units, the counter obtains the second photosensitive voltage of each column of pixel units Photosensitive count value VSZ;

C2. Calculate the difference between the first photosensitive count value VSN and the first reset count value VRN of each column of pixel units, to obtain the first exposure count difference value VSN-VRN;

Calculate the difference between the second photosensitive count value VSZ and the second reset count value VRZ of each column of pixel units, to obtain the second exposure count difference value VSZ-VRZ;

Calculate the difference between the first exposure count difference VSN-VRN and the second exposure count difference VSZ-VRZ of each column of pixel units to obtain the pixel sensitivity value of each column of pixel units (VSN-VRN)-(VSZ-VRZ ).

Preferably, the method for outputting the pixel photosensitive value further includes: repeating the step B to obtain a plurality of photosensitive count values with the exposure time of each column of pixel units being less than the normal exposure time, and respectively for the first photosensitive pixel of each column of pixel units. The difference between the count value and a plurality of light-sensing count values whose exposure time is less than the normal exposure time is calculated to obtain the pixel light-sensing value of each column of pixel units.

Preferably, the method for outputting the photosensitive value of the pixel further includes: adjusting the second exposure time according to the input offset voltage of different comparators.

Preferably, the first ramp signal, the second ramp signal, the third ramp signal, and the fourth ramp signal are upward ramp signals or downward ramp signals.

Preferably, the method for outputting the light-sensing value of a pixel further comprises: recording the first reset count value, the second reset count value, the first light-sensitivity count value, and the second light-sensitivity count value through a memory.

The pixel photosensitive value output method of the present invention adds a short exposure with an exposure time shorter than the normal exposure time in addition to the normal exposure, and effectively eliminates the pixel unit readout through the differential output of the normal exposure and short exposure of each column of pixel units. The fixed pattern noise introduced by the output circuit and timing further improves the image quality.

Description of drawings

Fig. 1 is the flow chart of the pixel photosensitive value output method of the present invention;

FIG. 2 is a timing diagram of a method for outputting a pixel photosensitive value according to Embodiment 1 of the present invention;

FIG. 3 is a timing chart of a method for outputting light-sensitivity values of pixels according to Embodiment 2 of the present invention.

Detailed ways

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar promotions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific implementation disclosed below.

Next, the present invention is described in detail by using schematic diagrams. When describing the embodiments of the present invention in detail, for the convenience of description, the schematic diagrams are only examples, which should not limit the protection scope of the present invention.

As shown in FIG. 1 , the present invention provides a method for outputting the photosensitive value of a pixel, which includes the following steps:

A. After the first reset, each column of pixel units in the pixel array is exposed for the first time, and the first exposure time is the normal exposure time, and the first photosensitive voltage of each column of pixel units is output;

The ramp signal is generated by the ramp generating circuit, the ramp signal and the first photosensitive voltage are compared by the comparator, and the first photosensitive count value of each column of pixel units is obtained by the counter;

b. After the second reset, each column of pixel units in the pixel array is exposed for the second time, and the second exposure time is less than the normal exposure time, and the second photosensitive voltage of each column of pixel units is output;

The ramp signal is generated by the ramp generating circuit, the ramp signal and the second photosensitive voltage are compared by the comparator, and the second photosensitive count value of each column of pixel units is obtained by the counter;

c. The difference between the first light-sensing count value and the second light-sensing count value of each column of pixel units is calculated to obtain the pixel light-sensing value of each column of pixel units.

The method for outputting the pixel sensitivity value of the present invention will be specifically described below with reference to specific embodiments.

Example 1

FIG. 2 is a timing chart of a method for outputting light-sensitivity values of pixels according to Embodiment 1 of the present invention.

As shown in FIG. 2 , the RST signal is the reset control signal of the pixel photosensitive unit, the TX signal is the exposure transmission control signal of the pixel photosensitive unit, and the ramp is the ramp signal generated by the ramp generation circuit.

First, the RST signal controls each column of pixel units to reset for the first time. After that, the TX signal controls each column of pixel units to be exposed for the first time. The first exposure time T1 is the normal exposure time, and each column of pixel units outputs the first photosensitive voltage. The ramp generating circuit generates a first ramp signal, and the counter starts to count from zero. As the first ramp signal gradually increases, the voltage difference between the first ramp signal and the first photosensitive voltage gradually shrinks. When the first ramp signal exceeds the first photosensitive voltage, the comparator is triggered to turn over, and the count value of the counter at this time is the first photosensitive count value VSN of each column of pixel units. Preferably, the first photosensitive count value VSN can also be recorded through a memory.

