Digital image processor for a digital camera

• US 7,903,149 B2
• Filed: 10/31/2007
• Issued: 03/08/2011
• Est. Priority Date: 05/29/1998
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies Fiber IP Singapore PTE Limited (Broadcom, Inc.)
• Inventors: Safai, Mohammad A.
• Primary Examiner(s): VU, NGOC YEN T
• Application Number:
  US11/932,478
• Publication Number:
  US 20080055428A1
• Time in Patent Office: 1,224 Days
• Field of Search: 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 image process for a digital camera contains a preprocessor and a postprocessor. The preprocessor can include, for example, a uniformity corrector, a sampling filter, a modulation transformer, and a ditherer. The postprocessor can include a color interpolator, an RGB reconstruction block, a digital compressor, and a color pattern data buffer. The digital image process is programmable to operate one or more of the processing blocks of one or both the preprocessor and the postprocessor for flexible programming that can adapt to the requirements of various digital camera designs or users.

Claims

1. A digital image processor for use in a digital camera having an imaging device arranged to output digital images and a memory for storing digital images, the digital image processor comprising:

a preprocessor comprising hardware for preprocessing digital images received from the imaging device and storing the digital images in the memory;

a postprocessor comprising hardware arranged to receive digital images and to postprocess the digital images into a viewable form;

wherein the digital image processor is operable in a first mode in which data corresponding to preprocessed images from the preprocessor are directed to the memory, thereby bypassing the postprocessor;

wherein the digital image processor is operable in a second mode in which data corresponding to the preprocessed images from the preprocessor are directed to the postprocessor for postprocessing and data corresponding to postprocessed images from the postprocessor are directed to the memory; and

a system bus within the digital image processor, wherein the preprocessor, the postprocessor, and an interface for the memory are coupled to the system bus.

2. A digital image processor as recited in claim 1, wherein the postprocessor includes a color interpolator arranged to derive an unknown pixel color value associated with a first pixel based upon at least one known pixel color value associated with at least one other pixel using pixel color weight factors associated with an image sensor in the imaging device.

3. A digital image processor as recited in claim 2, further including a color pattern setting buffer that is connected to the color interpolator and capable of storing image sensor data associated with the image sensor included in the imaging device, the image sensor data being used to derive the associated pixel color weight factors.

4. A digital image processor as recited in claim 1, wherein the postprocessor is arranged such that its operation does not interfere with the operation of the preprocessor or taking pictures using the digital camera.

5. A digital camera comprising:

an imaging device arranged to output digital images;

a digital image processor as recited in claim 1; and

memory for storing the digital images.

6. A digital image processor for use in a digital camera having an imaging device arranged to output digital images and a memory for storing digital images, the digital image processor comprising:

a preprocessor comprising hardware for preprocessing digital images received from the imaging device and storing the digital images in the memory;

a postprocessor comprising hardware arranged to receive digital images and to postprocess the digital images into a viewable form;

wherein the digital image processor is operable in a first mode in which data corresponding to preprocessed images from the preprocessor are directed to the memory, thereby bypassing the postprocessor;

wherein the digital image processor is operable in a second mode in which data corresponding to the preprocessed images from the preprocessor are directed to the postprocessor for postprocessing and data corresponding to postprocessed images from the postprocessor are directed to the memory; and

wherein the postprocessor includes a color interpolator arranged to derive an unknown pixel color value associated with a first pixel based upon at least one known pixel color value associated with at least one other pixel using pixel color weight factors associated with an image sensor in the imaging device.

7. A digital image processor as recited in claim 6, further including a color pattern setting buffer that is connected to the color interpolator and capable of storing image sensor data associated with the image sensor included in the imaging device, the image sensor data being used to derive the associated pixel color weight factors.

8. A digital image processor as recited in claim 6, wherein the postprocessor is arranged such that its operation does not interfere with the operation of the preprocessor or taking pictures using the digital camera.

9. A digital camera comprising:

an imaging device arranged to output digital images;

a digital image processor as recited in claim 6; and

memory for storing the digital images.

10. A digital image processor for use in a digital camera having an imaging device arranged to output digital images and a memory for storing digital images, the digital image processor comprising:

a preprocessor comprising hardware for preprocessing digital images received from the imaging device and storing the digital images in the memory;

a postprocessor comprising hardware arranged to receive digital images and to postprocess the digital images into a viewable form;

wherein the digital image processor is operable in a first mode in which data corresponding to preprocessed images from the preprocessor are directed to the memory, thereby bypassing the postprocessor;

wherein the digital image processor is operable in a second mode in which data corresponding to the preprocessed images from the preprocessor are directed to the postprocessor for postprocessing and data corresponding to postprocessed images from the postprocessor are directed to the memory;

wherein the postprocessor is arranged such that its operation does not interfere with the operation of the preprocessor or taking pictures using the digital camera; and

wherein the postprocessor includes a color interpolator arranged to derive an unknown pixel color value associated with a first pixel based upon at least one known pixel color value associated with at least one other pixel using pixel color weight factors associated with an image sensor in the imaging device.

11. A digital image processor as recited in claim 10, further including a color pattern setting buffer that is connected to the color interpolator and capable of storing image sensor data associated with the image sensor included in the imaging device, the image sensor data being used to derive the associated pixel color weight factors.

12. A digital camera comprising:

an imaging device arranged to output digital images;

a digital image processor as recited in claim 10; and

memory for storing the digital images.