Dynamic range extending method and apparatus using subsampling

• US 8,390,690 B2
• Filed: 05/07/2009
• Issued: 03/05/2013
• Est. Priority Date: 07/08/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lim, Yong
• Primary Examiner(s): Henn, Timothy J
• Application Number:
  US12/453,335
• Publication Number:
  US 20100007778A1
• Time in Patent Office: 1,398 Days
• Field of Search: 348/294, 348/296, 348/297, 348/302, 348/308, 348/216.1
• US Class Current: 348/216.1
• CPC Class Codes: H04N 23/70 Circuitry for compensating brightness variation in the scene
• CPC Class Codes: H04N 23/741 by increasing the dynamic range of the image compared to the dynamic range of the electronic image sensors

Abstract

A method and apparatus subsampling a plurality of signals from one frame of a pixel array, pixels within the pixel array belonging to one of at least two sets, each set configured to sense values of a same image parameter, includes controlling integration times for first and second signals for each set output from the pixel array, controlling including using a first integration time for the first signal of the set and using a second integration time, different than the first integration time, for the second signal of the set, and calculating a synthesized value for each set using the first and second signals having different integration times.

Claims

1. A method of subsampling a plurality of signals from one frame of a pixel array within one frame, pixels within the pixel array belonging to one of at least two sets, each set being configured to sense value of a same image parameter, the method comprising:

controlling integration times for first and second signals for each set output from the pixel array, controlling including using a first integration time for the first signal of the set and using a second integration time, different than the first integration time, for the second signal of the set; and

generating a synthesized value from the first and second signals for each set output from the pixel array, the generating including calculating a sub-sampled value for each set using the first and second signals having different integration times for each set.

2. An imaging apparatus, comprising:

an array of pixels configured to output a plurality of signals within one frame, pixels within the pixel array belonging one of at least two sets, each set being configured to sense value of a same image parameter; and

a controller configured to generate a synthesized value from first and second signals for each set output from the pixel array, generation of the synthesized value includes using a first integration time for the first signal, using a second integration time, different than the first integration time, for the second signal, and calculating a sub-sampled value for each set from the first and second signals having different integration times for each set.

3. The imaging apparatus as claimed in claim 2, wherein each pixel includes a plurality of subpixels.

4. The imaging apparatus as claimed in claim 3, wherein at least two sub-pixels within a single pixel have different integration times.

5. The imaging apparatus as claimed in claim 3, wherein the controller is configured to control whether sub-pixels within each pixel have a same or different integration times in accordance with a dynamic range of an image incident on the pixel array.

6. The imaging apparatus as claimed in claim 3, wherein the first signal of the first set is output from a first sub-pixel and the second signal of the first set is output from a second sub-pixel.

7. The imaging apparatus as claimed in claim 6, wherein the first and second signal sub-pixels are within a same pixel.

8. The imaging apparatus as claimed in claim 2, wherein the first signal is output from a first pixel and the second signal is output from a second pixel.

9. The imaging apparatus as claimed in claim 2, wherein the controller is configured to select an integration time for each individual pixel.

10. The imaging apparatus as claimed in claim 2, wherein the controller is configured to select an integration time for each row in the pixel array.

11. The imaging apparatus as claimed in claim 2, wherein the controller is configured to select an integration time for each column in the pixel array.

12. The imaging apparatus as claimed in claim 3, wherein the image parameter is color.

13. The imaging apparatus as claimed in claim 2, wherein signals within each set are output from nearest portions of the pixel array.

14. The imaging apparatus as claimed in claim 2, wherein the controller is configured to average the first and second signals.

15. The imaging apparatus as claimed in claim 14, wherein the controller is configured to generate a weighted average the first and second signals.

16. The imaging apparatus as claimed in claim 2, wherein the controller is configured to use a third integration time for a third signal for each set, the third integration time being different than the first and second integration times.

17. The imaging apparatus as claimed in claim 2, wherein the controller is configured to control a ratio of signals sampled using the first integration time to signals sampled using the second integration time.

18. The imaging apparatus as claimed in claim 17, wherein the controller is configured to control the ratio is in accordance with a dynamic range of an image incident on the pixel array.

19. The imaging apparatus as claimed in claim 2, wherein the controller is configured to alter at least one of the first and second integration times in accordance with a dynamic range of an image incident on the pixel array.

20. The imaging apparatus as claimed in claim 2, wherein the first set is a first color and the second set is a second color different from the first color.

21. A system, comprising:

a processor;

a memory device in communication with the processor; and

an image sensor in communication with at least one of the processor and the memory device, the image sensor including,

a pixel array configured to output a plurality of signals within one frame, pixels within the pixel array belonging one of at least two sets, each set being configured to sense values of a same image parameter;

a controller configured to generate synthesized value from first and second signals for each set output from the pixel array, generation of the synthesized value includes using a first integration time for the first signal, using a second integration time, different than the first integration time, for the second signal, and calculating a sub-sampled value for each set from the first and second signals having different integration times for each set; and

an analog to digital converter configured to receive synthesized value from the controller and to output a corresponding digital signal to the one of the processor and memory device.