Electronic image-movement correcting device with a variable correction step feature

• US 5,825,415 A
• Filed: 08/01/1997
• Issued: 10/20/1998
• Est. Priority Date: 12/17/1993
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kaneda, Kitahiro, Inou, Kazuya
• Primary Examiner(s): GARBER, WENDY RAE
• Application Number:
  US08/904,455
• Time in Patent Office: 445 Days
• Field of Search: 348/208, 348/240, 348/207
• US Class Current: 348/208.6
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 23/6811 based on the image signal
• CPC Class Codes: H04N 23/683 performed by a processor, e.g. controlling the readout of an image memory

Abstract

An image-shake correcting device includes a motion-vector detecting circuit for detecting a motion vector relative to pictures, an electronic correcting circuit for electronically correcting an image shake on the basis of the motion vector detected by the motion-vector detecting circuit, an image enlarging circuit for performing enlargement processing on an image signal outputted from the electronic correcting circuit, and a control circuit for controlling a correction step of the electronic correcting circuit on the basis of an image enlargement ratio of the image enlarging circuit to set the correction step to an optimum state.

Claims

1. An image-movement correcting device comprising:

(a) motion-vector detecting means for detecting a motion vector relative to a plurality of pictures;

(b) electronic movement correcting means for electronically correcting an image movement on the basis of an output of said motion-vector detecting means;

(c) image enlarging means for performing enlargement processing on an image signal outputted from said electronic movement correcting means; and

(d) control means for controlling a unit amount of correction for a correction step of said electronic movement correcting means in accordance with an image enlargement ratio of said image enlarging means.

2. An image-movement correcting device according to claim 1, further comprising image pickup means for picking up an image signal, wherein said motion-vector detecting means detects a motion vector of an image from the picked-up image signal outputted from said image pickup means.

3. An image-movement correcting device according to claim 1, wherein said electronic movement correcting means has an image memory for storing an image and corrects the image movement by shifting an image reading position of said image memory in a direction of the motion vector outputted from said motion-vector detecting means.

4. An image-movement correcting device according to claim 3, wherein said electronic movement correcting means performs image-movement correction on each of luminance and chrominance signals.

5. An image-movement correcting device according to claim 2, wherein said motion-vector detecting means detects the motion vector on the basis of a two-level signal into which the picked-up image signal is converted by a band-pass filter, wherein the band-pass filter is arranged to convert the picked-up image signal into a two-level form.

6. An image-movement correcting device according to claim 3, wherein said electronic movement correcting means includes computing means for computing an absolute deviation from a reference position of the image on the basis of the motion vector detected by said motion-vector detecting means, and corrects the image movement by shifting the image reading position of said image memory on the basis of the absolute deviation.

7. An image-movement correcting device according to claim 1, wherein said control means makes the correction step of said electronic movement correcting means large if the image enlargement ratio of said image enlarging means is within a predetermined range, whereas if the image enlargement ratio of said image enlarging means is outside the predetermined range, said control means makes the correction step of said electronic movement correcting means small.

8. An image-movement correcting device comprising:

(a) a motion-vector detecting circuit that detects a motion vector relative to a plurality of pictures;

(b) an electronic movement correcting circuit that electronically corrects an image movement on the basis of an output of said motion-vector detecting circuit, said electronic movement correcting circuit having an image memory for storing an image and correcting the image movement by shifting an image reading position of said image memory in a direction of the motion vector outputted from said motion-vector detecting circuit;

(c) an image enlarging circuit that performs enlargement processing on an image signal outputted from said electronic movement correcting circuit; and

(d) a control circuit that controls a unit amount of shifting by said electronic movement correcting circuit in accordance with an image enlargement ratio of said image enlarging means.

9. An image-movement correcting device according to claim 8, further comprising an image pickup device, wherein said motion-vector detecting circuit detecting a motion vector of an image from a picked-up image signal outputted from said image pickup device.

10. An image-movement correcting device according to claim 8, wherein said electronic movement correcting circuit performs image-movement correction on each of luminance and chrominance signals.

11. An image-movement correcting device according to claim 9, wherein said motion-vector detecting circuit detects the motion vector on the basis of a two-level signal into which the picked-up image signal is converted by a band-pass filter, wherein the band-pass filter is arranged to convert the picked-up image signal into a two-level form.

12. An image-movement correcting device according to claim 8, wherein said electronic movement correcting circuit includes computing circuit for computing an absolute deviation from a reference position of the image on the basis of the motion vector detected by said motion-vector detecting circuit, and corrects the image movement by shifting the image reading position of said image memory on the basis of the absolute deviation.