Next, the RST signal controls each column of pixel units to reset for the second time, and then, the TX signal controls each column of pixel units to be exposed for the second time, and the second exposure time T2 is less than the normal exposure time (that is, the second exposure is the exposure time “Short exposure” shorter than the normal exposure time), each column of pixel units respectively outputs a second photosensitive voltage. Preferably, the second exposure time T2 can be adjusted according to the input offset voltage of different comparators. The ramp generating circuit generates a second ramp signal, and the counter starts counting from zero again. As the second ramp signal gradually increases, the voltage difference between the second ramp signal and the second photosensitive voltage gradually shrinks. When the second ramp signal exceeds the second photosensitive voltage, the comparator is triggered to turn over, and the count value of the counter at this time is the second photosensitive count value VSZ of each column of pixel units. Preferably, the second photosensitive count value VSZ can also be recorded through a memory.

Finally, the difference between the first photosensitive count value VSN and the second photosensitive count value VSZ of each column of pixel units is calculated to obtain the pixel photosensitive value VSN-VSZ of each column of pixel units, thereby eliminating the pixel unit readout circuit and timing. Pattern noise to improve image quality.

Those skilled in the art can understand that, in this embodiment, the first ramp signal and the second ramp signal are both upward ramp signals (the slope is positive). The second ramp signal can also be a downward ramp signal (the slope is negative), and the legend is only a schematic diagram.

Embodiment 2

FIG. 3 is a timing diagram of a method for outputting light-sensitivity values of pixels according to Embodiment 2 of the present invention.

As shown in FIG. 3 , the RST signal is the reset control signal of the pixel photosensitive unit, the TX signal is the exposure transmission control signal of the pixel photosensitive unit, and the ramp is the ramp signal generated by the ramp generation circuit.

First, the RST signal controls each column of pixel units to reset for the first time, and each column of pixel units outputs a first reset voltage respectively. The ramp generating circuit generates a first ramp signal, and the counter starts to count from zero. As the first ramp signal gradually increases, the voltage difference between the first ramp signal and the first reset voltage gradually shrinks. When the first ramp signal exceeds the first reset voltage, the comparator is triggered to turn over, and the count value of the counter at this time is the first reset count value VRN of each column of pixel units. Preferably, the first reset count value VRN may also be recorded through a memory.

After that, the TX signal controls the first exposure of the pixel units in each column, the first exposure time T1 is the normal exposure time, and the pixel units in each column output the first photosensitive voltage respectively. The ramp generating circuit generates the second ramp signal, and the counter restarts to count from zero. As the second ramp signal gradually increases, the voltage difference between the second ramp signal and the first photosensitive voltage gradually decreases, and when the second ramp signal exceeds the first photosensitive voltage, triggering the The comparator is turned over, and the count value of the counter at this time is the first photosensitive count value VSN of each column of pixel units. Preferably, the first photosensitive count value VSN can also be recorded through a memory.

Next, the RST signal controls each column of pixel units to reset for a second time, and each column of pixel units outputs a second reset voltage respectively. The ramp generating circuit generates a third ramp signal, and the counter starts counting from zero again. As the third ramp signal gradually increases, the voltage difference between the third ramp signal and the second reset voltage gradually shrinks. When the third ramp signal exceeds the second reset voltage, the comparator is triggered to turn over, and the count value of the counter at this time is the second reset count value VRZ of each column of pixel units. Preferably, the second reset count value VRZ can also be recorded through a memory.

After that, the TX signal controls the second exposure of each column of pixel units, and the second exposure time T2 is shorter than the normal exposure time (that is, the second exposure is a "short exposure" whose exposure time is shorter than the normal exposure time), and the pixels in each column are exposed for a second time. The units respectively output the second photosensitive voltage. Preferably, the second exposure time T2 can be adjusted by adjusting the input offset voltage of the comparator. The ramp generating circuit generates the fourth ramp signal, and the counter restarts to count from zero. As the fourth ramp signal gradually increases, the voltage difference between the fourth ramp signal and the second photosensitive voltage gradually decreases, and when the fourth ramp signal exceeds the second photosensitive voltage, triggering the The comparator is turned over, and at this time, the count value of the counter is the second photosensitive count value VSZ of each column of pixel units. Preferably, the second photosensitive count value VSZ can also be recorded through a memory.

