Non Uniform Blending of Exposure and/or Focus Bracketed Photographic Images

• US 20060239579A1
• Filed: 04/22/2005
• Published: 10/26/2006
• Est. Priority Date: 04/22/2005
• Status: Abandoned Application

• Current Assignee: Bradford Allison Ritter
• Original Assignee: Bradford Allison Ritter
• Inventors: Ritter, Bradford Allison
• Application Number:
  US10/907,993
• Publication Number:
  US 20060239579A1
• Time in Patent Office: Days
• US Class Current: 382/274
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction

Abstract

The present invention provides a method for the non-uniform blending of digital representations of photographic images. The method of the present invention is a computer program. In accordance with the method of the present invention, a pair of exposure or focus bracketed photographic images are blended together to produce a single image with the best characteristics of the original images. A pixel characteristic is chosen to control the blending of the two images. Each pixel in the pair of images is analyzed, producing a single scalar value for each pixel that represents the chosen characteristic. For each image the scalar values can optionally be smoothed. Smoothing consists of averaging the scalar values for a pixel with the scalar value for all pixels within a specified neighboring region. The scalar values for all pairs of pixels are then analyzed to calculate the maximum of (scalar1_value-scalar2_value) and the minimum of (scalar1_value-scalar2_value). The values scalar1_value and scalar2_value correspond to the calculated scalar values for a pixel pair according to the chosen pixel characteristic. The pixel intensities for each pair of pixels is optionally adjusted to a common value. The common intensity value for a pair of pixels is a function of the original intensities of the pixel pair. Finally, each pixel pair is blended according to an arbitrary blending function. The blending function is a function of the independent variables: (scalar1_value-scalar2_value) for the pixel pair to be blended; max(scalar1_value-scalar2_value) for all pixel pairs in the images to be blended; min(scalar1_value-scalar2_value) for all pixel pairs in the images to be blended.

Claims

1. A method for blending digital representations of two photographic images in proportions that vary from one pixel to another:

logic that associates a scalar value with each pixel of each image; and

logic that blends corresponding pixels as a function of the associated scalar values.

2. The method of claim 1, further comprising two images that are similar while varying in the exposure settings used at the time the photographs are acquired.

3. The method of claim 1, further comprising two images that are similar while varying in the focus distance used at the time the photographs are acquired.

4. The method of claim 1, further comprising scalar values associated with each pixel of each image that is a scalar representation of the pixel'"'"'s color saturation.

5. The method of claim 1, further comprising scalar values associated with each pixel of each image that is a scalar representation of the pixel'"'"'s hue.

6. The method of claim 1, further comprising scalar values associated with each pixel of each image that is a scalar representation of the pixel'"'"'s contrast, where contrast is a measure of a pixel'"'"'s intensity relative to neighboring pixels.

7. The method of claim 1, further comprising a blending function that is an arbitrary function of:

(image1_scalar-image2_scalar) for each pair of pixels to be blended;

the maximum of (image1−

scalar-image2_scalar) for all pairs of pixels in the two images;

the minimum of (image1−

scalar-image2_scalar) for all pairs of pixels in the two images.

8. The method of claim 1, further comprising a smoothing pass on the scalar values associated with each pixel in each image prior to the blending operation;

smoothing is the averaging of all pixel scalar values within a specified neighboring region.

9. The method of claim 1, further comprising the modification of the intensity of pairs of pixels to be blended, where the adjusted intensity is a function of the intensity of the two pixels to be blended.

10. A system comprising a system capable of blending the digital representations of two photographic images.

11. The system of claim 10, further embodied as a computer software program.

12. The system of claim 10, further comprising any digital processing device capable of effecting the instructions of said software program.