High-resolution video conferencing system

• US 5,757,424 A
• Filed: 12/19/1995
• Issued: 05/26/1998
• Est. Priority Date: 12/19/1995
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Frederick, Ronald A.
• Primary Examiner(s): Faile, Andrew
• Assistant Examiner(s): MOE, AUNG SOE
• Application Number:
  US08/574,706
• Time in Patent Office: 889 Days
• Field of Search: 348/218, 348/15, 348/214, 348/19, 348/159, 348/143, 348/17, 348/584, 348/586, 348/154, 348/588, 386/46, 386/117, 386/38
• US Class Current: 348/218.1
• CPC Class Codes: H04N 7/147 Communication arrangements, e.g. identifying the communication as a video-communication, intermediate storage of the signals selecting H04Q
• CPC Class Codes: H04N 7/15 Conference systems

Abstract

A system enables high-resolution videoconferencing images to be transmitted, without extreme demands on bandwidth. A mosaicing camera sequentially samples a series of small portions of a general scene, and a composite image of the entire general scene is transmitted. Simultaneously, an individual small area of the general scene where high time resolution is desirable is sampled at a high time resolution by a dedicated camera. The high-time-resolution images are then patched into the composite image.

Claims

1. A method of transmitting an image representing a scene in real time, comprising the steps of:

a mosaicing camera sampling at least a first portion and a second portion of the scene, outputting a first mosaic image and a second mosaic image, each of the first mosaic image and the second mosaic image comprising a set of pixels forming a coherent image;

combining the first mosaic image and the second mosaic image whereby pixels from the first mosaic image abut pixels from the second mosaic image, yielding a coherent composite image;

a first specific camera sampling a first specific portion of the scene, outputting a first specific image, the first specific image including at least a portion of the scene sampled in the first mosaic image or the second mosaic image; and

substituting pixels from the first specific image into the composite image, yielding a coherent final image.

2. The method of claim 1, further comprising the steps of

the mosaicing camera sampling each of the first portion and a second portion of the scene at a first frame rate;

and

the first specific camera sampling the first specific portion of the scene at a second frame rate different from the first frame rate.

3. The method of claim 1, further comprising the step of deriving a patch algorithm for the first specific camera, the patch algorithm including information relating to a position of the first specific camera relative to the composite image.

4. The method of claim 3, further comprising the step of selecting pixels in the composite image to be substituted with pixels from the first specific image, based on the patch algorithm.

5. The method of claim 1, further comprising the step of positioning the mosaicing camera in a periodic sequence of predetermined positions relative to the scene.

6. The method of claim 5, further comprising the step of deriving a patch algorithm for the mosaicing camera, the patch algorithm including information relating to a position of the mosaicing camera relative to the scene.

7. The method of claim 1, further comprising the steps of

transmitting pixel signals relating to the composite image;

and

transmitting pixel signals relating to the first specific camera;

and wherein the the substituting step includes the step of substituting pixels from the first specific image into the composite image at a receiving station.

8. The method of claim 1, further comprising the steps of

a second specific camera sampling a second specific portion of the scene, outputting a second specific image, the second specific image including a least a portion of the scene sampled in the first mosaic image or the second mosaic image;

and

substituting pixels from the second specific image into the composite image, yielding a coherent final image.

9. The method of claim 8, further comprising the step of selecting the first specific image or the second specific image for substitution into the composite image.

10. The method of claim 9, further comprising the steps of

detecting image motion in either the first specific portion of the scene or the second specific portion of the scene;

and

selecting the first specific image or the second specific image for substitution into the composite image depending on whether image motion is detected in either the first specific portion of the scene or the second specific portion of the scene.

11. The method of claim 9, further comprising the steps of

associating a microphone with each of the first specific portion of the scene or and second specific portion of the scene;

and

selecting the first specific image or the second specific image for substitution into the composite image depending on whether sound is detected by a microphone in either the first specific portion of the scene or the second specific portion of the scene.

12. An apparatus for transmitting an image representing a scene in real time, comprising:

a mosaicing camera adapted to sample at least a first portion and a second portion of the scene, outputting a first mosaic image and a second mosaic image, each of the first mosaic image and the second mosaic image comprising a set of pixels forming a coherent image;

means for combining the first mosaic image and the second mosaic image whereby pixels from the first mosaic image abut pixels from the second mosaic image, yielding a coherent composite image;

a first specific camera adapted to sample a first specific portion of the scene, outputting a first specific image, the first specific image including at least a portion of the scene sampled in the first mosaic image or the second mosaic image; and

means for substituting pixels from the first specific image into the composite image, yielding a coherent final image.

13. The apparatus of claim 12, wherein the mosaicing camera is adapted to sample each of the first portion and a second portion of the scene at a first frame rate;

and

wherein the first specific camera is adapted to sample the first specific portion of the scene at a second frame rate different from the first frame rate.

14. The apparatus of claim 12, further comprising means for deriving a patch algorithm for the first specific camera, the patch algorithm including information relating to a position of the first specific camera relative to the composite image.

15. The apparatus of claim 14, further comprising means for selecting pixels in the composite image to be substituted with pixels from the first specific image, based on the patch algorithm.

16. The apparatus of claim 12, further comprising means for positioning the mosaicing camera in a periodic sequence of predetermined positions relative to the scene.

17. The apparatus of claim 16, further comprising means for deriving a patch algorithm for the mosaicing camera, the patch algorithm including information relating to a position of the mosaicing camera relative to the scene.

18. The apparatus of claim 12, further comprising

a second specific camera adapted to sample a second specific portion of the scene, outputting a second specific image, the second specific image including a least a portion of the scene sampled in the first mosaic image or the second mosaic image;

means for substituting pixels from the second specific image into the composite image, yielding a coherent final image;

means for detecting image motion in either the first specific portion of the scene or the second specific portion of the scene; and

means for selecting the first specific image or the second specific image for substitution into the composite image depending on whether image motion is detected in either the first specific portion of the scene or the second specific portion of the scene.

19. The apparatus of claim 12, further comprising

a second specific camera adapted to sample a second specific portion of the scene, outputting a second specific image, the second specific image including a least a portion of the scene sampled in the first mosaic image or the second mosaic image;

means for substituting pixels from the second specific image into the composite image, yielding a coherent final image;

a microphone associated with each of the first specific portion of the scene or and second specific portion of the scene; and

means for selecting the first specific image or the second specific image for substitution into the composite image depending on whether sound is detected by a microphone in either the first specific portion of the scene or the second specific portion of the scene.