Object detection and rendering for wide field of view (WFOV) image acquisition systems
View Patent ↗An image acquisition device having a wide field of view includes a lens and image sensor configured to capture an original wide field of view (WFoV) image with a field of view of more than 90°. The device has an object detection engine that includes one or more cascades of object classifiers, e.g., face classifiers. A WFoV correction engine may apply rectilinear and/or cylindrical projections to pixels of the WFoV image, and/or non-linear, rectilinear and/or cylindrical lens elements or lens portions serve to prevent and/or correct distortion within the original WFoV image. One or more objects located within the original and/or distortion-corrected WFoV image is/are detectable by the object detection engine upon application of the one or more cascades of object classifiers.
1. An image acquisition device having a wide field of view, comprising:
a lens assembly and image sensor configured to capture an original wide field of view (WFoV) image with a field of view of more than 90°, wherein the lens assembly comprises a compressed rectilinear lens to capture a center region of a scene onto a middle portion of the image sensor such as to directly provide a rectilinear mapping of the center region and a cylindrical lens on one or both sides of the compressed rectilinear lens to capture outer regions of the scene onto outer portions of the image sensor such as to directly provide a cylindrical mapping of the outer regions;
a control module;
an object detection engine comprising one or more cascades of regular object classifiers;
wherein one or more objects located within the center or outer pixels, or both, of the original WFoV image are detectable by the object detection engine upon application of the one or more cascades of regular object classifiers.
2. The device of claim 1 , further comprising:
a full frame buffer coupled with the image sensor for acquiring raw image data;
a mixer; and
a zoom and pan engine.
3. The device of claim 1 , further comprising an object tracking engine.
4. The device of claim 1 , wherein the object classifiers comprise face classifiers.
5. The device of claim 1 , wherein the regular object classifiers comprise rectangular object classifiers.
6. An image acquisition device having a wide field of view, comprising:
a lens assembly and image sensor configured to capture an original wide field of view (WFoV) image with a field of view of more than 90°, wherein the lens assembly comprises a lens having a compressed rectilinear center portion to capture a center region of a scene onto a middle portion of the image sensor such as to directly provide a rectilinear mapping of the center region, and the lens also comprises cylindrical outer portions on either side of the compressed rectilinear portion to capture outer regions of the scene onto outer portions of the image sensor such as to directly provide a cylindrical mapping of the outer regions;
a control module;
a object detection engine comprising one or more cascades of regular object classifiers;
wherein one or more objects located within the center or outer pixels, or both, of the original WFoV image are detectable by the object detection engine upon application of the one or more cascades of regular object classifiers.
7. The device of claim 6 , further comprising:
a full frame buffer coupled with the image sensor for acquiring raw image data;
a mixer; and
a zoom and pan engine.
8. The device of claim 6 , further comprising an object tracking engine.
9. The device of claim 6 , wherein the object classifiers comprise face classifiers.
10. The device of claim 6 , wherein the regular object classifiers comprise rectangular object classifiers.