초록 ▼

A system and method for deghosting mosaics provides a novel multiperspective plane sweep approach for generating an image mosaic from a sequence of still images, video images, scanned photographic images, computer generated images, etc. This multiperspective plane sweep approach uses virtual camera

A system and method for deghosting mosaics provides a novel multiperspective plane sweep approach for generating an image mosaic from a sequence of still images, video images, scanned photographic images, computer generated images, etc. This multiperspective plane sweep approach uses virtual camera positions to compute depth maps for columns of overlapping pixels in adjacent images. Object distortions and ghosting caused by image parallax when generating the image mosaics are then minimized by blending pixel colors, or grey values, for each computed depth to create a common composite area for each of the overlapping images. Further, the multiperspective plane sweep approach described herein is both computationally efficient, and applicable to both the case of limited overlap between the images used for creating the image mosaics, and to the case of extensive or increased image overlap.

대표청구항 ▼

What is claimed is: 1. A system for blending pixels in overlapping images of a scene comprising using a computing device to perform the following steps: determining an area of overlap between at least two images having a common viewing plane; dividing the area of overlap into at least one column of

What is claimed is: 1. A system for blending pixels in overlapping images of a scene comprising using a computing device to perform the following steps: determining an area of overlap between at least two images having a common viewing plane; dividing the area of overlap into at least one column of image pixels, each column having a width of at least one pixel; computing a depth map for each column; identifying pixels from at least one image that correspond to the depth map; blending at least two identified pixels wherein a composite image pixel is produced by blending the at least two identified pixels; and assigning each composite pixel to the column used for identifying the pixels blended to produce the composite pixel. 2. The system of claim 1 wherein the composite pixel is assigned to a portion of each overlapping image represented by the column so that the composite pixel is common to each overlapping image. 3. The system of claim 1 wherein at least two overlapping images of a scene having different perspective viewing planes are warped to bring each image into the common viewing plane prior to determining the area of overlap between the at least two images. 4. The system of claim 1 wherein the depth map for each column is computed by using a plane sweep from a virtual origin perpendicular to each column. 5. The system of claim 1 wherein the depth map for each column is computed using pixel distances measured by a laser range finder at the time each image was acquired. 6. The system of claim 1 wherein the depth map for each column is computed using pixel distances measured by a radar range finder at the time each image was acquired. 7. The system of claim 1 further comprising aligning overlapping image areas prior to dividing the area of overlap into at least one column. 8. The system of claim 1 further comprising compensating for exposure variation between overlapping images by adjusting an exposure of at least one of the overlapping images so that the exposure is consistent between the overlapping images. 9. The system of claim 1 further comprising weighting each identified pixel prior to pixel blending. 10. The system of claim 1 wherein a linear weighting that is a function of a proximity to an edge of the area of overlap and to the point of origin for each image is applied to each identified pixel prior to pixel blending. 11. The system of claim 1 wherein pixel blending is achieved by averaging the pixels that are blended. 12. The system of claim 9 wherein pixel blending is achieved by averaging the weighted pixels that are blended. 13. The system of claim 3 further comprising warping each image back to its original perspective viewing plane after pixel blending. 14. The system of claim 1 wherein at least one of the overlapping images of a scene is acquired using at least one camera. 15. The system of claim 1 wherein at least two cameras having overlapping fields of view are used to acquire overlapping images of a scene. 16. A computer-implemented process for generating a common composite area for overlapping images comprising using a computer to: input two or more overlapping images; warp each overlapping image into a common viewing plane; align an overlapping region of the two images; divide the overlapping region into at least one column of image pixels, each column having a width of at least one pixel; compute a depth map for each column; identify pixels in each image that are intersected by a vector projected from a point of origin for each image to at least one point in the depth map for each column as each of those vectors passes through the common viewing plane; and blend at least one identified pixel from each image with at least one identified pixel from at least one overlapping image for pixels at the same level within each column to create common composite pixels for each overlapping image. 17. The computer-implemented process of claim 16 wherein the depth map for each column is computed by using a plane sweep from a virtual origin aligned with each column. 18. The computer-implemented process of claim 16 wherein the depth map for each column is computed using actual pixel measurements. 19. The computer-implemented process of claim 16 wherein blending the pixels is achieved by a weighted averaging of the pixels that are blended. 20. The computer-implemented process of claim 16 further comprising warping each image back to its original viewing plane after pixel blending. 21. A computer-readable medium having computer executable instructions for automatically blending pixels to create common composite pixels in at least two overlapping images, said computer executable instructions comprising: input at least one pair of partially overlapping images; warp each pair of images into a common viewing plane; identify and align an overlapping region of the pair of images; divide the overlapping region into a set of columns of one pixel in width; compute a depth map for each column using a plane sweep in combination with a virtual viewing origin for mapping pixel depths throughout each column; identify pixels in each image pair that are intersected by a vector projected from a point of origin for each image to at least one point in the depth map for each column as each of those vectors passes through the common viewing plane; and blend at least one identified pixel from each image with at least one identified pixel from at least one overlapping image for pixels at the same level within each column by averaging the identified pixels to create at least one composite pixel. 22. The computer-readable medium of claim 21 wherein the averaging is a weighted averaging. 23. The computer-readable medium of claim 21 further comprising an inverse warping of the images following pixel blending to place each image back into an original viewing perspective. 24. The computer-readable medium of claim 21 wherein each composite pixel replaces each corresponding pixel in each corresponding column of the overlapping region. 25. The computer-readable medium of claim 24 wherein replacing each corresponding pixel in each corresponding column serves to create a set of composite columns that are common to each overlapping image. 26. The computer-readable medium of claim 23 wherein the inverse warped images are stored to a computer readable medium.