Method, apparatus and system for processing a display from a surround view camera solution

• US 9,533,618 B2
• Filed: 03/09/2015
• Issued: 01/03/2017
• Est. Priority Date: 03/07/2014
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Zhang, Buyue, Pekkucuksen, Ibrahim, Appia, Vikram, Batur, Aziz Umit
• Primary Examiner(s): Wu, Jingge
• Application Number:
  US14/642,510
• Publication Number:
  US 20150254825A1
• Time in Patent Office: 666 Days
• US Class Current: 1/1
• CPC Class Codes: B60R 1/00 Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
• CPC Class Codes: B60R 1/27 providing all-round vision, e.g. using omnidirectional cameras
• CPC Class Codes: B60R 2300/303 using joined images, e.g. multiple camera images
• CPC Class Codes: B60R 2300/607 from a bird's eye viewpoint
• CPC Class Codes: G06T 3/4038 Image mosaicing, e.g. composing plane images from plane sub-images

Abstract

A method, apparatus and a system multi-camera image processing method. The method includes performing geometric alignment to produce a geometric output, performing photometric alignment to produce a photometric output and blending output, using data from the geometric alignment and the photometric alignment for performing synthesis function for at least one of blending and stitching images from the multi-cameras, and displaying an image from the synthesis function.

Claims

1. A multi-camera image processing method, comprising:

performing geometric alignment to produce a geometric output, wherein performing the geometric alignment includes;

performing perspective correction on each of a plurality of frames;

performing corner detection in overlapping areas to find regions of interest;

filtering corner data to locate corners;

calculating a descriptor for each of the corners;

matching corners from two cameras using scores;

finding perspective matrices for each of the frames for minimizing distances between matched features; and

creating a geometric lookup table that encodes fisheye lens distortion correction and perspective transformation information, the method further comprising;

performing photometric alignment to produce a photometric output and a blending output;

using the geometric output and the photometric output for performing a synthesis function for at least one of blending and stitching images obtained from the two cameras; and

displaying an image obtained from the synthesis function.

2. The multi-camera image processing method of claim 1, wherein the two cameras are two adjacent cameras, and wherein the synthesis function comprises using an alpha blend to blend images from the two adjacent cameras at a seam boundary to eliminate irregularities at the seam boundary caused by image data from the two adjacent cameras.

3. The multi-camera image processing method of claim 1, wherein the geometric function comprises a camera calibration.

4. The multi-camera image processing method of claim 3, wherein the camera calibration is at least one of a dynamic calibration and a one-time calibration.

5. The multi-camera image processing method of claim 1, wherein the input to the synthesis function includes fisheye frames from the two cameras, the geometric output, the photometric output.

6. The multi-camera image processing method of claim 1, wherein the geometric output, the photometric output and blending output are saved in a lookup table in a memory, a geometric lookup table and a photometric lookup table, respectively.

7. The multi-camera image processing method of claim 6, wherein an output of the photometric lookup table has 255 entries for 8-bit data input.

8. The multi-camera image processing method of claim 1, wherein the geometric alignment comprises camera calibration using calibration charts independent of any camera parameters.

9. An image processing system, comprising:

a memory; and

a processor coupled to the memory, the processor configured to;

perform geometric alignment to produce a geometric output;

perform perspective correction on each of a plurality of frames;

perform corner detection in overlapping areas to find regions of interest;

filter corner data to locate corners;

calculate a descriptor for each of the corners;

match the corners from two cameras using scores;

find perspective matrices for each of the frames for minimizing distances between matched features;

create a geometric lookup table that encodes fisheye lens distortion correction and perspective transformation information;

perform photometric alignment to produce a photometric output and blending output;

use the geometric output and the photometric output for performing a synthesis function for at least one of blending and stitching images obtained from the two cameras; and

display an image obtained from the synthesis function.

10. The image processing system of claim 9, wherein the two cameras are two adjacent cameras, and wherein the synthesis function comprises using an alpha blend to blend images from the two adjacent cameras at a seam boundary to eliminate irregularities at the seam boundary caused by image data from the two adjacent cameras.

11. The image processing system of claim 9, wherein the geometric function comprises a camera calibration.

12. The image processing system of claim 11, wherein the camera calibration is at least one of a dynamic calibration and a one-time calibration.

13. The image processing system of claim 9, wherein the input to the synthesis function includes fisheye frames from the multi-cameras, the geometric output, the photometric output.

14. The image processing system of claim 9, wherein the geometric output, the photometric output and blending output are saved in a lookup table in the memory, a geometric lookup table and a photometric lookup table, respectively.

16. The image processing system of claim 9, wherein the geometric alignment comprises camera calibration using calibration charts independent of any camera parameters.

15. The image processing system of claim, wherein an output of the photometric lookup table has 255 entries for 8-bit data input.