Image-processing devices, methods, and programs, and electronic cameras and the like comprising same

An image-processing device, comprising:

• an image-input unit configured to receive an input image;
• a fluctuation-extraction unit coupled to the image-input unit and configured to extract a local-fluctuation component from the input image and to generate a local-fluctuation image containing the local-fluctuation component;
• a modulation-signal-generation unit coupled to the image-input unit and the fluctuation-extraction unit, and configured to generate a modulation signal for modulating the input image to the local-fluctuation image;
• a level-compression unit coupled to the modulation-signal-generation unit and configured to level-compress the modulation signal;
• and
• a gradation-correction unit coupled to the level-compression unit and configured to modulate the input image with the level-compressed modulation signal, thereby producing a gradation-corrected image, wherein the gradation-correction unit further comprises an adjustment-input unit configured to accept, from a user, adjustment of a weighted ratio Ws for a shadow area and a weighted ratio Wh for a highlight area of the image;
• and an effect-adjustment unit configured to generate an output image by performing a weighted addition of the gradation-corrected image and the input image with the weighted ratio Wh in an area in which the modulation signal is no greater than a predetermined threshold value, and by performing a weighted addition of the gradation-corrected image and the input image with the weighted ratio Ws in an area in which the modulation signal has a threshold value exceeding the predetermined threshold value.

An image-processing device, comprising:

• an image-input unit configured to receive an input image;
• a fluctuation-extraction unit coupled to the image-input unit and configured to extract a local-fluctuation component from the input image and to generate a local-fluctuation image containing the local-fluctuation component;
• a modulation-signal-generation unit coupled to the image-input unit and the fluctuation-extraction unit, and configured to generate a modulation signal for modulating the input image to the local-fluctuation image;
• a level-compression unit coupled to the modulation-signal-generation unit and configured to level-compress the modulation signal;
• and
• a gradation-correction unit coupled to the level-compression unit and configured to modulate the input image with the level-compressed modulation signal, thereby producing a gradation-corrected image, wherein the modulation-signal-generation unit further comprises a range-adjustment unit configured to adjust a signal range of the local-fluctuation image to a predetermined range;
• and a signal-calculation unit configured to calculate a modulation signal for modulating the input image to the range-adjusted local-fluctuation image.

An image-processing method, comprising:

• extracting a local-fluctuation component from an input image to generate a local-fluctuation image containing the local-fluctuation component;
• generating a modulation signal and using the modulation signal for modulating the input image to the local-fluctuation image;
• compressing a level of the modulation signal;
• and
• a gradation-correction step comprising modulating the input image with the level-compressed modulation signal to produce a gradation-corrected image,
• wherein the input image is a color image comprising a plurality of components,
• the gradation-correction step producing the gradation-corrected image further comprises performing a weighted addition of a multiplied image and an offset-corrected image,
• the multiplied image is obtained by multiplying the level-compressed modulation signal and the plurality of components, and
• the offset-corrected signal is obtained by offset-correcting the plurality of components of the input image to align the input image in signal level with the multiplied image.

An image-processing method, comprising:

• extracting a local-fluctuation component from an input image to generate a local-fluctuation image containing the local-fluctuation component;
• generating a modulation signal and using the modulation signal for modulating the input image to the local-fluctuation image;
• compressing a level of the modulation signal;
• and
• a gradation-correction step comprising modulating the input image with the level-compressed modulation signal to produce a gradation-corrected image;
• accepting, from a user, an adjustment of a weighted ratio Ws for a shadow area and a weighted ratio Wh for a highlight area;
• and performing a weighted addition of the gradation-corrected image and the input image with the weighted ratio Wh in an area in which the modulation signal is no greater than a predetermined threshold value and performing a weighted addition of the gradation-corrected image and the input image with the weighted ratio Ws in an area in which the modulation signal has a threshold value exceeding the predetermined threshold value, to generate an output image.

An image-processing method, comprising:

• extracting a local-fluctuation component from an input image to generate a local-fluctuation image containing the local-fluctuation component;
• generating a modulation signal and using the modulation signal for modulating the input image to the local-fluctuation image;
• compressing a level of the modulation signal;
• and
• a gradation-correction step comprising modulating the input image with the level-compressed modulation signal to produce a gradation-corrected image;
• wherein the step of generating a modulation signal further comprises adjusting a signal range of the local-fluctuation image to a predetermined range, and calculating a modulation signal for modulating input image to the range-adjusted local-fluctuation image.