Finally, the difference between the first exposure count value VSN and the first reset count value VRN of each column of pixel units is calculated to obtain the first exposure count difference value VSN-VRN; the second exposure count value VSZ of each column of pixel units is respectively calculated Calculate the difference with the second reset count value VRZ to obtain the second exposure count difference VSZ-VRZ; respectively calculate the first exposure count difference VSN-VRN and the second exposure count difference VSZ-VRZ of each column of pixel units Calculate the difference to obtain the pixel sensitivity value (VSN-VRN)-(VSZ-VRZ) of each column of pixel units, so as to eliminate the fixed pattern noise introduced by the pixel unit readout circuit and timing, and improve the image quality.

Compared with the first embodiment, the method of the second embodiment eliminates the fixed pattern noise introduced by the readout circuit more cleanly and thoroughly by adding the difference between the photosensitive count value and the reset count value of each of the two exposures, which is beneficial to the improvement of image quality. Further improve.

Those skilled in the art can understand that in this embodiment, the first ramp signal, the second ramp signal, the third ramp signal, and the fourth ramp signal are all upward ramp signals (the slope is positive). In the embodiment, these ramp signals may also be downward ramp signals (the slope is negative), and the illustration is only a schematic diagram.

In addition, theoretically speaking, the method of the present invention can also repeat the steps of short exposure multiple times to obtain a plurality of photosensitive count values whose exposure time of each column of pixel units is less than the normal exposure time, respectively. The difference between the photosensitive count value and a plurality of photosensitive count values whose exposure time is less than the normal exposure time is obtained to obtain the pixel photosensitive value of each column of pixel units, thereby eliminating the fixed pattern noise introduced by the timing more cleanly and thoroughly. However, in practical applications, it is usually necessary to comprehensively consider the application frame rate, conversion efficiency and other requirements to reasonably select the number of short exposures. Embodiments 1 and 2 only take a short exposure as an example rather than a limitation.

The pixel photosensitive value output method of the present invention adds a short exposure with an exposure time shorter than the normal exposure time in addition to the normal exposure, and effectively eliminates the pixel unit readout through the differential output of the normal exposure and short exposure of each column of pixel units. The fixed pattern noise introduced by the output circuit and timing further improves the image quality.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can use the methods and technical contents disclosed above to improve the present invention without departing from the spirit and scope of the present invention. The technical solutions are subject to possible changes and modifications. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solutions of the present invention belong to the technical solutions of the present invention. protected range.

Claims (7)

