Image sensing device that can correct colors corresponding to skin in a video signal

• US 6,072,526 A
• Filed: 07/03/1997
• Issued: 06/06/2000
• Est. Priority Date: 10/15/1990
• Status: Expired due to Fees

• Current Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Original Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Inventors: Sasaki, Gen, Mizumoto, Kenji, Hashimoto, Nobuo, Kubo, Hiroaki, Ochi, Keizou, Katoh, Takehiro, Ootsuka, Hiroshi, Azuma, Yoshihiko
• Primary Examiner(s): HO, TUAN V
• Application Number:
  US08/887,792
• Time in Patent Office: 1,069 Days
• Field of Search: 348/222, 348/223, 348/228, 348/229, 348/225, 348/226, 348/649, 348/650, 348/652, 348/653, 348/647, 348/719
• US Class Current: 348/223.1
• CPC Class Codes: H04N 9/643 Hue control means, e.g. flesh tone control

Abstract

An automatic exposure control apparatus comprises a skin color extracting circuit for extracting a skin-colored portion from an input video signal and a focus condition detecting circuit for detecting a focus condition of the skin-colored portion. Exposure is controlled based on outputs of the two circuits. That is, when a skin-colored portion is extracted and it is detected that the skin-colored portion is in an in-focus condition, exposure is controlled so as to be appropriate with respect to the skin-colored portion. A skin color correction unit can correct colors corresponding to the skin color from the video signal.

Claims

1. An image sensing device comprising:

an image sensing unit for sensing an image to generate a video signal;

a white balance correction unit for correcting the video signal according to a color temperature;

a selector unit for permitting a user to select one of a plurality of levels of color reproduction correction to be applied to the video signal corrected by the white balance correction unit;

a color reproduction correction unit for correcting colors which are reproduced based on said corrected video signal, including a lookup table which converts a part of the video signal into preset data stored therein, the color reproduction correction is performed by rewriting the lookup table in accordance with the level of color reproduction correction indicated by the selector unit; and

a controller for controlling said color reproduction correction unit to change contents of color reproduction correction performed by said color reproduction correction unit, wherein said controller changes the contents of the color reproduction correction by rewriting said lookup table.

2. An image sensing device as claimed in claim 1, further comprising:

a color separation unit for separating the video signal generated by said image sensing unit into three signals for red, green, and blue colors,

wherein said color reproduction correction unit adds together the signals for red, green, and blue colors to obtain a signal for white color and divides the signals for red and blue colors individually by the signal for white color to input resulting signals to said lookup table, and

wherein said lookup table converts the signals inputted thereto into preset data stored therein.

3. A method of correcting only colors corresponding to skin color among colors which are reproduced based on a video signal obtained by sensing an image, comprising the steps of:

(1) separating said video signal into three color signals for red, green, and blue colors;

(2) adding together the signals for red, green, and blue colors to obtain a signal for white color;

(3) dividing the signals for red and blue colors individually by the signal for white color;

(4) converting the signals resulting from the division in step (3) into preset data;

(5) multiplying signals resulting from the conversion in step (4) individually by the signal for white color;

(6) subtracting signals resulting from the multiplication in step (5) from the signal for white color; and

(7) outputting signals resulting from the conversion in step (4) and a signal resulting from the subtraction in step (6) as corrected R, G, and B signals.

4. A method of performing color correction on a sensed image, comprising the steps of:

generating a video signal;

correcting the video signal according to a color temperature;

selecting one of a plurality of types of color correction to be performed on the video signal corrected according to the color temperature;

performing color correction on said corrected video signal according to a lookup table having preset data stored herein; and

controlling said color correction by rewriting said lookup table, the color correction is performed by rewriting the preset data in the lookup table according to the selected type of color correction.

5. An image sensing device comprising:

an image sensing unit for sensing an image to generate a video signal;

a white balance correction unit for correcting the video signal according to a color temperature;

a selector unit for selecting a level of skin color correction, from a plurality of levels each representative of a different type of skin color, to be applied to the video signal corrected by the white balance correction unit;

a skin color correction unit for correcting colors corresponding to skin color among colors which are reproduced based on the video signal and rewriting preset data according to the level selected by the selector unit, said skin color correction unit generates a color signal corresponding to skin color from said corrected video signal, and converts the generated color signal into preset data stored therein; and

a controller for controlling said skin color correction unit to change contents of skin color correction performed by said skin color correction unit, said controller changes the contents of the skin color correction by rewriting said preset data.

6. An image sensing device comprising:

an image sensing unit for sensing an image to generate a video signal;

a color reproduction correction unit for correcting colors which are reproduced based on the video signal including a lookup table;

a controller for controlling said color reproduction correction unit to change contents of color reproduction correction performed by said color reproduction correction unit; and

a color separation unit for separating the video signal generated by said image sensing unit into three signals for red, green, and blue colors,

wherein said color reproduction correction unit adds together the signals for red, green, and blue colors to obtain a signal for white color and divides the signals for red and blue colors individually by the signal for white color to input resulting signals to said lookup table, and wherein said lookup table converts the signals inputted thereto into preset data stored therein.