Digital image processor for a digital camera

• US 9,025,045 B2
• Filed: 05/21/2013
• Issued: 05/05/2015
• Est. Priority Date: 05/29/1998
• Status: Expired due to Fees

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Safai, Mohammad A.
• Primary Examiner(s): VU, NGOC YEN T
• Application Number:
  US13/899,274
• Publication Number:
  US 20130250138A1
• Time in Patent Office: 714 Days
• Field of Search: 348/207.99, 348/222.1
• US Class Current: 348/222.1
• CPC Class Codes: H04N 2209/046 Colour interpolation to calculate the missing colour values
• CPC Class Codes: H04N 23/617 Upgrading or updating of programs or applications for camera control
• CPC Class Codes: H04N 23/631 Graphical user interfaces [GUI] specially adapted for controlling image capture or setting capture parameters
• CPC Class Codes: H04N 23/843 Demosaicing, e.g. interpolating colour pixel values
• CPC Class Codes: H04N 23/88 for colour balance, e.g. white-balance circuits or colour temperature control
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof
• CPC Class Codes: H04N 25/134 based on three different wavelength filter elements
• CPC Class Codes: H04N 25/67 applied to fixed-pattern noise, e.g. non-uniformity of response
• CPC Class Codes: H04N 25/745 Circuitry for generating timing or clock signals
• CPC Class Codes: H04N 5/765 Interface circuits between an apparatus for recording and another apparatus
• CPC Class Codes: H04N 5/772 the recording apparatus and the television camera being placed in the same enclosure
• CPC Class Codes: H04N 5/775 between a recording apparatus and a television receiver
• CPC Class Codes: H04N 5/907 using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence
• CPC Class Codes: H04N 9/8047 using transform coding

Abstract

A digital camera and methods of operating a digital camera are disclosed. In one aspect of the invention, a digital camera includes an imaging unit including an image sensor and imaging optics and a digital image processor connected to receive raw digital images from the imaging unit and to process the raw digital images. The digital camera also includes a memory configured to store digital image data that has been pre-processed by the digital image processor and a processor configured to direct retrieval of the digital image data that is stored in the memory and the digital image processor comprises a pre-processing portion and a post-processing portion, the pre-processing portion including a uniformity corrector configured to correct non-uniformities using Photo Response Non-Uniformity (PRNU) correction and/or white balancing.

Claims

1. A digital camera, the digital camera comprising:

an imaging unit including an image sensor and imaging optics;

a digital image processor connected to receive raw digital images from the imaging unit and to process the raw digital images;

a memory configured to store digital image data that has been pre-processed by the digital image processor;

a microprocessor configured to direct retrieval of the digital image data that is stored in the memory; and

a display for viewing digital images;

wherein the digital image processor comprises a pre-processing portion and a post-processing portion, the pre-processing portion including a uniformity corrector configured to correct non-uniformities in the raw digital images using Photo Response Non-Uniformity (PRNU) correction and including a sampling filter, which receives corrected raw digital images from the uniformity corrector, and is configured to reduce the amount of data in the raw digital images for immediate viewing on the display before post-processing operations including color interpolation, RGB reconstruction, and compression.

2. The digital camera of claim 1, wherein the uniformity corrector is located to receive the raw image data before other functional units in the pre-processor.

3. The digital camera of claim 1, wherein the uniformity corrector is further configured to correct uniformities using white balancing.

4. The digital camera of claim 1, wherein the sampling filter is programmable so that the amount of data reduction may be set by a manufacturer or programmed by the microprocessor.

5. A method of operating a digital camera, the method comprising:

capturing raw image data using an imaging unit that includes an image sensor and imaging optics;

pre-processing the raw image data in a digital image processor connected to receive raw digital images from the imaging unit to correct non-uniformities in the raw image data, wherein the pre-processing comprises Photo Response Non-Uniformity (PRNU) correction and wherein the pre-processing further comprises sampling the corrected raw image data to reduce the amount of data in the raw image data; and

immediately displaying the sampled raw image data on a display of the digital camera without first subjecting the pre-processed raw digital data to post-processing operations including color interpolation, RGB reconstruction, and compression.

6. The method of claim 5 further comprising storing the corrected raw image data in a memory of the digital camera.

7. The method of claim 5 further comprising storing the corrected raw image data in a memory of the digital camera directly after the pre-processing.

8. The method of claim 5 wherein the raw image data is pre-processed to correct non-uniformities before being stored in a memory of the digital camera or displayed on a display device of the digital camera.

9. The method of claim 5 wherein the pre-processing comprises white balancing.

10. The method of claim 5, further comprising programming a sampling filter of the digital image processor to change the amount of data reduction.

11. A digital camera, the digital camera comprising:

an imaging unit including an image sensor and imaging optics;

a digital image processor connected to receive raw digital images from the imaging unit and to process the raw digital images;

a memory configured to store digital image data that has been pre-processed by the digital image processor;

a microprocessor configured to direct retrieval of the digital image data that is stored in the memory; and

a display for viewing digital images;

wherein the digital image processor comprises a pre-processing portion and a post-processing portion, the pre-processing portion including a uniformity corrector configured to correct non-uniformities in the raw digital images using white balancing and including a sampling filter, which receives corrected raw digital images from the uniformity corrector, and is configured to reduce the amount of data in the raw digital images for at least one of immediate display on the display and storage in the memory before post-processing operations including color interpolation, RGB reconstruction, and compression.

12. The digital camera of claim 11, wherein the uniformity corrector is located to receive the raw image data before other functional units in the pre-processor.

13. The digital camera of claim 11, wherein the uniformity corrector is further configured to correct uniformities using Photo Response Non-Uniformity (PRNU) correction.

14. The digital camera of claim 11, wherein the sampling filter is programmable so that the amount of data reduction may be set by a manufacturer or programmed by the microprocessor.

15. A method of operating a digital camera, the method comprising:

capturing raw image data using an imaging unit that includes an image sensor and imaging optics;

pre-processing the raw image data in a digital image processor connected to receive raw digital images from the imaging unit to correct non-uniformities in the raw image data, wherein the pre-processing comprises white balancing and wherein the pre-processing further comprises sampling the corrected raw image data to reduce the amount of data in the raw digital images; and

at least one of immediately displaying the sampled raw digital images on a display of the digital camera and storing the sampled raw digital images in the memory without first subjecting the pre-processed raw digital data to post-processing operations including color interpolation, RGB reconstruction, and compression.

16. The method of claim 15 further comprising storing the corrected raw image data in a memory of the digital camera.

17. The method of claim 15 further comprising storing the corrected raw image data in a memory of the digital camera directly after the pre-processing.

18. The method of claim 15 wherein the raw image data is pre-processed to correct non-uniformities before being stored in a memory of the digital camera or displayed on a display device of the digital camera.

19. The method of claim 15 wherein the pre-processing comprises Photo Response Non-Uniformity (PRNU) correction.

20. The method of claim 15, further comprising programming a sampling filter of the digital image processor to change the amount of data reduction.