1. an output method of pixel sensitivity value, is characterized in that, comprises the following steps: A. After the first reset, each column of pixel units in the pixel array is exposed for the first time, and the first exposure time is the normal exposure time, and the first photosensitive voltage of each column of pixel units is output; The ramp signal is generated by the ramp generation circuit, the counter starts to count from zero, and the comparator compares the ramp signal with the first photosensitive voltage. As the ramp signal gradually increases, the voltage difference between the ramp signal and the first photosensitive voltage gradually decreases. When When the ramp signal exceeds the first photosensitive voltage, the comparator is triggered to flip, and the count value of the counter at this time is the first photosensitive count value of each column of pixel units; B. After the second reset, each column of pixel units in the pixel array is exposed for the second time, and the second exposure time is less than the normal exposure time, and the second photosensitive voltage of each column of pixel units is output; The ramp signal is generated by the ramp generating circuit, the counter starts to count from zero again, the comparator compares the ramp signal and the second photosensitive voltage, as the ramp signal gradually increases, the voltage difference between the ramp signal and the second photosensitive voltage gradually decreases, When the ramp signal exceeds the second photosensitive voltage, the trigger comparator is flipped, and the count value of the counter at this time is the second photosensitive count value of each column of pixel units; C. Calculate the difference between the first light-sensing count value and the second light-sensing count value of each column of pixel units, respectively, to obtain the pixel light-sensing value of each column of pixel units. 2. The output method of pixel photosensitive value as claimed in claim 1, characterized in that, comprising the following steps: A1. After the first reset, each column of pixel units in the pixel array is exposed for the first time, and the first exposure time is the normal exposure time, and the first photosensitive voltage of each column of pixel units is output; The ramp generating circuit generates the first ramp signal, and the counter starts to count from zero; The comparator compares the first ramp signal voltage with the first photosensitive voltage of each column of pixel units, and when the first ramp signal voltage exceeds the first photosensitive voltage of each column of pixel units, the counter obtains the first photosensitive voltage of each column of pixel units Photosensitive count value VSN; B1. After the second reset, each column of pixel units in the pixel array is exposed for the second time, and the second exposure time is less than the normal exposure time, and the second photosensitive voltage of each column of pixel units is output; The ramp generating circuit generates a second ramp signal, and the counter restarts to count from zero; The comparator compares the second ramp signal voltage with the second photosensitive voltage of each column of pixel units, and when the second ramp signal voltage exceeds the second photosensitive voltage of each column of pixel units, the counter obtains the second photosensitive voltage of each column of pixel units Photosensitive count value VSZ; C1. Calculate the difference between the first photosensitive count value VSN and the second photosensitive count value VSZ of each column of pixel units, respectively, to obtain the pixel photosensitive value VSN-VSZ of each column of pixel units. 3. The output method of pixel sensitivity value as claimed in claim 1, is characterized in that, comprises the following steps: A2. The first reset, generating the first reset voltage of each column of pixel units; The ramp generating circuit generates the first ramp signal, and the counter starts to count from zero; The comparator compares the first ramp signal voltage with the first reset voltage of each column of pixel units, and when the first ramp signal voltage exceeds the first reset voltage of each column of pixel units, the counter obtains the first reset voltage of each column of pixel units reset count value VRN; Each column of pixel units is exposed for the first time, and the first exposure time is a normal exposure time, and the first photosensitive voltage of each column of pixel units is output; The ramp generating circuit generates a second ramp signal, and the counter restarts to count from zero; The comparator compares the second ramp signal voltage with the first photosensitive voltage of each column of pixel units, and when the second ramp signal voltage exceeds the first photosensitive voltage of each column of pixel units, the counter obtains the first photosensitive voltage of each column of pixel units Photosensitive count value VSN; B2. The second reset, the second reset voltage of each column of pixel units is generated; The ramp generating circuit generates a third ramp signal, and the counter restarts to count from zero; The comparator compares the third ramp signal voltage with the second reset voltage of each column of pixel units, and when the third ramp signal voltage exceeds the second reset voltage of each column of pixel units, the counter obtains the second reset voltage of each column of pixel units reset count value VRZ; Each column of pixel units is exposed for the second time, and the second exposure time is shorter than the normal exposure time, and the second photosensitive voltage of each column of pixel units is output; The ramp generating circuit generates the fourth ramp signal, and the counter restarts to count from zero; The comparator compares the fourth ramp signal voltage with the second photosensitive voltage of each column of pixel units, and when the fourth ramp signal voltage exceeds the second photosensitive voltage of each column of pixel units, the counter obtains the second photosensitive voltage of each column of pixel units Photosensitive count value VSZ; C2. Calculate the difference between the first photosensitive count value VSN and the first reset count value VRN of each column of pixel units to obtain the first exposure count difference value VSN-VRN; Calculate the difference between the second photosensitive count value VSZ and the second reset count value VRZ of each column of pixel units, to obtain the second exposure count difference value VSZ-VRZ; Calculate the difference between the first exposure count difference VSN-VRN and the second exposure count difference VSZ-VRZ of each column of pixel units to obtain the pixel sensitivity value of each column of pixel units (VSN-VRN)-(VSZ-VRZ ). 4 . The method for outputting the pixel photosensitive value according to claim 1 , wherein the step B is repeated to obtain a plurality of photosensitive count values whose exposure time of each column of pixel units is less than the normal exposure time, respectively, for each column of pixels. 5 . The first light-sensing count value of the unit and a plurality of light-sensing count values whose exposure time is less than the normal exposure time are calculated to obtain the pixel light-sensing value of each column of pixel units. 5 . The method for outputting the photosensitive value of a pixel according to claim 1 , wherein the second exposure time is adjusted according to the input offset voltage of different comparators. 6 . 6 . The method for outputting a pixel photosensitive value according to claim 2 , wherein the first ramp signal, the second ramp signal, the third ramp signal, and the fourth ramp signal are upward ramp signals or upward ramp signals. 7 . down the ramp signal. 7. The method for outputting a pixel sensitivity value according to claim 2 or 3, further comprising: The first reset count value, the second reset count value, the first photosensitive count value, and the second photosensitive count value are recorded through the memory.

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