Zoom method of a digital camera based on extracted values

• US 7,742,085 B2
• Filed: 12/10/2003
• Issued: 06/22/2010
• Est. Priority Date: 12/12/2002
• Status: Expired due to Fees

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Shin, Jun Yong
• Primary Examiner(s): Chan; Jason
• Assistant Examiner(s): KHAN, USMAN A
• Application Number:
  US10/731,025
• Publication Number:
  US 20040119852A1
• Time in Patent Office: 2,386 Days
• Field of Search: 348/208.6, 348/211.9, 348/240.99, 348/240.1, 348/240.2, 348/240.3, 348/347, 348/222.1, 348/223.1
• US Class Current: 348/240.99
• CPC Class Codes: H04N 23/61 based on recognised objects
• CPC Class Codes: H04N 23/635 Region indicators; Field of view indicators
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming

Abstract

A zoom method of a small digital camera is provided that includes searching a center search line of a photographic screen according to a set photographic mode and searching upper and lower lines based on the center search line so as to extract a color average value and a deviation of a photographic object. A size of a photographic object may be calculated based on the average value and the deviation. A zoom ratio may be set according to a size of the photographic object. A portrait mode and a text mode may be implemented by software without influencing a size of a mobile communication terminal and so as to fast process the zoom function.

Claims

1. A zoom method comprising:

searching a center search line of a photographic screen, wherein the center search line comprises a horizontal axis at an approximate center of the photographic screen;

searching each of a plurality of upper search lines from the center search line;

searching each of a plurality of lower search lines from the center search line;

extracting a color average value and a deviation of a photographic object within the photographic screen for each of the plurality of upper search lines and the plurality of lower search lines;

determining a size of photographic object based on the extracted color average value and the extracted deviation for each of the plurality of upper search lines and the plurality of lower search lines, wherein determining the size of the photographic object includes determining a number of pixels that exist within a range of a certain deviation from an average value of a specific color and determining an area of the photographic object based on the determined number of pixels; and

setting a zoom ratio by comparing the determined size of the photographic object with a reference value or with a preset size.

2. The method of claim 1, wherein determining the size of the photographic object comprises:

analogizing a size of the photographic object by calculating the average value and the deviation; and

judging whether the photographic object is a normal region corresponding to a photographic mode.

3. The method of claim 2, further comprising converting a digital camera into a user hand mode so that a user can perform a direct zoom processing when the photographic object is not a normal region.

4. The method of claim 1, wherein searching the center search line comprises:

setting a photographic mode;

preprocessing the photographic screen; and

performing a line scanning at a region of the center search line.

5. The method of claim 4, wherein preprocessing the photographic screen comprises performing one of a smoothing method and a blurring method for minimizing error generation.

6. The method of claim 1, further comprising detecting the photographic object by the searching of the center search line.

7. The method of claim 1, wherein searching each of the plurality of upper search lines and each of the plurality of lower search lines comprises performing a line-scanning, and searching lines set with a predetermined gap up and down one line by one line.

8. The method of claim 1, wherein when the photographic object is not detected, the method further comprises:

resetting the center search line;

resetting upper search lines and lower search lines based on the reset center search line; and

searching each of the plurality of upper search lines and the plurality of lower search lines based on the reset search line.

9. The method of claim 1, wherein the reference value comprises one of a value manually preset by a user and a value preset based on a screen contrast.

10. A zoom method comprising:

searching a plurality of lines of a photographic screen by alternatively searching lines with a pre-determined gap up or down one line by one line;

for each of the plurality of lines, extracting a color average value and a deviation of a photographic object on the photographic screen;

determining a size of a photographic object based on the extracted color average value and the extracted deviation for each of the plurality of lines, wherein determining the size of the photographic object includes determining a number of pixels that exist within a range of a certain deviation from an average value of a particular color and determining an area of the photographic object based on the determined number of pixels;

determining a zoom ratio by comparing the determined size of the photographic object and a reference value; and

applying the determined zoom ratio to the photographic object.

11. The method of claim 10, further comprising:

setting a center search line of the photographic screen, and wherein the extracting includes performing a line scan of the center search line to extract the color average value and the deviation.

12. The method of claim 10, further comprising:

preprocessing the photographic screen according to a set photographic mode.

13. The method of claim 12, wherein the photographic mode comprises one of a portrait mode and a text mode.

14. The method of claim 12, wherein the preprocessing comprises one of a smoothing method and a blurring method for minimizing error generation.

15. The method of claim 11, wherein the center search line comprises a horizontal axis at an approximate center of the photographic screen for performing a line scan in order to detect the photographic object.

16. The method of claim 11, further comprising resetting the center search line when the photographic object is not detected along the center search line, and wherein the extracting includes performing a line scan based on the reset center search line.

17. The method of claim 10, further comprising converting into a user hand mode so that a user can perform a direct zoom processing when the photographic object is not a normal region.

18. The method of claim 10, wherein the reference value comprises one of a value preset manually by a user and a value preset based on a screen contrast.

19. A zoom method of a digital camera apparatus associated with a mobile communication terminal, the method comprising:

searching a center search line of a photographic screen to detect a photographic object, wherein the center search line is approximately at a center of the photographic screen;

searching a plurality of upper search lines of the center search line to extract an average value and a deviation of a skin color of the photographic object for each of the upper search lines;

searching a plurality of lower search lines of the center search line to extract an average value and a deviation of a skin color of the photographic object for each of the lower search lines;

determining a size of a face region based on the extracted average value and the extracted deviation of the skin color for each of the plurality of upper search lines and based on the extracted average value and the extracted deviation of the skin color for each of the plurality of lower search lines, wherein determining the size of the face region includes determining a number of pixels that exist within a range of a certain deviation from an average value of a skin color and determining an area of the face region based on the determined number of pixels;

comparing the determined size of the face region with a reference value;

calculating a zoom ratio based on the comparing; and

applying the calculated zoom ratio to the photographic screen.

20. The method of claim 19, further comprising resetting a search line and searching the reset search line.

21. The method of claim 19, wherein searching the plurality of upper search lines and searching the plurality of lower search lines comprises alternatively searching lines set with a predetermined gap up and down one line by one line.

22. The method of claim 19, wherein determining the size of the face region further comprises:

analogizing a length of a longest search line as a face width by obtaining a length variation through search lines having a smaller gap than the upper and lower search lines.

23. The method of claim 19, wherein determining the size of the face region further comprises judging whether a calculated face region is a normal photographic object.

24. The method of claim 23, further comprising converting the digital camera into a user hand mode so that a user can perform a direct zoom processing when the determined face region is not a normal photographic object.

25. The method of claim 19, wherein when a plurality of skin colors more than a certain length exist along the center search line and skin colors of a same pattern are detected at adjacent upper and lower search lines, the method further comprises:

determining that a plurality of photographic objects exist;

extracting an average value and a deviation of a skin color for each photographic object that is determined to be a face;

determining an area of a face region by obtaining a number of pixels that exist within a range of a certain deviation from an average value of each skin color; and

zooming a photographic screen with a preset zoom ratio based on the number of pixels and the determined area of the photographic objects.