Systems and methods for performing depth estimation using image data from multiple spectral channels

A method of synthesizing a higher resolution image from a light field comprising a set of lower resolution images captured from different viewpoints and within multiple color channels, the method comprising:

• estimating distances to objects within a scene from the light field comprising a set of images captured from different viewpoints and within multiple color channels using a processor configured by an image processing application, the method comprising:
• selecting a reference viewpoint relative to the viewpoints of the set of images captured from different viewpoints and within multiple color channels;
• normalizing the set of images to increase the similarity of pixels from the set of images that correspond in a specific color channel from the multiple color channels;
• determining depth estimates for pixel locations in an image from the reference viewpoint using at least a subset of the set of images, where a depth estimate for a given pixel location in the image from the reference viewpoint is determined by:
• identifying pixels in the at least a subset of the set of images that correspond to the given pixel location in the image from the reference viewpoint based upon expected disparity at a plurality of depths;
• in each of a plurality of color channels selected from the multiple color channels, comparing the similarity of the pixels that are identified as corresponding in the selected color channel at each of the plurality of depths;
• and
• selecting the depth from the plurality of depths at which the identified corresponding pixels in each of the plurality of color channels have the highest degree of similarity as a depth estimate for the given pixel location in the image from the reference viewpoint
• determining the visibility of the pixels in the set of images from the reference viewpoint by:
• identifying corresponding pixels in the set of images using the depth estimates;
• and
• determining that a pixel in a given image is not visible in the reference viewpoint when the pixel fails a photometric similarity criterion determined based upon a comparison of corresponding pixels within the color channel to which the pixel belongs;
• and
• fusing pixels from the set of images using the processor configured by the image processing application based upon the depth estimates to create a fused image having a resolution that is greater than the resolutions of the images in the set of images by:
• identifying the pixels from the set of images that are visible in an image from the reference viewpoint using the visibility information;
• applying scene dependent geometric shifts to the pixels from the set of images that are visible in an image from the reference viewpoint to shift the pixels into the reference viewpoint, where the scene dependent geometric shifts are determined using the current depth estimates;
• and
• fusing the shifted pixels from the set of images to create a fused image from the reference viewpoint having a resolution that is greater than the resolutions of the images in the set of images.

An image processing system, comprising:

• a processor;
• memory containing a set of images captured from different viewpoints and within multiple color channels and an image processing application;
• wherein the image processing application configures the processor to:
• select a reference viewpoint relative to the viewpoints of the set of images captured from different viewpoints and within multiple color channels;
• normalize the set of images to increase the similarity of corresponding pixels within the set of images that correspond in a specific color channel from the multiple color channels;
• determine depth estimates for pixel locations in an image from the reference viewpoint using at least a subset of the set of images, where a depth estimate for a given pixel location in the image from the reference viewpoint is determined by:
• identifying pixels in the at least a subset of the set of images that correspond to the given pixel location in the image from the reference viewpoint based upon expected disparity at a plurality of depths;
• in each of a plurality of color channels selected from the multiple color channels, comparing the similarity of the pixels that are identified as corresponding in the selected color channel at each of the plurality of depths;
• and
• selecting the depth from the plurality of depths at which the identified corresponding pixels in each of the plurality of color channels have the highest degree of similarity as a depth estimate for the given pixel location in the image from the reference viewpoint.