Equatorial Stitching Of Hemispherical Images In A Spherical Image Capture System
AssigneeGoPro, Inc.
InventorsJoseph Steel, Timothy Macmillan
Life of this patent
Estimating the term…
Abstract
Hyper-hemispherical images may be combined to generate a rectangular projection of a spherical image having an equatorial stitch line along of a line of lowest distortion in the two images. First and second circular images are received representing respective hyper-hemispherical fields of view. A video processing device may project each circular image to a respective rectangular image by mapping an outer edge of the circular image to a first edge of the rectangular image and mapping a center point of the circular image to a second edge of the first rectangular image. The rectangular images may be stitched together along the edges corresponding to the outer edge of the original circular image.
Claims20
A method of performing equatorial stitching, comprising:
- capturing a first image and a second image;
- mapping first pixels of the first image to a first f-theta projection based on a calibration;
- mapping second pixels of the second image to a second f-theta projection based on the calibration;
- offsetting a first center and a first orientation of the first f-theta projection based on the calibration;
- offsetting a second center and a second orientation of the second f-theta projection based on the calibration;
- back-projecting the first pixels of the first image and the second pixels of the second image to a sphere centered on a midpoint of the first f-theta projection and the second f-theta projection;
- mapping the sphere to an equirectangular projection comprising an equator;
- and
- stitching the equirectangular projection at the equator to create a stitched polar view image.
An imaging apparatus configured to equatorial stitching, the imaging apparatus comprising:
- a processor;
- a first camera facing a first direction;
- a second camera facing a second direction different from the first direction;
- and
- a non-transitory computer-readable apparatus comprising computer instructions, the computer instructions configured to, when executed by the processor, cause the imaging apparatus to:
- capture a first image via the first camera and a second image via the second camera;
- map the first image to a first f-theta projection and the second image to a second f-theta projection;
- offset a first center and a first orientation of the first f-theta projection and a second center and a second orientation of the second f-theta projection;
- back-project the first image and the second image to a sphere centered on a midpoint of the first f-theta projection and the second f-theta projection;
- map the sphere to an equirectangular projection comprising an equator;
- and
- stitch the equirectangular projection at the equator to create a stitched polar view image.
A non-transitory computer-readable medium comprising one or more instructions which, when executed by a processor, causes the processor to:
- map a first image to a first f-theta projection and a second image to a second f-theta projection;
- offset a first center and a first orientation of the first f-theta projection and a second center and a second orientation of the second f-theta projection;
- back-project the first image and the second image to a sphere centered on a midpoint of the first f-theta projection and the second f-theta projection;
- map the sphere to an equirectangular projection comprising an equator;
- and
- stitch the equirectangular projection at the equator to create a stitched polar view image.
Dependencies are inferred from the claim text.