Zoomed histogram display for a digital camera

• US 7,130,463 B1
• Filed: 12/04/2002
• Issued: 10/31/2006
• Est. Priority Date: 12/04/2002
• Status: Active Grant

• Current Assignee: Foveon, Inc. (Avis Budget Group Incorporated)
• Original Assignee: Foveon, Inc. (Avis Budget Group Incorporated)
• Inventors: Spangler, Randall R.
• Primary Examiner(s): Do, Anh Hong
• Application Number:
  US10/310,601
• Time in Patent Office: 1,427 Days
• Field of Search: 382/128, 382/134, 382/274, 382/118, 382/164, 382/165, 348/65, 348/74, 348/620, 348/337, 348/374, 600/109, 600/118, 600/129
• US Class Current: 382/168
• CPC Class Codes: G06T 2200/24 involving graphical user interfaces [GUIs]
• CPC Class Codes: G06T 2207/10024 Color image
• CPC Class Codes: G06T 2207/20104 Interactive definition of region of interest [ROI]
• CPC Class Codes: G06T 7/90 Determination of colour characteristics
• CPC Class Codes: G06V 10/50 by performing operations within image blocks; by using histograms, e.g. histogram of oriented gradients [HoG]; by summing image-intensity values; Projection analysis
• CPC Class Codes: H04N 2101/00 Still video cameras
• CPC Class Codes: H04N 23/635 Region indicators; Field of view indicators
• CPC Class Codes: H04N 23/695 Control of camera direction for changing a field of view, e.g. pan, tilt or based on tracking of objects

Abstract

An apparatus and a method are provided to allow a portion of a captured image to be evaluated with a digital camera. A display device of the digital camera can display the captured image. A specific area of interest of the captured image can be defined on the display device by zooming and panning or by defining a window over the captured image, and a histogram derived from only that area of interest can be displayed. The histogram can represent different types of information about the pixels of the captured image within the area of interest such as the levels of individual colors and luminance.

Claims

1. A method for providing a zoomed histogram display on a digital camera, comprising:

reading a captured image from a memory device and displaying it as a digital image on a display device of the digital camera including mapping a first number of stored pixels of the captured image to displayed pixels of the display device;

zooming the digital image until only an area of interest of the digital image is displayed;

deriving a histogram based on the area of interest; and

displaying the histogram.

2. The method of claim 1 wherein zooming the digital image includes mapping a second number of stored pixels of the captured image to the displayed pixels, the second number of stored pixels being less than the first number of stored pixels.

3. The method of claim 2 where each stored pixel of the second number of stored pixels includes a value within a range for an image value.

4. The method of claim 3 wherein deriving the histogram includes

dividing the range into a number of bins so that each bin represents a part of the range, and

counting for each bin the stored pixels of the second number of stored pixels that have values within the part of the range represented by that bin.

5. The method of claim 2 wherein the image value represents a level of a color channel.

6. The method of claim 2 wherein each stored pixel of the second number of stored pixels includes a value within a range for each of three color channels.

7. The method of claim 6 wherein deriving the histogram includes

dividing the range for each of the three color channels into a number of bins so that each bin represents a part of that range, and

counting for each bin of each color channel the stored pixels of the second number of stored pixels that have values within the part of the range represented by that bin.

8. The method of claim 6 wherein deriving the histogram includes

calculating for each stored pixel of the second number of stored pixels a weighted combination of the values of the three color channels to determine a derived value within a derived range,

dividing the derived range into a number of bins so that each bin represents a part of the derived range, and

counting for each bin the stored pixels of the second number of stored pixels that have derived values within the part of the derived range represented by that bin.

9. The method of claim 8 wherein the derived value is a luminance value.

10. A method for providing a zoomed histogram display on a display device, comprising:

reading a captured image from a memory device and displaying it as a digital image on the display device including mapping a first number of stored pixels of the captured image to displayed pixels of the display device;

zooming the digital image until only an area of interest of the digital image is displayed;

deriving a histogram based on the area of interest; and

displaying the histogram.

11. The method of claim 10 wherein zooming the digital image includes mapping a second number of stored pixels of the captured image to the displayed pixels, the second number of stored pixels being less than the first number of stored pixels.

12. The method of claim 10 where each stored pixel of the second number of stored pixels includes a value within a range for an image value.

13. The method of claim 12 wherein deriving the histogram includes

dividing the range into a number of bins so that each bin represents a part of the range, and

counting for each bin the stored pixels of the second number of stored pixels that have values within the part of the range represented by that bin.

14. The method of claim 10 wherein the image value represents a level of a color channel.

15. The method of claim 10 wherein each stored pixel of the second number of stored pixels includes a value within a range for each of three color channels.

16. The method of claim 15 wherein deriving the histogram includes

dividing the range for each of the three color channels into a number of bins so that each bin represents a part of that range, and

counting for each bin of each color channel the stored pixels of the second number of stored pixels that have values within the part of the range represented by that bin.

17. The method of claim 15 wherein deriving the histogram includes

calculating for each stored pixel of the second number of stored pixels a weighted combination of the values of the three color channels to determine a derived value within a derived range,

dividing the derived range into a number of bins so that each bin represents a part of the derived range, and

counting for each bin the stored pixels of the second number of stored pixels that have derived values within the part of the derived range represented by that bin.

18. The method of claim 17 wherein the derived value is a luminance value.