Apparatus and method for providing panoramic images

• US 6,798,923 B1
• Filed: 02/04/2000
• Issued: 09/28/2004
• Est. Priority Date: 02/04/2000
• Status: Expired

• Current Assignee: Transpacific IP Group Limited
• Original Assignee: Industrial Technology Research Institute
• Inventors: Hsieh, Jun-Wei, Way, Der-Lor, Chiang, Cheng-Chin
• Primary Examiner(s): PATEL, KANJIBHAI B
• Application Number:
  US09/498,291
• Time in Patent Office: 1,698 Days
• Field of Search: 382/151, 382/162, 382/154, 382/169, 382/190, 382/195, 382/199, 382/201, 382/203, 382/216, 382/219, 382/254, 382/266, 382/268, 382/240, 382/278, 382/284, 382/289, 382/294, 382/295, 382/296, 345/629, 345/683, 345/630, 345/648, 348/222, 348/36, 348/218
• US Class Current: 382/284
• CPC Class Codes: G06T 3/403 Edge-driven scaling; Edge-based scaling
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 5/2624 for obtaining an image which is composed of whole input images, e.g. splitscreen

Abstract

A method and system of merging a pair of images to form a seamless panoramic image including the following steps. A set of feature points are extracted along the edges of the images, each feature point defining an edge orientation. A set of registration parameters is obtained by determining an initial set of feature points from a first one of the images which matches a set of feature points of a second one of the images. A seamless panoramic image is rendered using the first and second images with the set of registration parameters.

Claims

1. A method of merging a different pair of images to form a seamless panoramic image comprising:

extracting a set of feature points along the edges of the images, each feature point defining an edge orientations, wherein

extracting the set of feature points along the edges of the images includes applying wavelet transforms to the images;

obtaining a set of registration parameters by determining an initial set of feature points from a first one of the images which matches a set of feature points of a second one of the images; and

rendering a seamless panoramic image using the first and second images with the set of registration parameters.

2. The method of claim 1, wherein determining the initial set of matching pairs includes a relaxation technique, including the steps of:

calculating the edge orientation of each feature point;

comparing the orientation difference between the matching pair;

calculating the value of correlation of the matching pair; and

comparing the value of correlation with a predefined threshold.

3. The method of claim 1, wherein extracting the set of feature points, includes:

calculating an edge correlation for each image;

locating the feature point whose edge response is the maxima within a window;

comparing the maxima with a predefined threshold.

4. The method of claim 1, wherein obtaining the set of reliable registration parameters, comprises:

determining an initial set of matching pairs for registration;

calculating a quality value for the initial set of matching pairs;

updating the matching result according to the quality value of the match;

imposing an angle consistency constraint to filter out impossible matches; and

using a voting technique to obtain the registration parameters.

5. The method of claims 1, wherein rendering the seamless panoramic image comprises:

dynamically adjusting the intensity differences between adjacent images; and

properly blending the intensity difference between consecutive images.

6. A system for merging a pair of images to form a panoramic image comprising:

an image device which, in operation, acquires a series of images;

a storage for storing the series of images;

a memory which stores computer code; and

at least one processor which executes the computer code to;

extract different sets of feature points along the edges of each input image, each feature point defining an edge orientation;

extract a set of feature points along the edges of the images by applying wavelet formations to the images, each feature point defining an edge of orientation;

obtain a set of registration parameters by determining an initial set of feature points from a first one of the images which matches a set of feature points of a second one of the images; and

render a seamless panoramic image using the first and second images with the set of registration parameters.

7. The system of claim 6, wherein the processor extracts the set of feature points, including:

calculating an edge correlation for each image;

locating the feature point whose edge response is the maxima within a window;

comparing the maxima with a predefined threshold.