13. An image-movement correcting device according to claim 8, wherein said control circuit makes the shifting step of said electronic movement correcting circuit large if the image enlargement ratio of said image enlarging circuit is within a predetermined range, whereas if the image enlargement ratio of said image enlarging circuit is outside the predetermined range, said control circuit makes the shifting step of said electronic movement correcting circuit small.

14. An image-movement correcting device according to claim 9, wherein said image pickup device includes a large-area image pickup element having an area larger than a normal image pickup area, and wherein said electronic movement correcting circuit corrects the image movement by shifting an image reading position of said large-area image pickup element in a direction of the motion vector outputted from said motion-vector detecting circuit.

15. An image-stabilizing device comprising:

(a) motion-vector detecting means for detecting a motion vector relative to a plurality of pictures;

(b) movement correcting means for correcting an image movement on the basis of an output of said motion-vector detecting means;

(c) image enlarging means for performing enlargement processing on an image signal outputted from said movement correcting means; and

(d) control means for controlling a unit amount of correction for a correction step of said movement correcting means in accordance with an image enlargement ratio of said image enlarging means.

16. An image-stabilizing device according to claim 15, further comprising image pickup means for picking up an image signal, wherein said motion-vector detecting means detects a motion vector of an image from the picked-up image signal outputted from said image pickup means.

17. An image-stabilizing device according to claim 15, wherein said movement correcting means has an image memory for storing an image and electronically corrects the image movement by shifting an image reading position of said image memory in a direction of the motion vector outputted from said motion-vector detecting means.

18. An image-stabilizing device according to claim 17, wherein said movement correcting means performs image-movement correction on each of luminance and chrominance signals.

19. An image-stabilizing device according to claim 16, wherein said motion-vector detecting means detects the motion vector on the basis of a two-level signal into which the picked-up image signal is converted by a band-pass filter, wherein the band-pass filter is arranged to convert the picked-up image signal into a two-level form.

20. An image-stabilizing device according to claim 17, wherein said movement correcting means includes computing means for computing an absolute deviation from a reference position of the image on the basis of the motion vector detected by said motion-vector detecting means, and corrects the image shake by shifting the image reading position of said image memory on the basis of the absolute deviation.

21. An image-stabilizing device according to claim 15, wherein said control means makes the correction step of said movement correcting means large if the image enlargement ratio of said image enlarging means is within a predetermined range, whereas if the image enlargement ratio of said image enlarging means is outside the predetermined range, said control means makes the correction step of said movement correcting means small.

22. An image movement correcting device comprising:

(a) motion-vector detecting means for detecting a motion vector;

(b) movement correcting means for correcting an image movement on the basis of an output of said motion-vector detecting means;

(c) image enlarging means for performing an enlargement operation on an image; and

(d) control means for controlling a unit amount of correcting by said movement correcting means in accordance with an image enlargement ratio of said image enlarging means.

23. An image-movement correcting device according to claim 22, further comprising an image pickup device, wherein said motion-vector detecting means detects a motion vector of an image from a picked-up image signal outputted from said image pickup device.

24. An image-movement correcting device according to claim 22, wherein said movement correcting means electronically performs image-movement correction on each of luminance and chrominance signals.

25. An image-movement correcting device according to claim 23, wherein said motion-vector detecting circuit detects the motion vector on the basis of a two-level signal into which the picked-up image signal is converted by a band-pass filter, wherein the band-pass filter is arranged to convert the picked-up image signal into a two-level form.

26. An image-movement correcting device according to claim 23, wherein said movement correcting means includes an image memory for storing the image signal and a computing circuit for computing an absolute deviation from a reference position of the image on the basis of the motion vector detected by said motion-vector detecting means, and corrects the image movement by shifting the image reading position of said image memory on the basis of the absolute deviation.

27. An image-movement correcting device according to claim 26, wherein said control means makes the shifting step of said movement correcting means large if the image enlargement ratio of said image enlarging means is within a predetermined range, whereas if the image enlargement ratio of said image enlarging means is outside the predetermined range, said control means makes the shifting step of said movement means correcting means small.

28. An image-movement correcting device according to claim 27, wherein said image pickup device includes a large-area image pickup element having an area larger than a normal image pickup area, and wherein said movement correcting means corrects the image movement by shifting an image reading position of said large-area image pickup element in a direction of the motion vector outputted from said motion-vector detecting means.