Stabilization of three-dimensional images in a scannerless range imaging system

A method for generating a stabilized three-dimensional image from a scannerless range imaging system of the type comprising an illuminator for illuminating a scene with modulated illumination;

• an image modulating component for receiving and modulating the modulated illumination reflected from the scene;
• an image capture element for capturing images output by the image modulating component, including a bundle of at least three phase offset images each incorporating a phase delay corresponding to the distance of objects in the scene from the illuminator, wherein each phase offset image also incorporates a phase offset unique for each image, said method comprising the steps of:
• acquiring a bundle of three or more phase offset images corresponding to the reflected modulated illumination, whereby one or more of the phase offset images may be subject to movement with respect to another phase offset image;
• choosing a motion model for estimating movement between the images;
• searching for a stable chain of phase offset images in the image bundle, where a stable chain is a collection of images that is found to exist where the motion model reveals a correlation between the images indicative of correctable global motion;
• correcting for the global motion in the stable chain of images if a stable chain of at least three phase offset images is found to exist;
• and
• computing a stabilized three-dimensional image using corrected phase offset images from the stable chain of phase offset images.

In a method for generating a three-dimensional image from a scannerless range imaging system of the type that computes range information from at least three images each incorporating a phase delay corresponding to the distance of objects in the scene from the range imaging system, the improvement wherein the method comprises the steps of:

• acquiring a bundle of three or more images, whereby one or more of the images may be subject to unwanted movement with respect to another image;
• searching for a stable chain of at least three images in the image bundle, where a stable chain is a collection of images that is found to exist where it is possible to characterize the unwanted movement between the images in relation to a motion model that is sensitive to a predetermined type of motion between the images;
• if a stable chain of at least three phase offset images does not exist, requiring an image bundle until a stable chain is found to exist;
• correcting for unwanted motion in the stable chain of images;
• and
• computing a stabilized three-dimensional image using the images from the stable chain of phase offset images.

A scannerless range imaging system for generating a stabilized three-dimensional image, said system comprising:

• an illuminator for illuminating a scene with modulated illumination;
• an image modulating component for receiving and modulating the modulated illumination reflected from the scene;
• an image capture element for capturing images output by the image modulating component, whereby one or more of the images also includes image motion relative to another image, said captured images including a bundle of at least three phase offset images each incorporating a phase delay corresponding to the distance of objects in the scene from the illuminator, wherein each phase offset image also incorporates a phase offset unique for each image,;
• and
• a processor for processing the phase offset images captured by the image capture device, said processor performing the steps of:
• searching for a stable chain of phase offset images in the image bundle, wherein a stable chain is a collection of images that is obtained by testing the phase offset images against a confidence measure that separates less severe correctable image motion from more severe image motion and then populating the stable chain only with those phase offset images that meet the confidence measure for correctable image motion;
• correcting for the image motion in the stable chain of images if a stable chain of at least three phase offset images is found to exist;
• and
• computing a stabilized three-dimensional image using the phase offset images from the stable chain of phase offset images